2004-05-13 Patrik Torstensson
[mono.git] / mono / mini / mini-x86.c
1 /*
2  * mini-x86.c: x86 backend for the Mono code generator
3  *
4  * Authors:
5  *   Paolo Molaro (lupus@ximian.com)
6  *   Dietmar Maurer (dietmar@ximian.com)
7  *   Patrik Torstensson
8  *
9  * (C) 2003 Ximian, Inc.
10  */
11 #include "mini.h"
12 #include <string.h>
13 #include <math.h>
14
15 #include <mono/metadata/appdomain.h>
16 #include <mono/metadata/debug-helpers.h>
17 #include <mono/metadata/profiler-private.h>
18 #include <mono/utils/mono-math.h>
19
20 #include "trace.h"
21 #include "mini-x86.h"
22 #include "inssel.h"
23 #include "cpu-pentium.h"
24
25 static gint lmf_tls_offset = -1;
26
27 #ifdef PLATFORM_WIN32
28 /* Under windows, the default pinvoke calling convention is stdcall */
29 #define CALLCONV_IS_STDCALL(call_conv) (((call_conv) == MONO_CALL_STDCALL) || ((call_conv) == MONO_CALL_DEFAULT))
30 #else
31 #define CALLCONV_IS_STDCALL(call_conv) ((call_conv) == MONO_CALL_STDCALL)
32 #endif
33
34 #define SIGNAL_STACK_SIZE (64 * 1024)
35
36 static gpointer mono_arch_get_lmf_addr (void);
37
38 const char*
39 mono_arch_regname (int reg) {
40         switch (reg) {
41         case X86_EAX: return "%eax";
42         case X86_EBX: return "%ebx";
43         case X86_ECX: return "%ecx";
44         case X86_EDX: return "%edx";
45         case X86_ESP: return "%esp";    case X86_EBP: return "%ebp";
46         case X86_EDI: return "%edi";
47         case X86_ESI: return "%esi";
48         }
49         return "unknown";
50 }
51
52 /*
53  * mono_arch_get_argument_info:
54  * @csig:  a method signature
55  * @param_count: the number of parameters to consider
56  * @arg_info: an array to store the result infos
57  *
58  * Gathers information on parameters such as size, alignment and
59  * padding. arg_info should be large enought to hold param_count + 1 entries. 
60  *
61  * Returns the size of the activation frame.
62  */
63 int
64 mono_arch_get_argument_info (MonoMethodSignature *csig, int param_count, MonoJitArgumentInfo *arg_info)
65 {
66         int k, frame_size = 0;
67         int size, align, pad;
68         int offset = 8;
69
70         if (MONO_TYPE_ISSTRUCT (csig->ret)) { 
71                 frame_size += sizeof (gpointer);
72                 offset += 4;
73         }
74
75         arg_info [0].offset = offset;
76
77         if (csig->hasthis) {
78                 frame_size += sizeof (gpointer);
79                 offset += 4;
80         }
81
82         arg_info [0].size = frame_size;
83
84         for (k = 0; k < param_count; k++) {
85                 
86                 if (csig->pinvoke)
87                         size = mono_type_native_stack_size (csig->params [k], &align);
88                 else
89                         size = mono_type_stack_size (csig->params [k], &align);
90
91                 /* ignore alignment for now */
92                 align = 1;
93
94                 frame_size += pad = (align - (frame_size & (align - 1))) & (align - 1); 
95                 arg_info [k].pad = pad;
96                 frame_size += size;
97                 arg_info [k + 1].pad = 0;
98                 arg_info [k + 1].size = size;
99                 offset += pad;
100                 arg_info [k + 1].offset = offset;
101                 offset += size;
102         }
103
104         align = MONO_ARCH_FRAME_ALIGNMENT;
105         frame_size += pad = (align - (frame_size & (align - 1))) & (align - 1);
106         arg_info [k].pad = pad;
107
108         return frame_size;
109 }
110
111 static const guchar cpuid_impl [] = {
112         0x55,                           /* push   %ebp */
113         0x89, 0xe5,                     /* mov    %esp,%ebp */
114         0x53,                           /* push   %ebx */
115         0x8b, 0x45, 0x08,               /* mov    0x8(%ebp),%eax */
116         0x0f, 0xa2,                     /* cpuid   */
117         0x50,                           /* push   %eax */
118         0x8b, 0x45, 0x10,               /* mov    0x10(%ebp),%eax */
119         0x89, 0x18,                     /* mov    %ebx,(%eax) */
120         0x8b, 0x45, 0x14,               /* mov    0x14(%ebp),%eax */
121         0x89, 0x08,                     /* mov    %ecx,(%eax) */
122         0x8b, 0x45, 0x18,               /* mov    0x18(%ebp),%eax */
123         0x89, 0x10,                     /* mov    %edx,(%eax) */
124         0x58,                           /* pop    %eax */
125         0x8b, 0x55, 0x0c,               /* mov    0xc(%ebp),%edx */
126         0x89, 0x02,                     /* mov    %eax,(%edx) */
127         0x5b,                           /* pop    %ebx */
128         0xc9,                           /* leave   */
129         0xc3,                           /* ret     */
130 };
131
132 typedef void (*CpuidFunc) (int id, int* p_eax, int* p_ebx, int* p_ecx, int* p_edx);
133
134 static int 
135 cpuid (int id, int* p_eax, int* p_ebx, int* p_ecx, int* p_edx)
136 {
137         int have_cpuid = 0;
138         __asm__  __volatile__ (
139                 "pushfl\n"
140                 "popl %%eax\n"
141                 "movl %%eax, %%edx\n"
142                 "xorl $0x200000, %%eax\n"
143                 "pushl %%eax\n"
144                 "popfl\n"
145                 "pushfl\n"
146                 "popl %%eax\n"
147                 "xorl %%edx, %%eax\n"
148                 "andl $0x200000, %%eax\n"
149                 "movl %%eax, %0"
150                 : "=r" (have_cpuid)
151                 :
152                 : "%eax", "%edx"
153         );
154
155         if (have_cpuid) {
156                 CpuidFunc func = (CpuidFunc)cpuid_impl;
157                 func (id, p_eax, p_ebx, p_ecx, p_edx);
158                 /*
159                  * We use this approach because of issues with gcc and pic code, see:
160                  * http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7329
161                 __asm__ __volatile__ ("cpuid"
162                         : "=a" (*p_eax), "=b" (*p_ebx), "=c" (*p_ecx), "=d" (*p_edx)
163                         : "a" (id));
164                 */
165                 return 1;
166         }
167         return 0;
168 }
169
170 /*
171  * Initialize the cpu to execute managed code.
172  */
173 void
174 mono_arch_cpu_init (void)
175 {
176         guint16 fpcw;
177
178         /* spec compliance requires running with double precision */
179         __asm__  __volatile__ ("fnstcw %0\n": "=m" (fpcw));
180         fpcw &= ~X86_FPCW_PRECC_MASK;
181         fpcw |= X86_FPCW_PREC_DOUBLE;
182         __asm__  __volatile__ ("fldcw %0\n": : "m" (fpcw));
183         __asm__  __volatile__ ("fnstcw %0\n": "=m" (fpcw));
184
185 }
186
187 /*
188  * This function returns the optimizations supported on this cpu.
189  */
190 guint32
191 mono_arch_cpu_optimizazions (guint32 *exclude_mask)
192 {
193         int eax, ebx, ecx, edx;
194         guint32 opts = 0;
195         
196         *exclude_mask = 0;
197         /* Feature Flags function, flags returned in EDX. */
198         if (cpuid (1, &eax, &ebx, &ecx, &edx)) {
199                 if (edx & (1 << 15)) {
200                         opts |= MONO_OPT_CMOV;
201                         if (edx & 1)
202                                 opts |= MONO_OPT_FCMOV;
203                         else
204                                 *exclude_mask |= MONO_OPT_FCMOV;
205                 } else
206                         *exclude_mask |= MONO_OPT_CMOV;
207         }
208         return opts;
209 }
210
211 static gboolean
212 is_regsize_var (MonoType *t) {
213         if (t->byref)
214                 return TRUE;
215         switch (t->type) {
216         case MONO_TYPE_I4:
217         case MONO_TYPE_U4:
218         case MONO_TYPE_I:
219         case MONO_TYPE_U:
220         case MONO_TYPE_PTR:
221                 return TRUE;
222         case MONO_TYPE_OBJECT:
223         case MONO_TYPE_STRING:
224         case MONO_TYPE_CLASS:
225         case MONO_TYPE_SZARRAY:
226         case MONO_TYPE_ARRAY:
227                 return TRUE;
228         case MONO_TYPE_VALUETYPE:
229                 if (t->data.klass->enumtype)
230                         return is_regsize_var (t->data.klass->enum_basetype);
231                 return FALSE;
232         }
233         return FALSE;
234 }
235
236 GList *
237 mono_arch_get_allocatable_int_vars (MonoCompile *cfg)
238 {
239         GList *vars = NULL;
240         int i;
241
242         for (i = 0; i < cfg->num_varinfo; i++) {
243                 MonoInst *ins = cfg->varinfo [i];
244                 MonoMethodVar *vmv = MONO_VARINFO (cfg, i);
245
246                 /* unused vars */
247                 if (vmv->range.first_use.abs_pos >= vmv->range.last_use.abs_pos)
248                         continue;
249
250                 if ((ins->flags & (MONO_INST_IS_DEAD|MONO_INST_VOLATILE|MONO_INST_INDIRECT)) || 
251                     (ins->opcode != OP_LOCAL && ins->opcode != OP_ARG))
252                         continue;
253
254                 /* we dont allocate I1 to registers because there is no simply way to sign extend 
255                  * 8bit quantities in caller saved registers on x86 */
256                 if (is_regsize_var (ins->inst_vtype) || (ins->inst_vtype->type == MONO_TYPE_BOOLEAN) || 
257                     (ins->inst_vtype->type == MONO_TYPE_U1) || (ins->inst_vtype->type == MONO_TYPE_U2)||
258                     (ins->inst_vtype->type == MONO_TYPE_I2) || (ins->inst_vtype->type == MONO_TYPE_CHAR)) {
259                         g_assert (MONO_VARINFO (cfg, i)->reg == -1);
260                         g_assert (i == vmv->idx);
261                         vars = g_list_prepend (vars, vmv);
262                 }
263         }
264
265         vars = mono_varlist_sort (cfg, vars, 0);
266
267         return vars;
268 }
269
270 GList *
271 mono_arch_get_global_int_regs (MonoCompile *cfg)
272 {
273         GList *regs = NULL;
274
275         /* we can use 3 registers for global allocation */
276         regs = g_list_prepend (regs, (gpointer)X86_EBX);
277         regs = g_list_prepend (regs, (gpointer)X86_ESI);
278         regs = g_list_prepend (regs, (gpointer)X86_EDI);
279
280         return regs;
281 }
282
283 /*
284  * mono_arch_regalloc_cost:
285  *
286  *  Return the cost, in number of memory references, of the action of 
287  * allocating the variable VMV into a register during global register
288  * allocation.
289  */
290 guint32
291 mono_arch_regalloc_cost (MonoCompile *cfg, MonoMethodVar *vmv)
292 {
293         MonoInst *ins = cfg->varinfo [vmv->idx];
294
295         if (cfg->method->save_lmf)
296                 /* The register is already saved */
297                 return (ins->opcode == OP_ARG) ? 1 : 0;
298         else
299                 /* push+pop+possible load if it is an argument */
300                 return (ins->opcode == OP_ARG) ? 3 : 2;
301 }
302  
303 /*
304  * Set var information according to the calling convention. X86 version.
305  * The locals var stuff should most likely be split in another method.
306  */
307 void
308 mono_arch_allocate_vars (MonoCompile *m)
309 {
310         MonoMethodSignature *sig;
311         MonoMethodHeader *header;
312         MonoInst *inst;
313         int i, offset, size, align, curinst;
314
315         header = ((MonoMethodNormal *)m->method)->header;
316
317         sig = m->method->signature;
318
319         offset = 8;
320         curinst = 0;
321         if (MONO_TYPE_ISSTRUCT (sig->ret)) {
322                 m->ret->opcode = OP_REGOFFSET;
323                 m->ret->inst_basereg = X86_EBP;
324                 m->ret->inst_offset = offset;
325                 offset += sizeof (gpointer);
326         } else {
327                 /* FIXME: handle long and FP values */
328                 switch (sig->ret->type) {
329                 case MONO_TYPE_VOID:
330                         break;
331                 default:
332                         m->ret->opcode = OP_REGVAR;
333                         m->ret->inst_c0 = X86_EAX;
334                         break;
335                 }
336         }
337         if (sig->hasthis) {
338                 inst = m->varinfo [curinst];
339                 if (inst->opcode != OP_REGVAR) {
340                         inst->opcode = OP_REGOFFSET;
341                         inst->inst_basereg = X86_EBP;
342                 }
343                 inst->inst_offset = offset;
344                 offset += sizeof (gpointer);
345                 curinst++;
346         }
347
348         if (sig->call_convention == MONO_CALL_VARARG) {
349                 m->sig_cookie = offset;
350                 offset += sizeof (gpointer);
351         }
352
353         for (i = 0; i < sig->param_count; ++i) {
354                 inst = m->varinfo [curinst];
355                 if (inst->opcode != OP_REGVAR) {
356                         inst->opcode = OP_REGOFFSET;
357                         inst->inst_basereg = X86_EBP;
358                 }
359                 inst->inst_offset = offset;
360                 size = mono_type_size (sig->params [i], &align);
361                 size += 4 - 1;
362                 size &= ~(4 - 1);
363                 offset += size;
364                 curinst++;
365         }
366
367         offset = 0;
368
369         /* reserve space to save LMF and caller saved registers */
370
371         if (m->method->save_lmf) {
372                 offset += sizeof (MonoLMF);
373         } else {
374                 if (m->used_int_regs & (1 << X86_EBX)) {
375                         offset += 4;
376                 }
377
378                 if (m->used_int_regs & (1 << X86_EDI)) {
379                         offset += 4;
380                 }
381
382                 if (m->used_int_regs & (1 << X86_ESI)) {
383                         offset += 4;
384                 }
385         }
386
387         for (i = curinst; i < m->num_varinfo; ++i) {
388                 inst = m->varinfo [i];
389
390                 if ((inst->flags & MONO_INST_IS_DEAD) || inst->opcode == OP_REGVAR)
391                         continue;
392
393                 /* inst->unused indicates native sized value types, this is used by the
394                 * pinvoke wrappers when they call functions returning structure */
395                 if (inst->unused && MONO_TYPE_ISSTRUCT (inst->inst_vtype) && inst->inst_vtype->type != MONO_TYPE_TYPEDBYREF)
396                         size = mono_class_native_size (inst->inst_vtype->data.klass, &align);
397                 else
398                         size = mono_type_size (inst->inst_vtype, &align);
399
400                 offset += size;
401                 offset += align - 1;
402                 offset &= ~(align - 1);
403                 inst->opcode = OP_REGOFFSET;
404                 inst->inst_basereg = X86_EBP;
405                 inst->inst_offset = -offset;
406                 //g_print ("allocating local %d to %d\n", i, -offset);
407         }
408         offset += (MONO_ARCH_FRAME_ALIGNMENT - 1);
409         offset &= ~(MONO_ARCH_FRAME_ALIGNMENT - 1);
410
411         /* change sign? */
412         m->stack_offset = -offset;
413 }
414
415 /* Fixme: we need an alignment solution for enter_method and mono_arch_call_opcode,
416  * currently alignment in mono_arch_call_opcode is computed without arch_get_argument_info 
417  */
418
419 /* 
420  * take the arguments and generate the arch-specific
421  * instructions to properly call the function in call.
422  * This includes pushing, moving arguments to the right register
423  * etc.
424  * Issue: who does the spilling if needed, and when?
425  */
426 MonoCallInst*
427 mono_arch_call_opcode (MonoCompile *cfg, MonoBasicBlock* bb, MonoCallInst *call, int is_virtual) {
428         MonoInst *arg, *in;
429         MonoMethodSignature *sig;
430         int i, n, stack_size, type;
431         MonoType *ptype;
432
433         stack_size = 0;
434         /* add the vararg cookie before the non-implicit args */
435         if (call->signature->call_convention == MONO_CALL_VARARG) {
436                 MonoInst *sig_arg;
437                 /* FIXME: Add support for signature tokens to AOT */
438                 cfg->disable_aot = TRUE;
439                 MONO_INST_NEW (cfg, arg, OP_OUTARG);
440                 MONO_INST_NEW (cfg, sig_arg, OP_ICONST);
441                 sig_arg->inst_p0 = call->signature;
442                 arg->inst_left = sig_arg;
443                 arg->type = STACK_PTR;
444                 /* prepend, so they get reversed */
445                 arg->next = call->out_args;
446                 call->out_args = arg;
447                 stack_size += sizeof (gpointer);
448         }
449         sig = call->signature;
450         n = sig->param_count + sig->hasthis;
451
452         if (sig->ret && MONO_TYPE_ISSTRUCT (sig->ret))
453                 stack_size += sizeof (gpointer);
454         for (i = 0; i < n; ++i) {
455                 if (is_virtual && i == 0) {
456                         /* the argument will be attached to the call instrucion */
457                         in = call->args [i];
458                         stack_size += 4;
459                 } else {
460                         MONO_INST_NEW (cfg, arg, OP_OUTARG);
461                         in = call->args [i];
462                         arg->cil_code = in->cil_code;
463                         arg->inst_left = in;
464                         arg->type = in->type;
465                         /* prepend, so they get reversed */
466                         arg->next = call->out_args;
467                         call->out_args = arg;
468                         if (i >= sig->hasthis) {
469                                 ptype = sig->params [i - sig->hasthis];
470                                 if (ptype->byref)
471                                         type = MONO_TYPE_U;
472                                 else
473                                         type = ptype->type;
474 handle_enum:
475                                 /* FIXME: validate arguments... */
476                                 switch (type) {
477                                 case MONO_TYPE_I:
478                                 case MONO_TYPE_U:
479                                 case MONO_TYPE_BOOLEAN:
480                                 case MONO_TYPE_CHAR:
481                                 case MONO_TYPE_I1:
482                                 case MONO_TYPE_U1:
483                                 case MONO_TYPE_I2:
484                                 case MONO_TYPE_U2:
485                                 case MONO_TYPE_I4:
486                                 case MONO_TYPE_U4:
487                                 case MONO_TYPE_STRING:
488                                 case MONO_TYPE_CLASS:
489                                 case MONO_TYPE_OBJECT:
490                                 case MONO_TYPE_PTR:
491                                 case MONO_TYPE_FNPTR:
492                                 case MONO_TYPE_ARRAY:
493                                 case MONO_TYPE_SZARRAY:
494                                         stack_size += 4;
495                                         break;
496                                 case MONO_TYPE_I8:
497                                 case MONO_TYPE_U8:
498                                         stack_size += 8;
499                                         break;
500                                 case MONO_TYPE_R4:
501                                         stack_size += 4;
502                                         arg->opcode = OP_OUTARG_R4;
503                                         break;
504                                 case MONO_TYPE_R8:
505                                         stack_size += 8;
506                                         arg->opcode = OP_OUTARG_R8;
507                                         break;
508                                 case MONO_TYPE_VALUETYPE:
509                                         if (MONO_TYPE_ISSTRUCT (ptype)) {
510                                                 int size;
511                                                 if (sig->pinvoke) 
512                                                         size = mono_type_native_stack_size (&in->klass->byval_arg, NULL);
513                                                 else 
514                                                         size = mono_type_stack_size (&in->klass->byval_arg, NULL);
515
516                                                 stack_size += size;
517                                                 arg->opcode = OP_OUTARG_VT;
518                                                 arg->klass = in->klass;
519                                                 arg->unused = sig->pinvoke;
520                                                 arg->inst_imm = size; 
521                                         } else {
522                                                 type = ptype->data.klass->enum_basetype->type;
523                                                 goto handle_enum;
524                                         }
525                                         break;
526                                 case MONO_TYPE_TYPEDBYREF:
527                                         stack_size += sizeof (MonoTypedRef);
528                                         arg->opcode = OP_OUTARG_VT;
529                                         arg->klass = in->klass;
530                                         arg->unused = sig->pinvoke;
531                                         arg->inst_imm = sizeof (MonoTypedRef); 
532                                         break;
533                                 case MONO_TYPE_GENERICINST:
534                                         type = ptype->data.generic_inst->generic_type->type;
535                                         goto handle_enum;
536
537                                 default:
538                                         g_error ("unknown type 0x%02x in mono_arch_call_opcode\n", type);
539                                 }
540                         } else {
541                                 /* the this argument */
542                                 stack_size += 4;
543                         }
544                 }
545         }
546         /* if the function returns a struct, the called method already does a ret $0x4 */
547         if (sig->ret && MONO_TYPE_ISSTRUCT (sig->ret))
548                 stack_size -= 4;
549         call->stack_usage = stack_size;
550         /* 
551          * should set more info in call, such as the stack space
552          * used by the args that needs to be added back to esp
553          */
554
555         return call;
556 }
557
558 /*
559  * Allow tracing to work with this interface (with an optional argument)
560  */
561
562 /*
563  * This may be needed on some archs or for debugging support.
564  */
565 void
566 mono_arch_instrument_mem_needs (MonoMethod *method, int *stack, int *code)
567 {
568         /* no stack room needed now (may be needed for FASTCALL-trace support) */
569         *stack = 0;
570         /* split prolog-epilog requirements? */
571         *code = 50; /* max bytes needed: check this number */
572 }
573
574 void*
575 mono_arch_instrument_prolog (MonoCompile *cfg, void *func, void *p, gboolean enable_arguments)
576 {
577         guchar *code = p;
578
579         /* if some args are passed in registers, we need to save them here */
580         x86_push_reg (code, X86_EBP);
581         mono_add_patch_info (cfg, code-cfg->native_code, MONO_PATCH_INFO_METHODCONST, cfg->method);
582         x86_push_imm (code, cfg->method);
583         mono_add_patch_info (cfg, code-cfg->native_code, MONO_PATCH_INFO_ABS, func);
584         x86_call_code (code, 0);
585         x86_alu_reg_imm (code, X86_ADD, X86_ESP, 8);
586
587         return code;
588 }
589
590 enum {
591         SAVE_NONE,
592         SAVE_STRUCT,
593         SAVE_EAX,
594         SAVE_EAX_EDX,
595         SAVE_FP
596 };
597
598 void*
599 mono_arch_instrument_epilog (MonoCompile *cfg, void *func, void *p, gboolean enable_arguments)
600 {
601         guchar *code = p;
602         int arg_size = 0, save_mode = SAVE_NONE;
603         MonoMethod *method = cfg->method;
604         int rtype = method->signature->ret->type;
605         
606 handle_enum:
607         switch (rtype) {
608         case MONO_TYPE_VOID:
609                 /* special case string .ctor icall */
610                 if (strcmp (".ctor", method->name) && method->klass == mono_defaults.string_class)
611                         save_mode = SAVE_EAX;
612                 else
613                         save_mode = SAVE_NONE;
614                 break;
615         case MONO_TYPE_I8:
616         case MONO_TYPE_U8:
617                 save_mode = SAVE_EAX_EDX;
618                 break;
619         case MONO_TYPE_R4:
620         case MONO_TYPE_R8:
621                 save_mode = SAVE_FP;
622                 break;
623         case MONO_TYPE_VALUETYPE:
624                 if (method->signature->ret->data.klass->enumtype) {
625                         rtype = method->signature->ret->data.klass->enum_basetype->type;
626                         goto handle_enum;
627                 }
628                 save_mode = SAVE_STRUCT;
629                 break;
630         default:
631                 save_mode = SAVE_EAX;
632                 break;
633         }
634
635         switch (save_mode) {
636         case SAVE_EAX_EDX:
637                 x86_push_reg (code, X86_EDX);
638                 x86_push_reg (code, X86_EAX);
639                 if (enable_arguments) {
640                         x86_push_reg (code, X86_EDX);
641                         x86_push_reg (code, X86_EAX);
642                         arg_size = 8;
643                 }
644                 break;
645         case SAVE_EAX:
646                 x86_push_reg (code, X86_EAX);
647                 if (enable_arguments) {
648                         x86_push_reg (code, X86_EAX);
649                         arg_size = 4;
650                 }
651                 break;
652         case SAVE_FP:
653                 x86_alu_reg_imm (code, X86_SUB, X86_ESP, 8);
654                 x86_fst_membase (code, X86_ESP, 0, TRUE, TRUE);
655                 if (enable_arguments) {
656                         x86_alu_reg_imm (code, X86_SUB, X86_ESP, 8);
657                         x86_fst_membase (code, X86_ESP, 0, TRUE, TRUE);
658                         arg_size = 8;
659                 }
660                 break;
661         case SAVE_STRUCT:
662                 if (enable_arguments) {
663                         x86_push_membase (code, X86_EBP, 8);
664                         arg_size = 4;
665                 }
666                 break;
667         case SAVE_NONE:
668         default:
669                 break;
670         }
671
672
673         mono_add_patch_info (cfg, code-cfg->native_code, MONO_PATCH_INFO_METHODCONST, method);
674         x86_push_imm (code, method);
675         mono_add_patch_info (cfg, code-cfg->native_code, MONO_PATCH_INFO_ABS, func);
676         x86_call_code (code, 0);
677         x86_alu_reg_imm (code, X86_ADD, X86_ESP, arg_size + 4);
678
679         switch (save_mode) {
680         case SAVE_EAX_EDX:
681                 x86_pop_reg (code, X86_EAX);
682                 x86_pop_reg (code, X86_EDX);
683                 break;
684         case SAVE_EAX:
685                 x86_pop_reg (code, X86_EAX);
686                 break;
687         case SAVE_FP:
688                 x86_fld_membase (code, X86_ESP, 0, TRUE);
689                 x86_alu_reg_imm (code, X86_ADD, X86_ESP, 8);
690                 break;
691         case SAVE_NONE:
692         default:
693                 break;
694         }
695
696         return code;
697 }
698
699 #define EMIT_COND_BRANCH(ins,cond,sign) \
700 if (ins->flags & MONO_INST_BRLABEL) { \
701         if (ins->inst_i0->inst_c0) { \
702                 x86_branch (code, cond, cfg->native_code + ins->inst_i0->inst_c0, sign); \
703         } else { \
704                 mono_add_patch_info (cfg, code - cfg->native_code, MONO_PATCH_INFO_LABEL, ins->inst_i0); \
705                 x86_branch32 (code, cond, 0, sign); \
706         } \
707 } else { \
708         if (ins->inst_true_bb->native_offset) { \
709                 x86_branch (code, cond, cfg->native_code + ins->inst_true_bb->native_offset, sign); \
710         } else { \
711                 mono_add_patch_info (cfg, code - cfg->native_code, MONO_PATCH_INFO_BB, ins->inst_true_bb); \
712                 if ((cfg->opt & MONO_OPT_BRANCH) && \
713                     x86_is_imm8 (ins->inst_true_bb->max_offset - cpos)) \
714                         x86_branch8 (code, cond, 0, sign); \
715                 else \
716                         x86_branch32 (code, cond, 0, sign); \
717         } \
718 }
719
720 /* emit an exception if condition is fail */
721 #define EMIT_COND_SYSTEM_EXCEPTION(cond,signed,exc_name)            \
722         do {                                                        \
723                 mono_add_patch_info (cfg, code - cfg->native_code,   \
724                                     MONO_PATCH_INFO_EXC, exc_name);  \
725                 x86_branch32 (code, cond, 0, signed);               \
726         } while (0); 
727
728 #define EMIT_FPCOMPARE(code) do { \
729         x86_fcompp (code); \
730         x86_fnstsw (code); \
731 } while (0); 
732
733 /* FIXME: Add more instructions */
734 #define INST_IGNORES_CFLAGS(ins) (((ins)->opcode == CEE_BR) || ((ins)->opcode == OP_STORE_MEMBASE_IMM))
735
736 static void
737 peephole_pass (MonoCompile *cfg, MonoBasicBlock *bb)
738 {
739         MonoInst *ins, *last_ins = NULL;
740         ins = bb->code;
741
742         while (ins) {
743
744                 switch (ins->opcode) {
745                 case OP_ICONST:
746                         /* reg = 0 -> XOR (reg, reg) */
747                         /* XOR sets cflags on x86, so we cant do it always */
748                         if (ins->inst_c0 == 0 && ins->next && INST_IGNORES_CFLAGS (ins->next)) {
749                                 ins->opcode = CEE_XOR;
750                                 ins->sreg1 = ins->dreg;
751                                 ins->sreg2 = ins->dreg;
752                         }
753                         break;
754                 case OP_MUL_IMM: 
755                         /* remove unnecessary multiplication with 1 */
756                         if (ins->inst_imm == 1) {
757                                 if (ins->dreg != ins->sreg1) {
758                                         ins->opcode = OP_MOVE;
759                                 } else {
760                                         last_ins->next = ins->next;
761                                         ins = ins->next;
762                                         continue;
763                                 }
764                         }
765                         break;
766                 case OP_COMPARE_IMM:
767                         /* OP_COMPARE_IMM (reg, 0) 
768                          * --> 
769                          * OP_X86_TEST_NULL (reg) 
770                          */
771                         if (ins->inst_imm == 0 && ins->next &&
772                             (ins->next->opcode == CEE_BEQ || ins->next->opcode == CEE_BNE_UN ||
773                              ins->next->opcode == OP_CEQ)) {
774                                 ins->opcode = OP_X86_TEST_NULL;
775                         }     
776                         break;
777                 case OP_X86_COMPARE_MEMBASE_IMM:
778                         /* 
779                          * OP_STORE_MEMBASE_REG reg, offset(basereg)
780                          * OP_X86_COMPARE_MEMBASE_IMM offset(basereg), imm
781                          * -->
782                          * OP_STORE_MEMBASE_REG reg, offset(basereg)
783                          * OP_COMPARE_IMM reg, imm
784                          *
785                          * Note: if imm = 0 then OP_COMPARE_IMM replaced with OP_X86_TEST_NULL
786                          */
787                         if (last_ins && (last_ins->opcode == OP_STOREI4_MEMBASE_REG) &&
788                             ins->inst_basereg == last_ins->inst_destbasereg &&
789                             ins->inst_offset == last_ins->inst_offset) {
790                                         ins->opcode = OP_COMPARE_IMM;
791                                         ins->sreg1 = last_ins->sreg1;
792
793                                         /* check if we can remove cmp reg,0 with test null */
794                                         if (ins->inst_imm == 0 && ins->next &&
795                                                 (ins->next->opcode == CEE_BEQ || ins->next->opcode == CEE_BNE_UN ||
796                                                 ins->next->opcode == OP_CEQ)) {
797                                                 ins->opcode = OP_X86_TEST_NULL;
798                                         }     
799                                 }
800
801                         break;
802                 case OP_LOAD_MEMBASE:
803                 case OP_LOADI4_MEMBASE:
804                         /* 
805                          * Note: if reg1 = reg2 the load op is removed
806                          *
807                          * OP_STORE_MEMBASE_REG reg1, offset(basereg) 
808                          * OP_LOAD_MEMBASE offset(basereg), reg2
809                          * -->
810                          * OP_STORE_MEMBASE_REG reg1, offset(basereg)
811                          * OP_MOVE reg1, reg2
812                          */
813                         if (last_ins && (last_ins->opcode == OP_STOREI4_MEMBASE_REG 
814                                          || last_ins->opcode == OP_STORE_MEMBASE_REG) &&
815                             ins->inst_basereg == last_ins->inst_destbasereg &&
816                             ins->inst_offset == last_ins->inst_offset) {
817                                 if (ins->dreg == last_ins->sreg1) {
818                                         last_ins->next = ins->next;                             
819                                         ins = ins->next;                                
820                                         continue;
821                                 } else {
822                                         //static int c = 0; printf ("MATCHX %s %d\n", cfg->method->name,c++);
823                                         ins->opcode = OP_MOVE;
824                                         ins->sreg1 = last_ins->sreg1;
825                                 }
826
827                         /* 
828                          * Note: reg1 must be different from the basereg in the second load
829                          * Note: if reg1 = reg2 is equal then second load is removed
830                          *
831                          * OP_LOAD_MEMBASE offset(basereg), reg1
832                          * OP_LOAD_MEMBASE offset(basereg), reg2
833                          * -->
834                          * OP_LOAD_MEMBASE offset(basereg), reg1
835                          * OP_MOVE reg1, reg2
836                          */
837                         } if (last_ins && (last_ins->opcode == OP_LOADI4_MEMBASE
838                                            || last_ins->opcode == OP_LOAD_MEMBASE) &&
839                               ins->inst_basereg != last_ins->dreg &&
840                               ins->inst_basereg == last_ins->inst_basereg &&
841                               ins->inst_offset == last_ins->inst_offset) {
842
843                                 if (ins->dreg == last_ins->dreg) {
844                                         last_ins->next = ins->next;                             
845                                         ins = ins->next;                                
846                                         continue;
847                                 } else {
848                                         ins->opcode = OP_MOVE;
849                                         ins->sreg1 = last_ins->dreg;
850                                 }
851
852                                 //g_assert_not_reached ();
853
854 #if 0
855                         /* 
856                          * OP_STORE_MEMBASE_IMM imm, offset(basereg) 
857                          * OP_LOAD_MEMBASE offset(basereg), reg
858                          * -->
859                          * OP_STORE_MEMBASE_IMM imm, offset(basereg) 
860                          * OP_ICONST reg, imm
861                          */
862                         } else if (last_ins && (last_ins->opcode == OP_STOREI4_MEMBASE_IMM
863                                                 || last_ins->opcode == OP_STORE_MEMBASE_IMM) &&
864                                    ins->inst_basereg == last_ins->inst_destbasereg &&
865                                    ins->inst_offset == last_ins->inst_offset) {
866                                 //static int c = 0; printf ("MATCHX %s %d\n", cfg->method->name,c++);
867                                 ins->opcode = OP_ICONST;
868                                 ins->inst_c0 = last_ins->inst_imm;
869                                 g_assert_not_reached (); // check this rule
870 #endif
871                         }
872                         break;
873                 case OP_LOADU1_MEMBASE:
874                 case OP_LOADI1_MEMBASE:
875                         /* 
876                          * Note: if reg1 = reg2 the load op is removed
877                          *
878                          * OP_STORE_MEMBASE_REG reg1, offset(basereg) 
879                          * OP_LOAD_MEMBASE offset(basereg), reg2
880                          * -->
881                          * OP_STORE_MEMBASE_REG reg1, offset(basereg)
882                          * OP_MOVE reg1, reg2
883                          */
884                         if (last_ins && (last_ins->opcode == OP_STOREI1_MEMBASE_REG) &&
885                                         ins->inst_basereg == last_ins->inst_destbasereg &&
886                                         ins->inst_offset == last_ins->inst_offset) {
887                                 if (ins->dreg == last_ins->sreg1) {
888                                         last_ins->next = ins->next;                             
889                                         ins = ins->next;                                
890                                         continue;
891                                 } else {
892                                         //static int c = 0; printf ("MATCHX %s %d\n", cfg->method->name,c++);
893                                         ins->opcode = OP_MOVE;
894                                         ins->sreg1 = last_ins->sreg1;
895                                 }
896                         }
897                         break;
898                 case OP_LOADU2_MEMBASE:
899                 case OP_LOADI2_MEMBASE:
900                         /* 
901                          * Note: if reg1 = reg2 the load op is removed
902                          *
903                          * OP_STORE_MEMBASE_REG reg1, offset(basereg) 
904                          * OP_LOAD_MEMBASE offset(basereg), reg2
905                          * -->
906                          * OP_STORE_MEMBASE_REG reg1, offset(basereg)
907                          * OP_MOVE reg1, reg2
908                          */
909                         if (last_ins && (last_ins->opcode == OP_STOREI2_MEMBASE_REG) &&
910                                         ins->inst_basereg == last_ins->inst_destbasereg &&
911                                         ins->inst_offset == last_ins->inst_offset) {
912                                 if (ins->dreg == last_ins->sreg1) {
913                                         last_ins->next = ins->next;                             
914                                         ins = ins->next;                                
915                                         continue;
916                                 } else {
917                                         //static int c = 0; printf ("MATCHX %s %d\n", cfg->method->name,c++);
918                                         ins->opcode = OP_MOVE;
919                                         ins->sreg1 = last_ins->sreg1;
920                                 }
921                         }
922                         break;
923                 case CEE_CONV_I4:
924                 case CEE_CONV_U4:
925                 case OP_MOVE:
926                         /*
927                          * Removes:
928                          *
929                          * OP_MOVE reg, reg 
930                          */
931                         if (ins->dreg == ins->sreg1) {
932                                 if (last_ins)
933                                         last_ins->next = ins->next;                             
934                                 ins = ins->next;
935                                 continue;
936                         }
937                         /* 
938                          * Removes:
939                          *
940                          * OP_MOVE sreg, dreg 
941                          * OP_MOVE dreg, sreg
942                          */
943                         if (last_ins && last_ins->opcode == OP_MOVE &&
944                             ins->sreg1 == last_ins->dreg &&
945                             ins->dreg == last_ins->sreg1) {
946                                 last_ins->next = ins->next;                             
947                                 ins = ins->next;                                
948                                 continue;
949                         }
950                         break;
951                 }
952                 last_ins = ins;
953                 ins = ins->next;
954         }
955         bb->last_ins = last_ins;
956 }
957
958 static const int 
959 branch_cc_table [] = {
960         X86_CC_EQ, X86_CC_GE, X86_CC_GT, X86_CC_LE, X86_CC_LT,
961         X86_CC_NE, X86_CC_GE, X86_CC_GT, X86_CC_LE, X86_CC_LT,
962         X86_CC_O, X86_CC_NO, X86_CC_C, X86_CC_NC
963 };
964
965 #define DEBUG(a) if (cfg->verbose_level > 1) a
966 //#define DEBUG(a)
967
968 /*
969  * returns the offset used by spillvar. It allocates a new
970  * spill variable if necessary. 
971  */
972 static int
973 mono_spillvar_offset (MonoCompile *cfg, int spillvar)
974 {
975         MonoSpillInfo **si, *info;
976         int i = 0;
977
978         si = &cfg->spill_info; 
979         
980         while (i <= spillvar) {
981
982                 if (!*si) {
983                         *si = info = mono_mempool_alloc (cfg->mempool, sizeof (MonoSpillInfo));
984                         info->next = NULL;
985                         cfg->stack_offset -= sizeof (gpointer);
986                         info->offset = cfg->stack_offset;
987                 }
988
989                 if (i == spillvar)
990                         return (*si)->offset;
991
992                 i++;
993                 si = &(*si)->next;
994         }
995
996         g_assert_not_reached ();
997         return 0;
998 }
999
1000 /*
1001  * returns the offset used by spillvar. It allocates a new
1002  * spill float variable if necessary. 
1003  * (same as mono_spillvar_offset but for float)
1004  */
1005 static int
1006 mono_spillvar_offset_float (MonoCompile *cfg, int spillvar)
1007 {
1008         MonoSpillInfo **si, *info;
1009         int i = 0;
1010
1011         si = &cfg->spill_info_float; 
1012         
1013         while (i <= spillvar) {
1014
1015                 if (!*si) {
1016                         *si = info = mono_mempool_alloc (cfg->mempool, sizeof (MonoSpillInfo));
1017                         info->next = NULL;
1018                         cfg->stack_offset -= sizeof (double);
1019                         info->offset = cfg->stack_offset;
1020                 }
1021
1022                 if (i == spillvar)
1023                         return (*si)->offset;
1024
1025                 i++;
1026                 si = &(*si)->next;
1027         }
1028
1029         g_assert_not_reached ();
1030         return 0;
1031 }
1032
1033 /*
1034  * Creates a store for spilled floating point items
1035  */
1036 static MonoInst*
1037 create_spilled_store_float (MonoCompile *cfg, int spill, int reg, MonoInst *ins)
1038 {
1039         MonoInst *store;
1040         MONO_INST_NEW (cfg, store, OP_STORER8_MEMBASE_REG);
1041         store->sreg1 = reg;
1042         store->inst_destbasereg = X86_EBP;
1043         store->inst_offset = mono_spillvar_offset_float (cfg, spill);
1044
1045         DEBUG (g_print ("SPILLED FLOAT STORE (%d at 0x%08x(%%sp)) (from %d)\n", spill, store->inst_offset, reg));
1046         return store;
1047 }
1048
1049 /*
1050  * Creates a load for spilled floating point items 
1051  */
1052 static MonoInst*
1053 create_spilled_load_float (MonoCompile *cfg, int spill, int reg, MonoInst *ins)
1054 {
1055         MonoInst *load;
1056         MONO_INST_NEW (cfg, load, OP_LOADR8_SPILL_MEMBASE);
1057         load->dreg = reg;
1058         load->inst_basereg = X86_EBP;
1059         load->inst_offset = mono_spillvar_offset_float (cfg, spill);
1060
1061         DEBUG (g_print ("SPILLED FLOAT LOAD (%d at 0x%08x(%%sp)) (from %d)\n", spill, load->inst_offset, reg));
1062         return load;
1063 }
1064
1065 #define reg_is_freeable(r) ((r) >= 0 && (r) <= 7 && X86_IS_CALLEE ((r)))
1066
1067 typedef struct {
1068         int born_in;
1069         int killed_in;
1070         int last_use;
1071         int prev_use;
1072         int flags;              /* used to track fp spill/load */
1073 } RegTrack;
1074
1075 static const char*const * ins_spec = pentium_desc;
1076
1077 static void
1078 print_ins (int i, MonoInst *ins)
1079 {
1080         const char *spec = ins_spec [ins->opcode];
1081         g_print ("\t%-2d %s", i, mono_inst_name (ins->opcode));
1082         if (spec [MONO_INST_DEST]) {
1083                 if (ins->dreg >= MONO_MAX_IREGS)
1084                         g_print (" R%d <-", ins->dreg);
1085                 else
1086                         g_print (" %s <-", mono_arch_regname (ins->dreg));
1087         }
1088         if (spec [MONO_INST_SRC1]) {
1089                 if (ins->sreg1 >= MONO_MAX_IREGS)
1090                         g_print (" R%d", ins->sreg1);
1091                 else
1092                         g_print (" %s", mono_arch_regname (ins->sreg1));
1093         }
1094         if (spec [MONO_INST_SRC2]) {
1095                 if (ins->sreg2 >= MONO_MAX_IREGS)
1096                         g_print (" R%d", ins->sreg2);
1097                 else
1098                         g_print (" %s", mono_arch_regname (ins->sreg2));
1099         }
1100         if (spec [MONO_INST_CLOB])
1101                 g_print (" clobbers: %c", spec [MONO_INST_CLOB]);
1102         g_print ("\n");
1103 }
1104
1105 static void
1106 print_regtrack (RegTrack *t, int num)
1107 {
1108         int i;
1109         char buf [32];
1110         const char *r;
1111         
1112         for (i = 0; i < num; ++i) {
1113                 if (!t [i].born_in)
1114                         continue;
1115                 if (i >= MONO_MAX_IREGS) {
1116                         g_snprintf (buf, sizeof(buf), "R%d", i);
1117                         r = buf;
1118                 } else
1119                         r = mono_arch_regname (i);
1120                 g_print ("liveness: %s [%d - %d]\n", r, t [i].born_in, t[i].last_use);
1121         }
1122 }
1123
1124 typedef struct InstList InstList;
1125
1126 struct InstList {
1127         InstList *prev;
1128         InstList *next;
1129         MonoInst *data;
1130 };
1131
1132 static inline InstList*
1133 inst_list_prepend (MonoMemPool *pool, InstList *list, MonoInst *data)
1134 {
1135         InstList *item = mono_mempool_alloc (pool, sizeof (InstList));
1136         item->data = data;
1137         item->prev = NULL;
1138         item->next = list;
1139         if (list)
1140                 list->prev = item;
1141         return item;
1142 }
1143
1144 /*
1145  * Force the spilling of the variable in the symbolic register 'reg'.
1146  */
1147 static int
1148 get_register_force_spilling (MonoCompile *cfg, InstList *item, MonoInst *ins, int reg)
1149 {
1150         MonoInst *load;
1151         int i, sel, spill;
1152         
1153         sel = cfg->rs->iassign [reg];
1154         /*i = cfg->rs->isymbolic [sel];
1155         g_assert (i == reg);*/
1156         i = reg;
1157         spill = ++cfg->spill_count;
1158         cfg->rs->iassign [i] = -spill - 1;
1159         mono_regstate_free_int (cfg->rs, sel);
1160         /* we need to create a spill var and insert a load to sel after the current instruction */
1161         MONO_INST_NEW (cfg, load, OP_LOAD_MEMBASE);
1162         load->dreg = sel;
1163         load->inst_basereg = X86_EBP;
1164         load->inst_offset = mono_spillvar_offset (cfg, spill);
1165         if (item->prev) {
1166                 while (ins->next != item->prev->data)
1167                         ins = ins->next;
1168         }
1169         load->next = ins->next;
1170         ins->next = load;
1171         DEBUG (g_print ("SPILLED LOAD (%d at 0x%08x(%%ebp)) R%d (freed %s)\n", spill, load->inst_offset, i, mono_arch_regname (sel)));
1172         i = mono_regstate_alloc_int (cfg->rs, 1 << sel);
1173         g_assert (i == sel);
1174
1175         return sel;
1176 }
1177
1178 static int
1179 get_register_spilling (MonoCompile *cfg, InstList *item, MonoInst *ins, guint32 regmask, int reg)
1180 {
1181         MonoInst *load;
1182         int i, sel, spill;
1183
1184         DEBUG (g_print ("start regmask to assign R%d: 0x%08x (R%d <- R%d R%d)\n", reg, regmask, ins->dreg, ins->sreg1, ins->sreg2));
1185         /* exclude the registers in the current instruction */
1186         if (reg != ins->sreg1 && (reg_is_freeable (ins->sreg1) || (ins->sreg1 >= MONO_MAX_IREGS && cfg->rs->iassign [ins->sreg1] >= 0))) {
1187                 if (ins->sreg1 >= MONO_MAX_IREGS)
1188                         regmask &= ~ (1 << cfg->rs->iassign [ins->sreg1]);
1189                 else
1190                         regmask &= ~ (1 << ins->sreg1);
1191                 DEBUG (g_print ("excluding sreg1 %s\n", mono_arch_regname (ins->sreg1)));
1192         }
1193         if (reg != ins->sreg2 && (reg_is_freeable (ins->sreg2) || (ins->sreg2 >= MONO_MAX_IREGS && cfg->rs->iassign [ins->sreg2] >= 0))) {
1194                 if (ins->sreg2 >= MONO_MAX_IREGS)
1195                         regmask &= ~ (1 << cfg->rs->iassign [ins->sreg2]);
1196                 else
1197                         regmask &= ~ (1 << ins->sreg2);
1198                 DEBUG (g_print ("excluding sreg2 %s %d\n", mono_arch_regname (ins->sreg2), ins->sreg2));
1199         }
1200         if (reg != ins->dreg && reg_is_freeable (ins->dreg)) {
1201                 regmask &= ~ (1 << ins->dreg);
1202                 DEBUG (g_print ("excluding dreg %s\n", mono_arch_regname (ins->dreg)));
1203         }
1204
1205         DEBUG (g_print ("available regmask: 0x%08x\n", regmask));
1206         g_assert (regmask); /* need at least a register we can free */
1207         sel = -1;
1208         /* we should track prev_use and spill the register that's farther */
1209         for (i = 0; i < MONO_MAX_IREGS; ++i) {
1210                 if (regmask & (1 << i)) {
1211                         sel = i;
1212                         DEBUG (g_print ("selected register %s has assignment %d\n", mono_arch_regname (sel), cfg->rs->iassign [sel]));
1213                         break;
1214                 }
1215         }
1216         i = cfg->rs->isymbolic [sel];
1217         spill = ++cfg->spill_count;
1218         cfg->rs->iassign [i] = -spill - 1;
1219         mono_regstate_free_int (cfg->rs, sel);
1220         /* we need to create a spill var and insert a load to sel after the current instruction */
1221         MONO_INST_NEW (cfg, load, OP_LOAD_MEMBASE);
1222         load->dreg = sel;
1223         load->inst_basereg = X86_EBP;
1224         load->inst_offset = mono_spillvar_offset (cfg, spill);
1225         if (item->prev) {
1226                 while (ins->next != item->prev->data)
1227                         ins = ins->next;
1228         }
1229         load->next = ins->next;
1230         ins->next = load;
1231         DEBUG (g_print ("SPILLED LOAD (%d at 0x%08x(%%ebp)) R%d (freed %s)\n", spill, load->inst_offset, i, mono_arch_regname (sel)));
1232         i = mono_regstate_alloc_int (cfg->rs, 1 << sel);
1233         g_assert (i == sel);
1234         
1235         return sel;
1236 }
1237
1238 static MonoInst*
1239 create_copy_ins (MonoCompile *cfg, int dest, int src, MonoInst *ins)
1240 {
1241         MonoInst *copy;
1242         MONO_INST_NEW (cfg, copy, OP_MOVE);
1243         copy->dreg = dest;
1244         copy->sreg1 = src;
1245         if (ins) {
1246                 copy->next = ins->next;
1247                 ins->next = copy;
1248         }
1249         DEBUG (g_print ("\tforced copy from %s to %s\n", mono_arch_regname (src), mono_arch_regname (dest)));
1250         return copy;
1251 }
1252
1253 static MonoInst*
1254 create_spilled_store (MonoCompile *cfg, int spill, int reg, int prev_reg, MonoInst *ins)
1255 {
1256         MonoInst *store;
1257         MONO_INST_NEW (cfg, store, OP_STORE_MEMBASE_REG);
1258         store->sreg1 = reg;
1259         store->inst_destbasereg = X86_EBP;
1260         store->inst_offset = mono_spillvar_offset (cfg, spill);
1261         if (ins) {
1262                 store->next = ins->next;
1263                 ins->next = store;
1264         }
1265         DEBUG (g_print ("SPILLED STORE (%d at 0x%08x(%%ebp)) R%d (from %s)\n", spill, store->inst_offset, prev_reg, mono_arch_regname (reg)));
1266         return store;
1267 }
1268
1269 static void
1270 insert_before_ins (MonoInst *ins, InstList *item, MonoInst* to_insert)
1271 {
1272         MonoInst *prev;
1273         if (item->next) {
1274                 prev = item->next->data;
1275
1276                 while (prev->next != ins)
1277                         prev = prev->next;
1278                 to_insert->next = ins;
1279                 prev->next = to_insert;
1280         } else {
1281                 to_insert->next = ins;
1282         }
1283         /* 
1284          * needed otherwise in the next instruction we can add an ins to the 
1285          * end and that would get past this instruction.
1286          */
1287         item->data = to_insert; 
1288 }
1289
1290
1291 #if  0
1292 static int
1293 alloc_int_reg (MonoCompile *cfg, InstList *curinst, MonoInst *ins, int sym_reg, guint32 allow_mask)
1294 {
1295         int val = cfg->rs->iassign [sym_reg];
1296         if (val < 0) {
1297                 int spill = 0;
1298                 if (val < -1) {
1299                         /* the register gets spilled after this inst */
1300                         spill = -val -1;
1301                 }
1302                 val = mono_regstate_alloc_int (cfg->rs, allow_mask);
1303                 if (val < 0)
1304                         val = get_register_spilling (cfg, curinst, ins, allow_mask, sym_reg);
1305                 cfg->rs->iassign [sym_reg] = val;
1306                 /* add option to store before the instruction for src registers */
1307                 if (spill)
1308                         create_spilled_store (cfg, spill, val, sym_reg, ins);
1309         }
1310         cfg->rs->isymbolic [val] = sym_reg;
1311         return val;
1312 }
1313 #endif
1314
1315 /* flags used in reginfo->flags */
1316 #define MONO_X86_FP_NEEDS_LOAD_SPILL    1
1317 #define MONO_X86_FP_NEEDS_SPILL                 2
1318 #define MONO_X86_FP_NEEDS_LOAD                  4
1319
1320 /*#include "cprop.c"*/
1321
1322 /*
1323  * Local register allocation.
1324  * We first scan the list of instructions and we save the liveness info of
1325  * each register (when the register is first used, when it's value is set etc.).
1326  * We also reverse the list of instructions (in the InstList list) because assigning
1327  * registers backwards allows for more tricks to be used.
1328  */
1329 void
1330 mono_arch_local_regalloc (MonoCompile *cfg, MonoBasicBlock *bb)
1331 {
1332         MonoInst *ins;
1333         MonoRegState *rs = cfg->rs;
1334         int i, val, fpcount;
1335         RegTrack *reginfo, *reginfof;
1336         RegTrack *reginfo1, *reginfo2, *reginfod;
1337         InstList *tmp, *reversed = NULL;
1338         const char *spec;
1339         guint32 src1_mask, src2_mask, dest_mask;
1340         GList *fspill_list = NULL;
1341         int fspill = 0;
1342
1343         if (!bb->code)
1344                 return;
1345         rs->next_vireg = bb->max_ireg;
1346         rs->next_vfreg = bb->max_freg;
1347         mono_regstate_assign (rs);
1348         reginfo = g_malloc0 (sizeof (RegTrack) * rs->next_vireg);
1349         reginfof = g_malloc0 (sizeof (RegTrack) * rs->next_vfreg);
1350         rs->ifree_mask = X86_CALLEE_REGS;
1351
1352         ins = bb->code;
1353
1354         /*if (cfg->opt & MONO_OPT_COPYPROP)
1355                 local_copy_prop (cfg, ins);*/
1356
1357         i = 1;
1358         fpcount = 0;
1359         DEBUG (g_print ("LOCAL regalloc: basic block: %d\n", bb->block_num));
1360         /* forward pass on the instructions to collect register liveness info */
1361         while (ins) {
1362                 spec = ins_spec [ins->opcode];
1363                 
1364                 DEBUG (print_ins (i, ins));
1365
1366                 if (spec [MONO_INST_SRC1]) {
1367                         if (spec [MONO_INST_SRC1] == 'f') {
1368                                 GList *spill;
1369                                 reginfo1 = reginfof;
1370
1371                                 spill = g_list_first (fspill_list);
1372                                 if (spill && fpcount < MONO_MAX_FREGS) {
1373                                         reginfo1 [ins->sreg1].flags |= MONO_X86_FP_NEEDS_LOAD;
1374                                         fspill_list = g_list_remove (fspill_list, spill->data);
1375                                 } else
1376                                         fpcount--;
1377                         }
1378                         else
1379                                 reginfo1 = reginfo;
1380                         reginfo1 [ins->sreg1].prev_use = reginfo1 [ins->sreg1].last_use;
1381                         reginfo1 [ins->sreg1].last_use = i;
1382                         if (spec [MONO_INST_SRC1] == 'L') {
1383                                 /* The virtual register is allocated sequentially */
1384                                 reginfo1 [ins->sreg1 + 1].prev_use = reginfo1 [ins->sreg1 + 1].last_use;
1385                                 reginfo1 [ins->sreg1 + 1].last_use = i;
1386                                 if (reginfo1 [ins->sreg1 + 1].born_in == 0 || reginfo1 [ins->sreg1 + 1].born_in > i)
1387                                         reginfo1 [ins->sreg1 + 1].born_in = i;
1388                         }
1389                 } else {
1390                         ins->sreg1 = -1;
1391                 }
1392                 if (spec [MONO_INST_SRC2]) {
1393                         if (spec [MONO_INST_SRC2] == 'f') {
1394                                 GList *spill;
1395                                 reginfo2 = reginfof;
1396                                 spill = g_list_first (fspill_list);
1397                                 if (spill) {
1398                                         reginfo2 [ins->sreg2].flags |= MONO_X86_FP_NEEDS_LOAD;
1399                                         fspill_list = g_list_remove (fspill_list, spill->data);
1400                                         if (fpcount >= MONO_MAX_FREGS) {
1401                                                 fspill++;
1402                                                 fspill_list = g_list_prepend (fspill_list, GINT_TO_POINTER(fspill));
1403                                                 reginfo2 [ins->sreg2].flags |= MONO_X86_FP_NEEDS_LOAD_SPILL;
1404                                         }
1405                                 } else
1406                                         fpcount--;
1407                         }
1408                         else
1409                                 reginfo2 = reginfo;
1410                         reginfo2 [ins->sreg2].prev_use = reginfo2 [ins->sreg2].last_use;
1411                         reginfo2 [ins->sreg2].last_use = i;
1412                         if (spec [MONO_INST_SRC2] == 'L') {
1413                                 /* The virtual register is allocated sequentially */
1414                                 reginfo2 [ins->sreg2 + 1].prev_use = reginfo2 [ins->sreg2 + 1].last_use;
1415                                 reginfo2 [ins->sreg2 + 1].last_use = i;
1416                                 if (reginfo2 [ins->sreg2 + 1].born_in == 0 || reginfo2 [ins->sreg2 + 1].born_in > i)
1417                                         reginfo2 [ins->sreg2 + 1].born_in = i;
1418                         }
1419                 } else {
1420                         ins->sreg2 = -1;
1421                 }
1422                 if (spec [MONO_INST_DEST]) {
1423                         if (spec [MONO_INST_DEST] == 'f') {
1424                                 reginfod = reginfof;
1425                                 if (fpcount >= MONO_MAX_FREGS) {
1426                                         reginfod [ins->dreg].flags |= MONO_X86_FP_NEEDS_SPILL;
1427                                         fspill++;
1428                                         fspill_list = g_list_prepend (fspill_list, GINT_TO_POINTER(fspill));
1429                                         fpcount--;
1430                                 }
1431                                 fpcount++;
1432                         }
1433                         else
1434                                 reginfod = reginfo;
1435                         if (spec [MONO_INST_DEST] != 'b') /* it's not just a base register */
1436                                 reginfod [ins->dreg].killed_in = i;
1437                         reginfod [ins->dreg].prev_use = reginfod [ins->dreg].last_use;
1438                         reginfod [ins->dreg].last_use = i;
1439                         if (reginfod [ins->dreg].born_in == 0 || reginfod [ins->dreg].born_in > i)
1440                                 reginfod [ins->dreg].born_in = i;
1441                         if (spec [MONO_INST_DEST] == 'l' || spec [MONO_INST_DEST] == 'L') {
1442                                 /* The virtual register is allocated sequentially */
1443                                 reginfod [ins->dreg + 1].prev_use = reginfod [ins->dreg + 1].last_use;
1444                                 reginfod [ins->dreg + 1].last_use = i;
1445                                 if (reginfod [ins->dreg + 1].born_in == 0 || reginfod [ins->dreg + 1].born_in > i)
1446                                         reginfod [ins->dreg + 1].born_in = i;
1447                         } 
1448                 } else {
1449                         ins->dreg = -1;
1450                 }
1451                 reversed = inst_list_prepend (cfg->mempool, reversed, ins);
1452                 ++i;
1453                 ins = ins->next;
1454         }
1455
1456         // todo: check if we have anything left on fp stack, in verify mode?
1457         fspill = 0;
1458
1459         DEBUG (print_regtrack (reginfo, rs->next_vireg));
1460         DEBUG (print_regtrack (reginfof, rs->next_vfreg));
1461         tmp = reversed;
1462         while (tmp) {
1463                 int prev_dreg, prev_sreg1, prev_sreg2, clob_dreg;
1464                 dest_mask = src1_mask = src2_mask = X86_CALLEE_REGS;
1465                 --i;
1466                 ins = tmp->data;
1467                 spec = ins_spec [ins->opcode];
1468                 prev_dreg = -1;
1469                 clob_dreg = -1;
1470                 DEBUG (g_print ("processing:"));
1471                 DEBUG (print_ins (i, ins));
1472                 if (spec [MONO_INST_CLOB] == 's') {
1473                         if (rs->ifree_mask & (1 << X86_ECX)) {
1474                                 DEBUG (g_print ("\tshortcut assignment of R%d to ECX\n", ins->sreg2));
1475                                 rs->iassign [ins->sreg2] = X86_ECX;
1476                                 rs->isymbolic [X86_ECX] = ins->sreg2;
1477                                 ins->sreg2 = X86_ECX;
1478                                 rs->ifree_mask &= ~ (1 << X86_ECX);
1479                         } else {
1480                                 int need_ecx_spill = TRUE;
1481                                 /* 
1482                                  * we first check if src1/dreg is already assigned a register
1483                                  * and then we force a spill of the var assigned to ECX.
1484                                  */
1485                                 /* the destination register can't be ECX */
1486                                 dest_mask &= ~ (1 << X86_ECX);
1487                                 src1_mask &= ~ (1 << X86_ECX);
1488                                 val = rs->iassign [ins->dreg];
1489                                 /* 
1490                                  * the destination register is already assigned to ECX:
1491                                  * we need to allocate another register for it and then
1492                                  * copy from this to ECX.
1493                                  */
1494                                 if (val == X86_ECX && ins->dreg != ins->sreg2) {
1495                                         int new_dest = mono_regstate_alloc_int (rs, dest_mask);
1496                                         if (new_dest < 0)
1497                                                 new_dest = get_register_spilling (cfg, tmp, ins, dest_mask, ins->dreg);
1498                                         g_assert (new_dest >= 0);
1499                                         DEBUG (g_print ("\tclob:s changing dreg from R%d to %s (val = %d)\n", ins->dreg, mono_arch_regname (new_dest), val));
1500                                         clob_dreg = ins->dreg;
1501                                         ins->dreg = new_dest;
1502                                         create_copy_ins (cfg, X86_ECX, new_dest, ins);
1503                                         need_ecx_spill = FALSE;
1504                                         /*DEBUG (g_print ("\tforced spill of R%d\n", ins->dreg));
1505                                         val = get_register_force_spilling (cfg, tmp, ins, ins->dreg);
1506                                         rs->iassign [ins->dreg] = val;
1507                                         rs->isymbolic [val] = prev_dreg;
1508                                         ins->dreg = val;*/
1509                                 }
1510                                 val = rs->iassign [ins->sreg1];
1511                                 if (val == X86_ECX) {
1512                                         g_assert_not_reached ();
1513                                 } else if (val >= 0) {
1514                                         /* 
1515                                          * the first src reg was already assigned to a register,
1516                                          * we need to copy it to the dest register because the 
1517                                          * shift instruction clobbers the first operand.
1518                                          */
1519                                         MonoInst *copy = create_copy_ins (cfg, ins->dreg, val, NULL);
1520                                         DEBUG (g_print ("\tclob:s moved sreg1 from R%d to R%d\n", val, ins->dreg));
1521                                         insert_before_ins (ins, tmp, copy);
1522                                 }
1523                                 val = rs->iassign [ins->sreg2];
1524                                 if (val >= 0 && val != X86_ECX) {
1525                                         MonoInst *move = create_copy_ins (cfg, X86_ECX, val, NULL);
1526                                         DEBUG (g_print ("\tmoved arg from R%d (%d) to ECX\n", val, ins->sreg2));
1527                                         move->next = ins;
1528                                         g_assert_not_reached ();
1529                                         /* FIXME: where is move connected to the instruction list? */
1530                                         //tmp->prev->data->next = move;
1531                                 }
1532                                 if (need_ecx_spill && !(rs->ifree_mask & (1 << X86_ECX))) {
1533                                         DEBUG (g_print ("\tforced spill of R%d\n", rs->isymbolic [X86_ECX]));
1534                                         get_register_force_spilling (cfg, tmp, ins, rs->isymbolic [X86_ECX]);
1535                                         mono_regstate_free_int (rs, X86_ECX);
1536                                 }
1537                                 /* force-set sreg2 */
1538                                 rs->iassign [ins->sreg2] = X86_ECX;
1539                                 rs->isymbolic [X86_ECX] = ins->sreg2;
1540                                 ins->sreg2 = X86_ECX;
1541                                 rs->ifree_mask &= ~ (1 << X86_ECX);
1542                         }
1543                 } else if (spec [MONO_INST_CLOB] == 'd') { /* division */
1544                         int dest_reg = X86_EAX;
1545                         int clob_reg = X86_EDX;
1546                         if (spec [MONO_INST_DEST] == 'd') {
1547                                 dest_reg = X86_EDX; /* reminder */
1548                                 clob_reg = X86_EAX;
1549                         }
1550                         val = rs->iassign [ins->dreg];
1551                         if (0 && val >= 0 && val != dest_reg && !(rs->ifree_mask & (1 << dest_reg))) {
1552                                 DEBUG (g_print ("\tforced spill of R%d\n", rs->isymbolic [dest_reg]));
1553                                 get_register_force_spilling (cfg, tmp, ins, rs->isymbolic [dest_reg]);
1554                                 mono_regstate_free_int (rs, dest_reg);
1555                         }
1556                         if (val < 0) {
1557                                 if (val < -1) {
1558                                         /* the register gets spilled after this inst */
1559                                         int spill = -val -1;
1560                                         dest_mask = 1 << clob_reg;
1561                                         prev_dreg = ins->dreg;
1562                                         val = mono_regstate_alloc_int (rs, dest_mask);
1563                                         if (val < 0)
1564                                                 val = get_register_spilling (cfg, tmp, ins, dest_mask, ins->dreg);
1565                                         rs->iassign [ins->dreg] = val;
1566                                         if (spill)
1567                                                 create_spilled_store (cfg, spill, val, prev_dreg, ins);
1568                                         DEBUG (g_print ("\tassigned dreg %s to dest R%d\n", mono_arch_regname (val), ins->dreg));
1569                                         rs->isymbolic [val] = prev_dreg;
1570                                         ins->dreg = val;
1571                                         if (val != dest_reg) { /* force a copy */
1572                                                 create_copy_ins (cfg, val, dest_reg, ins);
1573                                         }
1574                                 } else {
1575                                         DEBUG (g_print ("\tshortcut assignment of R%d to %s\n", ins->dreg, mono_arch_regname (dest_reg)));
1576                                         prev_dreg = ins->dreg;
1577                                         rs->iassign [ins->dreg] = dest_reg;
1578                                         rs->isymbolic [dest_reg] = ins->dreg;
1579                                         ins->dreg = dest_reg;
1580                                         rs->ifree_mask &= ~ (1 << dest_reg);
1581                                 }
1582                         } else {
1583                                 //DEBUG (g_print ("dest reg in div assigned: %s\n", mono_arch_regname (val)));
1584                                 if (val != dest_reg) { /* force a copy */
1585                                         create_copy_ins (cfg, val, dest_reg, ins);
1586                                         if (!(rs->ifree_mask & (1 << dest_reg)) && rs->isymbolic [dest_reg] >= MONO_MAX_IREGS) {
1587                                                 DEBUG (g_print ("\tforced spill of R%d\n", rs->isymbolic [dest_reg]));
1588                                                 get_register_force_spilling (cfg, tmp, ins, rs->isymbolic [dest_reg]);
1589                                                 mono_regstate_free_int (rs, dest_reg);
1590                                         }
1591                                 }
1592                         }
1593                         if (!(rs->ifree_mask & (1 << clob_reg)) && (clob_reg != val) && (rs->isymbolic [clob_reg] >= 8)) {
1594                                 DEBUG (g_print ("\tforced spill of clobbered reg R%d\n", rs->isymbolic [clob_reg]));
1595                                 get_register_force_spilling (cfg, tmp, ins, rs->isymbolic [clob_reg]);
1596                                 mono_regstate_free_int (rs, clob_reg);
1597                         }
1598                         src1_mask = 1 << X86_EAX;
1599                         src2_mask = 1 << X86_ECX;
1600                 }
1601                 if (spec [MONO_INST_DEST] == 'l') {
1602                         if (!(rs->ifree_mask & (1 << X86_EAX))) {
1603                                 DEBUG (g_print ("\tforced spill of R%d\n", rs->isymbolic [X86_EAX]));
1604                                 get_register_force_spilling (cfg, tmp, ins, rs->isymbolic [X86_EAX]);
1605                                 mono_regstate_free_int (rs, X86_EAX);
1606                         }
1607                         if (!(rs->ifree_mask & (1 << X86_EDX))) {
1608                                 DEBUG (g_print ("\tforced spill of R%d\n", rs->isymbolic [X86_EDX]));
1609                                 get_register_force_spilling (cfg, tmp, ins, rs->isymbolic [X86_EDX]);
1610                                 mono_regstate_free_int (rs, X86_EDX);
1611                         }
1612                 }
1613
1614                 /* Track dreg */
1615                 if (spec [MONO_INST_DEST] == 'f') {
1616                         if (reginfof [ins->dreg].flags & MONO_X86_FP_NEEDS_SPILL) {
1617                                 GList *spill_node;
1618                                 MonoInst *store;
1619                                 spill_node = g_list_first (fspill_list);
1620                                 g_assert (spill_node);
1621
1622                                 store = create_spilled_store_float (cfg, GPOINTER_TO_INT (spill_node->data), ins->dreg, ins);
1623                                 insert_before_ins (ins, tmp, store);
1624                                 fspill_list = g_list_remove (fspill_list, spill_node->data);
1625                                 fspill--;
1626                         }
1627                 } else if (spec [MONO_INST_DEST] == 'L') {
1628                         int hreg;
1629                         val = rs->iassign [ins->dreg];
1630                         /* check special case when dreg have been moved from ecx (clob shift) */
1631                         if (spec [MONO_INST_CLOB] == 's' && clob_dreg != -1)
1632                                 hreg = clob_dreg + 1;
1633                         else
1634                                 hreg = ins->dreg + 1;
1635
1636                         /* base prev_dreg on fixed hreg, handle clob case */
1637                         prev_dreg = hreg - 1;
1638
1639                         if (val < 0) {
1640                                 int spill = 0;
1641                                 if (val < -1) {
1642                                         /* the register gets spilled after this inst */
1643                                         spill = -val -1;
1644                                 }
1645                                 val = mono_regstate_alloc_int (rs, dest_mask);
1646                                 if (val < 0) /* todo: should we force reg into eax, for opt reasons? */
1647                                         val = get_register_spilling (cfg, tmp, ins, dest_mask, ins->dreg);
1648                                 rs->iassign [ins->dreg] = val;
1649                                 if (spill)
1650                                         create_spilled_store (cfg, spill, val, prev_dreg, ins);
1651                         }
1652
1653                         DEBUG (g_print ("\tassigned dreg (long) %s to dest R%d\n", mono_arch_regname (val), hreg - 1));
1654
1655                         rs->isymbolic [val] = hreg - 1;
1656                         ins->dreg = val;
1657                         
1658                         val = rs->iassign [hreg];
1659                         if (val < 0) {
1660                                 int spill = 0;
1661                                 if (val < -1) {
1662                                         /* the register gets spilled after this inst */
1663                                         spill = -val -1;
1664                                 }
1665                                 val = mono_regstate_alloc_int (rs, dest_mask);
1666                                 if (val < 0) /* todo: should we force reg into edx, for opt reasons? */
1667                                         val = get_register_spilling (cfg, tmp, ins, dest_mask, hreg);
1668                                 rs->iassign [hreg] = val;
1669                                 if (spill)
1670                                         create_spilled_store (cfg, spill, val, hreg, ins);
1671                         }
1672
1673                         DEBUG (g_print ("\tassigned hreg (long) %s to dest R%d\n", mono_arch_regname (val), hreg));
1674                         rs->isymbolic [val] = hreg;
1675                         /* save reg allocating into unused */
1676                         ins->unused = val;
1677
1678                         if (reg_is_freeable (val) && hreg >= 0 && reginfo [hreg].born_in >= i) {
1679                                 DEBUG (g_print ("\tfreeable %s (R%d)\n", mono_arch_regname (val), hreg));
1680                                 mono_regstate_free_int (rs, val);
1681                         }
1682                 }
1683                 else if (ins->dreg >= MONO_MAX_IREGS) {
1684                         val = rs->iassign [ins->dreg];
1685                         prev_dreg = ins->dreg;
1686                         if (val < 0) {
1687                                 int spill = 0;
1688                                 if (val < -1) {
1689                                         /* the register gets spilled after this inst */
1690                                         spill = -val -1;
1691                                 }
1692                                 val = mono_regstate_alloc_int (rs, dest_mask);
1693                                 if (val < 0)
1694                                         val = get_register_spilling (cfg, tmp, ins, dest_mask, ins->dreg);
1695                                 rs->iassign [ins->dreg] = val;
1696                                 if (spill)
1697                                         create_spilled_store (cfg, spill, val, prev_dreg, ins);
1698                         }
1699                         DEBUG (g_print ("\tassigned dreg %s to dest R%d\n", mono_arch_regname (val), ins->dreg));
1700                         rs->isymbolic [val] = prev_dreg;
1701                         ins->dreg = val;
1702                         /* handle cases where lreg needs to be eax:edx */
1703                         if (spec [MONO_INST_DEST] == 'l') {
1704                                 int hreg = prev_dreg + 1;
1705                                 val = rs->iassign [hreg];
1706                                 if (val < 0) {
1707                                         int spill = 0;
1708                                         if (val < -1) {
1709                                                 /* the register gets spilled after this inst */
1710                                                 spill = -val -1;
1711                                         }
1712                                         val = mono_regstate_alloc_int (rs, dest_mask);
1713                                         if (val < 0)
1714                                                 val = get_register_spilling (cfg, tmp, ins, dest_mask, hreg);
1715                                         rs->iassign [hreg] = val;
1716                                         if (spill)
1717                                                 create_spilled_store (cfg, spill, val, hreg, ins);
1718                                 }
1719                                 DEBUG (g_print ("\tassigned hreg %s to dest R%d\n", mono_arch_regname (val), hreg));
1720                                 rs->isymbolic [val] = hreg;
1721                                 if (ins->dreg == X86_EAX) {
1722                                         if (val != X86_EDX)
1723                                                 create_copy_ins (cfg, val, X86_EDX, ins);
1724                                 } else if (ins->dreg == X86_EDX) {
1725                                         if (val == X86_EAX) {
1726                                                 /* swap */
1727                                                 g_assert_not_reached ();
1728                                         } else {
1729                                                 /* two forced copies */
1730                                                 create_copy_ins (cfg, val, X86_EDX, ins);
1731                                                 create_copy_ins (cfg, ins->dreg, X86_EAX, ins);
1732                                         }
1733                                 } else {
1734                                         if (val == X86_EDX) {
1735                                                 create_copy_ins (cfg, ins->dreg, X86_EAX, ins);
1736                                         } else {
1737                                                 /* two forced copies */
1738                                                 create_copy_ins (cfg, val, X86_EDX, ins);
1739                                                 create_copy_ins (cfg, ins->dreg, X86_EAX, ins);
1740                                         }
1741                                 }
1742                                 if (reg_is_freeable (val) && hreg >= 0 && reginfo [hreg].born_in >= i) {
1743                                         DEBUG (g_print ("\tfreeable %s (R%d)\n", mono_arch_regname (val), hreg));
1744                                         mono_regstate_free_int (rs, val);
1745                                 }
1746                         } else if (spec [MONO_INST_DEST] == 'a' && ins->dreg != X86_EAX && spec [MONO_INST_CLOB] != 'd') {
1747                                 /* this instruction only outputs to EAX, need to copy */
1748                                 create_copy_ins (cfg, ins->dreg, X86_EAX, ins);
1749                         } else if (spec [MONO_INST_DEST] == 'd' && ins->dreg != X86_EDX && spec [MONO_INST_CLOB] != 'd') {
1750                                 create_copy_ins (cfg, ins->dreg, X86_EDX, ins);
1751                         }
1752                 }
1753                 if (spec [MONO_INST_DEST] != 'f' && reg_is_freeable (ins->dreg) && prev_dreg >= 0 && reginfo [prev_dreg].born_in >= i) {
1754                         DEBUG (g_print ("\tfreeable %s (R%d) (born in %d)\n", mono_arch_regname (ins->dreg), prev_dreg, reginfo [prev_dreg].born_in));
1755                         mono_regstate_free_int (rs, ins->dreg);
1756                 }
1757                 /* put src1 in EAX if it needs to be */
1758                 if (spec [MONO_INST_SRC1] == 'a') {
1759                         if (!(rs->ifree_mask & (1 << X86_EAX))) {
1760                                 DEBUG (g_print ("\tforced spill of R%d\n", rs->isymbolic [X86_EAX]));
1761                                 get_register_force_spilling (cfg, tmp, ins, rs->isymbolic [X86_EAX]);
1762                                 mono_regstate_free_int (rs, X86_EAX);
1763                         }
1764                         /* force-set sreg1 */
1765                         rs->iassign [ins->sreg1] = X86_EAX;
1766                         rs->isymbolic [X86_EAX] = ins->sreg1;
1767                         ins->sreg1 = X86_EAX;
1768                         rs->ifree_mask &= ~ (1 << X86_EAX);
1769                 }
1770
1771                 /* Track sreg1 */
1772                 if (spec [MONO_INST_SRC1] == 'f') {
1773                         if (reginfof [ins->sreg1].flags & MONO_X86_FP_NEEDS_LOAD) {
1774                                 MonoInst *load;
1775                                 MonoInst *store = NULL;
1776
1777                                 if (reginfof [ins->sreg1].flags & MONO_X86_FP_NEEDS_LOAD_SPILL) {
1778                                         GList *spill_node;
1779                                         spill_node = g_list_first (fspill_list);
1780                                         g_assert (spill_node);
1781
1782                                         store = create_spilled_store_float (cfg, GPOINTER_TO_INT (spill_node->data), ins->sreg1, ins);          
1783                                         fspill_list = g_list_remove (fspill_list, spill_node->data);
1784                                 }
1785
1786                                 fspill++;
1787                                 fspill_list = g_list_prepend (fspill_list, GINT_TO_POINTER(fspill));
1788                                 load = create_spilled_load_float (cfg, fspill, ins->sreg1, ins);
1789                                 insert_before_ins (ins, tmp, load);
1790                                 if (store) 
1791                                         insert_before_ins (load, tmp, store);
1792                         }
1793                 } else if ((spec [MONO_INST_DEST] == 'L') && (spec [MONO_INST_SRC1] == 'L')) {
1794                         /* force source to be same as dest */
1795                         rs->iassign [ins->sreg1] = ins->dreg;
1796                         rs->iassign [ins->sreg1 + 1] = ins->unused;
1797
1798                         DEBUG (g_print ("\tassigned sreg1 (long) %s to sreg1 R%d\n", mono_arch_regname (ins->dreg), ins->sreg1));
1799                         DEBUG (g_print ("\tassigned sreg1 (long-high) %s to sreg1 R%d\n", mono_arch_regname (ins->unused), ins->sreg1 + 1));
1800
1801                         ins->sreg1 = ins->dreg;
1802                         /* no need for this, we know that src1=dest in this cases */
1803                         /*ins->inst_c0 = ins->unused;*/
1804
1805                         /* make sure that we remove them from free mask */
1806                         rs->ifree_mask &= ~ (1 << ins->dreg);
1807                         rs->ifree_mask &= ~ (1 << ins->unused);
1808                 }
1809                 else if (ins->sreg1 >= MONO_MAX_IREGS) {
1810                         val = rs->iassign [ins->sreg1];
1811                         prev_sreg1 = ins->sreg1;
1812                         if (val < 0) {
1813                                 int spill = 0;
1814                                 if (val < -1) {
1815                                         /* the register gets spilled after this inst */
1816                                         spill = -val -1;
1817                                 }
1818                                 if (0 && ins->opcode == OP_MOVE) {
1819                                         /* 
1820                                          * small optimization: the dest register is already allocated
1821                                          * but the src one is not: we can simply assign the same register
1822                                          * here and peephole will get rid of the instruction later.
1823                                          * This optimization may interfere with the clobbering handling:
1824                                          * it removes a mov operation that will be added again to handle clobbering.
1825                                          * There are also some other issues that should with make testjit.
1826                                          */
1827                                         mono_regstate_alloc_int (rs, 1 << ins->dreg);
1828                                         val = rs->iassign [ins->sreg1] = ins->dreg;
1829                                         //g_assert (val >= 0);
1830                                         DEBUG (g_print ("\tfast assigned sreg1 %s to R%d\n", mono_arch_regname (val), ins->sreg1));
1831                                 } else {
1832                                         //g_assert (val == -1); /* source cannot be spilled */
1833                                         val = mono_regstate_alloc_int (rs, src1_mask);
1834                                         if (val < 0)
1835                                                 val = get_register_spilling (cfg, tmp, ins, src1_mask, ins->sreg1);
1836                                         rs->iassign [ins->sreg1] = val;
1837                                         DEBUG (g_print ("\tassigned sreg1 %s to R%d\n", mono_arch_regname (val), ins->sreg1));
1838                                 }
1839                                 if (spill) {
1840                                         MonoInst *store = create_spilled_store (cfg, spill, val, prev_sreg1, NULL);
1841                                         insert_before_ins (ins, tmp, store);
1842                                 }
1843                         }
1844                         rs->isymbolic [val] = prev_sreg1;
1845                         ins->sreg1 = val;
1846                 } else {
1847                         prev_sreg1 = -1;
1848                 }
1849                 /* handle clobbering of sreg1 */
1850                 if ((spec [MONO_INST_CLOB] == '1' || spec [MONO_INST_CLOB] == 's') && ins->dreg != ins->sreg1) {
1851                         MonoInst *copy = create_copy_ins (cfg, ins->dreg, ins->sreg1, NULL);
1852                         DEBUG (g_print ("\tneed to copy sreg1 %s to dreg %s\n", mono_arch_regname (ins->sreg1), mono_arch_regname (ins->dreg)));
1853                         if (ins->sreg2 == -1 || spec [MONO_INST_CLOB] == 's') {
1854                                 /* note: the copy is inserted before the current instruction! */
1855                                 insert_before_ins (ins, tmp, copy);
1856                                 /* we set sreg1 to dest as well */
1857                                 prev_sreg1 = ins->sreg1 = ins->dreg;
1858                         } else {
1859                                 /* inserted after the operation */
1860                                 copy->next = ins->next;
1861                                 ins->next = copy;
1862                         }
1863                 }
1864                 /* track sreg2 */
1865                 if (spec [MONO_INST_SRC2] == 'f') {
1866                         if (reginfof [ins->sreg2].flags & MONO_X86_FP_NEEDS_LOAD) {
1867                                 MonoInst *load;
1868                                 MonoInst *store = NULL;
1869
1870                                 if (reginfof [ins->sreg2].flags & MONO_X86_FP_NEEDS_LOAD_SPILL) {
1871                                         GList *spill_node;
1872
1873                                         spill_node = g_list_first (fspill_list);
1874                                         g_assert (spill_node);
1875                                         if (spec [MONO_INST_SRC1] == 'f' && (reginfof [ins->sreg1].flags & MONO_X86_FP_NEEDS_LOAD_SPILL))
1876                                                 spill_node = g_list_next (spill_node);
1877         
1878                                         store = create_spilled_store_float (cfg, GPOINTER_TO_INT (spill_node->data), ins->sreg2, ins);
1879                                         fspill_list = g_list_remove (fspill_list, spill_node->data);
1880                                 } 
1881                                 
1882                                 fspill++;
1883                                 fspill_list = g_list_prepend (fspill_list, GINT_TO_POINTER(fspill));
1884                                 load = create_spilled_load_float (cfg, fspill, ins->sreg2, ins);
1885                                 insert_before_ins (ins, tmp, load);
1886                                 if (store) 
1887                                         insert_before_ins (load, tmp, store);
1888                         }
1889                 } 
1890                 else if (ins->sreg2 >= MONO_MAX_IREGS) {
1891                         val = rs->iassign [ins->sreg2];
1892                         prev_sreg2 = ins->sreg2;
1893                         if (val < 0) {
1894                                 int spill = 0;
1895                                 if (val < -1) {
1896                                         /* the register gets spilled after this inst */
1897                                         spill = -val -1;
1898                                 }
1899                                 val = mono_regstate_alloc_int (rs, src2_mask);
1900                                 if (val < 0)
1901                                         val = get_register_spilling (cfg, tmp, ins, src2_mask, ins->sreg2);
1902                                 rs->iassign [ins->sreg2] = val;
1903                                 DEBUG (g_print ("\tassigned sreg2 %s to R%d\n", mono_arch_regname (val), ins->sreg2));
1904                                 if (spill)
1905                                         create_spilled_store (cfg, spill, val, prev_sreg2, ins);
1906                         }
1907                         rs->isymbolic [val] = prev_sreg2;
1908                         ins->sreg2 = val;
1909                         if (spec [MONO_INST_CLOB] == 's' && ins->sreg2 != X86_ECX) {
1910                                 DEBUG (g_print ("\tassigned sreg2 %s to R%d, but ECX is needed (R%d)\n", mono_arch_regname (val), ins->sreg2, rs->iassign [X86_ECX]));
1911                         }
1912                 } else {
1913                         prev_sreg2 = -1;
1914                 }
1915
1916                 if (spec [MONO_INST_CLOB] == 'c') {
1917                         int j, s;
1918                         guint32 clob_mask = X86_CALLEE_REGS;
1919                         for (j = 0; j < MONO_MAX_IREGS; ++j) {
1920                                 s = 1 << j;
1921                                 if ((clob_mask & s) && !(rs->ifree_mask & s) && j != ins->sreg1) {
1922                                         //g_warning ("register %s busy at call site\n", mono_arch_regname (j));
1923                                 }
1924                         }
1925                 }
1926                 /*if (reg_is_freeable (ins->sreg1) && prev_sreg1 >= 0 && reginfo [prev_sreg1].born_in >= i) {
1927                         DEBUG (g_print ("freeable %s\n", mono_arch_regname (ins->sreg1)));
1928                         mono_regstate_free_int (rs, ins->sreg1);
1929                 }
1930                 if (reg_is_freeable (ins->sreg2) && prev_sreg2 >= 0 && reginfo [prev_sreg2].born_in >= i) {
1931                         DEBUG (g_print ("freeable %s\n", mono_arch_regname (ins->sreg2)));
1932                         mono_regstate_free_int (rs, ins->sreg2);
1933                 }*/
1934         
1935                 //DEBUG (print_ins (i, ins));
1936                 /* this may result from a insert_before call */
1937                 if (!tmp->next)
1938                         bb->code = tmp->data;
1939                 tmp = tmp->next;
1940         }
1941
1942         g_free (reginfo);
1943         g_free (reginfof);
1944         g_list_free (fspill_list);
1945 }
1946
1947 static unsigned char*
1948 emit_float_to_int (MonoCompile *cfg, guchar *code, int dreg, int size, gboolean is_signed)
1949 {
1950         x86_alu_reg_imm (code, X86_SUB, X86_ESP, 4);
1951         x86_fnstcw_membase(code, X86_ESP, 0);
1952         x86_mov_reg_membase (code, dreg, X86_ESP, 0, 2);
1953         x86_alu_reg_imm (code, X86_OR, dreg, 0xc00);
1954         x86_mov_membase_reg (code, X86_ESP, 2, dreg, 2);
1955         x86_fldcw_membase (code, X86_ESP, 2);
1956         if (size == 8) {
1957                 x86_alu_reg_imm (code, X86_SUB, X86_ESP, 8);
1958                 x86_fist_pop_membase (code, X86_ESP, 0, TRUE);
1959                 x86_pop_reg (code, dreg);
1960                 /* FIXME: need the high register 
1961                  * x86_pop_reg (code, dreg_high);
1962                  */
1963         } else {
1964                 x86_push_reg (code, X86_EAX); // SP = SP - 4
1965                 x86_fist_pop_membase (code, X86_ESP, 0, FALSE);
1966                 x86_pop_reg (code, dreg);
1967         }
1968         x86_fldcw_membase (code, X86_ESP, 0);
1969         x86_alu_reg_imm (code, X86_ADD, X86_ESP, 4);
1970
1971         if (size == 1)
1972                 x86_widen_reg (code, dreg, dreg, is_signed, FALSE);
1973         else if (size == 2)
1974                 x86_widen_reg (code, dreg, dreg, is_signed, TRUE);
1975         return code;
1976 }
1977
1978 static unsigned char*
1979 mono_emit_stack_alloc (guchar *code, MonoInst* tree)
1980 {
1981         int sreg = tree->sreg1;
1982 #ifdef PLATFORM_WIN32
1983         guint8* br[5];
1984
1985         /*
1986          * Under Windows:
1987          * If requested stack size is larger than one page,
1988          * perform stack-touch operation
1989          */
1990         /*
1991          * Generate stack probe code.
1992          * Under Windows, it is necessary to allocate one page at a time,
1993          * "touching" stack after each successful sub-allocation. This is
1994          * because of the way stack growth is implemented - there is a
1995          * guard page before the lowest stack page that is currently commited.
1996          * Stack normally grows sequentially so OS traps access to the
1997          * guard page and commits more pages when needed.
1998          */
1999         x86_test_reg_imm (code, sreg, ~0xFFF);
2000         br[0] = code; x86_branch8 (code, X86_CC_Z, 0, FALSE);
2001
2002         br[2] = code; /* loop */
2003         x86_alu_reg_imm (code, X86_SUB, X86_ESP, 0x1000);
2004         x86_test_membase_reg (code, X86_ESP, 0, X86_ESP);
2005         x86_alu_reg_imm (code, X86_SUB, sreg, 0x1000);
2006         x86_alu_reg_imm (code, X86_CMP, sreg, 0x1000);
2007         br[3] = code; x86_branch8 (code, X86_CC_AE, 0, FALSE);
2008         x86_patch (br[3], br[2]);
2009         x86_test_reg_reg (code, sreg, sreg);
2010         br[4] = code; x86_branch8 (code, X86_CC_Z, 0, FALSE);
2011         x86_alu_reg_reg (code, X86_SUB, X86_ESP, sreg);
2012
2013         br[1] = code; x86_jump8 (code, 0);
2014
2015         x86_patch (br[0], code);
2016         x86_alu_reg_reg (code, X86_SUB, X86_ESP, sreg);
2017         x86_patch (br[1], code);
2018         x86_patch (br[4], code);
2019 #else /* PLATFORM_WIN32 */
2020         x86_alu_reg_reg (code, X86_SUB, X86_ESP, tree->sreg1);
2021 #endif
2022         if (tree->flags & MONO_INST_INIT) {
2023                 int offset = 0;
2024                 if (tree->dreg != X86_EAX && sreg != X86_EAX) {
2025                         x86_push_reg (code, X86_EAX);
2026                         offset += 4;
2027                 }
2028                 if (tree->dreg != X86_ECX && sreg != X86_ECX) {
2029                         x86_push_reg (code, X86_ECX);
2030                         offset += 4;
2031                 }
2032                 if (tree->dreg != X86_EDI && sreg != X86_EDI) {
2033                         x86_push_reg (code, X86_EDI);
2034                         offset += 4;
2035                 }
2036                 
2037                 x86_shift_reg_imm (code, X86_SHR, sreg, 2);
2038                 if (sreg != X86_ECX)
2039                         x86_mov_reg_reg (code, X86_ECX, sreg, 4);
2040                 x86_alu_reg_reg (code, X86_XOR, X86_EAX, X86_EAX);
2041                                 
2042                 x86_lea_membase (code, X86_EDI, X86_ESP, offset);
2043                 x86_cld (code);
2044                 x86_prefix (code, X86_REP_PREFIX);
2045                 x86_stosl (code);
2046                 
2047                 if (tree->dreg != X86_EDI && sreg != X86_EDI)
2048                         x86_pop_reg (code, X86_EDI);
2049                 if (tree->dreg != X86_ECX && sreg != X86_ECX)
2050                         x86_pop_reg (code, X86_ECX);
2051                 if (tree->dreg != X86_EAX && sreg != X86_EAX)
2052                         x86_pop_reg (code, X86_EAX);
2053         }
2054         return code;
2055 }
2056
2057 #define REAL_PRINT_REG(text,reg) \
2058 mono_assert (reg >= 0); \
2059 x86_push_reg (code, X86_EAX); \
2060 x86_push_reg (code, X86_EDX); \
2061 x86_push_reg (code, X86_ECX); \
2062 x86_push_reg (code, reg); \
2063 x86_push_imm (code, reg); \
2064 x86_push_imm (code, text " %d %p\n"); \
2065 x86_mov_reg_imm (code, X86_EAX, printf); \
2066 x86_call_reg (code, X86_EAX); \
2067 x86_alu_reg_imm (code, X86_ADD, X86_ESP, 3*4); \
2068 x86_pop_reg (code, X86_ECX); \
2069 x86_pop_reg (code, X86_EDX); \
2070 x86_pop_reg (code, X86_EAX);
2071
2072 void
2073 mono_arch_output_basic_block (MonoCompile *cfg, MonoBasicBlock *bb)
2074 {
2075         MonoInst *ins;
2076         MonoCallInst *call;
2077         guint offset;
2078         guint8 *code = cfg->native_code + cfg->code_len;
2079         MonoInst *last_ins = NULL;
2080         guint last_offset = 0;
2081         int max_len, cpos;
2082
2083         if (cfg->opt & MONO_OPT_PEEPHOLE)
2084                 peephole_pass (cfg, bb);
2085
2086         if (cfg->opt & MONO_OPT_LOOP) {
2087                 int pad, align = 8;
2088                 /* set alignment depending on cpu */
2089                 if (bb->nesting && (bb->in_count == 1) && (pad = (cfg->code_len & (align - 1)))) {
2090                         pad = align - pad;
2091                         /*g_print ("adding %d pad at %x to loop in %s\n", pad, cfg->code_len, cfg->method->name);*/
2092                         x86_padding (code, pad);
2093                         cfg->code_len += pad;
2094                         bb->native_offset = cfg->code_len;
2095                 }
2096         }
2097
2098         if (cfg->verbose_level > 2)
2099                 g_print ("Basic block %d starting at offset 0x%x\n", bb->block_num, bb->native_offset);
2100
2101         cpos = bb->max_offset;
2102
2103         if (cfg->prof_options & MONO_PROFILE_COVERAGE) {
2104                 MonoProfileCoverageInfo *cov = cfg->coverage_info;
2105                 g_assert (!mono_compile_aot);
2106                 cpos += 6;
2107
2108                 cov->data [bb->dfn].cil_code = bb->cil_code;
2109                 /* this is not thread save, but good enough */
2110                 x86_inc_mem (code, &cov->data [bb->dfn].count); 
2111         }
2112
2113         offset = code - cfg->native_code;
2114
2115         ins = bb->code;
2116         while (ins) {
2117                 offset = code - cfg->native_code;
2118
2119                 max_len = ((guint8 *)ins_spec [ins->opcode])[MONO_INST_LEN];
2120
2121                 if (offset > (cfg->code_size - max_len - 16)) {
2122                         cfg->code_size *= 2;
2123                         cfg->native_code = g_realloc (cfg->native_code, cfg->code_size);
2124                         code = cfg->native_code + offset;
2125                         mono_jit_stats.code_reallocs++;
2126                 }
2127
2128                 mono_debug_record_line_number (cfg, ins, offset);
2129
2130                 switch (ins->opcode) {
2131                 case OP_BIGMUL:
2132                         x86_mul_reg (code, ins->sreg2, TRUE);
2133                         break;
2134                 case OP_BIGMUL_UN:
2135                         x86_mul_reg (code, ins->sreg2, FALSE);
2136                         break;
2137                 case OP_X86_SETEQ_MEMBASE:
2138                         x86_set_membase (code, X86_CC_EQ, ins->inst_basereg, ins->inst_offset, TRUE);
2139                         break;
2140                 case OP_STOREI1_MEMBASE_IMM:
2141                         x86_mov_membase_imm (code, ins->inst_destbasereg, ins->inst_offset, ins->inst_imm, 1);
2142                         break;
2143                 case OP_STOREI2_MEMBASE_IMM:
2144                         x86_mov_membase_imm (code, ins->inst_destbasereg, ins->inst_offset, ins->inst_imm, 2);
2145                         break;
2146                 case OP_STORE_MEMBASE_IMM:
2147                 case OP_STOREI4_MEMBASE_IMM:
2148                         x86_mov_membase_imm (code, ins->inst_destbasereg, ins->inst_offset, ins->inst_imm, 4);
2149                         break;
2150                 case OP_STOREI1_MEMBASE_REG:
2151                         x86_mov_membase_reg (code, ins->inst_destbasereg, ins->inst_offset, ins->sreg1, 1);
2152                         break;
2153                 case OP_STOREI2_MEMBASE_REG:
2154                         x86_mov_membase_reg (code, ins->inst_destbasereg, ins->inst_offset, ins->sreg1, 2);
2155                         break;
2156                 case OP_STORE_MEMBASE_REG:
2157                 case OP_STOREI4_MEMBASE_REG:
2158                         x86_mov_membase_reg (code, ins->inst_destbasereg, ins->inst_offset, ins->sreg1, 4);
2159                         break;
2160                 case CEE_LDIND_I:
2161                 case CEE_LDIND_I4:
2162                 case CEE_LDIND_U4:
2163                         x86_mov_reg_mem (code, ins->dreg, ins->inst_p0, 4);
2164                         break;
2165                 case OP_LOADU4_MEM:
2166                         x86_mov_reg_imm (code, ins->dreg, ins->inst_p0);
2167                         x86_mov_reg_membase (code, ins->dreg, ins->dreg, 0, 4);
2168                         break;
2169                 case OP_LOAD_MEMBASE:
2170                 case OP_LOADI4_MEMBASE:
2171                 case OP_LOADU4_MEMBASE:
2172                         x86_mov_reg_membase (code, ins->dreg, ins->inst_basereg, ins->inst_offset, 4);
2173                         break;
2174                 case OP_LOADU1_MEMBASE:
2175                         x86_widen_membase (code, ins->dreg, ins->inst_basereg, ins->inst_offset, FALSE, FALSE);
2176                         break;
2177                 case OP_LOADI1_MEMBASE:
2178                         x86_widen_membase (code, ins->dreg, ins->inst_basereg, ins->inst_offset, TRUE, FALSE);
2179                         break;
2180                 case OP_LOADU2_MEMBASE:
2181                         x86_widen_membase (code, ins->dreg, ins->inst_basereg, ins->inst_offset, FALSE, TRUE);
2182                         break;
2183                 case OP_LOADI2_MEMBASE:
2184                         x86_widen_membase (code, ins->dreg, ins->inst_basereg, ins->inst_offset, TRUE, TRUE);
2185                         break;
2186                 case CEE_CONV_I1:
2187                         x86_widen_reg (code, ins->dreg, ins->sreg1, TRUE, FALSE);
2188                         break;
2189                 case CEE_CONV_I2:
2190                         x86_widen_reg (code, ins->dreg, ins->sreg1, TRUE, TRUE);
2191                         break;
2192                 case CEE_CONV_U1:
2193                         x86_widen_reg (code, ins->dreg, ins->sreg1, FALSE, FALSE);
2194                         break;
2195                 case CEE_CONV_U2:
2196                         x86_widen_reg (code, ins->dreg, ins->sreg1, FALSE, TRUE);
2197                         break;
2198                 case OP_COMPARE:
2199                         x86_alu_reg_reg (code, X86_CMP, ins->sreg1, ins->sreg2);
2200                         break;
2201                 case OP_COMPARE_IMM:
2202                         x86_alu_reg_imm (code, X86_CMP, ins->sreg1, ins->inst_imm);
2203                         break;
2204                 case OP_X86_COMPARE_MEMBASE_REG:
2205                         x86_alu_membase_reg (code, X86_CMP, ins->inst_basereg, ins->inst_offset, ins->sreg2);
2206                         break;
2207                 case OP_X86_COMPARE_MEMBASE_IMM:
2208                         x86_alu_membase_imm (code, X86_CMP, ins->inst_basereg, ins->inst_offset, ins->inst_imm);
2209                         break;
2210                 case OP_X86_COMPARE_REG_MEMBASE:
2211                         x86_alu_reg_membase (code, X86_CMP, ins->sreg1, ins->sreg2, ins->inst_offset);
2212                         break;
2213                 case OP_X86_TEST_NULL:
2214                         x86_test_reg_reg (code, ins->sreg1, ins->sreg1);
2215                         break;
2216                 case OP_X86_ADD_MEMBASE_IMM:
2217                         x86_alu_membase_imm (code, X86_ADD, ins->inst_basereg, ins->inst_offset, ins->inst_imm);
2218                         break;
2219                 case OP_X86_ADD_MEMBASE:
2220                         x86_alu_reg_membase (code, X86_ADD, ins->sreg1, ins->sreg2, ins->inst_offset);
2221                         break;
2222                 case OP_X86_SUB_MEMBASE_IMM:
2223                         x86_alu_membase_imm (code, X86_SUB, ins->inst_basereg, ins->inst_offset, ins->inst_imm);
2224                         break;
2225                 case OP_X86_SUB_MEMBASE:
2226                         x86_alu_reg_membase (code, X86_SUB, ins->sreg1, ins->sreg2, ins->inst_offset);
2227                         break;
2228                 case OP_X86_INC_MEMBASE:
2229                         x86_inc_membase (code, ins->inst_basereg, ins->inst_offset);
2230                         break;
2231                 case OP_X86_INC_REG:
2232                         x86_inc_reg (code, ins->dreg);
2233                         break;
2234                 case OP_X86_DEC_MEMBASE:
2235                         x86_dec_membase (code, ins->inst_basereg, ins->inst_offset);
2236                         break;
2237                 case OP_X86_DEC_REG:
2238                         x86_dec_reg (code, ins->dreg);
2239                         break;
2240                 case OP_X86_MUL_MEMBASE:
2241                         x86_imul_reg_membase (code, ins->sreg1, ins->sreg2, ins->inst_offset);
2242                         break;
2243                 case CEE_BREAK:
2244                         x86_breakpoint (code);
2245                         break;
2246                 case OP_ADDCC:
2247                 case CEE_ADD:
2248                         x86_alu_reg_reg (code, X86_ADD, ins->sreg1, ins->sreg2);
2249                         break;
2250                 case OP_ADC:
2251                         x86_alu_reg_reg (code, X86_ADC, ins->sreg1, ins->sreg2);
2252                         break;
2253                 case OP_ADD_IMM:
2254                         x86_alu_reg_imm (code, X86_ADD, ins->dreg, ins->inst_imm);
2255                         break;
2256                 case OP_ADC_IMM:
2257                         x86_alu_reg_imm (code, X86_ADC, ins->dreg, ins->inst_imm);
2258                         break;
2259                 case OP_SUBCC:
2260                 case CEE_SUB:
2261                         x86_alu_reg_reg (code, X86_SUB, ins->sreg1, ins->sreg2);
2262                         break;
2263                 case OP_SBB:
2264                         x86_alu_reg_reg (code, X86_SBB, ins->sreg1, ins->sreg2);
2265                         break;
2266                 case OP_SUB_IMM:
2267                         x86_alu_reg_imm (code, X86_SUB, ins->dreg, ins->inst_imm);
2268                         break;
2269                 case OP_SBB_IMM:
2270                         x86_alu_reg_imm (code, X86_SBB, ins->dreg, ins->inst_imm);
2271                         break;
2272                 case CEE_AND:
2273                         x86_alu_reg_reg (code, X86_AND, ins->sreg1, ins->sreg2);
2274                         break;
2275                 case OP_AND_IMM:
2276                         x86_alu_reg_imm (code, X86_AND, ins->sreg1, ins->inst_imm);
2277                         break;
2278                 case CEE_DIV:
2279                         x86_cdq (code);
2280                         x86_div_reg (code, ins->sreg2, TRUE);
2281                         break;
2282                 case CEE_DIV_UN:
2283                         x86_alu_reg_reg (code, X86_XOR, X86_EDX, X86_EDX);
2284                         x86_div_reg (code, ins->sreg2, FALSE);
2285                         break;
2286                 case OP_DIV_IMM:
2287                         x86_mov_reg_imm (code, ins->sreg2, ins->inst_imm);
2288                         x86_cdq (code);
2289                         x86_div_reg (code, ins->sreg2, TRUE);
2290                         break;
2291                 case CEE_REM:
2292                         x86_cdq (code);
2293                         x86_div_reg (code, ins->sreg2, TRUE);
2294                         break;
2295                 case CEE_REM_UN:
2296                         x86_alu_reg_reg (code, X86_XOR, X86_EDX, X86_EDX);
2297                         x86_div_reg (code, ins->sreg2, FALSE);
2298                         break;
2299                 case OP_REM_IMM:
2300                         x86_mov_reg_imm (code, ins->sreg2, ins->inst_imm);
2301                         x86_cdq (code);
2302                         x86_div_reg (code, ins->sreg2, TRUE);
2303                         break;
2304                 case CEE_OR:
2305                         x86_alu_reg_reg (code, X86_OR, ins->sreg1, ins->sreg2);
2306                         break;
2307                 case OP_OR_IMM:
2308                         x86_alu_reg_imm (code, X86_OR, ins->sreg1, ins->inst_imm);
2309                         break;
2310                 case CEE_XOR:
2311                         x86_alu_reg_reg (code, X86_XOR, ins->sreg1, ins->sreg2);
2312                         break;
2313                 case OP_XOR_IMM:
2314                         x86_alu_reg_imm (code, X86_XOR, ins->sreg1, ins->inst_imm);
2315                         break;
2316                 case CEE_SHL:
2317                         g_assert (ins->sreg2 == X86_ECX);
2318                         x86_shift_reg (code, X86_SHL, ins->dreg);
2319                         break;
2320                 case CEE_SHR:
2321                         g_assert (ins->sreg2 == X86_ECX);
2322                         x86_shift_reg (code, X86_SAR, ins->dreg);
2323                         break;
2324                 case OP_SHR_IMM:
2325                         x86_shift_reg_imm (code, X86_SAR, ins->dreg, ins->inst_imm);
2326                         break;
2327                 case OP_SHR_UN_IMM:
2328                         x86_shift_reg_imm (code, X86_SHR, ins->dreg, ins->inst_imm);
2329                         break;
2330                 case CEE_SHR_UN:
2331                         g_assert (ins->sreg2 == X86_ECX);
2332                         x86_shift_reg (code, X86_SHR, ins->dreg);
2333                         break;
2334                 case OP_SHL_IMM:
2335                         x86_shift_reg_imm (code, X86_SHL, ins->dreg, ins->inst_imm);
2336                         break;
2337                 case OP_LSHL: {
2338                         guint8 *jump_to_end;
2339
2340                         /* handle shifts below 32 bits */
2341                         x86_shld_reg (code, ins->unused, ins->sreg1);
2342                         x86_shift_reg (code, X86_SHL, ins->sreg1);
2343
2344                         x86_test_reg_imm (code, X86_ECX, 32);
2345                         jump_to_end = code; x86_branch8 (code, X86_CC_EQ, 0, TRUE);
2346
2347                         /* handle shift over 32 bit */
2348                         x86_mov_reg_reg (code, ins->unused, ins->sreg1, 4);
2349                         x86_clear_reg (code, ins->sreg1);
2350                         
2351                         x86_patch (jump_to_end, code);
2352                         }
2353                         break;
2354                 case OP_LSHR: {
2355                         guint8 *jump_to_end;
2356
2357                         /* handle shifts below 32 bits */
2358                         x86_shrd_reg (code, ins->sreg1, ins->unused);
2359                         x86_shift_reg (code, X86_SAR, ins->unused);
2360
2361                         x86_test_reg_imm (code, X86_ECX, 32);
2362                         jump_to_end = code; x86_branch8 (code, X86_CC_EQ, 0, FALSE);
2363
2364                         /* handle shifts over 31 bits */
2365                         x86_mov_reg_reg (code, ins->sreg1, ins->unused, 4);
2366                         x86_shift_reg_imm (code, X86_SAR, ins->unused, 31);
2367                         
2368                         x86_patch (jump_to_end, code);
2369                         }
2370                         break;
2371                 case OP_LSHR_UN: {
2372                         guint8 *jump_to_end;
2373
2374                         /* handle shifts below 32 bits */
2375                         x86_shrd_reg (code, ins->sreg1, ins->unused);
2376                         x86_shift_reg (code, X86_SHR, ins->unused);
2377
2378                         x86_test_reg_imm (code, X86_ECX, 32);
2379                         jump_to_end = code; x86_branch8 (code, X86_CC_EQ, 0, FALSE);
2380
2381                         /* handle shifts over 31 bits */
2382                         x86_mov_reg_reg (code, ins->sreg1, ins->unused, 4);
2383                         x86_shift_reg_imm (code, X86_SHR, ins->unused, 31);
2384                         
2385                         x86_patch (jump_to_end, code);
2386                         }
2387                         break;
2388                 case OP_LSHL_IMM:
2389                         if (ins->inst_imm >= 32) {
2390                                 x86_mov_reg_reg (code, ins->unused, ins->sreg1, 4);
2391                                 x86_clear_reg (code, ins->sreg1);
2392                                 x86_shift_reg_imm (code, X86_SHL, ins->unused, ins->inst_imm - 32);
2393                         } else {
2394                                 x86_shld_reg_imm (code, ins->unused, ins->sreg1, ins->inst_imm);
2395                                 x86_shift_reg_imm (code, X86_SHL, ins->sreg1, ins->inst_imm);
2396                         }
2397                         break;
2398                 case OP_LSHR_IMM:
2399                         if (ins->inst_imm >= 32) {
2400                                 x86_mov_reg_reg (code, ins->sreg1, ins->unused,  4);
2401                                 x86_shift_reg_imm (code, X86_SAR, ins->unused, 0x1f);
2402                                 x86_shift_reg_imm (code, X86_SAR, ins->sreg1, ins->inst_imm - 32);
2403                         } else {
2404                                 x86_shrd_reg_imm (code, ins->sreg1, ins->unused, ins->inst_imm);
2405                                 x86_shift_reg_imm (code, X86_SAR, ins->unused, ins->inst_imm);
2406                         }
2407                         break;
2408                 case OP_LSHR_UN_IMM:
2409                         if (ins->inst_imm >= 32) {
2410                                 x86_mov_reg_reg (code, ins->sreg1, ins->unused, 4);
2411                                 x86_clear_reg (code, ins->unused);
2412                                 x86_shift_reg_imm (code, X86_SHR, ins->sreg1, ins->inst_imm - 32);
2413                         } else {
2414                                 x86_shrd_reg_imm (code, ins->sreg1, ins->unused, ins->inst_imm);
2415                                 x86_shift_reg_imm (code, X86_SHR, ins->unused, ins->inst_imm);
2416                         }
2417                         break;
2418                 case CEE_NOT:
2419                         x86_not_reg (code, ins->sreg1);
2420                         break;
2421                 case CEE_NEG:
2422                         x86_neg_reg (code, ins->sreg1);
2423                         break;
2424                 case OP_SEXT_I1:
2425                         x86_widen_reg (code, ins->dreg, ins->sreg1, TRUE, FALSE);
2426                         break;
2427                 case OP_SEXT_I2:
2428                         x86_widen_reg (code, ins->dreg, ins->sreg1, TRUE, TRUE);
2429                         break;
2430                 case CEE_MUL:
2431                         x86_imul_reg_reg (code, ins->sreg1, ins->sreg2);
2432                         break;
2433                 case OP_MUL_IMM:
2434                         x86_imul_reg_reg_imm (code, ins->dreg, ins->sreg1, ins->inst_imm);
2435                         break;
2436                 case CEE_MUL_OVF:
2437                         x86_imul_reg_reg (code, ins->sreg1, ins->sreg2);
2438                         EMIT_COND_SYSTEM_EXCEPTION (X86_CC_O, FALSE, "OverflowException");
2439                         break;
2440                 case CEE_MUL_OVF_UN: {
2441                         /* the mul operation and the exception check should most likely be split */
2442                         int non_eax_reg, saved_eax = FALSE, saved_edx = FALSE;
2443                         /*g_assert (ins->sreg2 == X86_EAX);
2444                         g_assert (ins->dreg == X86_EAX);*/
2445                         if (ins->sreg2 == X86_EAX) {
2446                                 non_eax_reg = ins->sreg1;
2447                         } else if (ins->sreg1 == X86_EAX) {
2448                                 non_eax_reg = ins->sreg2;
2449                         } else {
2450                                 /* no need to save since we're going to store to it anyway */
2451                                 if (ins->dreg != X86_EAX) {
2452                                         saved_eax = TRUE;
2453                                         x86_push_reg (code, X86_EAX);
2454                                 }
2455                                 x86_mov_reg_reg (code, X86_EAX, ins->sreg1, 4);
2456                                 non_eax_reg = ins->sreg2;
2457                         }
2458                         if (ins->dreg == X86_EDX) {
2459                                 if (!saved_eax) {
2460                                         saved_eax = TRUE;
2461                                         x86_push_reg (code, X86_EAX);
2462                                 }
2463                         } else if (ins->dreg != X86_EAX) {
2464                                 saved_edx = TRUE;
2465                                 x86_push_reg (code, X86_EDX);
2466                         }
2467                         x86_mul_reg (code, non_eax_reg, FALSE);
2468                         /* save before the check since pop and mov don't change the flags */
2469                         if (ins->dreg != X86_EAX)
2470                                 x86_mov_reg_reg (code, ins->dreg, X86_EAX, 4);
2471                         if (saved_edx)
2472                                 x86_pop_reg (code, X86_EDX);
2473                         if (saved_eax)
2474                                 x86_pop_reg (code, X86_EAX);
2475                         EMIT_COND_SYSTEM_EXCEPTION (X86_CC_O, FALSE, "OverflowException");
2476                         break;
2477                 }
2478                 case OP_ICONST:
2479                         x86_mov_reg_imm (code, ins->dreg, ins->inst_c0);
2480                         break;
2481                 case OP_AOTCONST:
2482                         mono_add_patch_info (cfg, offset, (MonoJumpInfoType)ins->inst_i1, ins->inst_p0);
2483                         x86_mov_reg_imm (code, ins->dreg, 0);
2484                         break;
2485                 case CEE_CONV_I4:
2486                 case OP_MOVE:
2487                         x86_mov_reg_reg (code, ins->dreg, ins->sreg1, 4);
2488                         break;
2489                 case CEE_CONV_U4:
2490                         g_assert_not_reached ();
2491                 case CEE_JMP: {
2492                         /*
2493                          * Note: this 'frame destruction' logic is useful for tail calls, too.
2494                          * Keep in sync with the code in emit_epilog.
2495                          */
2496                         int pos = 0;
2497
2498                         /* FIXME: no tracing support... */
2499                         if (cfg->prof_options & MONO_PROFILE_ENTER_LEAVE)
2500                                 code = mono_arch_instrument_epilog (cfg, mono_profiler_method_leave, code, FALSE);
2501                         /* reset offset to make max_len work */
2502                         offset = code - cfg->native_code;
2503
2504                         g_assert (!cfg->method->save_lmf);
2505
2506                         if (cfg->used_int_regs & (1 << X86_EBX))
2507                                 pos -= 4;
2508                         if (cfg->used_int_regs & (1 << X86_EDI))
2509                                 pos -= 4;
2510                         if (cfg->used_int_regs & (1 << X86_ESI))
2511                                 pos -= 4;
2512                         if (pos)
2513                                 x86_lea_membase (code, X86_ESP, X86_EBP, pos);
2514         
2515                         if (cfg->used_int_regs & (1 << X86_ESI))
2516                                 x86_pop_reg (code, X86_ESI);
2517                         if (cfg->used_int_regs & (1 << X86_EDI))
2518                                 x86_pop_reg (code, X86_EDI);
2519                         if (cfg->used_int_regs & (1 << X86_EBX))
2520                                 x86_pop_reg (code, X86_EBX);
2521         
2522                         /* restore ESP/EBP */
2523                         x86_leave (code);
2524                         offset = code - cfg->native_code;
2525                         mono_add_patch_info (cfg, offset, MONO_PATCH_INFO_METHOD_JUMP, ins->inst_p0);
2526                         x86_jump32 (code, 0);
2527                         break;
2528                 }
2529                 case OP_CHECK_THIS:
2530                         /* ensure ins->sreg1 is not NULL */
2531                         x86_alu_membase_imm (code, X86_CMP, ins->sreg1, 0, 0);
2532                         break;
2533                 case OP_ARGLIST: {
2534                         int hreg = ins->sreg1 == X86_EAX? X86_ECX: X86_EAX;
2535                         x86_push_reg (code, hreg);
2536                         x86_lea_membase (code, hreg, X86_EBP, cfg->sig_cookie);
2537                         x86_mov_membase_reg (code, ins->sreg1, 0, hreg, 4);
2538                         x86_pop_reg (code, hreg);
2539                         break;
2540                 }
2541                 case OP_FCALL:
2542                 case OP_LCALL:
2543                 case OP_VCALL:
2544                 case OP_VOIDCALL:
2545                 case CEE_CALL:
2546                         call = (MonoCallInst*)ins;
2547                         if (ins->flags & MONO_INST_HAS_METHOD)
2548                                 mono_add_patch_info (cfg, offset, MONO_PATCH_INFO_METHOD, call->method);
2549                         else {
2550                                 mono_add_patch_info (cfg, offset, MONO_PATCH_INFO_ABS, call->fptr);
2551                         }
2552                         x86_call_code (code, 0);
2553                         if (call->stack_usage && !CALLCONV_IS_STDCALL (call->signature->call_convention))
2554                                 x86_alu_reg_imm (code, X86_ADD, X86_ESP, call->stack_usage);
2555                         break;
2556                 case OP_FCALL_REG:
2557                 case OP_LCALL_REG:
2558                 case OP_VCALL_REG:
2559                 case OP_VOIDCALL_REG:
2560                 case OP_CALL_REG:
2561                         call = (MonoCallInst*)ins;
2562                         x86_call_reg (code, ins->sreg1);
2563                         if (call->stack_usage && !CALLCONV_IS_STDCALL (call->signature->call_convention))
2564                                 x86_alu_reg_imm (code, X86_ADD, X86_ESP, call->stack_usage);
2565                         break;
2566                 case OP_FCALL_MEMBASE:
2567                 case OP_LCALL_MEMBASE:
2568                 case OP_VCALL_MEMBASE:
2569                 case OP_VOIDCALL_MEMBASE:
2570                 case OP_CALL_MEMBASE:
2571                         call = (MonoCallInst*)ins;
2572                         x86_call_membase (code, ins->sreg1, ins->inst_offset);
2573                         if (call->stack_usage && !CALLCONV_IS_STDCALL (call->signature->call_convention))
2574                                 x86_alu_reg_imm (code, X86_ADD, X86_ESP, call->stack_usage);
2575                         break;
2576                 case OP_OUTARG:
2577                 case OP_X86_PUSH:
2578                         x86_push_reg (code, ins->sreg1);
2579                         break;
2580                 case OP_X86_PUSH_IMM:
2581                         x86_push_imm (code, ins->inst_imm);
2582                         break;
2583                 case OP_X86_PUSH_MEMBASE:
2584                         x86_push_membase (code, ins->inst_basereg, ins->inst_offset);
2585                         break;
2586                 case OP_X86_PUSH_OBJ: 
2587                         x86_alu_reg_imm (code, X86_SUB, X86_ESP, ins->inst_imm);
2588                         x86_push_reg (code, X86_EDI);
2589                         x86_push_reg (code, X86_ESI);
2590                         x86_push_reg (code, X86_ECX);
2591                         if (ins->inst_offset)
2592                                 x86_lea_membase (code, X86_ESI, ins->inst_basereg, ins->inst_offset);
2593                         else
2594                                 x86_mov_reg_reg (code, X86_ESI, ins->inst_basereg, 4);
2595                         x86_lea_membase (code, X86_EDI, X86_ESP, 12);
2596                         x86_mov_reg_imm (code, X86_ECX, (ins->inst_imm >> 2));
2597                         x86_cld (code);
2598                         x86_prefix (code, X86_REP_PREFIX);
2599                         x86_movsd (code);
2600                         x86_pop_reg (code, X86_ECX);
2601                         x86_pop_reg (code, X86_ESI);
2602                         x86_pop_reg (code, X86_EDI);
2603                         break;
2604                 case OP_X86_LEA:
2605                         x86_lea_memindex (code, ins->dreg, ins->sreg1, ins->inst_imm, ins->sreg2, ins->unused);
2606                         break;
2607                 case OP_X86_LEA_MEMBASE:
2608                         x86_lea_membase (code, ins->dreg, ins->sreg1, ins->inst_imm);
2609                         break;
2610                 case OP_X86_XCHG:
2611                         x86_xchg_reg_reg (code, ins->sreg1, ins->sreg2, 4);
2612                         break;
2613                 case OP_LOCALLOC:
2614                         /* keep alignment */
2615                         x86_alu_reg_imm (code, X86_ADD, ins->sreg1, MONO_ARCH_FRAME_ALIGNMENT - 1);
2616                         x86_alu_reg_imm (code, X86_AND, ins->sreg1, ~(MONO_ARCH_FRAME_ALIGNMENT - 1));
2617                         code = mono_emit_stack_alloc (code, ins);
2618                         x86_mov_reg_reg (code, ins->dreg, X86_ESP, 4);
2619                         break;
2620                 case CEE_RET:
2621                         x86_ret (code);
2622                         break;
2623                 case CEE_THROW: {
2624                         x86_push_reg (code, ins->sreg1);
2625                         mono_add_patch_info (cfg, code - cfg->native_code, MONO_PATCH_INFO_INTERNAL_METHOD, 
2626                                              (gpointer)"mono_arch_throw_exception");
2627                         x86_call_code (code, 0);
2628                         break;
2629                 }
2630                 case OP_CALL_HANDLER: 
2631                         mono_add_patch_info (cfg, code - cfg->native_code, MONO_PATCH_INFO_BB, ins->inst_target_bb);
2632                         x86_call_imm (code, 0);
2633                         break;
2634                 case OP_LABEL:
2635                         ins->inst_c0 = code - cfg->native_code;
2636                         break;
2637                 case CEE_BR:
2638                         //g_print ("target: %p, next: %p, curr: %p, last: %p\n", ins->inst_target_bb, bb->next_bb, ins, bb->last_ins);
2639                         //if ((ins->inst_target_bb == bb->next_bb) && ins == bb->last_ins)
2640                         //break;
2641                         if (ins->flags & MONO_INST_BRLABEL) {
2642                                 if (ins->inst_i0->inst_c0) {
2643                                         x86_jump_code (code, cfg->native_code + ins->inst_i0->inst_c0);
2644                                 } else {
2645                                         mono_add_patch_info (cfg, offset, MONO_PATCH_INFO_LABEL, ins->inst_i0);
2646                                         x86_jump32 (code, 0);
2647                                 }
2648                         } else {
2649                                 if (ins->inst_target_bb->native_offset) {
2650                                         x86_jump_code (code, cfg->native_code + ins->inst_target_bb->native_offset); 
2651                                 } else {
2652                                         mono_add_patch_info (cfg, offset, MONO_PATCH_INFO_BB, ins->inst_target_bb);
2653                                         if ((cfg->opt & MONO_OPT_BRANCH) &&
2654                                             x86_is_imm8 (ins->inst_target_bb->max_offset - cpos))
2655                                                 x86_jump8 (code, 0);
2656                                         else 
2657                                                 x86_jump32 (code, 0);
2658                                 } 
2659                         }
2660                         break;
2661                 case OP_BR_REG:
2662                         x86_jump_reg (code, ins->sreg1);
2663                         break;
2664                 case OP_CEQ:
2665                         x86_set_reg (code, X86_CC_EQ, ins->dreg, TRUE);
2666                         x86_widen_reg (code, ins->dreg, ins->dreg, FALSE, FALSE);
2667                         break;
2668                 case OP_CLT:
2669                         x86_set_reg (code, X86_CC_LT, ins->dreg, TRUE);
2670                         x86_widen_reg (code, ins->dreg, ins->dreg, FALSE, FALSE);
2671                         break;
2672                 case OP_CLT_UN:
2673                         x86_set_reg (code, X86_CC_LT, ins->dreg, FALSE);
2674                         x86_widen_reg (code, ins->dreg, ins->dreg, FALSE, FALSE);
2675                         break;
2676                 case OP_CGT:
2677                         x86_set_reg (code, X86_CC_GT, ins->dreg, TRUE);
2678                         x86_widen_reg (code, ins->dreg, ins->dreg, FALSE, FALSE);
2679                         break;
2680                 case OP_CGT_UN:
2681                         x86_set_reg (code, X86_CC_GT, ins->dreg, FALSE);
2682                         x86_widen_reg (code, ins->dreg, ins->dreg, FALSE, FALSE);
2683                         break;
2684                 case OP_COND_EXC_EQ:
2685                 case OP_COND_EXC_NE_UN:
2686                 case OP_COND_EXC_LT:
2687                 case OP_COND_EXC_LT_UN:
2688                 case OP_COND_EXC_GT:
2689                 case OP_COND_EXC_GT_UN:
2690                 case OP_COND_EXC_GE:
2691                 case OP_COND_EXC_GE_UN:
2692                 case OP_COND_EXC_LE:
2693                 case OP_COND_EXC_LE_UN:
2694                 case OP_COND_EXC_OV:
2695                 case OP_COND_EXC_NO:
2696                 case OP_COND_EXC_C:
2697                 case OP_COND_EXC_NC:
2698                         EMIT_COND_SYSTEM_EXCEPTION (branch_cc_table [ins->opcode - OP_COND_EXC_EQ], 
2699                                                     (ins->opcode < OP_COND_EXC_NE_UN), ins->inst_p1);
2700                         break;
2701                 case CEE_BEQ:
2702                 case CEE_BNE_UN:
2703                 case CEE_BLT:
2704                 case CEE_BLT_UN:
2705                 case CEE_BGT:
2706                 case CEE_BGT_UN:
2707                 case CEE_BGE:
2708                 case CEE_BGE_UN:
2709                 case CEE_BLE:
2710                 case CEE_BLE_UN:
2711                         EMIT_COND_BRANCH (ins, branch_cc_table [ins->opcode - CEE_BEQ], (ins->opcode < CEE_BNE_UN));
2712                         break;
2713
2714                 /* floating point opcodes */
2715                 case OP_R8CONST: {
2716                         double d = *(double *)ins->inst_p0;
2717
2718                         if ((d == 0.0) && (mono_signbit (d) == 0)) {
2719                                 x86_fldz (code);
2720                         } else if (d == 1.0) {
2721                                 x86_fld1 (code);
2722                         } else {
2723                                 mono_add_patch_info (cfg, offset, MONO_PATCH_INFO_R8, ins->inst_p0);
2724                                 x86_fld (code, NULL, TRUE);
2725                         }
2726                         break;
2727                 }
2728                 case OP_R4CONST: {
2729                         float f = *(float *)ins->inst_p0;
2730
2731                         if ((f == 0.0) && (mono_signbit (f) == 0)) {
2732                                 x86_fldz (code);
2733                         } else if (f == 1.0) {
2734                                 x86_fld1 (code);
2735                         } else {
2736                                 mono_add_patch_info (cfg, offset, MONO_PATCH_INFO_R4, ins->inst_p0);
2737                                 x86_fld (code, NULL, FALSE);
2738                         }
2739                         break;
2740                 }
2741                 case OP_STORER8_MEMBASE_REG:
2742                         x86_fst_membase (code, ins->inst_destbasereg, ins->inst_offset, TRUE, TRUE);
2743                         break;
2744                 case OP_LOADR8_SPILL_MEMBASE:
2745                         x86_fld_membase (code, ins->inst_basereg, ins->inst_offset, TRUE);
2746                         x86_fxch (code, 1);
2747                         break;
2748                 case OP_LOADR8_MEMBASE:
2749                         x86_fld_membase (code, ins->inst_basereg, ins->inst_offset, TRUE);
2750                         break;
2751                 case OP_STORER4_MEMBASE_REG:
2752                         x86_fst_membase (code, ins->inst_destbasereg, ins->inst_offset, FALSE, TRUE);
2753                         break;
2754                 case OP_LOADR4_MEMBASE:
2755                         x86_fld_membase (code, ins->inst_basereg, ins->inst_offset, FALSE);
2756                         break;
2757                 case CEE_CONV_R4: /* FIXME: change precision */
2758                 case CEE_CONV_R8:
2759                         x86_push_reg (code, ins->sreg1);
2760                         x86_fild_membase (code, X86_ESP, 0, FALSE);
2761                         x86_alu_reg_imm (code, X86_ADD, X86_ESP, 4);
2762                         break;
2763                 case OP_X86_FP_LOAD_I8:
2764                         x86_fild_membase (code, ins->inst_basereg, ins->inst_offset, TRUE);
2765                         break;
2766                 case OP_X86_FP_LOAD_I4:
2767                         x86_fild_membase (code, ins->inst_basereg, ins->inst_offset, FALSE);
2768                         break;
2769                 case OP_FCONV_TO_I1:
2770                         code = emit_float_to_int (cfg, code, ins->dreg, 1, TRUE);
2771                         break;
2772                 case OP_FCONV_TO_U1:
2773                         code = emit_float_to_int (cfg, code, ins->dreg, 1, FALSE);
2774                         break;
2775                 case OP_FCONV_TO_I2:
2776                         code = emit_float_to_int (cfg, code, ins->dreg, 2, TRUE);
2777                         break;
2778                 case OP_FCONV_TO_U2:
2779                         code = emit_float_to_int (cfg, code, ins->dreg, 2, FALSE);
2780                         break;
2781                 case OP_FCONV_TO_I4:
2782                 case OP_FCONV_TO_I:
2783                         code = emit_float_to_int (cfg, code, ins->dreg, 4, TRUE);
2784                         break;
2785                 case OP_FCONV_TO_I8:
2786                         x86_alu_reg_imm (code, X86_SUB, X86_ESP, 4);
2787                         x86_fnstcw_membase(code, X86_ESP, 0);
2788                         x86_mov_reg_membase (code, ins->dreg, X86_ESP, 0, 2);
2789                         x86_alu_reg_imm (code, X86_OR, ins->dreg, 0xc00);
2790                         x86_mov_membase_reg (code, X86_ESP, 2, ins->dreg, 2);
2791                         x86_fldcw_membase (code, X86_ESP, 2);
2792                         x86_alu_reg_imm (code, X86_SUB, X86_ESP, 8);
2793                         x86_fist_pop_membase (code, X86_ESP, 0, TRUE);
2794                         x86_pop_reg (code, ins->dreg);
2795                         x86_pop_reg (code, ins->unused);
2796                         x86_fldcw_membase (code, X86_ESP, 0);
2797                         x86_alu_reg_imm (code, X86_ADD, X86_ESP, 4);
2798                         break;
2799                 case OP_LCONV_TO_R_UN: { 
2800                         static guint8 mn[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0x3f, 0x40 };
2801                         guint8 *br;
2802
2803                         /* load 64bit integer to FP stack */
2804                         x86_push_imm (code, 0);
2805                         x86_push_reg (code, ins->sreg2);
2806                         x86_push_reg (code, ins->sreg1);
2807                         x86_fild_membase (code, X86_ESP, 0, TRUE);
2808                         /* store as 80bit FP value */
2809                         x86_fst80_membase (code, X86_ESP, 0);
2810                         
2811                         /* test if lreg is negative */
2812                         x86_test_reg_reg (code, ins->sreg2, ins->sreg2);
2813                         br = code; x86_branch8 (code, X86_CC_GEZ, 0, TRUE);
2814         
2815                         /* add correction constant mn */
2816                         x86_fld80_mem (code, mn);
2817                         x86_fld80_membase (code, X86_ESP, 0);
2818                         x86_fp_op_reg (code, X86_FADD, 1, TRUE);
2819                         x86_fst80_membase (code, X86_ESP, 0);
2820
2821                         x86_patch (br, code);
2822
2823                         x86_fld80_membase (code, X86_ESP, 0);
2824                         x86_alu_reg_imm (code, X86_ADD, X86_ESP, 12);
2825
2826                         break;
2827                 }
2828                 case OP_LCONV_TO_OVF_I: {
2829                         guint8 *br [3], *label [1];
2830
2831                         /* 
2832                          * Valid ints: 0xffffffff:8000000 to 00000000:0x7f000000
2833                          */
2834                         x86_test_reg_reg (code, ins->sreg1, ins->sreg1);
2835
2836                         /* If the low word top bit is set, see if we are negative */
2837                         br [0] = code; x86_branch8 (code, X86_CC_LT, 0, TRUE);
2838                         /* We are not negative (no top bit set, check for our top word to be zero */
2839                         x86_test_reg_reg (code, ins->sreg2, ins->sreg2);
2840                         br [1] = code; x86_branch8 (code, X86_CC_EQ, 0, TRUE);
2841                         label [0] = code;
2842
2843                         /* throw exception */
2844                         mono_add_patch_info (cfg, code - cfg->native_code, MONO_PATCH_INFO_EXC, "OverflowException");
2845                         x86_jump32 (code, 0);
2846         
2847                         x86_patch (br [0], code);
2848                         /* our top bit is set, check that top word is 0xfffffff */
2849                         x86_alu_reg_imm (code, X86_CMP, ins->sreg2, 0xffffffff);
2850                 
2851                         x86_patch (br [1], code);
2852                         /* nope, emit exception */
2853                         br [2] = code; x86_branch8 (code, X86_CC_NE, 0, TRUE);
2854                         x86_patch (br [2], label [0]);
2855
2856                         if (ins->dreg != ins->sreg1)
2857                                 x86_mov_reg_reg (code, ins->dreg, ins->sreg1, 4);
2858                         break;
2859                 }
2860                 case OP_FADD:
2861                         x86_fp_op_reg (code, X86_FADD, 1, TRUE);
2862                         break;
2863                 case OP_FSUB:
2864                         x86_fp_op_reg (code, X86_FSUB, 1, TRUE);
2865                         break;          
2866                 case OP_FMUL:
2867                         x86_fp_op_reg (code, X86_FMUL, 1, TRUE);
2868                         break;          
2869                 case OP_FDIV:
2870                         x86_fp_op_reg (code, X86_FDIV, 1, TRUE);
2871                         break;          
2872                 case OP_FNEG:
2873                         x86_fchs (code);
2874                         break;          
2875                 case OP_SIN:
2876                         x86_fsin (code);
2877                         break;          
2878                 case OP_COS:
2879                         x86_fcos (code);
2880                         break;          
2881                 case OP_ABS:
2882                         x86_fabs (code);
2883                         break;          
2884                 case OP_TAN: {
2885                         /* 
2886                          * it really doesn't make sense to inline all this code,
2887                          * it's here just to show that things may not be as simple 
2888                          * as they appear.
2889                          */
2890                         guchar *check_pos, *end_tan, *pop_jump;
2891                         x86_push_reg (code, X86_EAX);
2892                         x86_fptan (code);
2893                         x86_fnstsw (code);
2894                         x86_test_reg_imm (code, X86_EAX, X86_FP_C2);
2895                         check_pos = code;
2896                         x86_branch8 (code, X86_CC_NE, 0, FALSE);
2897                         x86_fstp (code, 0); /* pop the 1.0 */
2898                         end_tan = code;
2899                         x86_jump8 (code, 0);
2900                         x86_fldpi (code);
2901                         x86_fp_op (code, X86_FADD, 0);
2902                         x86_fxch (code, 1);
2903                         x86_fprem1 (code);
2904                         x86_fstsw (code);
2905                         x86_test_reg_imm (code, X86_EAX, X86_FP_C2);
2906                         pop_jump = code;
2907                         x86_branch8 (code, X86_CC_NE, 0, FALSE);
2908                         x86_fstp (code, 1);
2909                         x86_fptan (code);
2910                         x86_patch (pop_jump, code);
2911                         x86_fstp (code, 0); /* pop the 1.0 */
2912                         x86_patch (check_pos, code);
2913                         x86_patch (end_tan, code);
2914                         x86_pop_reg (code, X86_EAX);
2915                         break;
2916                 }
2917                 case OP_ATAN:
2918                         x86_fld1 (code);
2919                         x86_fpatan (code);
2920                         break;          
2921                 case OP_SQRT:
2922                         x86_fsqrt (code);
2923                         break;          
2924                 case OP_X86_FPOP:
2925                         x86_fstp (code, 0);
2926                         break;          
2927                 case OP_FREM: {
2928                         guint8 *l1, *l2;
2929
2930                         x86_push_reg (code, X86_EAX);
2931                         /* we need to exchange ST(0) with ST(1) */
2932                         x86_fxch (code, 1);
2933
2934                         /* this requires a loop, because fprem somtimes 
2935                          * returns a partial remainder */
2936                         l1 = code;
2937                         /* looks like MS is using fprem instead of the IEEE compatible fprem1 */
2938                         /* x86_fprem1 (code); */
2939                         x86_fprem (code);
2940                         x86_fnstsw (code);
2941                         x86_alu_reg_imm (code, X86_AND, X86_EAX, X86_FP_C2);
2942                         l2 = code + 2;
2943                         x86_branch8 (code, X86_CC_NE, l1 - l2, FALSE);
2944
2945                         /* pop result */
2946                         x86_fstp (code, 1);
2947
2948                         x86_pop_reg (code, X86_EAX);
2949                         break;
2950                 }
2951                 case OP_FCOMPARE:
2952                         if (cfg->opt & MONO_OPT_FCMOV) {
2953                                 x86_fcomip (code, 1);
2954                                 x86_fstp (code, 0);
2955                                 break;
2956                         }
2957                         /* this overwrites EAX */
2958                         EMIT_FPCOMPARE(code);
2959                         x86_alu_reg_imm (code, X86_AND, X86_EAX, X86_FP_CC_MASK);
2960                         break;
2961                 case OP_FCEQ:
2962                         if (cfg->opt & MONO_OPT_FCMOV) {
2963                                 /* zeroing the register at the start results in 
2964                                  * shorter and faster code (we can also remove the widening op)
2965                                  */
2966                                 guchar *unordered_check;
2967                                 x86_alu_reg_reg (code, X86_XOR, ins->dreg, ins->dreg);
2968                                 x86_fcomip (code, 1);
2969                                 x86_fstp (code, 0);
2970                                 unordered_check = code;
2971                                 x86_branch8 (code, X86_CC_P, 0, FALSE);
2972                                 x86_set_reg (code, X86_CC_EQ, ins->dreg, FALSE);
2973                                 x86_patch (unordered_check, code);
2974                                 break;
2975                         }
2976                         if (ins->dreg != X86_EAX) 
2977                                 x86_push_reg (code, X86_EAX);
2978
2979                         EMIT_FPCOMPARE(code);
2980                         x86_alu_reg_imm (code, X86_AND, X86_EAX, X86_FP_CC_MASK);
2981                         x86_alu_reg_imm (code, X86_CMP, X86_EAX, 0x4000);
2982                         x86_set_reg (code, X86_CC_EQ, ins->dreg, TRUE);
2983                         x86_widen_reg (code, ins->dreg, ins->dreg, FALSE, FALSE);
2984
2985                         if (ins->dreg != X86_EAX) 
2986                                 x86_pop_reg (code, X86_EAX);
2987                         break;
2988                 case OP_FCLT:
2989                 case OP_FCLT_UN:
2990                         if (cfg->opt & MONO_OPT_FCMOV) {
2991                                 /* zeroing the register at the start results in 
2992                                  * shorter and faster code (we can also remove the widening op)
2993                                  */
2994                                 x86_alu_reg_reg (code, X86_XOR, ins->dreg, ins->dreg);
2995                                 x86_fcomip (code, 1);
2996                                 x86_fstp (code, 0);
2997                                 if (ins->opcode == OP_FCLT_UN) {
2998                                         guchar *unordered_check = code;
2999                                         guchar *jump_to_end;
3000                                         x86_branch8 (code, X86_CC_P, 0, FALSE);
3001                                         x86_set_reg (code, X86_CC_GT, ins->dreg, FALSE);
3002                                         jump_to_end = code;
3003                                         x86_jump8 (code, 0);
3004                                         x86_patch (unordered_check, code);
3005                                         x86_inc_reg (code, ins->dreg);
3006                                         x86_patch (jump_to_end, code);
3007                                 } else {
3008                                         x86_set_reg (code, X86_CC_GT, ins->dreg, FALSE);
3009                                 }
3010                                 break;
3011                         }
3012                         if (ins->dreg != X86_EAX) 
3013                                 x86_push_reg (code, X86_EAX);
3014
3015                         EMIT_FPCOMPARE(code);
3016                         x86_alu_reg_imm (code, X86_AND, X86_EAX, X86_FP_CC_MASK);
3017                         if (ins->opcode == OP_FCLT_UN) {
3018                                 guchar *is_not_zero_check, *end_jump;
3019                                 is_not_zero_check = code;
3020                                 x86_branch8 (code, X86_CC_NZ, 0, TRUE);
3021                                 end_jump = code;
3022                                 x86_jump8 (code, 0);
3023                                 x86_patch (is_not_zero_check, code);
3024                                 x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_CC_MASK);
3025
3026                                 x86_patch (end_jump, code);
3027                         }
3028                         x86_set_reg (code, X86_CC_EQ, ins->dreg, TRUE);
3029                         x86_widen_reg (code, ins->dreg, ins->dreg, FALSE, FALSE);
3030
3031                         if (ins->dreg != X86_EAX) 
3032                                 x86_pop_reg (code, X86_EAX);
3033                         break;
3034                 case OP_FCGT:
3035                 case OP_FCGT_UN:
3036                         if (cfg->opt & MONO_OPT_FCMOV) {
3037                                 /* zeroing the register at the start results in 
3038                                  * shorter and faster code (we can also remove the widening op)
3039                                  */
3040                                 guchar *unordered_check;
3041                                 x86_alu_reg_reg (code, X86_XOR, ins->dreg, ins->dreg);
3042                                 x86_fcomip (code, 1);
3043                                 x86_fstp (code, 0);
3044                                 if (ins->opcode == OP_FCGT) {
3045                                         unordered_check = code;
3046                                         x86_branch8 (code, X86_CC_P, 0, FALSE);
3047                                         x86_set_reg (code, X86_CC_LT, ins->dreg, FALSE);
3048                                         x86_patch (unordered_check, code);
3049                                 } else {
3050                                         x86_set_reg (code, X86_CC_LT, ins->dreg, FALSE);
3051                                 }
3052                                 break;
3053                         }
3054                         if (ins->dreg != X86_EAX) 
3055                                 x86_push_reg (code, X86_EAX);
3056
3057                         EMIT_FPCOMPARE(code);
3058                         x86_alu_reg_imm (code, X86_AND, X86_EAX, X86_FP_CC_MASK);
3059                         x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_C0);
3060                         if (ins->opcode == OP_FCGT_UN) {
3061                                 guchar *is_not_zero_check, *end_jump;
3062                                 is_not_zero_check = code;
3063                                 x86_branch8 (code, X86_CC_NZ, 0, TRUE);
3064                                 end_jump = code;
3065                                 x86_jump8 (code, 0);
3066                                 x86_patch (is_not_zero_check, code);
3067                                 x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_CC_MASK);
3068
3069                                 x86_patch (end_jump, code);
3070                         }
3071                         x86_set_reg (code, X86_CC_EQ, ins->dreg, TRUE);
3072                         x86_widen_reg (code, ins->dreg, ins->dreg, FALSE, FALSE);
3073
3074                         if (ins->dreg != X86_EAX) 
3075                                 x86_pop_reg (code, X86_EAX);
3076                         break;
3077                 case OP_FBEQ:
3078                         if (cfg->opt & MONO_OPT_FCMOV) {
3079                                 guchar *jump = code;
3080                                 x86_branch8 (code, X86_CC_P, 0, TRUE);
3081                                 EMIT_COND_BRANCH (ins, X86_CC_EQ, FALSE);
3082                                 x86_patch (jump, code);
3083                                 break;
3084                         }
3085                         x86_alu_reg_imm (code, X86_CMP, X86_EAX, 0x4000);
3086                         EMIT_COND_BRANCH (ins, X86_CC_EQ, TRUE);
3087                         break;
3088                 case OP_FBNE_UN:
3089                         /* Branch if C013 != 100 */
3090                         if (cfg->opt & MONO_OPT_FCMOV) {
3091                                 /* branch if !ZF or (PF|CF) */
3092                                 EMIT_COND_BRANCH (ins, X86_CC_NE, FALSE);
3093                                 EMIT_COND_BRANCH (ins, X86_CC_P, FALSE);
3094                                 EMIT_COND_BRANCH (ins, X86_CC_B, FALSE);
3095                                 break;
3096                         }
3097                         x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_C3);
3098                         EMIT_COND_BRANCH (ins, X86_CC_NE, FALSE);
3099                         break;
3100                 case OP_FBLT:
3101                         if (cfg->opt & MONO_OPT_FCMOV) {
3102                                 EMIT_COND_BRANCH (ins, X86_CC_GT, FALSE);
3103                                 break;
3104                         }
3105                         EMIT_COND_BRANCH (ins, X86_CC_EQ, FALSE);
3106                         break;
3107                 case OP_FBLT_UN:
3108                         if (cfg->opt & MONO_OPT_FCMOV) {
3109                                 EMIT_COND_BRANCH (ins, X86_CC_P, FALSE);
3110                                 EMIT_COND_BRANCH (ins, X86_CC_GT, FALSE);
3111                                 break;
3112                         }
3113                         if (ins->opcode == OP_FBLT_UN) {
3114                                 guchar *is_not_zero_check, *end_jump;
3115                                 is_not_zero_check = code;
3116                                 x86_branch8 (code, X86_CC_NZ, 0, TRUE);
3117                                 end_jump = code;
3118                                 x86_jump8 (code, 0);
3119                                 x86_patch (is_not_zero_check, code);
3120                                 x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_CC_MASK);
3121
3122                                 x86_patch (end_jump, code);
3123                         }
3124                         EMIT_COND_BRANCH (ins, X86_CC_EQ, FALSE);
3125                         break;
3126                 case OP_FBGT:
3127                 case OP_FBGT_UN:
3128                         if (cfg->opt & MONO_OPT_FCMOV) {
3129                                 EMIT_COND_BRANCH (ins, X86_CC_LT, FALSE);
3130                                 break;
3131                         }
3132                         x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_C0);
3133                         if (ins->opcode == OP_FBGT_UN) {
3134                                 guchar *is_not_zero_check, *end_jump;
3135                                 is_not_zero_check = code;
3136                                 x86_branch8 (code, X86_CC_NZ, 0, TRUE);
3137                                 end_jump = code;
3138                                 x86_jump8 (code, 0);
3139                                 x86_patch (is_not_zero_check, code);
3140                                 x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_CC_MASK);
3141
3142                                 x86_patch (end_jump, code);
3143                         }
3144                         EMIT_COND_BRANCH (ins, X86_CC_EQ, FALSE);
3145                         break;
3146                 case OP_FBGE:
3147                         /* Branch if C013 == 100 or 001 */
3148                         if (cfg->opt & MONO_OPT_FCMOV) {
3149                                 guchar *br1;
3150
3151                                 /* skip branch if C1=1 */
3152                                 br1 = code;
3153                                 x86_branch8 (code, X86_CC_P, 0, FALSE);
3154                                 /* branch if (C0 | C3) = 1 */
3155                                 EMIT_COND_BRANCH (ins, X86_CC_BE, FALSE);
3156                                 x86_patch (br1, code);
3157                                 break;
3158                         }
3159                         x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_C0);
3160                         EMIT_COND_BRANCH (ins, X86_CC_EQ, FALSE);
3161                         x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_C3);
3162                         EMIT_COND_BRANCH (ins, X86_CC_EQ, FALSE);
3163                         break;
3164                 case OP_FBGE_UN:
3165                         /* Branch if C013 == 000 */
3166                         if (cfg->opt & MONO_OPT_FCMOV) {
3167                                 EMIT_COND_BRANCH (ins, X86_CC_LE, FALSE);
3168                                 break;
3169                         }
3170                         EMIT_COND_BRANCH (ins, X86_CC_NE, FALSE);
3171                         break;
3172                 case OP_FBLE:
3173                         /* Branch if C013=000 or 100 */
3174                         if (cfg->opt & MONO_OPT_FCMOV) {
3175                                 guchar *br1;
3176
3177                                 /* skip branch if C1=1 */
3178                                 br1 = code;
3179                                 x86_branch8 (code, X86_CC_P, 0, FALSE);
3180                                 /* branch if C0=0 */
3181                                 EMIT_COND_BRANCH (ins, X86_CC_NB, FALSE);
3182                                 x86_patch (br1, code);
3183                                 break;
3184                         }
3185                         x86_alu_reg_imm (code, X86_AND, X86_EAX, (X86_FP_C0|X86_FP_C1));
3186                         x86_alu_reg_imm (code, X86_CMP, X86_EAX, 0);
3187                         EMIT_COND_BRANCH (ins, X86_CC_EQ, FALSE);
3188                         break;
3189                 case OP_FBLE_UN:
3190                         /* Branch if C013 != 001 */
3191                         if (cfg->opt & MONO_OPT_FCMOV) {
3192                                 EMIT_COND_BRANCH (ins, X86_CC_P, FALSE);
3193                                 EMIT_COND_BRANCH (ins, X86_CC_GE, FALSE);
3194                                 break;
3195                         }
3196                         x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_C0);
3197                         EMIT_COND_BRANCH (ins, X86_CC_NE, FALSE);
3198                         break;
3199                 case CEE_CKFINITE: {
3200                         x86_push_reg (code, X86_EAX);
3201                         x86_fxam (code);
3202                         x86_fnstsw (code);
3203                         x86_alu_reg_imm (code, X86_AND, X86_EAX, 0x4100);
3204                         x86_alu_reg_imm (code, X86_CMP, X86_EAX, X86_FP_C0);
3205                         x86_pop_reg (code, X86_EAX);
3206                         EMIT_COND_SYSTEM_EXCEPTION (X86_CC_EQ, FALSE, "ArithmeticException");
3207                         break;
3208                 }
3209                 default:
3210                         g_warning ("unknown opcode %s in %s()\n", mono_inst_name (ins->opcode), __FUNCTION__);
3211                         g_assert_not_reached ();
3212                 }
3213
3214                 if ((code - cfg->native_code - offset) > max_len) {
3215                         g_warning ("wrong maximal instruction length of instruction %s (expected %d, got %d)",
3216                                    mono_inst_name (ins->opcode), max_len, code - cfg->native_code - offset);
3217                         g_assert_not_reached ();
3218                 }
3219                
3220                 cpos += max_len;
3221
3222                 last_ins = ins;
3223                 last_offset = offset;
3224                 
3225                 ins = ins->next;
3226         }
3227
3228         cfg->code_len = code - cfg->native_code;
3229 }
3230
3231 void
3232 mono_arch_register_lowlevel_calls (void)
3233 {
3234         mono_register_jit_icall (mono_arch_get_lmf_addr, "mono_arch_get_lmf_addr", NULL, TRUE);
3235 }
3236
3237 void
3238 mono_arch_patch_code (MonoMethod *method, MonoDomain *domain, guint8 *code, MonoJumpInfo *ji, gboolean run_cctors)
3239 {
3240         MonoJumpInfo *patch_info;
3241
3242         for (patch_info = ji; patch_info; patch_info = patch_info->next) {
3243                 unsigned char *ip = patch_info->ip.i + code;
3244                 const unsigned char *target;
3245
3246                 target = mono_resolve_patch_target (method, domain, code, patch_info, run_cctors);
3247
3248                 switch (patch_info->type) {
3249                 case MONO_PATCH_INFO_IP:
3250                         *((gconstpointer *)(ip)) = target;
3251                         continue;
3252                 case MONO_PATCH_INFO_METHOD_REL:
3253                         *((gconstpointer *)(ip)) = target;
3254                         continue;
3255                 case MONO_PATCH_INFO_SWITCH: {
3256                         *((gconstpointer *)(ip + 2)) = target;
3257                         /* we put into the table the absolute address, no need for x86_patch in this case */
3258                         continue;
3259                 }
3260                 case MONO_PATCH_INFO_IID:
3261                         *((guint32 *)(ip + 1)) = (guint32)target;
3262                         continue;                       
3263                 case MONO_PATCH_INFO_CLASS_INIT: {
3264                         guint8 *code = ip;
3265                         /* Might already been changed to a nop */
3266                         x86_call_imm (code, 0);
3267                         break;
3268                 }
3269                 case MONO_PATCH_INFO_R4:
3270                 case MONO_PATCH_INFO_R8:
3271                         *((gconstpointer *)(ip + 2)) = target;
3272                         continue;
3273                 case MONO_PATCH_INFO_METHODCONST:
3274                 case MONO_PATCH_INFO_CLASS:
3275                 case MONO_PATCH_INFO_IMAGE:
3276                 case MONO_PATCH_INFO_FIELD:
3277                 case MONO_PATCH_INFO_VTABLE:
3278                 case MONO_PATCH_INFO_SFLDA:
3279                 case MONO_PATCH_INFO_EXC_NAME:
3280                 case MONO_PATCH_INFO_LDSTR:
3281                 case MONO_PATCH_INFO_TYPE_FROM_HANDLE:
3282                 case MONO_PATCH_INFO_LDTOKEN:
3283                         *((gconstpointer *)(ip + 1)) = target;
3284                         continue;
3285                 default:
3286                         break;
3287                 }
3288                 x86_patch (ip, target);
3289         }
3290 }
3291
3292 int
3293 mono_arch_max_epilog_size (MonoCompile *cfg)
3294 {
3295         int exc_count = 0, max_epilog_size = 16;
3296         MonoJumpInfo *patch_info;
3297         
3298         if (cfg->method->save_lmf)
3299                 max_epilog_size += 128;
3300         
3301         if (mono_jit_trace_calls != NULL)
3302                 max_epilog_size += 50;
3303
3304         if (cfg->prof_options & MONO_PROFILE_ENTER_LEAVE)
3305                 max_epilog_size += 50;
3306
3307         /* count the number of exception infos */
3308      
3309         for (patch_info = cfg->patch_info; patch_info; patch_info = patch_info->next) {
3310                 if (patch_info->type == MONO_PATCH_INFO_EXC)
3311                         exc_count++;
3312         }
3313
3314         /* 
3315          * make sure we have enough space for exceptions
3316          * 16 is the size of two push_imm instructions and a call
3317          */
3318         max_epilog_size += exc_count*16;
3319
3320         return max_epilog_size;
3321 }
3322
3323 guint8 *
3324 mono_arch_emit_prolog (MonoCompile *cfg)
3325 {
3326         MonoMethod *method = cfg->method;
3327         MonoBasicBlock *bb;
3328         MonoMethodSignature *sig;
3329         MonoInst *inst;
3330         int alloc_size, pos, max_offset, i;
3331         guint8 *code;
3332
3333         cfg->code_size =  MAX (((MonoMethodNormal *)method)->header->code_size * 4, 256);
3334         code = cfg->native_code = g_malloc (cfg->code_size);
3335
3336         x86_push_reg (code, X86_EBP);
3337         x86_mov_reg_reg (code, X86_EBP, X86_ESP, 4);
3338
3339         alloc_size = - cfg->stack_offset;
3340         pos = 0;
3341
3342         if (method->save_lmf) {
3343                 pos += sizeof (MonoLMF);
3344
3345                 /* save the current IP */
3346                 mono_add_patch_info (cfg, code + 1 - cfg->native_code, MONO_PATCH_INFO_IP, NULL);
3347                 x86_push_imm (code, 0);
3348
3349                 /* save all caller saved regs */
3350                 x86_push_reg (code, X86_EBX);
3351                 x86_push_reg (code, X86_EDI);
3352                 x86_push_reg (code, X86_ESI);
3353                 x86_push_reg (code, X86_EBP);
3354
3355                 /* save method info */
3356                 x86_push_imm (code, method);
3357
3358                 /* get the address of lmf for the current thread */
3359                 /* 
3360                  * This is performance critical so we try to use some tricks to make
3361                  * it fast.
3362                  */
3363                 if (lmf_tls_offset != -1) {
3364                         /* Load lmf quicky using the GS register */
3365                         x86_prefix (code, X86_GS_PREFIX);
3366                         x86_mov_reg_mem (code, X86_EAX, 0, 4);
3367                         x86_mov_reg_membase (code, X86_EAX, X86_EAX, lmf_tls_offset, 4);
3368                 }
3369                 else {
3370 #ifdef HAVE_KW_THREAD
3371                         mono_add_patch_info (cfg, code - cfg->native_code, MONO_PATCH_INFO_INTERNAL_METHOD, 
3372                                                                  (gpointer)"mono_arch_get_lmf_addr");
3373 #else
3374                         mono_add_patch_info (cfg, code - cfg->native_code, MONO_PATCH_INFO_INTERNAL_METHOD, 
3375                                                                  (gpointer)"mono_get_lmf_addr");
3376 #endif
3377                         x86_call_code (code, 0);
3378                 }
3379
3380                 /* push lmf */
3381                 x86_push_reg (code, X86_EAX); 
3382                 /* push *lfm (previous_lmf) */
3383                 x86_push_membase (code, X86_EAX, 0);
3384                 /* *(lmf) = ESP */
3385                 x86_mov_membase_reg (code, X86_EAX, 0, X86_ESP, 4);
3386         } else {
3387
3388                 if (cfg->used_int_regs & (1 << X86_EBX)) {
3389                         x86_push_reg (code, X86_EBX);
3390                         pos += 4;
3391                 }
3392
3393                 if (cfg->used_int_regs & (1 << X86_EDI)) {
3394                         x86_push_reg (code, X86_EDI);
3395                         pos += 4;
3396                 }
3397
3398                 if (cfg->used_int_regs & (1 << X86_ESI)) {
3399                         x86_push_reg (code, X86_ESI);
3400                         pos += 4;
3401                 }
3402         }
3403
3404         alloc_size -= pos;
3405
3406         if (alloc_size) {
3407                 /* See mono_emit_stack_alloc */
3408 #ifdef PLATFORM_WIN32
3409                 guint32 remaining_size = alloc_size;
3410                 while (remaining_size >= 0x1000) {
3411                         x86_alu_reg_imm (code, X86_SUB, X86_ESP, 0x1000);
3412                         x86_test_membase_reg (code, X86_ESP, 0, X86_ESP);
3413                         remaining_size -= 0x1000;
3414                 }
3415                 if (remaining_size)
3416                         x86_alu_reg_imm (code, X86_SUB, X86_ESP, remaining_size);
3417 #else
3418                 x86_alu_reg_imm (code, X86_SUB, X86_ESP, alloc_size);
3419 #endif
3420         }
3421
3422         /* compute max_offset in order to use short forward jumps */
3423         max_offset = 0;
3424         if (cfg->opt & MONO_OPT_BRANCH) {
3425                 for (bb = cfg->bb_entry; bb; bb = bb->next_bb) {
3426                         MonoInst *ins = bb->code;
3427                         bb->max_offset = max_offset;
3428
3429                         if (cfg->prof_options & MONO_PROFILE_COVERAGE)
3430                                 max_offset += 6; 
3431
3432                         while (ins) {
3433                                 max_offset += ((guint8 *)ins_spec [ins->opcode])[MONO_INST_LEN];
3434                                 ins = ins->next;
3435                         }
3436                 }
3437         }
3438
3439         if (mono_jit_trace_calls != NULL && mono_trace_eval (method))
3440                 code = mono_arch_instrument_prolog (cfg, mono_trace_enter_method, code, TRUE);
3441
3442         /* load arguments allocated to register from the stack */
3443         sig = method->signature;
3444         pos = 0;
3445
3446         for (i = 0; i < sig->param_count + sig->hasthis; ++i) {
3447                 inst = cfg->varinfo [pos];
3448                 if (inst->opcode == OP_REGVAR) {
3449                         x86_mov_reg_membase (code, inst->dreg, X86_EBP, inst->inst_offset, 4);
3450                         if (cfg->verbose_level > 2)
3451                                 g_print ("Argument %d assigned to register %s\n", pos, mono_arch_regname (inst->dreg));
3452                 }
3453                 pos++;
3454         }
3455
3456         cfg->code_len = code - cfg->native_code;
3457
3458         return code;
3459 }
3460
3461 void
3462 mono_arch_emit_epilog (MonoCompile *cfg)
3463 {
3464         MonoJumpInfo *patch_info;
3465         MonoMethod *method = cfg->method;
3466         MonoMethodSignature *sig = method->signature;
3467         int pos;
3468         guint32 stack_to_pop;
3469         guint8 *code;
3470
3471         code = cfg->native_code + cfg->code_len;
3472
3473         if (mono_jit_trace_calls != NULL && mono_trace_eval (method))
3474                 code = mono_arch_instrument_epilog (cfg, mono_trace_leave_method, code, TRUE);
3475
3476         /* the code restoring the registers must be kept in sync with CEE_JMP */
3477         pos = 0;
3478         
3479         if (method->save_lmf) {
3480                 pos = -sizeof (MonoLMF);
3481         } else {
3482                 if (cfg->used_int_regs & (1 << X86_EBX)) {
3483                         pos -= 4;
3484                 }
3485                 if (cfg->used_int_regs & (1 << X86_EDI)) {
3486                         pos -= 4;
3487                 }
3488                 if (cfg->used_int_regs & (1 << X86_ESI)) {
3489                         pos -= 4;
3490                 }
3491         }
3492
3493         if (pos)
3494                 x86_lea_membase (code, X86_ESP, X86_EBP, pos);
3495         
3496         if (method->save_lmf) {
3497                 /* ebx = previous_lmf */
3498                 x86_pop_reg (code, X86_EBX);
3499                 /* edi = lmf */
3500                 x86_pop_reg (code, X86_EDI);
3501                 /* *(lmf) = previous_lmf */
3502                 x86_mov_membase_reg (code, X86_EDI, 0, X86_EBX, 4);
3503
3504                 /* discard method info */
3505                 x86_pop_reg (code, X86_ESI);
3506
3507                 /* restore caller saved regs */
3508                 x86_pop_reg (code, X86_EBP);
3509                 x86_pop_reg (code, X86_ESI);
3510                 x86_pop_reg (code, X86_EDI);
3511                 x86_pop_reg (code, X86_EBX);
3512
3513         } else {
3514
3515                 if (cfg->used_int_regs & (1 << X86_ESI)) {
3516                         x86_pop_reg (code, X86_ESI);
3517                 }
3518                 if (cfg->used_int_regs & (1 << X86_EDI)) {
3519                         x86_pop_reg (code, X86_EDI);
3520                 }
3521                 if (cfg->used_int_regs & (1 << X86_EBX)) {
3522                         x86_pop_reg (code, X86_EBX);
3523                 }
3524         }
3525
3526         x86_leave (code);
3527
3528         if (CALLCONV_IS_STDCALL (sig->call_convention)) {
3529                 MonoJitArgumentInfo *arg_info = alloca (sizeof (MonoJitArgumentInfo) * (sig->param_count + 1));
3530
3531                 stack_to_pop = mono_arch_get_argument_info (sig, sig->param_count, arg_info);
3532         } else if (MONO_TYPE_ISSTRUCT (cfg->method->signature->ret))
3533                 stack_to_pop = 4;
3534         else
3535                 stack_to_pop = 0;
3536
3537         if (stack_to_pop)
3538                 x86_ret_imm (code, stack_to_pop);
3539         else
3540                 x86_ret (code);
3541
3542         /* add code to raise exceptions */
3543         for (patch_info = cfg->patch_info; patch_info; patch_info = patch_info->next) {
3544                 switch (patch_info->type) {
3545                 case MONO_PATCH_INFO_EXC:
3546                         x86_patch (patch_info->ip.i + cfg->native_code, code);
3547                         mono_add_patch_info (cfg, code - cfg->native_code, MONO_PATCH_INFO_EXC_NAME, patch_info->data.target);
3548                         x86_push_imm (code, patch_info->data.target);
3549                         mono_add_patch_info (cfg, code + 1 - cfg->native_code, MONO_PATCH_INFO_METHOD_REL, (gpointer)patch_info->ip.i);
3550                         x86_push_imm (code, patch_info->ip.i + cfg->native_code);
3551                         patch_info->type = MONO_PATCH_INFO_INTERNAL_METHOD;
3552                         patch_info->data.name = "mono_arch_throw_exception_by_name";
3553                         patch_info->ip.i = code - cfg->native_code;
3554                         x86_jump_code (code, 0);
3555                         break;
3556                 default:
3557                         /* do nothing */
3558                         break;
3559                 }
3560         }
3561
3562         cfg->code_len = code - cfg->native_code;
3563
3564         g_assert (cfg->code_len < cfg->code_size);
3565
3566 }
3567
3568 void
3569 mono_arch_flush_icache (guint8 *code, gint size)
3570 {
3571         /* not needed */
3572 }
3573
3574 void
3575 mono_arch_flush_register_windows (void)
3576 {
3577 }
3578
3579 /*
3580  * Support for fast access to the thread-local lmf structure using the GS
3581  * segment register on NPTL + kernel 2.6.x.
3582  */
3583
3584 static gboolean tls_offset_inited = FALSE;
3585
3586 #ifdef HAVE_KW_THREAD
3587 static __thread gpointer mono_lmf_addr;
3588 #endif
3589
3590 static gpointer
3591 mono_arch_get_lmf_addr (void)
3592 {
3593 #ifdef HAVE_KW_THREAD
3594         return mono_lmf_addr;
3595 #else
3596         g_assert_not_reached ();
3597         return NULL;
3598 #endif
3599 }
3600
3601 void
3602 mono_arch_setup_jit_tls_data (MonoJitTlsData *tls)
3603 {
3604 #ifdef MONO_ARCH_SIGSEGV_ON_ALTSTACK
3605         pthread_t self = pthread_self();
3606         pthread_attr_t attr;
3607         void *staddr = NULL;
3608         size_t stsize = 0;
3609         struct sigaltstack sa;
3610 #endif
3611
3612         if (!tls_offset_inited) {
3613                 guint8 *code;
3614
3615                 tls_offset_inited = TRUE;
3616
3617                 if (getenv ("MONO_NPTL")) {
3618                         /* 
3619                          * Determine the offset of mono_lfm_addr inside the TLS structures
3620                          * by disassembling the function above.
3621                          */
3622                         code = (guint8*)&mono_arch_get_lmf_addr;
3623
3624                         /* This is generated by gcc 3.3.2 */
3625                         if ((code [0] == 0x55) && (code [1] == 0x89) && (code [2] == 0xe5) &&
3626                                 (code [3] == 0x65) && (code [4] == 0xa1) && (code [5] == 0x00) &&
3627                                 (code [6] == 0x00) && (code [7] == 0x00) && (code [8] == 0x00) &&
3628                                 (code [9] == 0x8b) && (code [10] == 0x80)) {
3629                                 lmf_tls_offset = *(int*)&(code [11]);
3630                         }
3631                 }
3632         }               
3633
3634 #ifdef MONO_ARCH_SIGSEGV_ON_ALTSTACK
3635
3636         /* Determine stack boundaries */
3637         if (!mono_running_on_valgrind ()) {
3638 #ifdef HAVE_PTHREAD_GETATTR_NP
3639                 pthread_getattr_np( self, &attr );
3640 #else
3641 #ifdef HAVE_PTHREAD_ATTR_GET_NP
3642                 pthread_attr_get_np( self, &attr );
3643 #else
3644 #error "Not implemented"
3645 #endif
3646 #endif
3647                 pthread_attr_getstack( &attr, &staddr, &stsize );
3648         }
3649
3650         /* 
3651          * staddr seems to be wrong for the main thread, so we keep the value in
3652          * tls->end_of_stack
3653          */
3654         tls->stack_size = stsize;
3655
3656         /* Setup an alternate signal stack */
3657         tls->signal_stack = g_malloc (SIGNAL_STACK_SIZE);
3658         tls->signal_stack_size = SIGNAL_STACK_SIZE;
3659
3660         sa.ss_sp = tls->signal_stack;
3661         sa.ss_size = SIGNAL_STACK_SIZE;
3662         sa.ss_flags = SS_ONSTACK;
3663         sigaltstack (&sa, NULL);
3664 #endif
3665
3666 #ifdef HAVE_KW_THREAD
3667         mono_lmf_addr = &tls->lmf;
3668 #endif
3669 }
3670
3671 void
3672 mono_arch_free_jit_tls_data (MonoJitTlsData *tls)
3673 {
3674 #ifdef MONO_ARCH_SIGSEGV_ON_ALTSTACK
3675         struct sigaltstack sa;
3676
3677         sa.ss_sp = tls->signal_stack;
3678         sa.ss_size = SIGNAL_STACK_SIZE;
3679         sa.ss_flags = SS_DISABLE;
3680         sigaltstack  (&sa, NULL);
3681
3682         if (tls->signal_stack)
3683                 g_free (tls->signal_stack);
3684 #endif
3685 }
3686
3687 void
3688 mono_arch_emit_this_vret_args (MonoCompile *cfg, MonoCallInst *inst, int this_reg, int this_type, int vt_reg)
3689 {
3690
3691         /* add the this argument */
3692         if (this_reg != -1) {
3693                 MonoInst *this;
3694                 MONO_INST_NEW (cfg, this, OP_OUTARG);
3695                 this->type = this_type;
3696                 this->sreg1 = this_reg;
3697                 mono_bblock_add_inst (cfg->cbb, this);
3698         }
3699
3700         if (vt_reg != -1) {
3701                 MonoInst *vtarg;
3702                 MONO_INST_NEW (cfg, vtarg, OP_OUTARG);
3703                 vtarg->type = STACK_MP;
3704                 vtarg->sreg1 = vt_reg;
3705                 mono_bblock_add_inst (cfg->cbb, vtarg);
3706         }
3707 }
3708
3709
3710 gint
3711 mono_arch_get_opcode_for_method (MonoCompile *cfg, MonoMethod *cmethod, MonoMethodSignature *fsig, MonoInst **args)
3712 {
3713         if (cmethod->klass == mono_defaults.math_class) {
3714                 if (strcmp (cmethod->name, "Sin") == 0)
3715                         return OP_SIN;
3716                 else if (strcmp (cmethod->name, "Cos") == 0)
3717                         return OP_COS;
3718                 else if (strcmp (cmethod->name, "Tan") == 0)
3719                         return OP_TAN;
3720                 else if (strcmp (cmethod->name, "Atan") == 0)
3721                         return OP_ATAN;
3722                 else if (strcmp (cmethod->name, "Sqrt") == 0)
3723                         return OP_SQRT;
3724                 else if (strcmp (cmethod->name, "Abs") == 0 && fsig->params [0]->type == MONO_TYPE_R8)
3725                         return OP_ABS;
3726 #if 0
3727                 /* OP_FREM is not IEEE compatible */
3728                 else if (strcmp (cmethod->name, "IEEERemainder") == 0)
3729                         return OP_FREM;
3730 #endif
3731                 else
3732                         return -1;
3733         } else {
3734                 return -1;
3735         }
3736         return -1;
3737 }
3738
3739
3740 gboolean
3741 mono_arch_print_tree (MonoInst *tree, int arity)
3742 {
3743         return 0;
3744 }