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:
81 On entry, 'code' points just after one of the above sequences.
85 if ((code[-2] >> 26) == 0x03) {
86 //g_print ("direct patching\n");
87 mips_patch ((code-2), (gsize)addr);
89 /* Sanity check: look for the jalr */
90 g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
92 //printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
94 /* The lui / addiu / jalr case */
95 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
96 mips_patch ((code-4), (gsize)addr);
98 g_assert_not_reached ();
104 mono_arch_patch_plt_entry (guint8 *code, guint8 *addr)
106 g_assert_not_reached ();
109 /* Stack size for trampoline function
110 * MIPS_MINIMAL_STACK_SIZE + 16 (args + alignment to mips_magic_trampoline)
111 * + MonoLMF + 14 fp regs + 13 gregs + alignment
112 * #define STACK (MIPS_MINIMAL_STACK_SIZE + 4 * sizeof (gulong) + sizeof (MonoLMF) + 14 * sizeof (double) + 13 * (sizeof (gulong)))
113 * STACK would be 444 for 32 bit darwin
116 #define STACK (4*4 + 8 + sizeof(MonoLMF) + 32)
120 mono_arch_get_vcall_slot (guint8 *code_ptr, gpointer *regs, int *displacement)
126 guint32 *code = (guint32*)code_ptr;
129 /* On MIPS, we are passed sp instead of the register array */
132 //printf ("mips_magic_trampoline: 0x%08x @ 0x%0x\n", *(code-2), code-2);
135 if ((code[-2] >> 26) == 0x03)
138 /* Sanity check: look for the jalr */
139 g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
141 reg = (code[-2] >> 21) & 0x1f;
143 //printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
145 /* The lui / addiu / jalr case */
146 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
150 /* Probably a vtable lookup */
152 /* Walk backwards to find 'lw reg,XX(base)' */
154 guint32 mask = (0x3f << 26) | (0x1f << 16);
155 guint32 match = (0x23 << 26) | (reg << 16);
156 if((*code & mask) == match) {
160 /* lw reg,XX(base) */
161 base = (*code >> 21) & 0x1f;
162 soff = (*code & 0xffff);
167 MonoLMF *lmf = (MonoLMF*)((char *)regs + 12*4);
168 g_assert (lmf->magic == MIPS_LMF_MAGIC2);
169 o = (gpointer)lmf->iregs [base];
177 *displacement = offset;
182 mono_arch_get_vcall_slot_addr (guint8 *code, gpointer *regs)
186 vt = mono_arch_get_vcall_slot (code, regs, &displacement);
189 return (gpointer*)((char*)vt + displacement);
193 mono_arch_nullify_plt_entry (guint8 *code)
195 g_assert_not_reached ();
199 * mips_magic_trampoline:
200 * @code: pointer into caller code
201 * @method: the method to translate
204 * This method is called by the function 'arch_create_jit_trampoline', which in
205 * turn is called by the trampoline functions for virtual methods.
206 * After having called the JIT compiler to compile the method, it inspects the
207 * caller code to find the address of the method-specific part of the
208 * trampoline vtable slot for this method, updates it with a fragment that calls
209 * the newly compiled code and returns this address of the compiled code to
210 * 'arch_create_jit_trampoline'
214 mips_magic_trampoline (MonoMethod *method, guint32 *code, char *sp)
218 MonoJitInfo *ji, *target_ji;
222 addr = mono_compile_method (method);
228 /* We can't trampoline across domains */
229 ji = mono_jit_info_table_find (mono_domain_get (), code);
230 target_ji = mono_jit_info_table_find (mono_domain_get (), addr);
231 if (!mono_method_same_domain (ji, target_ji))
235 g_print ("mips_magic: method code at %p from %p for %s:%s\n",
236 addr, code, method->klass->name, method->name);
238 /* Locate the address of the method-specific trampoline. The call using
239 the vtable slot that took the processing flow to 'arch_create_jit_trampoline'
240 looks something like this:
249 On entry, 'code' points just after one of the above sequences.
253 if ((code[-2] >> 26) == 0x03) {
254 g_print ("direct patching\n");
255 mips_patch ((char*)(code-2), addr);
259 /* Sanity check: look for the jalr */
260 g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
262 reg = (code[-2] >> 21) & 0x1f;
264 //printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
266 /* The lui / addiu / jalr case */
267 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
268 mips_patch ((char*)(code-4), addr);
272 //printf ("mips_magic_trampoline: 0x%08x @ 0x%0x\n", *(code-2), code-2);
274 /* Probably a vtable lookup */
276 /* Walk backwards to find 'lw reg,XX(base)' */
278 guint32 mask = (0x3f << 26) | (0x1f << 16);
279 guint32 match = (0x23 << 26) | (reg << 16);
280 if((*code & mask) == match) {
284 /* lw reg,XX(base) */
285 base = (*code >> 21) & 0x1f;
286 soff = (*code & 0xffff);
290 reg_offset = STACK - sizeof (MonoLMF)
291 + G_STRUCT_OFFSET (MonoLMF, iregs[base]);
292 /* o contains now the value of register reg */
293 vtable = *((char**) (sp + reg_offset));
295 g_print ("patching reg is %d, offset %d (vtable %p) @ %p\n",
296 base, offset, vtable, code);
302 /* this is not done for non-virtual calls, because in that case
303 we won't have an object, but the actual pointer to the
304 valuetype as the this argument
306 if (method->klass->valuetype && !mono_aot_is_got_entry (code, vtable))
307 addr = get_unbox_trampoline (method, addr);
310 if (mono_aot_is_got_entry (code, vtable) || mono_domain_owns_vtable_slot (mono_domain_get (), vtable))
311 *((gpointer *)vtable) = addr;
317 mono_arch_nullify_class_init_trampoline (guint8 *code, gssize *regs)
319 guint32 *code32 = (guint32*)code;
321 /* back up to the jal/jalr instruction */
324 /* Check for jal/jalr -- and NOP it out */
325 if ((((*code32)&0xfc000000) == 0x0c000000)
326 || (((*code32)&0xfc1f003f) == 0x00000009)) {
328 mono_arch_flush_icache ((gpointer)(code32 - 1), 4);
331 g_assert_not_reached ();
336 * Stack frame description when the generic trampoline is called.
338 * --------------------
340 * -------------------
341 * Saved FP registers 0-13
342 * -------------------
343 * Saved general registers 0-12
344 * -------------------
345 * param area for 3 args to mips_magic_trampoline
346 * -------------------
348 * -------------------
351 mono_arch_create_trampoline_code (MonoTrampolineType tramp_type)
353 guint8 *buf, *tramp, *code = NULL;
355 int max_code_len = 768;
357 /* Now we'll create in 'buf' the MIPS trampoline code. This
358 is the trampoline code common to all methods */
360 code = buf = mono_global_codeman_reserve (max_code_len);
362 /* Allocate the stack frame, and save the return address */
363 mips_addiu (code, mips_sp, mips_sp, -STACK);
364 mips_sw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
366 /* we build the MonoLMF structure on the stack - see mini-mips.h */
367 /* offset of MonoLMF from sp */
368 lmf = STACK - sizeof (MonoLMF) - 8;
370 for (i = 0; i < MONO_MAX_IREGS; i++)
371 mips_sw (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
372 for (i = 0; i < MONO_MAX_FREGS; i++)
373 mips_swc1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
375 /* Set the magic number */
376 mips_load_const (code, mips_at, MIPS_LMF_MAGIC2);
377 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, magic));
379 /* save method info (it was in t8) */
380 mips_sw (code, mips_t8, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, method));
382 /* save frame pointer (caller fp) */
383 mips_sw (code, mips_fp, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, ebp));
385 /* save the IP (caller ip) */
386 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
387 mips_sw (code, mips_zero, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
389 mips_sw (code, mips_ra, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
392 /* jump to mono_get_lmf_addr here */
393 mips_load (code, mips_t9, mono_get_lmf_addr);
394 mips_jalr (code, mips_t9, mips_ra);
397 /* v0 now points at the (MonoLMF **) for the current thread */
399 /* new_lmf->lmf_addr = lmf_addr -- useful when unwinding */
400 mips_sw (code, mips_v0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
402 /* new_lmf->previous_lmf = *lmf_addr */
403 mips_lw (code, mips_at, mips_v0, 0);
404 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
406 /* *(lmf_addr) = new_lmf */
407 mips_addiu (code, mips_at, mips_sp, lmf);
408 mips_sw (code, mips_at, mips_v0, 0);
411 * Now we're ready to call mips_magic_trampoline ().
414 /* Arg 1: stack pointer so that the magic trampoline can access the
415 * registers we saved above
417 mips_move (code, mips_a0, mips_sp);
419 /* Arg 2: code (next address to the instruction that called us) */
420 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
421 mips_move (code, mips_a1, mips_zero);
423 mips_lw (code, mips_a1, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
426 /* Arg 3: MonoMethod *method. */
427 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, method));
429 /* Arg 4: Trampoline */
430 mips_move (code, mips_a3, mips_zero);
432 /* Now go to the trampoline */
433 tramp = (guint8*)mono_get_trampoline_func (tramp_type);
434 mips_load (code, mips_t9, (guint32)tramp);
435 mips_jalr (code, mips_t9, mips_ra);
438 /* Code address is now in v0, move it to at */
439 mips_move (code, mips_at, mips_v0);
442 * Now unwind the MonoLMF
445 /* t0 = current_lmf->previous_lmf */
446 mips_lw (code, mips_t0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
448 mips_lw (code, mips_t1, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
449 /* (*lmf_addr) = previous_lmf */
450 mips_sw (code, mips_t0, mips_t1, 0);
452 /* Restore the callee-saved & argument registers */
453 for (i = 0; i < MONO_MAX_IREGS; i++) {
454 if ((MONO_ARCH_CALLEE_SAVED_REGS | MONO_ARCH_CALLEE_REGS | MIPS_ARG_REGS) & (1 << i))
455 mips_lw (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
457 for (i = 0; i < MONO_MAX_FREGS; i++)
458 mips_lwc1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
460 /* Non-standard function epilogue. Instead of doing a proper
461 * return, we just jump to the compiled code.
463 /* Restore ra & stack pointer, and jump to the code */
465 mips_lw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
466 mips_addiu (code, mips_sp, mips_sp, STACK);
467 if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT)
468 mips_jr (code, mips_ra);
470 mips_jr (code, mips_at);
473 /* Flush instruction cache, since we've generated code */
474 mono_arch_flush_icache (buf, code - buf);
477 g_assert ((code - buf) <= max_code_len);
483 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
485 guint8 *code, *buf, *tramp;
487 tramp = mono_get_trampoline_code (tramp_type);
489 mono_domain_lock (domain);
490 code = buf = mono_code_manager_reserve (domain->code_mp, 32);
491 mono_domain_unlock (domain);
493 /* Prepare the jump to the generic trampoline code
494 * mono_arch_create_trampoline_code() knows we're putting this in t8
496 mips_load (code, mips_t8, arg1);
498 /* Now jump to the generic trampoline code */
499 mips_load (code, mips_at, tramp);
500 mips_jr (code, mips_at);
503 /* Flush instruction cache, since we've generated code */
504 mono_arch_flush_icache (buf, code - buf);
506 g_assert ((code - buf) <= 32);
509 *code_len = code - buf;
515 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 encoded_offset)
517 /* FIXME: implement! */
518 g_assert_not_reached ();
523 mono_arch_create_generic_class_init_trampoline (void)
525 /* FIXME: implement! */
526 g_assert_not_reached ();