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 start = code = mono_domain_code_reserve (domain, 20);
49 mips_load (code, mips_t9, addr);
50 mips_addiu (code, this_pos, this_pos, sizeof (MonoObject));
51 mips_jr (code, mips_t9);
54 mono_arch_flush_icache (start, code - start);
55 g_assert ((code - start) <= 20);
56 /*g_print ("unbox trampoline at %d for %s:%s\n", this_pos, m->klass->name, m->name);
57 g_print ("unbox code is at %p for method at %p\n", start, addr);*/
63 mono_arch_patch_callsite (guint8 *method_start, guint8 *orig_code, guint8 *addr)
65 guint32 *code = (guint32*)orig_code;
67 /* Locate the address of the method-specific trampoline. The call using
68 the vtable slot that took the processing flow to 'arch_create_jit_trampoline'
69 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, gpointer *got, mgreg_t *regs, 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*IREG_SIZE + 8 + sizeof(MonoLMF) + 32)
118 mono_arch_get_vcall_slot (guint8 *code_ptr, mgreg_t *regs, int *displacement)
124 guint32 *code = (guint32*)code_ptr;
127 /* On MIPS, we are passed sp instead of the register array */
130 //printf ("mips_magic_trampoline: 0x%08x @ 0x%0x\n", *(code-2), code-2);
133 if ((code[-2] >> 26) == 0x03)
136 /* Sanity check: look for the jalr */
137 g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
139 reg = (code[-2] >> 21) & 0x1f;
141 //printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
143 /* The lui / addiu / jalr case */
144 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
148 /* Probably a vtable lookup */
150 /* Walk backwards to find 'lw reg,XX(base)' */
152 guint32 mask = (0x3f << 26) | (0x1f << 16);
153 guint32 match = (0x23 << 26) | (reg << 16);
154 if((*code & mask) == match) {
158 /* lw reg,XX(base) */
159 base = (*code >> 21) & 0x1f;
160 soff = (*code & 0xffff);
165 MonoLMF *lmf = (MonoLMF*)((char *)regs + 12*IREG_SIZE);
166 g_assert (lmf->magic == MIPS_LMF_MAGIC2);
167 o = (gpointer)lmf->iregs [base];
175 *displacement = offset;
180 mono_arch_nullify_plt_entry (guint8 *code, mgreg_t *regs)
182 g_assert_not_reached ();
186 mono_arch_nullify_class_init_trampoline (guint8 *code, mgreg_t *regs)
188 guint32 *code32 = (guint32*)code;
190 /* back up to the jal/jalr instruction */
193 /* Check for jal/jalr -- and NOP it out */
194 if ((((*code32)&0xfc000000) == 0x0c000000)
195 || (((*code32)&0xfc1f003f) == 0x00000009)) {
197 mono_arch_flush_icache ((gpointer)(code32 - 1), 4);
200 g_assert_not_reached ();
205 * Stack frame description when the generic trampoline is called.
207 * --------------------
209 * -------------------
210 * Saved FP registers 0-13
211 * -------------------
212 * Saved general registers 0-12
213 * -------------------
214 * param area for 3 args to mips_magic_trampoline
215 * -------------------
217 * -------------------
220 mono_arch_create_trampoline_code (MonoTrampolineType tramp_type)
222 guint8 *buf, *tramp, *code = NULL;
224 int max_code_len = 768;
226 /* Now we'll create in 'buf' the MIPS trampoline code. This
227 is the trampoline code common to all methods */
229 code = buf = mono_global_codeman_reserve (max_code_len);
231 /* Allocate the stack frame, and save the return address */
232 mips_addiu (code, mips_sp, mips_sp, -STACK);
233 mips_sw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
235 /* we build the MonoLMF structure on the stack - see mini-mips.h */
236 /* offset of MonoLMF from sp */
237 lmf = STACK - sizeof (MonoLMF) - 8;
239 for (i = 0; i < MONO_MAX_IREGS; i++)
240 MIPS_SW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
241 for (i = 0; i < MONO_MAX_FREGS; i++)
242 MIPS_SWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
244 /* Set the magic number */
245 mips_load_const (code, mips_at, MIPS_LMF_MAGIC2);
246 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, magic));
248 /* save method info (it was in t8) */
249 mips_sw (code, mips_t8, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, method));
251 /* save frame pointer (caller fp) */
252 MIPS_SW (code, mips_fp, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, ebp));
254 /* save the IP (caller ip) */
255 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
256 mips_sw (code, mips_zero, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
258 mips_sw (code, mips_ra, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
261 /* jump to mono_get_lmf_addr here */
262 mips_load (code, mips_t9, mono_get_lmf_addr);
263 mips_jalr (code, mips_t9, mips_ra);
266 /* v0 now points at the (MonoLMF **) for the current thread */
268 /* new_lmf->lmf_addr = lmf_addr -- useful when unwinding */
269 mips_sw (code, mips_v0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
271 /* new_lmf->previous_lmf = *lmf_addr */
272 mips_lw (code, mips_at, mips_v0, 0);
273 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
275 /* *(lmf_addr) = new_lmf */
276 mips_addiu (code, mips_at, mips_sp, lmf);
277 mips_sw (code, mips_at, mips_v0, 0);
280 * Now we're ready to call mips_magic_trampoline ().
283 /* Arg 1: stack pointer so that the magic trampoline can access the
284 * registers we saved above
286 mips_move (code, mips_a0, mips_sp);
288 /* Arg 2: code (next address to the instruction that called us) */
289 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
290 mips_move (code, mips_a1, mips_zero);
292 mips_lw (code, mips_a1, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
295 /* Arg 3: MonoMethod *method. */
296 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, method));
298 /* Arg 4: Trampoline */
299 mips_move (code, mips_a3, mips_zero);
301 /* Now go to the trampoline */
302 tramp = (guint8*)mono_get_trampoline_func (tramp_type);
303 mips_load (code, mips_t9, (guint32)tramp);
304 mips_jalr (code, mips_t9, mips_ra);
307 /* Code address is now in v0, move it to at */
308 mips_move (code, mips_at, mips_v0);
311 * Now unwind the MonoLMF
314 /* t0 = current_lmf->previous_lmf */
315 mips_lw (code, mips_t0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
317 mips_lw (code, mips_t1, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
318 /* (*lmf_addr) = previous_lmf */
319 mips_sw (code, mips_t0, mips_t1, 0);
321 /* Restore the callee-saved & argument registers */
322 for (i = 0; i < MONO_MAX_IREGS; i++) {
323 if ((MONO_ARCH_CALLEE_SAVED_REGS | MONO_ARCH_CALLEE_REGS | MIPS_ARG_REGS) & (1 << i))
324 MIPS_LW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
326 for (i = 0; i < MONO_MAX_FREGS; i++)
327 MIPS_LWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
329 /* Non-standard function epilogue. Instead of doing a proper
330 * return, we just jump to the compiled code.
332 /* Restore ra & stack pointer, and jump to the code */
334 mips_lw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
335 mips_addiu (code, mips_sp, mips_sp, STACK);
336 if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT)
337 mips_jr (code, mips_ra);
339 mips_jr (code, mips_at);
342 /* Flush instruction cache, since we've generated code */
343 mono_arch_flush_icache (buf, code - buf);
346 g_assert ((code - buf) <= max_code_len);
352 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
354 guint8 *code, *buf, *tramp;
356 tramp = mono_get_trampoline_code (tramp_type);
358 code = buf = mono_domain_code_reserve (domain, 32);
360 /* Prepare the jump to the generic trampoline code
361 * mono_arch_create_trampoline_code() knows we're putting this in t8
363 mips_load (code, mips_t8, arg1);
365 /* Now jump to the generic trampoline code */
366 mips_load (code, mips_at, tramp);
367 mips_jr (code, mips_at);
370 /* Flush instruction cache, since we've generated code */
371 mono_arch_flush_icache (buf, code - buf);
373 g_assert ((code - buf) <= 32);
376 *code_len = code - buf;
382 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 encoded_offset)
384 /* FIXME: implement! */
385 g_assert_not_reached ();
390 mono_arch_create_generic_class_init_trampoline (void)
392 /* FIXME: implement! */
393 g_assert_not_reached ();