X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=blobdiff_plain;f=mono%2Fmini%2Ftramp-mips.c;h=e90e0a3121bfe39db750792f3c8c235d5be678f0;hb=32455dbbe90d3f7826a2bae5a95360e050f04172;hp=9598e49c81a5399ff775ddc22cd526e7250c9024;hpb=b55650eeca69d0ea651c961cbc207a097d94a826;p=mono.git

diff --git a/mono/mini/tramp-mips.c b/mono/mini/tramp-mips.c
index 9598e49c81a..e90e0a3121b 100644
--- a/mono/mini/tramp-mips.c
+++ b/mono/mini/tramp-mips.c
@@ -24,6 +24,8 @@
 #include "mini.h"
 #include "mini-mips.h"
 
+static guint8* nullified_class_init_trampoline;
+
 /*
  * get_unbox_trampoline:
  * @m: method pointer
@@ -33,22 +35,17 @@
  * this argument. This method returns a pointer to a trampoline which does
  * unboxing before calling the method
  */
-static gpointer
-get_unbox_trampoline (MonoMethod *m, gpointer addr)
+gpointer
+mono_arch_get_unbox_trampoline (MonoMethod *m, gpointer addr)
 {
 	guint8 *code, *start;
-	int this_pos = mips_a0;
 	MonoDomain *domain = mono_domain_get ();
-
-	if (!mono_method_signature (m)->ret->byref && MONO_TYPE_ISSTRUCT (mono_method_signature (m)->ret))
-		this_pos = mips_a1;
 	    
-	mono_domain_lock (domain);
-	start = code = mono_code_manager_reserve (domain->code_mp, 20);
-	mono_domain_unlock (domain);
+	start = code = mono_domain_code_reserve (domain, 20);
 
 	mips_load (code, mips_t9, addr);
-	mips_addiu (code, this_pos, this_pos, sizeof (MonoObject));
+	/* The this pointer is kept in a0 */
+	mips_addiu (code, mips_a0, mips_a0, sizeof (MonoObject));
 	mips_jr (code, mips_t9);
 	mips_nop (code);
 
@@ -60,66 +57,17 @@ get_unbox_trampoline (MonoMethod *m, gpointer addr)
 	return start;
 }
 
-/* Stack size for trampoline function 
- * MIPS_MINIMAL_STACK_SIZE + 16 (args + alignment to mips_magic_trampoline)
- * + MonoLMF + 14 fp regs + 13 gregs + alignment
- * #define STACK (MIPS_MINIMAL_STACK_SIZE + 4 * sizeof (gulong) + sizeof (MonoLMF) + 14 * sizeof (double) + 13 * (sizeof (gulong)))
- * STACK would be 444 for 32 bit darwin
- */
-
-#define STACK (4*4 + 8 + sizeof(MonoLMF) + 32)
-
-
-/* Method-specific trampoline code fragment size */
-#define METHOD_TRAMPOLINE_SIZE 64
-
-/* Jump-specific trampoline code fragment size */
-#define JUMP_TRAMPOLINE_SIZE   64
-
-/**
- * mips_magic_trampoline:
- * @code: pointer into caller code
- * @method: the method to translate
- * @sp: stack pointer
- *
- * This method is called by the function 'arch_create_jit_trampoline', which in
- * turn is called by the trampoline functions for virtual methods.
- * After having called the JIT compiler to compile the method, it inspects the
- * caller code to find the address of the method-specific part of the
- * trampoline vtable slot for this method, updates it with a fragment that calls
- * the newly compiled code and returns this address of the compiled code to
- * 'arch_create_jit_trampoline' 
- */
-static gpointer
-mips_magic_trampoline (MonoMethod *method, guint32 *code, char *sp)
+void
+mono_arch_patch_callsite (guint8 *method_start, guint8 *orig_code, guint8 *addr)
 {
-	char *vtable = NULL;
-	gpointer addr;
-        MonoJitInfo *ji, *target_ji;
-	int reg, offset = 0;
-	guint32 base = 0;
-
-	addr = mono_compile_method (method);
-	g_assert (addr);
-
-	if (!code)
-		return addr;
-
-	/* We can't trampoline across domains */
-	ji = mono_jit_info_table_find (mono_domain_get (), code);
-	target_ji = mono_jit_info_table_find (mono_domain_get (), addr);
-	if (!mono_method_same_domain (ji, target_ji))
-		return addr;
-
-#if 0
-	g_print ("mips_magic: method code at %p from %p for %s:%s\n",
-		 addr, code, method->klass->name, method->name);
-#endif
-	/* Locate the address of the method-specific trampoline. The call using
-	the vtable slot that took the processing flow to 'arch_create_jit_trampoline' 
-	looks something like this:
+	guint32 *code = (guint32*)orig_code;
+
+	/* Locate the address of the method-specific trampoline.
+	The call using the vtable slot that took the processing flow to
+	'arch_create_jit_trampoline' looks something like one of these:
 
 		jal	XXXXYYYY
+		nop
 
 		lui	t9, XXXX
 		addiu	t9, YYYY
@@ -131,86 +79,83 @@ mips_magic_trampoline (MonoMethod *method, guint32 *code, char *sp)
 	
 	/* The jal case */
 	if ((code[-2] >> 26) == 0x03) {
-		g_print ("direct patching\n");
-		mips_patch ((char*)(code-2), addr);
-		return addr;
+		//g_print ("direct patching\n");
+		mips_patch ((code-2), (gsize)addr);
+		return;
 	}
-	
-	/* Sanity check: look for the jalr */
-	g_assert((code[-2] & 0xfc1f003f) == 0x00000009);
+	/* Look for the jalr */
+	if ((code[-2] & 0xfc1f003f) == 0x00000009) {
+		/* The lui / addiu / jalr case */
+		if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09
+		    && (code [-2] >> 26) == 0) {
+			mips_patch ((code-4), (gsize)addr);
+			return;
+		}
+	}
+	g_print("error: bad patch at 0x%08x\n", code);
+	g_assert_not_reached ();
+}
 
-	reg = (code[-2] >> 21) & 0x1f;
+void
+mono_arch_patch_plt_entry (guint8 *code, gpointer *got, mgreg_t *regs, guint8 *addr)
+{
+	g_assert_not_reached ();
+}
 
-	//printf ("mips_magic_trampoline: jalr @ 0x%0x, w/ reg %d\n", code-2, reg);
+/* Stack size for trampoline function 
+ * MIPS_MINIMAL_STACK_SIZE + 16 (args + alignment to mips_magic_trampoline)
+ * + MonoLMF + 14 fp regs + 13 gregs + alignment
+ * #define STACK (MIPS_MINIMAL_STACK_SIZE + 4 * sizeof (gulong) + sizeof (MonoLMF) + 14 * sizeof (double) + 13 * (sizeof (gulong)))
+ * STACK would be 444 for 32 bit darwin
+ */
 
-	/* The lui / addiu / jalr case */
-	if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09 && (code [-2] >> 26) == 0) {
-		mips_patch ((char*)(code-4), addr);
-		return addr;
-	}
+#define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
 
-	//printf ("mips_magic_trampoline: 0x%08x @ 0x%0x\n", *(code-2), code-2);
-
-	/* Probably a vtable lookup */
-
-	/* Walk backwards to find 'lw reg,XX(base)' */
-	for(; --code;) {
-		guint32 mask = (0x3f << 26) | (0x1f << 16);
-		guint32 match = (0x23 << 26) | (reg << 16);
-		if((*code & mask) == match) {
-			gint16 soff;
-			gint reg_offset;
-
-			/* lw reg,XX(base) */
-			base = (*code >> 21) & 0x1f;
-			soff = (*code & 0xffff);
-			if (soff & 0x8000)
-				soff |= 0xffff0000;
-			offset = soff;
-			reg_offset = STACK - sizeof (MonoLMF)
-				+ G_STRUCT_OFFSET (MonoLMF, iregs[base]);
-			/* o contains now the value of register reg */
-			vtable = *((char**) (sp + reg_offset));
-#if 0
-			g_print ("patching reg is %d, offset %d (vtable %p) @ %p\n",
-				 base, offset, vtable, code);
-#endif
-			break;
-		}
-	}
+#define STACK (int)(ALIGN_TO(4*IREG_SIZE + 8 + sizeof(MonoLMF) + 32, 8))
 
-	/* this is not done for non-virtual calls, because in that case
-	   we won't have an object, but the actual pointer to the 
-	   valuetype as the this argument
-	 */
-	if (method->klass->valuetype && !mono_aot_is_got_entry (code, vtable))
-		addr = get_unbox_trampoline (method, addr);
+void
+mono_arch_nullify_plt_entry (guint8 *code, mgreg_t *regs)
+{
+	if (mono_aot_only && !nullified_class_init_trampoline)
+		nullified_class_init_trampoline = mono_aot_get_trampoline ("nullified_class_init_trampoline");
 
-	vtable += offset;
-	if (mono_aot_is_got_entry (code, vtable) || mono_domain_owns_vtable_slot (mono_domain_get (), vtable))
-		*((gpointer *)vtable) = addr;
-	return addr;
+	mono_arch_patch_plt_entry (code, NULL, regs, nullified_class_init_trampoline);
 }
 
-static void
-mips_class_init_trampoline (void *vtable, guint32 *code, char *sp)
+void
+mono_arch_nullify_class_init_trampoline (guint8 *code, mgreg_t *regs)
 {
-	//g_print ("mips_class_init: vtable=%p code=%p sp=%p\n", vtable, code, sp);
-
-	mono_runtime_class_init (vtable);
+	guint32 *code32 = (guint32*)code;
 
 	/* back up to the jal/jalr instruction */
-	code -= 2;
+	code32 -= 2;
 
 	/* Check for jal/jalr -- and NOP it out */
-	if ((((*code)&0xfc000000) == 0x0c000000)
-	    || (((*code)&0xfc1f003f) == 0x00000009)) {
-		mips_nop (code);
-		mono_arch_flush_icache (code-1, 4);
+	if ((((*code32)&0xfc000000) == 0x0c000000)
+	    || (((*code32)&0xfc1f003f) == 0x00000009)) {
+		mips_nop (code32);
+		mono_arch_flush_icache ((gpointer)(code32 - 1), 4);
 		return;
-	} else {
-		g_assert_not_reached ();
 	}
+	g_assert_not_reached ();
+}
+
+gpointer
+mono_arch_get_nullified_class_init_trampoline (MonoTrampInfo **info)
+{
+	guint8 *buf, *code;
+
+	code = buf = mono_global_codeman_reserve (16);
+
+	mips_jr (code, mips_ra);
+	mips_nop (code);
+
+	mono_arch_flush_icache (buf, code - buf);
+
+	if (info)
+		*info = mono_tramp_info_create (g_strdup_printf ("nullified_class_init_trampoline"), buf, code - buf, NULL, NULL);
+
+	return buf;
 }
 
 /*
@@ -229,26 +174,52 @@ mips_class_init_trampoline (void *vtable, guint32 *code, char *sp)
  *  -------------------
  */
 guchar*
-mono_arch_create_trampoline_code (MonoTrampolineType tramp_type)
+mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
 {
-	guint8 *buf, *code = NULL;
-	int i, offset, lmf;
+	guint8 *buf, *tramp, *code = NULL;
+	int i, lmf;
+	GSList *unwind_ops = NULL;
+	MonoJumpInfo *ji = NULL;
+	int max_code_len = 768;
+
+	/* AOT not supported on MIPS yet */
+	g_assert (!aot);
 
 	/* Now we'll create in 'buf' the MIPS trampoline code. This
 	   is the trampoline code common to all methods  */
-		
-	code = buf = mono_global_codeman_reserve (512);
-		
+
+	code = buf = mono_global_codeman_reserve (max_code_len);
+
 	/* Allocate the stack frame, and save the return address */
 	mips_addiu (code, mips_sp, mips_sp, -STACK);
 	mips_sw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
 
+	/* we build the MonoLMF structure on the stack - see mini-mips.h */
 	/* offset of MonoLMF from sp */
-	lmf = STACK - sizeof (MonoLMF);
+	lmf = STACK - sizeof (MonoLMF) - 8;
+
 	for (i = 0; i < MONO_MAX_IREGS; i++)
-		mips_sw (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
+		MIPS_SW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
 	for (i = 0; i < MONO_MAX_FREGS; i++)
-		mips_swc1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
+		MIPS_SWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
+
+	/* Set the magic number */
+	mips_load_const (code, mips_at, MIPS_LMF_MAGIC2);
+	mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, magic));
+
+	/* Save caller sp */
+	mips_addiu (code, mips_at, mips_sp, STACK);
+	MIPS_SW (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[mips_sp]));
+
+	/* save method info (it was in t8) */
+	mips_sw (code, mips_t8, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, method));
+
+	/* save the IP (caller ip) */
+	if (tramp_type == MONO_TRAMPOLINE_JUMP) {
+		mips_sw (code, mips_zero, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
+	} else {
+		mips_sw (code, mips_ra, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
+	}
 
 	/* jump to mono_get_lmf_addr here */
 	mips_load (code, mips_t9, mono_get_lmf_addr);
@@ -257,61 +228,45 @@ mono_arch_create_trampoline_code (MonoTrampolineType tramp_type)
 
 	/* v0 now points at the (MonoLMF **) for the current thread */
 
-	/* we build the MonoLMF structure on the stack - see mini-mips.h
-	 * The pointer to the struct is put in mips_s0 (new_lmf).
-	 */
-
-	mips_addiu (code, mips_t2, mips_sp, lmf);
-
 	/* new_lmf->lmf_addr = lmf_addr -- useful when unwinding */
-	mips_sw (code, mips_v0, mips_t2, G_STRUCT_OFFSET(MonoLMF, lmf_addr));
+	mips_sw (code, mips_v0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
 
 	/* new_lmf->previous_lmf = *lmf_addr */
 	mips_lw (code, mips_at, mips_v0, 0);
-	mips_sw (code, mips_at, mips_t2, G_STRUCT_OFFSET(MonoLMF, previous_lmf));
-
-	/* *(lmf_addr) = t2 */
-	mips_sw (code, mips_t2, mips_v0, 0);
-
-	/* save method info (it was in t8) */
-	mips_lw (code, mips_at, mips_t2, G_STRUCT_OFFSET(MonoLMF, iregs[mips_t8]));
-	mips_sw (code, mips_at, mips_t2, G_STRUCT_OFFSET(MonoLMF, method));
+	mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
 
-	mips_sw (code, mips_sp, mips_t2, G_STRUCT_OFFSET(MonoLMF, ebp));
-
-	/* save the IP (caller ip) */
-	if (tramp_type == MONO_TRAMPOLINE_JUMP) {
-		mips_sw (code, mips_zero, mips_t2, G_STRUCT_OFFSET(MonoLMF, eip));
-	} else {
-		mips_lw (code, mips_at, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
-		mips_sw (code, mips_at, mips_t2, G_STRUCT_OFFSET(MonoLMF, eip));
-	}
+	/* *(lmf_addr) = new_lmf */
+	mips_addiu (code, mips_at, mips_sp, lmf);
+	mips_sw (code, mips_at, mips_v0, 0);
 
 	/*
 	 * Now we're ready to call mips_magic_trampoline ().
 	 */
 
-	/* Arg 1: MonoMethod *method. */
-	mips_lw (code, mips_a0, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[mips_t8]));
-		
+	/* Arg 1: pointer to registers so that the magic trampoline can
+	 * access what we saved above
+	 */
+	mips_addiu (code, mips_a0, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[0]));
+
 	/* Arg 2: code (next address to the instruction that called us) */
 	if (tramp_type == MONO_TRAMPOLINE_JUMP) {
 		mips_move (code, mips_a1, mips_zero);
 	} else {
 		mips_lw (code, mips_a1, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
 	}
-		
-	/* Arg 3: stack pointer so that the magic trampoline can access the
-	 * registers we saved above
-	 */
-	mips_move (code, mips_a2, mips_sp);
+
+	/* Arg 3: MonoMethod *method. */
+	if (tramp_type == MONO_TRAMPOLINE_GENERIC_CLASS_INIT)
+		mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs [mips_a0]));
+	else
+		mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, method));
+
+	/* Arg 4: Trampoline */
+	mips_move (code, mips_a3, mips_zero);
 		
 	/* Now go to the trampoline */
-	if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT) {
-		mips_load (code, mips_t9, (guint32)mips_class_init_trampoline);
-	} else {
-		mips_load (code, mips_t9, (guint32)mips_magic_trampoline);
-	}
+	tramp = (guint8*)mono_get_trampoline_func (tramp_type);
+	mips_load (code, mips_t9, (guint32)tramp);
 	mips_jalr (code, mips_t9, mips_ra);
 	mips_nop (code);
 		
@@ -332,42 +287,55 @@ mono_arch_create_trampoline_code (MonoTrampolineType tramp_type)
 	/* Restore the callee-saved & argument registers */
 	for (i = 0; i < MONO_MAX_IREGS; i++) {
 		if ((MONO_ARCH_CALLEE_SAVED_REGS | MONO_ARCH_CALLEE_REGS | MIPS_ARG_REGS) & (1 << i))
-		    mips_lw (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
+		    MIPS_LW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
 	}
-	/* XXX - Restore the float registers */
+	for (i = 0; i < MONO_MAX_FREGS; i++)
+		MIPS_LWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
 
 	/* Non-standard function epilogue. Instead of doing a proper
 	 * return, we just jump to the compiled code.
 	 */
 	/* Restore ra & stack pointer, and jump to the code */
 
+	if (tramp_type == MONO_TRAMPOLINE_RGCTX_LAZY_FETCH)
+		mips_move (code, mips_v0, mips_at);
 	mips_lw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
 	mips_addiu (code, mips_sp, mips_sp, STACK);
-	mips_jr (code, mips_at);
+	if (MONO_TRAMPOLINE_TYPE_MUST_RETURN (tramp_type))
+		mips_jr (code, mips_ra);
+	else
+		mips_jr (code, mips_at);
 	mips_nop (code);
 
 	/* Flush instruction cache, since we've generated code */
 	mono_arch_flush_icache (buf, code - buf);
 	
 	/* Sanity check */
-	g_assert ((code - buf) <= 512);
+	g_assert ((code - buf) <= max_code_len);
+
+	if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT)
+		/* Initialize the nullified class init trampoline used in the AOT case */
+		nullified_class_init_trampoline = mono_arch_get_nullified_class_init_trampoline (NULL);
+
+	if (info)
+		*info = mono_tramp_info_create (mono_get_generic_trampoline_name (tramp_type), buf, code - buf, ji, unwind_ops);
 
 	return buf;
 }
 
-static MonoJitInfo*
-create_specific_tramp (MonoMethod *method, guint8* tramp, MonoDomain *domain) {
-	guint8 *code, *buf;
-	MonoJitInfo *ji;
+gpointer
+mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
+{
+	guint8 *code, *buf, *tramp;
+
+	tramp = mono_get_trampoline_code (tramp_type);
 
-	mono_domain_lock (domain);
-	code = buf = mono_code_manager_reserve (domain->code_mp, 32);
-	mono_domain_unlock (domain);
+	code = buf = mono_domain_code_reserve (domain, 32);
 
 	/* Prepare the jump to the generic trampoline code
 	 * mono_arch_create_trampoline_code() knows we're putting this in t8
 	 */
-	mips_load (code, mips_t8, method);
+	mips_load (code, mips_t8, arg1);
 	
 	/* Now jump to the generic trampoline code */
 	mips_load (code, mips_at, tramp);
@@ -379,137 +347,199 @@ create_specific_tramp (MonoMethod *method, guint8* tramp, MonoDomain *domain) {
 
 	g_assert ((code - buf) <= 32);
 
-	ji = g_new0 (MonoJitInfo, 1);
-	ji->method = method;
-	ji->code_start = buf;
-	ji->code_size = code - buf;
-
-	mono_jit_stats.method_trampolines++;
-
-	return ji;
-}
+	if (code_len)
+		*code_len = code - buf;
 
-MonoJitInfo*
-mono_arch_create_jump_trampoline (MonoMethod *method)
-{
-	guint8 *tramp;
-	MonoDomain* domain = mono_domain_get ();
-	
-	tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_JUMP);
-	return create_specific_tramp (method, tramp, domain);
+	return buf;
 }
 
-/**
- * arch_create_jit_trampoline:
- * @method: pointer to the method info
- *
- * Creates a trampoline function for virtual methods. If the created
- * code is called it first starts JIT compilation of method,
- * and then calls the newly created method. It also replaces the
- * corresponding vtable entry (see mips_magic_trampoline).
- *
- * A trampoline consists of two parts: a main fragment, shared by all method
- * trampolines, and some code specific to each method, which hard-codes a
- * reference to that method and then calls the main fragment.
- *
- * The main fragment contains a call to 'mips_magic_trampoline', which performs
- * call to the JIT compiler and substitutes the method-specific fragment with
- * some code that directly calls the JIT-compiled method.
- * 
- * Returns: a pointer to the newly created code 
- */
 gpointer
-mono_arch_create_jit_trampoline (MonoMethod *method)
+mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
 {
-	guint8 *tramp;
-	MonoJitInfo *ji;
-	MonoDomain* domain = mono_domain_get ();
-	gpointer code_start;
+	guint8 *code, *start;
+	int buf_len;
 
-	tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_GENERIC);
-	/* FIXME: should pass the domain down to this function */
-	ji = create_specific_tramp (method, tramp, domain);
-	code_start = ji->code_start;
-	g_free (ji);
+	MonoDomain *domain = mono_domain_get ();
+
+	buf_len = 24;
+
+	start = code = mono_domain_code_reserve (domain, buf_len);
+
+	mips_load (code, MONO_ARCH_RGCTX_REG, mrgctx);
+	mips_load (code, mips_at, addr);
+	mips_jr (code, mips_at);
+	mips_nop (code);
 
-	return code_start;
+	g_assert ((code - start) <= buf_len);
+
+	mono_arch_flush_icache (start, code - start);
+
+	return start;
 }
 
-/**
- * mono_arch_create_class_init_trampoline:
- *  @vtable: the type to initialize
- *
- * Creates a trampoline function to run a type initializer. 
- * If the trampoline is called, it calls mono_runtime_class_init with the
- * given vtable, then patches the caller code so it does not get called any
- * more.
- * 
- * Returns: a pointer to the newly created code 
- */
 gpointer
-mono_arch_create_class_init_trampoline (MonoVTable *vtable)
+mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
 {
-	guint8 *code, *buf, *tramp;
+	guint8 *tramp;
+	guint8 *code, *buf;
+	int tramp_size;
+	guint32 code_len;
+	guint8 **rgctx_null_jumps;
+	int depth, index;
+	int i, njumps;
+	gboolean mrgctx;
+	MonoJumpInfo *ji = NULL;
+	GSList *unwind_ops = NULL;
+
+	mrgctx = MONO_RGCTX_SLOT_IS_MRGCTX (slot);
+	index = MONO_RGCTX_SLOT_INDEX (slot);
+	if (mrgctx)
+		index += MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT / sizeof (gpointer);
+	for (depth = 0; ; ++depth) {
+		int size = mono_class_rgctx_get_array_size (depth, mrgctx);
+
+		if (index < size - 1)
+			break;
+		index -= size - 1;
+	}
 
-	tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_CLASS_INIT);
+	tramp_size = 64 + 16 * depth;
 
-	/* This is the method-specific part of the trampoline. Its purpose is
-	to provide the generic part with the MonoMethod *method pointer. We'll
-	use r11 to keep that value, for instance. However, the generic part of
-	the trampoline relies on r11 having the same value it had before coming
-	here, so we must save it before. */
-	mono_domain_lock (vtable->domain);
-	code = buf = mono_code_manager_reserve (vtable->domain->code_mp, METHOD_TRAMPOLINE_SIZE);
-	mono_domain_unlock (vtable->domain);
+	code = buf = mono_global_codeman_reserve (tramp_size);
 
-	//g_print ("mips_class_init_tramp buf=%p tramp=%p\n", buf, tramp);
+	mono_add_unwind_op_def_cfa (unwind_ops, code, buf, mips_sp, 0);
 
-	mips_addiu (code, mips_sp, mips_sp, -MIPS_MINIMAL_STACK_SIZE);
-	mips_sw (code, mips_ra, mips_sp, MIPS_MINIMAL_STACK_SIZE + MIPS_RET_ADDR_OFFSET);
+	rgctx_null_jumps = g_malloc (sizeof (guint8*) * (depth + 2));
+	njumps = 0;
 
-	/* Probably need to save/restore a0-a3 here */
+	/* The vtable/mrgctx is in a0 */
+	g_assert (MONO_ARCH_VTABLE_REG == mips_a0);
+	if (mrgctx) {
+		/* get mrgctx ptr */
+		mips_move (code, mips_a1, mips_a0);
+ 	} else {
+		/* load rgctx ptr from vtable */
+		g_assert (mips_is_imm16 (G_STRUCT_OFFSET (MonoVTable, runtime_generic_context)));
+		mips_lw (code, mips_a1, mips_a0, G_STRUCT_OFFSET (MonoVTable, runtime_generic_context));
+		/* is the rgctx ptr null? */
+		/* if yes, jump to actual trampoline */
+		rgctx_null_jumps [njumps ++] = code;
+		mips_beq (code, mips_a1, mips_zero, 0);
+		mips_nop (code);
+	}
 
-	mips_load (code, mips_a0, vtable);
-	mips_move (code, mips_a1, mips_ra);
-	mips_move (code, mips_a2, mips_zero);
+	for (i = 0; i < depth; ++i) {
+		/* load ptr to next array */
+		if (mrgctx && i == 0) {
+			g_assert (mips_is_imm16 (MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT));
+			mips_lw (code, mips_a1, mips_a1, MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT);
+		} else {
+			mips_lw (code, mips_a1, mips_a1, 0);
+		}
+		/* is the ptr null? */
+		/* if yes, jump to actual trampoline */
+		rgctx_null_jumps [njumps ++] = code;
+		mips_beq (code, mips_a1, mips_zero, 0);
+		mips_nop (code);
+	}
 
-	mips_load (code, mips_t9, mips_class_init_trampoline);
-	mips_jalr (code, mips_t9, mips_ra);
+	/* fetch slot */
+	g_assert (mips_is_imm16 (sizeof (gpointer) * (index + 1)));
+	mips_lw (code, mips_a1, mips_a1, sizeof (gpointer) * (index + 1));
+	/* is the slot null? */
+	/* if yes, jump to actual trampoline */
+	rgctx_null_jumps [njumps ++] = code;
+	mips_beq (code, mips_a1, mips_zero, 0);
 	mips_nop (code);
-
-	mips_lw (code, mips_ra, mips_sp, MIPS_MINIMAL_STACK_SIZE + MIPS_RET_ADDR_OFFSET);
-	mips_addiu (code, mips_sp, mips_sp, MIPS_MINIMAL_STACK_SIZE);
+	/* otherwise return, result is in R1 */
+	mips_move (code, mips_v0, mips_a1);
 	mips_jr (code, mips_ra);
 	mips_nop (code);
 
-	/* Flush instruction cache, since we've generated code */
+	g_assert (njumps <= depth + 2);
+	for (i = 0; i < njumps; ++i)
+		mips_patch ((guint32*)rgctx_null_jumps [i], (guint32)code);
+
+	g_free (rgctx_null_jumps);
+
+	/* Slowpath */
+
+	/* The vtable/mrgctx is still in a0 */
+
+	if (aot) {
+		ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, g_strdup_printf ("specific_trampoline_lazy_fetch_%u", slot));
+		mips_load (code, mips_at, 0);
+		mips_jr (code, mips_at);
+		mips_nop (code);
+	} else {
+		tramp = mono_arch_create_specific_trampoline (GUINT_TO_POINTER (slot), MONO_TRAMPOLINE_RGCTX_LAZY_FETCH, mono_get_root_domain (), &code_len);
+		mips_load (code, mips_at, tramp);
+		mips_jr (code, mips_at);
+		mips_nop (code);
+	}
+
 	mono_arch_flush_icache (buf, code - buf);
-		
-	/* Sanity check */
-	g_assert ((code - buf) <= METHOD_TRAMPOLINE_SIZE);
-	mono_jit_stats.method_trampolines++;
+
+	g_assert (code - buf <= tramp_size);
+
+	if (info)
+		*info = mono_tramp_info_create (mono_get_rgctx_fetch_trampoline_name (slot), buf, code - buf, ji, unwind_ops);
 
 	return buf;
 }
 
-/*
- * This method is only called when running in the Mono Debugger.
- */
 gpointer
-mono_debugger_create_notification_function (void)
+mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
 {
-#if 0
-	guint8 *ptr, *buf;
-
-	codeman = mono_global_codeman_reserve (16);
-	mips_break (buf, 0xd0);
-	mips_jr (buf, mips_ra);
-	mips_nop (buf);
-	mono_arch_flush_icache (ptr, buf - ptr);
-
-	return ptr;
-#else
-	return NULL;
-#endif
-}
+	guint8 *tramp;
+	guint8 *code, *buf;
+	static int byte_offset = -1;
+	static guint8 bitmask;
+	guint8 *jump;
+	int tramp_size;
+	guint32 code_len;
+	GSList *unwind_ops = NULL;
+	MonoJumpInfo *ji = NULL;
+
+	tramp_size = 64;
+
+	code = buf = mono_global_codeman_reserve (tramp_size);
+
+	if (byte_offset < 0)
+		mono_marshal_find_bitfield_offset (MonoVTable, initialized, &byte_offset, &bitmask);
+
+	/* if (!(vtable->initialized)) */
+	mips_lbu (code, mips_at, MONO_ARCH_VTABLE_REG, byte_offset);
+	g_assert (!(bitmask & 0xffff0000));
+	mips_andi (code, mips_at, mips_at, bitmask);
+	jump = code;
+	mips_beq (code, mips_at, mips_zero, 0);
+	mips_nop (code);
+	/* Initialized case */
+	mips_jr (code, mips_ra);
+	mips_nop (code);
 
+	/* Uninitialized case */
+	mips_patch ((guint32*)jump, (guint32)code);
+
+	if (aot) {
+		ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "specific_trampoline_generic_class_init");
+		mips_load (code, mips_at, 0);
+		mips_jr (code, mips_at);
+		mips_nop (code);
+	} else {
+		tramp = mono_arch_create_specific_trampoline (NULL, MONO_TRAMPOLINE_GENERIC_CLASS_INIT, mono_get_root_domain (), &code_len);
+		mips_load (code, mips_at, tramp);
+		mips_jr (code, mips_at);
+		mips_nop (code);
+	}
+
+	mono_arch_flush_icache (buf, code - buf);
+
+	g_assert (code - buf <= tramp_size);
+
+	if (info)
+		*info = mono_tramp_info_create (g_strdup_printf ("generic_class_init_trampoline"), buf, code - buf, ji, unwind_ops);
+
+	return buf;
+}