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"
27 static guint8* nullified_class_init_trampoline;
30 * get_unbox_trampoline:
31 * @gsctx: the generic sharing context
33 * @addr: pointer to native code for @m
35 * when value type methods are called through the vtable we need to unbox the
36 * this argument. This method returns a pointer to a trampoline which does
37 * unboxing before calling the method
40 mono_arch_get_unbox_trampoline (MonoGenericSharingContext *gsctx, MonoMethod *m, gpointer addr)
43 int this_pos = mips_a0;
44 MonoDomain *domain = mono_domain_get ();
46 if (MONO_TYPE_ISSTRUCT (mono_method_signature (m)->ret))
49 start = code = mono_domain_code_reserve (domain, 20);
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.
70 The call using the vtable slot that took the processing flow to
71 'arch_create_jit_trampoline' looks something like one of these:
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);
90 /* Look for the jalr */
91 if ((code[-2] & 0xfc1f003f) == 0x00000009) {
92 /* The lui / addiu / jalr case */
93 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09
94 && (code [-2] >> 26) == 0) {
95 mips_patch ((code-4), (gsize)addr);
99 g_print("error: bad patch at 0x%08x\n", code);
100 g_assert_not_reached ();
104 mono_arch_patch_plt_entry (guint8 *code, gpointer *got, mgreg_t *regs, 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*IREG_SIZE + 8 + sizeof(MonoLMF) + 32)
120 mono_arch_get_vcall_slot (guint8 *code_ptr, mgreg_t *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*IREG_SIZE);
168 g_assert (lmf->magic == MIPS_LMF_MAGIC2);
169 o = (gpointer)lmf->iregs [base];
172 o = (gpointer) regs [base];
177 *displacement = offset;
182 mono_arch_nullify_plt_entry (guint8 *code, mgreg_t *regs)
184 if (mono_aot_only && !nullified_class_init_trampoline)
185 nullified_class_init_trampoline = mono_aot_get_trampoline ("nullified_class_init_trampoline");
187 mono_arch_patch_plt_entry (code, NULL, regs, nullified_class_init_trampoline);
191 mono_arch_nullify_class_init_trampoline (guint8 *code, mgreg_t *regs)
193 guint32 *code32 = (guint32*)code;
195 /* back up to the jal/jalr instruction */
198 /* Check for jal/jalr -- and NOP it out */
199 if ((((*code32)&0xfc000000) == 0x0c000000)
200 || (((*code32)&0xfc1f003f) == 0x00000009)) {
202 mono_arch_flush_icache ((gpointer)(code32 - 1), 4);
205 g_assert_not_reached ();
209 mono_arch_get_nullified_class_init_trampoline (MonoTrampInfo **info)
213 code = buf = mono_global_codeman_reserve (16);
215 mips_jr (code, mips_ra);
218 mono_arch_flush_icache (buf, code - buf);
221 *info = mono_tramp_info_create (g_strdup_printf ("nullified_class_init_trampoline"), buf, code - buf, NULL, NULL);
227 * Stack frame description when the generic trampoline is called.
229 * --------------------
231 * -------------------
232 * Saved FP registers 0-13
233 * -------------------
234 * Saved general registers 0-12
235 * -------------------
236 * param area for 3 args to mips_magic_trampoline
237 * -------------------
239 * -------------------
242 mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
244 guint8 *buf, *tramp, *code = NULL;
246 GSList *unwind_ops = NULL;
247 MonoJumpInfo *ji = NULL;
248 int max_code_len = 768;
250 /* AOT not supported on MIPS yet */
253 /* Now we'll create in 'buf' the MIPS trampoline code. This
254 is the trampoline code common to all methods */
256 code = buf = mono_global_codeman_reserve (max_code_len);
258 /* Allocate the stack frame, and save the return address */
259 mips_addiu (code, mips_sp, mips_sp, -STACK);
260 mips_sw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
262 /* we build the MonoLMF structure on the stack - see mini-mips.h */
263 /* offset of MonoLMF from sp */
264 lmf = STACK - sizeof (MonoLMF) - 8;
266 for (i = 0; i < MONO_MAX_IREGS; i++)
267 MIPS_SW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
268 for (i = 0; i < MONO_MAX_FREGS; i++)
269 MIPS_SWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
271 /* Set the magic number */
272 mips_load_const (code, mips_at, MIPS_LMF_MAGIC2);
273 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, magic));
275 /* save method info (it was in t8) */
276 mips_sw (code, mips_t8, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, method));
278 /* save frame pointer (caller fp) */
279 MIPS_SW (code, mips_fp, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, ebp));
281 /* save the IP (caller ip) */
282 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
283 mips_sw (code, mips_zero, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
285 mips_sw (code, mips_ra, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
288 /* jump to mono_get_lmf_addr here */
289 mips_load (code, mips_t9, mono_get_lmf_addr);
290 mips_jalr (code, mips_t9, mips_ra);
293 /* v0 now points at the (MonoLMF **) for the current thread */
295 /* new_lmf->lmf_addr = lmf_addr -- useful when unwinding */
296 mips_sw (code, mips_v0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
298 /* new_lmf->previous_lmf = *lmf_addr */
299 mips_lw (code, mips_at, mips_v0, 0);
300 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
302 /* *(lmf_addr) = new_lmf */
303 mips_addiu (code, mips_at, mips_sp, lmf);
304 mips_sw (code, mips_at, mips_v0, 0);
307 * Now we're ready to call mips_magic_trampoline ().
310 /* Arg 1: pointer to registers so that the magic trampoline can
311 * access what we saved above
313 mips_addiu (code, mips_a0, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[0]));
315 /* Arg 2: code (next address to the instruction that called us) */
316 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
317 mips_move (code, mips_a1, mips_zero);
319 mips_lw (code, mips_a1, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
322 /* Arg 3: MonoMethod *method. */
323 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, method));
325 /* Arg 4: Trampoline */
326 mips_move (code, mips_a3, mips_zero);
328 /* Now go to the trampoline */
329 tramp = (guint8*)mono_get_trampoline_func (tramp_type);
330 mips_load (code, mips_t9, (guint32)tramp);
331 mips_jalr (code, mips_t9, mips_ra);
334 /* Code address is now in v0, move it to at */
335 mips_move (code, mips_at, mips_v0);
338 * Now unwind the MonoLMF
341 /* t0 = current_lmf->previous_lmf */
342 mips_lw (code, mips_t0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
344 mips_lw (code, mips_t1, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
345 /* (*lmf_addr) = previous_lmf */
346 mips_sw (code, mips_t0, mips_t1, 0);
348 /* Restore the callee-saved & argument registers */
349 for (i = 0; i < MONO_MAX_IREGS; i++) {
350 if ((MONO_ARCH_CALLEE_SAVED_REGS | MONO_ARCH_CALLEE_REGS | MIPS_ARG_REGS) & (1 << i))
351 MIPS_LW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
353 for (i = 0; i < MONO_MAX_FREGS; i++)
354 MIPS_LWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
356 /* Non-standard function epilogue. Instead of doing a proper
357 * return, we just jump to the compiled code.
359 /* Restore ra & stack pointer, and jump to the code */
361 mips_lw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
362 mips_addiu (code, mips_sp, mips_sp, STACK);
363 if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT)
364 mips_jr (code, mips_ra);
366 mips_jr (code, mips_at);
369 /* Flush instruction cache, since we've generated code */
370 mono_arch_flush_icache (buf, code - buf);
373 g_assert ((code - buf) <= max_code_len);
375 if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT)
376 /* Initialize the nullified class init trampoline used in the AOT case */
377 nullified_class_init_trampoline = mono_arch_get_nullified_class_init_trampoline (NULL);
380 *info = mono_tramp_info_create (mono_get_generic_trampoline_name (tramp_type), buf, code - buf, ji, unwind_ops);
386 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
388 guint8 *code, *buf, *tramp;
390 tramp = mono_get_trampoline_code (tramp_type);
392 code = buf = mono_domain_code_reserve (domain, 32);
394 /* Prepare the jump to the generic trampoline code
395 * mono_arch_create_trampoline_code() knows we're putting this in t8
397 mips_load (code, mips_t8, arg1);
399 /* Now jump to the generic trampoline code */
400 mips_load (code, mips_at, tramp);
401 mips_jr (code, mips_at);
404 /* Flush instruction cache, since we've generated code */
405 mono_arch_flush_icache (buf, code - buf);
407 g_assert ((code - buf) <= 32);
410 *code_len = code - buf;
416 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
418 /* FIXME: implement! */
419 g_assert_not_reached ();
424 mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
426 /* FIXME: implement! */
427 g_assert_not_reached ();