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:
29 * @gsctx: the generic sharing context
31 * @addr: pointer to native code for @m
33 * when value type methods are called through the vtable we need to unbox the
34 * this argument. This method returns a pointer to a trampoline which does
35 * unboxing before calling the method
38 mono_arch_get_unbox_trampoline (MonoGenericSharingContext *gsctx, MonoMethod *m, gpointer addr)
41 int this_pos = mips_a0;
42 MonoDomain *domain = mono_domain_get ();
44 if (MONO_TYPE_ISSTRUCT (mono_method_signature (m)->ret))
47 mono_domain_lock (domain);
48 start = code = mono_code_manager_reserve (domain->code_mp, 20);
49 mono_domain_unlock (domain);
51 mips_load (code, mips_t9, addr);
52 mips_addiu (code, this_pos, this_pos, sizeof (MonoObject));
53 mips_jr (code, mips_t9);
56 mono_arch_flush_icache (start, code - start);
57 g_assert ((code - start) <= 20);
58 /*g_print ("unbox trampoline at %d for %s:%s\n", this_pos, m->klass->name, m->name);
59 g_print ("unbox code is at %p for method at %p\n", start, addr);*/
65 mono_arch_patch_callsite (guint8 *method_start, guint8 *orig_code, guint8 *addr)
67 guint32 *code = (guint32*)orig_code;
69 /* Locate the address of the method-specific trampoline. The call using
70 the vtable slot that took the processing flow to 'arch_create_jit_trampoline'
71 looks something like this:
80 On entry, 'code' points just after one of the above sequences.
84 if ((code[-2] >> 26) == 0x03) {
85 //g_print ("direct patching\n");
86 mips_patch ((code-2), (gsize)addr);
88 /* Sanity check: look for the jalr */
89 g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
91 //printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
93 /* The lui / addiu / jalr case */
94 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
95 mips_patch ((code-4), (gsize)addr);
97 g_assert_not_reached ();
103 mono_arch_patch_plt_entry (guint8 *code, guint8 *addr)
105 g_assert_not_reached ();
108 /* Stack size for trampoline function
109 * MIPS_MINIMAL_STACK_SIZE + 16 (args + alignment to mips_magic_trampoline)
110 * + MonoLMF + 14 fp regs + 13 gregs + alignment
111 * #define STACK (MIPS_MINIMAL_STACK_SIZE + 4 * sizeof (gulong) + sizeof (MonoLMF) + 14 * sizeof (double) + 13 * (sizeof (gulong)))
112 * STACK would be 444 for 32 bit darwin
115 #define STACK (4*4 + 8 + sizeof(MonoLMF) + 32)
118 mono_arch_get_vcall_slot_addr (guint8* code8, gpointer *regs)
123 guint32 *code = (guint32*)code8;
126 /* On MIPS, we are passed sp instead of the register array */
129 //printf ("mips_magic_trampoline: 0x%08x @ 0x%0x\n", *(code-2), code-2);
132 if ((code[-2] >> 26) == 0x03)
135 /* Sanity check: look for the jalr */
136 g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
138 reg = (code[-2] >> 21) & 0x1f;
140 //printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
142 /* The lui / addiu / jalr case */
143 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
147 /* Probably a vtable lookup */
149 /* Walk backwards to find 'lw reg,XX(base)' */
151 guint32 mask = (0x3f << 26) | (0x1f << 16);
152 guint32 match = (0x23 << 26) | (reg << 16);
153 if((*code & mask) == match) {
157 /* lw reg,XX(base) */
158 base = (*code >> 21) & 0x1f;
159 soff = (*code & 0xffff);
163 reg_offset = STACK - sizeof (MonoLMF)
164 + G_STRUCT_OFFSET (MonoLMF, iregs[base]);
165 /* o contains now the value of register reg */
166 vtable = *((char**) (sp + reg_offset));
167 return (gpointer*)vtable;
171 g_assert_not_reached ();
176 mono_arch_nullify_plt_entry (guint8 *code)
178 g_assert_not_reached ();
182 * mips_magic_trampoline:
183 * @code: pointer into caller code
184 * @method: the method to translate
187 * This method is called by the function 'arch_create_jit_trampoline', which in
188 * turn is called by the trampoline functions for virtual methods.
189 * After having called the JIT compiler to compile the method, it inspects the
190 * caller code to find the address of the method-specific part of the
191 * trampoline vtable slot for this method, updates it with a fragment that calls
192 * the newly compiled code and returns this address of the compiled code to
193 * 'arch_create_jit_trampoline'
197 mips_magic_trampoline (MonoMethod *method, guint32 *code, char *sp)
201 MonoJitInfo *ji, *target_ji;
205 addr = mono_compile_method (method);
211 /* We can't trampoline across domains */
212 ji = mono_jit_info_table_find (mono_domain_get (), code);
213 target_ji = mono_jit_info_table_find (mono_domain_get (), addr);
214 if (!mono_method_same_domain (ji, target_ji))
218 g_print ("mips_magic: method code at %p from %p for %s:%s\n",
219 addr, code, method->klass->name, method->name);
221 /* Locate the address of the method-specific trampoline. The call using
222 the vtable slot that took the processing flow to 'arch_create_jit_trampoline'
223 looks something like this:
232 On entry, 'code' points just after one of the above sequences.
236 if ((code[-2] >> 26) == 0x03) {
237 g_print ("direct patching\n");
238 mips_patch ((char*)(code-2), addr);
242 /* Sanity check: look for the jalr */
243 g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
245 reg = (code[-2] >> 21) & 0x1f;
247 //printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
249 /* The lui / addiu / jalr case */
250 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
251 mips_patch ((char*)(code-4), addr);
255 //printf ("mips_magic_trampoline: 0x%08x @ 0x%0x\n", *(code-2), code-2);
257 /* Probably a vtable lookup */
259 /* Walk backwards to find 'lw reg,XX(base)' */
261 guint32 mask = (0x3f << 26) | (0x1f << 16);
262 guint32 match = (0x23 << 26) | (reg << 16);
263 if((*code & mask) == match) {
267 /* lw reg,XX(base) */
268 base = (*code >> 21) & 0x1f;
269 soff = (*code & 0xffff);
273 reg_offset = STACK - sizeof (MonoLMF)
274 + G_STRUCT_OFFSET (MonoLMF, iregs[base]);
275 /* o contains now the value of register reg */
276 vtable = *((char**) (sp + reg_offset));
278 g_print ("patching reg is %d, offset %d (vtable %p) @ %p\n",
279 base, offset, vtable, code);
285 /* this is not done for non-virtual calls, because in that case
286 we won't have an object, but the actual pointer to the
287 valuetype as the this argument
289 if (method->klass->valuetype && !mono_aot_is_got_entry (code, vtable))
290 addr = get_unbox_trampoline (method, addr);
293 if (mono_aot_is_got_entry (code, vtable) || mono_domain_owns_vtable_slot (mono_domain_get (), vtable))
294 *((gpointer *)vtable) = addr;
300 mono_arch_nullify_class_init_trampoline (guint8 *code, gssize *regs)
302 guint32 *code32 = (guint32*)code;
304 /* back up to the jal/jalr instruction */
307 /* Check for jal/jalr -- and NOP it out */
308 if ((((*code32)&0xfc000000) == 0x0c000000)
309 || (((*code32)&0xfc1f003f) == 0x00000009)) {
311 mono_arch_flush_icache ((gpointer)(code32 - 1), 4);
314 g_assert_not_reached ();
319 * Stack frame description when the generic trampoline is called.
321 * --------------------
323 * -------------------
324 * Saved FP registers 0-13
325 * -------------------
326 * Saved general registers 0-12
327 * -------------------
328 * param area for 3 args to mips_magic_trampoline
329 * -------------------
331 * -------------------
334 mono_arch_create_trampoline_code (MonoTrampolineType tramp_type)
336 guint8 *buf, *tramp, *code = NULL;
338 int max_code_len = 768;
340 /* Now we'll create in 'buf' the MIPS trampoline code. This
341 is the trampoline code common to all methods */
343 code = buf = mono_global_codeman_reserve (max_code_len);
345 /* Allocate the stack frame, and save the return address */
346 mips_addiu (code, mips_sp, mips_sp, -STACK);
347 mips_sw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
349 /* we build the MonoLMF structure on the stack - see mini-mips.h */
350 /* offset of MonoLMF from sp */
351 lmf = STACK - sizeof (MonoLMF) - 8;
353 for (i = 0; i < MONO_MAX_IREGS; i++)
354 mips_sw (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
355 for (i = 0; i < MONO_MAX_FREGS; i++)
356 mips_swc1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
358 /* Set the magic number */
359 mips_load_const (code, mips_at, MIPS_LMF_MAGIC2);
360 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, magic));
362 /* save method info (it was in t8) */
363 mips_sw (code, mips_t8, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, method));
365 /* save frame pointer (caller fp) */
366 mips_sw (code, mips_fp, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, ebp));
368 /* save the IP (caller ip) */
369 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
370 mips_sw (code, mips_zero, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
372 mips_sw (code, mips_ra, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
375 /* jump to mono_get_lmf_addr here */
376 mips_load (code, mips_t9, mono_get_lmf_addr);
377 mips_jalr (code, mips_t9, mips_ra);
380 /* v0 now points at the (MonoLMF **) for the current thread */
382 /* new_lmf->lmf_addr = lmf_addr -- useful when unwinding */
383 mips_sw (code, mips_v0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
385 /* new_lmf->previous_lmf = *lmf_addr */
386 mips_lw (code, mips_at, mips_v0, 0);
387 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
389 /* *(lmf_addr) = new_lmf */
390 mips_addiu (code, mips_at, mips_sp, lmf);
391 mips_sw (code, mips_at, mips_v0, 0);
394 * Now we're ready to call mips_magic_trampoline ().
397 /* Arg 1: stack pointer so that the magic trampoline can access the
398 * registers we saved above
400 mips_move (code, mips_a0, mips_sp);
402 /* Arg 2: code (next address to the instruction that called us) */
403 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
404 mips_move (code, mips_a1, mips_zero);
406 mips_lw (code, mips_a1, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
409 /* Arg 3: MonoMethod *method. */
410 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, method));
412 /* Arg 4: Trampoline */
413 mips_move (code, mips_a3, mips_zero);
415 /* Now go to the trampoline */
416 tramp = (guint8*)mono_get_trampoline_func (tramp_type);
417 mips_load (code, mips_t9, (guint32)tramp);
418 mips_jalr (code, mips_t9, mips_ra);
421 /* Code address is now in v0, move it to at */
422 mips_move (code, mips_at, mips_v0);
425 * Now unwind the MonoLMF
428 /* t0 = current_lmf->previous_lmf */
429 mips_lw (code, mips_t0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
431 mips_lw (code, mips_t1, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
432 /* (*lmf_addr) = previous_lmf */
433 mips_sw (code, mips_t0, mips_t1, 0);
435 /* Restore the callee-saved & argument registers */
436 for (i = 0; i < MONO_MAX_IREGS; i++) {
437 if ((MONO_ARCH_CALLEE_SAVED_REGS | MONO_ARCH_CALLEE_REGS | MIPS_ARG_REGS) & (1 << i))
438 mips_lw (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
440 for (i = 0; i < MONO_MAX_FREGS; i++)
441 mips_lwc1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
443 /* Non-standard function epilogue. Instead of doing a proper
444 * return, we just jump to the compiled code.
446 /* Restore ra & stack pointer, and jump to the code */
448 mips_lw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
449 mips_addiu (code, mips_sp, mips_sp, STACK);
450 if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT)
451 mips_jr (code, mips_ra);
453 mips_jr (code, mips_at);
456 /* Flush instruction cache, since we've generated code */
457 mono_arch_flush_icache (buf, code - buf);
460 g_assert ((code - buf) <= max_code_len);
466 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
468 guint8 *code, *buf, *tramp;
470 tramp = mono_get_trampoline_code (tramp_type);
472 mono_domain_lock (domain);
473 code = buf = mono_code_manager_reserve (domain->code_mp, 32);
474 mono_domain_unlock (domain);
476 /* Prepare the jump to the generic trampoline code
477 * mono_arch_create_trampoline_code() knows we're putting this in t8
479 mips_load (code, mips_t8, arg1);
481 /* Now jump to the generic trampoline code */
482 mips_load (code, mips_at, tramp);
483 mips_jr (code, mips_at);
486 /* Flush instruction cache, since we've generated code */
487 mono_arch_flush_icache (buf, code - buf);
489 g_assert ((code - buf) <= 32);
492 *code_len = code - buf;
498 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 encoded_offset)
500 /* FIXME: implement! */
501 g_assert_not_reached ();
506 mono_arch_get_rgctx_lazy_fetch_offset (gpointer *regs)
508 /* FIXME: implement! */
509 g_assert_not_reached ();