2 * tramp-mips.c: JIT trampoline code for MIPS
5 * Mark Mason (mason@broadcom.com)
7 * Based on tramp-ppc.c by:
8 * Dietmar Maurer (dietmar@ximian.com)
9 * Paolo Molaro (lupus@ximian.com)
10 * Carlos Valiente <yo@virutass.net>
13 * (C) 2001 Ximian, Inc.
19 #include <mono/metadata/appdomain.h>
20 #include <mono/metadata/marshal.h>
21 #include <mono/metadata/tabledefs.h>
22 #include <mono/arch/mips/mips-codegen.h>
25 #include "mini-mips.h"
28 * get_unbox_trampoline:
30 * @addr: pointer to native code for @m
32 * when value type methods are called through the vtable we need to unbox the
33 * this argument. This method returns a pointer to a trampoline which does
34 * unboxing before calling the method
37 mono_arch_get_unbox_trampoline (MonoMethod *m, gpointer addr)
40 int this_pos = mips_a0;
41 MonoDomain *domain = mono_domain_get ();
43 if (!mono_method_signature (m)->ret->byref && MONO_TYPE_ISSTRUCT (mono_method_signature (m)->ret))
46 mono_domain_lock (domain);
47 start = code = mono_code_manager_reserve (domain->code_mp, 20);
48 mono_domain_unlock (domain);
50 mips_load (code, mips_t9, addr);
51 mips_addiu (code, this_pos, this_pos, sizeof (MonoObject));
52 mips_jr (code, mips_t9);
55 mono_arch_flush_icache (start, code - start);
56 g_assert ((code - start) <= 20);
57 /*g_print ("unbox trampoline at %d for %s:%s\n", this_pos, m->klass->name, m->name);
58 g_print ("unbox code is at %p for method at %p\n", start, addr);*/
64 mono_arch_patch_callsite (guint8 *method_start, guint8 *orig_code, guint8 *addr)
66 guint32 *code = (guint32*)orig_code;
68 /* Locate the address of the method-specific trampoline. The call using
69 the vtable slot that took the processing flow to 'arch_create_jit_trampoline'
70 looks something like this:
79 On entry, 'code' points just after one of the above sequences.
83 if ((code[-2] >> 26) == 0x03) {
84 //g_print ("direct patching\n");
85 mips_patch ((code-2), (gsize)addr);
87 /* Sanity check: look for the jalr */
88 g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
90 //printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
92 /* The lui / addiu / jalr case */
93 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
94 mips_patch ((code-4), (gsize)addr);
96 g_assert_not_reached ();
102 mono_arch_patch_plt_entry (guint8 *code, guint8 *addr)
104 g_assert_not_reached ();
107 /* Stack size for trampoline function
108 * MIPS_MINIMAL_STACK_SIZE + 16 (args + alignment to mips_magic_trampoline)
109 * + MonoLMF + 14 fp regs + 13 gregs + alignment
110 * #define STACK (MIPS_MINIMAL_STACK_SIZE + 4 * sizeof (gulong) + sizeof (MonoLMF) + 14 * sizeof (double) + 13 * (sizeof (gulong)))
111 * STACK would be 444 for 32 bit darwin
114 #define STACK (4*4 + 8 + sizeof(MonoLMF) + 32)
117 mono_arch_get_vcall_slot_addr (guint8* code8, gpointer *regs)
122 guint32 *code = (guint32*)code8;
125 /* On MIPS, we are passed sp instead of the register array */
128 //printf ("mips_magic_trampoline: 0x%08x @ 0x%0x\n", *(code-2), code-2);
131 if ((code[-2] >> 26) == 0x03)
134 /* Sanity check: look for the jalr */
135 g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
137 reg = (code[-2] >> 21) & 0x1f;
139 //printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
141 /* The lui / addiu / jalr case */
142 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
146 /* Probably a vtable lookup */
148 /* Walk backwards to find 'lw reg,XX(base)' */
150 guint32 mask = (0x3f << 26) | (0x1f << 16);
151 guint32 match = (0x23 << 26) | (reg << 16);
152 if((*code & mask) == match) {
156 /* lw reg,XX(base) */
157 base = (*code >> 21) & 0x1f;
158 soff = (*code & 0xffff);
162 reg_offset = STACK - sizeof (MonoLMF)
163 + G_STRUCT_OFFSET (MonoLMF, iregs[base]);
164 /* o contains now the value of register reg */
165 vtable = *((char**) (sp + reg_offset));
166 return (gpointer*)vtable;
170 g_assert_not_reached ();
175 mono_arch_nullify_plt_entry (guint8 *code)
177 g_assert_not_reached ();
181 * mips_magic_trampoline:
182 * @code: pointer into caller code
183 * @method: the method to translate
186 * This method is called by the function 'arch_create_jit_trampoline', which in
187 * turn is called by the trampoline functions for virtual methods.
188 * After having called the JIT compiler to compile the method, it inspects the
189 * caller code to find the address of the method-specific part of the
190 * trampoline vtable slot for this method, updates it with a fragment that calls
191 * the newly compiled code and returns this address of the compiled code to
192 * 'arch_create_jit_trampoline'
196 mips_magic_trampoline (MonoMethod *method, guint32 *code, char *sp)
200 MonoJitInfo *ji, *target_ji;
204 addr = mono_compile_method (method);
210 /* We can't trampoline across domains */
211 ji = mono_jit_info_table_find (mono_domain_get (), code);
212 target_ji = mono_jit_info_table_find (mono_domain_get (), addr);
213 if (!mono_method_same_domain (ji, target_ji))
217 g_print ("mips_magic: method code at %p from %p for %s:%s\n",
218 addr, code, method->klass->name, method->name);
220 /* Locate the address of the method-specific trampoline. The call using
221 the vtable slot that took the processing flow to 'arch_create_jit_trampoline'
222 looks something like this:
231 On entry, 'code' points just after one of the above sequences.
235 if ((code[-2] >> 26) == 0x03) {
236 g_print ("direct patching\n");
237 mips_patch ((char*)(code-2), addr);
241 /* Sanity check: look for the jalr */
242 g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
244 reg = (code[-2] >> 21) & 0x1f;
246 //printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
248 /* The lui / addiu / jalr case */
249 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
250 mips_patch ((char*)(code-4), addr);
254 //printf ("mips_magic_trampoline: 0x%08x @ 0x%0x\n", *(code-2), code-2);
256 /* Probably a vtable lookup */
258 /* Walk backwards to find 'lw reg,XX(base)' */
260 guint32 mask = (0x3f << 26) | (0x1f << 16);
261 guint32 match = (0x23 << 26) | (reg << 16);
262 if((*code & mask) == match) {
266 /* lw reg,XX(base) */
267 base = (*code >> 21) & 0x1f;
268 soff = (*code & 0xffff);
272 reg_offset = STACK - sizeof (MonoLMF)
273 + G_STRUCT_OFFSET (MonoLMF, iregs[base]);
274 /* o contains now the value of register reg */
275 vtable = *((char**) (sp + reg_offset));
277 g_print ("patching reg is %d, offset %d (vtable %p) @ %p\n",
278 base, offset, vtable, code);
284 /* this is not done for non-virtual calls, because in that case
285 we won't have an object, but the actual pointer to the
286 valuetype as the this argument
288 if (method->klass->valuetype && !mono_aot_is_got_entry (code, vtable))
289 addr = get_unbox_trampoline (method, addr);
292 if (mono_aot_is_got_entry (code, vtable) || mono_domain_owns_vtable_slot (mono_domain_get (), vtable))
293 *((gpointer *)vtable) = addr;
299 mono_arch_nullify_class_init_trampoline (guint8 *code, gssize *regs)
301 guint32 *code32 = (guint32*)code;
303 /* back up to the jal/jalr instruction */
306 /* Check for jal/jalr -- and NOP it out */
307 if ((((*code32)&0xfc000000) == 0x0c000000)
308 || (((*code32)&0xfc1f003f) == 0x00000009)) {
310 mono_arch_flush_icache ((gpointer)(code32 - 1), 4);
313 g_assert_not_reached ();
318 * Stack frame description when the generic trampoline is called.
320 * --------------------
322 * -------------------
323 * Saved FP registers 0-13
324 * -------------------
325 * Saved general registers 0-12
326 * -------------------
327 * param area for 3 args to mips_magic_trampoline
328 * -------------------
330 * -------------------
333 mono_arch_create_trampoline_code (MonoTrampolineType tramp_type)
335 guint8 *buf, *tramp, *code = NULL;
337 int max_code_len = 768;
339 /* Now we'll create in 'buf' the MIPS trampoline code. This
340 is the trampoline code common to all methods */
342 code = buf = mono_global_codeman_reserve (max_code_len);
344 /* Allocate the stack frame, and save the return address */
345 mips_addiu (code, mips_sp, mips_sp, -STACK);
346 mips_sw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
348 /* we build the MonoLMF structure on the stack - see mini-mips.h */
349 /* offset of MonoLMF from sp */
350 lmf = STACK - sizeof (MonoLMF) - 8;
352 for (i = 0; i < MONO_MAX_IREGS; i++)
353 mips_sw (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
354 for (i = 0; i < MONO_MAX_FREGS; i++)
355 mips_swc1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
357 /* Set the magic number */
358 mips_load_const (code, mips_at, MIPS_LMF_MAGIC2);
359 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, magic));
361 /* save method info (it was in t8) */
362 mips_sw (code, mips_t8, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, method));
364 /* save frame pointer (caller fp) */
365 mips_sw (code, mips_fp, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, ebp));
367 /* save the IP (caller ip) */
368 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
369 mips_sw (code, mips_zero, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
371 mips_sw (code, mips_ra, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
374 /* jump to mono_get_lmf_addr here */
375 mips_load (code, mips_t9, mono_get_lmf_addr);
376 mips_jalr (code, mips_t9, mips_ra);
379 /* v0 now points at the (MonoLMF **) for the current thread */
381 /* new_lmf->lmf_addr = lmf_addr -- useful when unwinding */
382 mips_sw (code, mips_v0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
384 /* new_lmf->previous_lmf = *lmf_addr */
385 mips_lw (code, mips_at, mips_v0, 0);
386 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
388 /* *(lmf_addr) = new_lmf */
389 mips_addiu (code, mips_at, mips_sp, lmf);
390 mips_sw (code, mips_at, mips_v0, 0);
393 * Now we're ready to call mips_magic_trampoline ().
396 /* Arg 1: stack pointer so that the magic trampoline can access the
397 * registers we saved above
399 mips_move (code, mips_a0, mips_sp);
401 /* Arg 2: code (next address to the instruction that called us) */
402 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
403 mips_move (code, mips_a1, mips_zero);
405 mips_lw (code, mips_a1, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
408 /* Arg 3: MonoMethod *method. */
409 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, method));
411 /* Arg 4: Trampoline */
412 mips_move (code, mips_a3, mips_zero);
414 /* Now go to the trampoline */
415 tramp = (guint8*)mono_get_trampoline_func (tramp_type);
416 mips_load (code, mips_t9, (guint32)tramp);
417 mips_jalr (code, mips_t9, mips_ra);
420 /* Code address is now in v0, move it to at */
421 mips_move (code, mips_at, mips_v0);
424 * Now unwind the MonoLMF
427 /* t0 = current_lmf->previous_lmf */
428 mips_lw (code, mips_t0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
430 mips_lw (code, mips_t1, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
431 /* (*lmf_addr) = previous_lmf */
432 mips_sw (code, mips_t0, mips_t1, 0);
434 /* Restore the callee-saved & argument registers */
435 for (i = 0; i < MONO_MAX_IREGS; i++) {
436 if ((MONO_ARCH_CALLEE_SAVED_REGS | MONO_ARCH_CALLEE_REGS | MIPS_ARG_REGS) & (1 << i))
437 mips_lw (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
439 for (i = 0; i < MONO_MAX_FREGS; i++)
440 mips_lwc1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
442 /* Non-standard function epilogue. Instead of doing a proper
443 * return, we just jump to the compiled code.
445 /* Restore ra & stack pointer, and jump to the code */
447 mips_lw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
448 mips_addiu (code, mips_sp, mips_sp, STACK);
449 if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT)
450 mips_jr (code, mips_ra);
452 mips_jr (code, mips_at);
455 /* Flush instruction cache, since we've generated code */
456 mono_arch_flush_icache (buf, code - buf);
459 g_assert ((code - buf) <= max_code_len);
465 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
467 guint8 *code, *buf, *tramp;
469 tramp = mono_get_trampoline_code (tramp_type);
471 mono_domain_lock (domain);
472 code = buf = mono_code_manager_reserve (domain->code_mp, 32);
473 mono_domain_unlock (domain);
475 /* Prepare the jump to the generic trampoline code
476 * mono_arch_create_trampoline_code() knows we're putting this in t8
478 mips_load (code, mips_t8, arg1);
480 /* Now jump to the generic trampoline code */
481 mips_load (code, mips_at, tramp);
482 mips_jr (code, mips_at);
485 /* Flush instruction cache, since we've generated code */
486 mono_arch_flush_icache (buf, code - buf);
488 g_assert ((code - buf) <= 32);
491 *code_len = code - buf;
497 * This method is only called when running in the Mono Debugger.
500 mono_debugger_create_notification_function (void)
505 ptr = buf = mono_global_codeman_reserve (16);
506 mips_break (buf, 0xd0);
507 mips_jr (buf, mips_ra);
509 mono_arch_flush_icache (ptr, buf - ptr);
518 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 encoded_offset)
520 /* FIXME: implement! */
521 g_assert_not_reached ();
526 mono_arch_get_rgctx_lazy_fetch_offset (gpointer *regs)
528 /* FIXME: implement! */
529 g_assert_not_reached ();