MIPS: pre-crankshaft updates to code-stubs and stub-cache (3/3)

src/mips/code-stubs-mips.cc

Index: src/mips/code-stubs-mips.cc
diff --git a/src/mips/code-stubs-mips.cc b/src/mips/code-stubs-mips.cc
index 521b8e58f05cecb8ce684b009499a46ee4b22b77..4f81a9e42dac99d79682716827d6505974aaac11 100644
--- a/src/mips/code-stubs-mips.cc
+++ b/src/mips/code-stubs-mips.cc
@@ -615,7 +615,7 @@ void FloatingPointHelper::ConvertIntToDouble(MacroAssembler* masm,
 void FloatingPointHelper::LoadNumberAsInt32Double(MacroAssembler* masm,
                                                   Register object,
                                                   Destination destination,
-                                                  FPURegister double_dst,
+                                                  DoubleRegister double_dst,
                                                   Register dst1,
                                                   Register dst2,
                                                   Register heap_number_map,
@@ -651,25 +651,16 @@ void FloatingPointHelper::LoadNumberAsInt32Double(MacroAssembler* masm,
     // Load the double value.
     __ ldc1(double_dst, FieldMemOperand(object, HeapNumber::kValueOffset));
 
-    // NOTE: ARM uses a MacroAssembler function here (EmitVFPTruncate).
-    // On MIPS a lot of things cannot be implemented the same way so right
-    // now it makes a lot more sense to just do things manually.
-
-    // Save FCSR.
-    __ cfc1(scratch1, FCSR);
-    // Disable FPU exceptions.
-    __ ctc1(zero_reg, FCSR);
-    __ trunc_w_d(single_scratch, double_dst);
-    // Retrieve FCSR.
-    __ cfc1(scratch2, FCSR);
-    // Restore FCSR.
-    __ ctc1(scratch1, FCSR);
-
-    // Check for inexact conversion or exception.
-    __ And(scratch2, scratch2, kFCSRFlagMask);
+    Register except_flag = scratch2;
+    __ EmitFPUTruncate(kRoundToZero,
+                       single_scratch,
+                       double_dst,
+                       scratch1,
+                       except_flag,
+                       kCheckForInexactConversion);
 
     // Jump to not_int32 if the operation did not succeed.
-    __ Branch(not_int32, ne, scratch2, Operand(zero_reg));
+    __ Branch(not_int32, ne, except_flag, Operand(zero_reg));
 
     if (destination == kCoreRegisters) {
       __ Move(dst1, dst2, double_dst);
@@ -706,7 +697,7 @@ void FloatingPointHelper::LoadNumberAsInt32(MacroAssembler* masm,
                                             Register scratch1,
                                             Register scratch2,
                                             Register scratch3,
-                                            FPURegister double_scratch,
+                                            DoubleRegister double_scratch,
                                             Label* not_int32) {
   ASSERT(!dst.is(object));
   ASSERT(!scratch1.is(object) && !scratch2.is(object) && !scratch3.is(object));
@@ -735,27 +726,19 @@ void FloatingPointHelper::LoadNumberAsInt32(MacroAssembler* masm,
     // Load the double value.
     __ ldc1(double_scratch, FieldMemOperand(object, HeapNumber::kValueOffset));
 
-    // NOTE: ARM uses a MacroAssembler function here (EmitVFPTruncate).
-    // On MIPS a lot of things cannot be implemented the same way so right
-    // now it makes a lot more sense to just do things manually.
-
-    // Save FCSR.
-    __ cfc1(scratch1, FCSR);
-    // Disable FPU exceptions.
-    __ ctc1(zero_reg, FCSR);
-    __ trunc_w_d(double_scratch, double_scratch);
-    // Retrieve FCSR.
-    __ cfc1(scratch2, FCSR);
-    // Restore FCSR.
-    __ ctc1(scratch1, FCSR);
-
-    // Check for inexact conversion or exception.
-    __ And(scratch2, scratch2, kFCSRFlagMask);
+    FPURegister single_scratch = double_scratch.low();
+    Register except_flag = scratch2;
+    __ EmitFPUTruncate(kRoundToZero,
+                       single_scratch,
+                       double_scratch,
+                       scratch1,
+                       except_flag,
+                       kCheckForInexactConversion);
 
     // Jump to not_int32 if the operation did not succeed.
-    __ Branch(not_int32, ne, scratch2, Operand(zero_reg));
+    __ Branch(not_int32, ne, except_flag, Operand(zero_reg));
     // Get the result in the destination register.
-    __ mfc1(dst, double_scratch);
+    __ mfc1(dst, single_scratch);
 
   } else {
     // Load the double value in the destination registers.
@@ -883,7 +866,7 @@ void FloatingPointHelper::CallCCodeForDoubleOperation(
   }
   // Call C routine that may not cause GC or other trouble.
   __ CallCFunction(ExternalReference::double_fp_operation(op, masm->isolate()),
-                   4);
+                   0, 2);
   // Store answer in the overwritable heap number.
   if (!IsMipsSoftFloatABI) {
     CpuFeatures::Scope scope(FPU);
@@ -1258,7 +1241,7 @@ static void EmitTwoNonNanDoubleComparison(MacroAssembler* masm, Condition cc) {
 
   if (!CpuFeatures::IsSupported(FPU)) {
     __ push(ra);
-    __ PrepareCallCFunction(4, t4);  // Two doubles count as 4 arguments.
+    __ PrepareCallCFunction(0, 2, t4);  // Two doubles count as 4 arguments.

[Erik Corry, 2011/09/14 13:48:57]

Comment out of date?

[Paul Lind, 2011/09/15 05:49:25]

Yep, Done.

     if (!IsMipsSoftFloatABI) {
       // We are not using MIPS FPU instructions, and parameters for the runtime
       // function call are prepaired in a0-a3 registers, but function we are
@@ -1268,19 +1251,15 @@ static void EmitTwoNonNanDoubleComparison(MacroAssembler* masm, Condition cc) {
       __ Move(f12, a0, a1);
       __ Move(f14, a2, a3);
     }
-    __ CallCFunction(ExternalReference::compare_doubles(masm->isolate()), 4);
+    __ CallCFunction(ExternalReference::compare_doubles(masm->isolate()),
+       0, 2);
     __ pop(ra);  // Because this function returns int, result is in v0.
     __ Ret();
   } else {
     CpuFeatures::Scope scope(FPU);
     Label equal, less_than;
-    __ c(EQ, D, f12, f14);
-    __ bc1t(&equal);
-    __ nop();
-
-    __ c(OLT, D, f12, f14);
-    __ bc1t(&less_than);
-    __ nop();
+    __ BranchF(&equal, NULL, eq, f12, f14);
+    __ BranchF(&less_than, NULL, lt, f12, f14);
 
     // Not equal, not less, not NaN, must be greater.
     __ li(v0, Operand(GREATER));
@@ -1473,9 +1452,7 @@ void NumberToStringStub::GenerateLookupNumberStringCache(MacroAssembler* masm,
       __ JumpIfSmi(probe, not_found);
       __ ldc1(f12, FieldMemOperand(object, HeapNumber::kValueOffset));
       __ ldc1(f14, FieldMemOperand(probe, HeapNumber::kValueOffset));
-      __ c(EQ, D, f12, f14);
-      __ bc1t(&load_result_from_cache);
-      __ nop();   // bc1t() requires explicit fill of branch delay slot.
+      __ BranchF(&load_result_from_cache, NULL, eq, f12, f14);
       __ Branch(not_found);
     } else {
       // Note that there is no cache check for non-FPU case, even though
@@ -1591,9 +1568,7 @@ void CompareStub::Generate(MacroAssembler* masm) {
     __ li(t2, Operand(EQUAL));
 
     // Check if either rhs or lhs is NaN.
-    __ c(UN, D, f12, f14);
-    __ bc1t(&nan);
-    __ nop();
+    __ BranchF(NULL, &nan, eq, f12, f14);
 
     // Check if LESS condition is satisfied. If true, move conditionally
     // result to v0.
@@ -1711,89 +1686,116 @@ void CompareStub::Generate(MacroAssembler* masm) {
 }
 
 
-// The stub returns zero for false, and a non-zero value for true.
+// The stub expects its argument in the tos_ register and returns its result in
+// it, too: zero for false, and a non-zero value for true.
 void ToBooleanStub::Generate(MacroAssembler* masm) {
   // This stub uses FPU instructions.
   CpuFeatures::Scope scope(FPU);
 
-  Label false_result;
-  Label not_heap_number;
-  Register scratch0 = t5.is(tos_) ? t3 : t5;
-
-  // undefined -> false
-  __ LoadRoot(scratch0, Heap::kUndefinedValueRootIndex);
-  __ Branch(&false_result, eq, tos_, Operand(scratch0));
-
-  // Boolean -> its value
-  __ LoadRoot(scratch0, Heap::kFalseValueRootIndex);
-  __ Branch(&false_result, eq, tos_, Operand(scratch0));
-  __ LoadRoot(scratch0, Heap::kTrueValueRootIndex);
-  // "tos_" is a register and contains a non-zero value.  Hence we implicitly
-  // return true if the equal condition is satisfied.
-  __ Ret(eq, tos_, Operand(scratch0));
-
-  // Smis: 0 -> false, all other -> true
-  __ And(scratch0, tos_, tos_);
-  __ Branch(&false_result, eq, scratch0, Operand(zero_reg));
-  __ And(scratch0, tos_, Operand(kSmiTagMask));
-  // "tos_" is a register and contains a non-zero value.  Hence we implicitly
-  // return true if the not equal condition is satisfied.
-  __ Ret(eq, scratch0, Operand(zero_reg));
-
-  // 'null' -> false
-  __ LoadRoot(scratch0, Heap::kNullValueRootIndex);
-  __ Branch(&false_result, eq, tos_, Operand(scratch0));
-
-  // HeapNumber => false if +0, -0, or NaN.
-  __ lw(scratch0, FieldMemOperand(tos_, HeapObject::kMapOffset));
-  __ LoadRoot(at, Heap::kHeapNumberMapRootIndex);
-  __ Branch(&not_heap_number, ne, scratch0, Operand(at));
-
-  __ ldc1(f12, FieldMemOperand(tos_, HeapNumber::kValueOffset));
-  __ fcmp(f12, 0.0, UEQ);
-
-  // "tos_" is a register, and contains a non zero value by default.
-  // Hence we only need to overwrite "tos_" with zero to return false for
-  // FP_ZERO or FP_NAN cases. Otherwise, by default it returns true.
-  __ movt(tos_, zero_reg);
-  __ Ret();
+  Label patch;
+  const Register map = t5.is(tos_) ? t3 : t5;
 
-  __ bind(&not_heap_number);
-
-  // It can be an undetectable object.
-  // Undetectable => false.
-  __ lw(at, FieldMemOperand(tos_, HeapObject::kMapOffset));
-  __ lbu(scratch0, FieldMemOperand(at, Map::kBitFieldOffset));
-  __ And(scratch0, scratch0, Operand(1 << Map::kIsUndetectable));
-  __ Branch(&false_result, eq, scratch0, Operand(1 << Map::kIsUndetectable));
-
-  // JavaScript object => true.
-  __ lw(scratch0, FieldMemOperand(tos_, HeapObject::kMapOffset));
-  __ lbu(scratch0, FieldMemOperand(scratch0, Map::kInstanceTypeOffset));
-
-  // "tos_" is a register and contains a non-zero value.
-  // Hence we implicitly return true if the greater than
-  // condition is satisfied.
-  __ Ret(ge, scratch0, Operand(FIRST_SPEC_OBJECT_TYPE));
-
-  // Check for string.
-  __ lw(scratch0, FieldMemOperand(tos_, HeapObject::kMapOffset));
-  __ lbu(scratch0, FieldMemOperand(scratch0, Map::kInstanceTypeOffset));
-  // "tos_" is a register and contains a non-zero value.
-  // Hence we implicitly return true if the greater than
-  // condition is satisfied.
-  __ Ret(ge, scratch0, Operand(FIRST_NONSTRING_TYPE));
-
-  // String value => false iff empty, i.e., length is zero.
-  __ lw(tos_, FieldMemOperand(tos_, String::kLengthOffset));
-  // If length is zero, "tos_" contains zero ==> false.
-  // If length is not zero, "tos_" contains a non-zero value ==> true.
-  __ Ret();
+  // undefined -> false.
+  CheckOddball(masm, UNDEFINED, Heap::kUndefinedValueRootIndex, false);
 
-  // Return 0 in "tos_" for false.
-  __ bind(&false_result);
-  __ mov(tos_, zero_reg);
-  __ Ret();
+  // Boolean -> its value.
+  CheckOddball(masm, BOOLEAN, Heap::kFalseValueRootIndex, false);
+  CheckOddball(masm, BOOLEAN, Heap::kTrueValueRootIndex, true);
+
+  // 'null' -> false.
+  CheckOddball(masm, NULL_TYPE, Heap::kNullValueRootIndex, false);
+
+  if (types_.Contains(SMI)) {
+    // Smis: 0 -> false, all other -> true
+    __ And(at, tos_, kSmiTagMask);
+    // tos_ contains the correct return value already
+    __ Ret(eq, at, Operand(zero_reg));
+  } else if (types_.NeedsMap()) {
+    // If we need a map later and have a Smi -> patch.
+    __ JumpIfSmi(tos_, &patch);
+  }
+
+  if (types_.NeedsMap()) {
+    __ lw(map, FieldMemOperand(tos_, HeapObject::kMapOffset));
+
+    if (types_.CanBeUndetectable()) {
+      __ lbu(at, FieldMemOperand(map, Map::kBitFieldOffset));
+      __ And(at, at, Operand(1 << Map::kIsUndetectable));
+      // Undetectable -> false.
+      __   movn(tos_, zero_reg, at);
+      __ Ret(ne, at, Operand(zero_reg));
+    }
+  }
+
+  if (types_.Contains(SPEC_OBJECT)) {
+    // Spec object -> true.
+    __ lbu(at, FieldMemOperand(map, Map::kInstanceTypeOffset));
+    // tos_ contains the correct non-zero return value already.
+    __ Ret(ge, at, Operand(FIRST_SPEC_OBJECT_TYPE));
+  }
+
+  if (types_.Contains(STRING)) {
+    // String value -> false iff empty.
+    __ lbu(at, FieldMemOperand(map, Map::kInstanceTypeOffset));
+    Label skip;
+    __ Branch(&skip, ge, at, Operand(FIRST_NONSTRING_TYPE));
+    __ lw(tos_, FieldMemOperand(tos_, String::kLengthOffset));
+    __ Ret();  // the string length is OK as the return value
+    __ bind(&skip);
+  }
+
+  if (types_.Contains(HEAP_NUMBER)) {
+    // Heap number -> false iff +0, -0, or NaN.
+    Label not_heap_number;
+    __ LoadRoot(at, Heap::kHeapNumberMapRootIndex);
+    __ Branch(&not_heap_number, ne, map, Operand(at));
+    Label zero_or_nan, number;
+    __ ldc1(f2, FieldMemOperand(tos_, HeapNumber::kValueOffset));
+    __ BranchF(&number, &zero_or_nan, ne, f2, kDoubleRegZero);
+    // "tos_" is a register, and contains a non zero value by default.
+    // Hence we only need to overwrite "tos_" with zero to return false for
+    // FP_ZERO or FP_NAN cases. Otherwise, by default it returns true.
+    __ bind(&zero_or_nan);
+    __ mov(tos_, zero_reg);
+    __ bind(&number);
+    __ Ret();
+    __ bind(&not_heap_number);
+  }
+
+  __ bind(&patch);
+  GenerateTypeTransition(masm);
+}
+
+
+void ToBooleanStub::CheckOddball(MacroAssembler* masm,
+                                 Type type,
+                                 Heap::RootListIndex value,
+                                 bool result) {
+  if (types_.Contains(type)) {
+    // If we see an expected oddball, return its ToBoolean value tos_.
+    __ LoadRoot(at, value);
+    __ Subu(at, at, tos_);  // This is a check for equality for the movz below.
+    // The value of a root is never NULL, so we can avoid loading a non-null
+    // value into tos_ when we want to return 'true'.
+    if (!result) {
+      __ movz(tos_, zero_reg, at);
+    }
+    __ Ret(eq, at, Operand(zero_reg));
+  }
+}
+
+
+void ToBooleanStub::GenerateTypeTransition(MacroAssembler* masm) {
+  __ Move(a3, tos_);
+  __ li(a2, Operand(Smi::FromInt(tos_.code())));
+  __ li(a1, Operand(Smi::FromInt(types_.ToByte())));
+  __ Push(a3, a2, a1);
+  // Patch the caller to an appropriate specialized stub and return the
+  // operation result to the caller of the stub.
+  __ TailCallExternalReference(
+      ExternalReference(IC_Utility(IC::kToBoolean_Patch), masm->isolate()),
+      3,
+      1);
 }
 
 
@@ -2717,26 +2719,16 @@ void BinaryOpStub::GenerateInt32Stub(MacroAssembler* masm) {
           // Otherwise return a heap number if allowed, or jump to type
           // transition.
 
-          // NOTE: ARM uses a MacroAssembler function here (EmitVFPTruncate).
-          // On MIPS a lot of things cannot be implemented the same way so right
-          // now it makes a lot more sense to just do things manually.
-
-          // Save FCSR.
-          __ cfc1(scratch1, FCSR);
-          // Disable FPU exceptions.
-          __ ctc1(zero_reg, FCSR);
-          __ trunc_w_d(single_scratch, f10);
-          // Retrieve FCSR.
-          __ cfc1(scratch2, FCSR);
-          // Restore FCSR.
-          __ ctc1(scratch1, FCSR);
-
-          // Check for inexact conversion or exception.
-          __ And(scratch2, scratch2, kFCSRFlagMask);
+          Register except_flag = scratch2;
+          __ EmitFPUTruncate(kRoundToZero,
+                             single_scratch,
+                             f10,
+                             scratch1,
+                             except_flag);
 
           if (result_type_ <= BinaryOpIC::INT32) {
-            // If scratch2 != 0, result does not fit in a 32-bit integer.
-            __ Branch(&transition, ne, scratch2, Operand(zero_reg));
+            // If except_flag != 0, result does not fit in a 32-bit integer.
+            __ Branch(&transition, ne, except_flag, Operand(zero_reg));
           }
 
           // Check if the result fits in a smi.
@@ -3225,7 +3217,6 @@ void TranscendentalCacheStub::Generate(MacroAssembler* masm) {
     __ lw(t0, MemOperand(cache_entry, 0));
     __ lw(t1, MemOperand(cache_entry, 4));
     __ lw(t2, MemOperand(cache_entry, 8));
-    __ Addu(cache_entry, cache_entry, 12);
     __ Branch(&calculate, ne, a2, Operand(t0));
     __ Branch(&calculate, ne, a3, Operand(t1));
     // Cache hit. Load result, cleanup and return.
@@ -3259,13 +3250,13 @@ void TranscendentalCacheStub::Generate(MacroAssembler* masm) {
     // Register a0 holds precalculated cache entry address; preserve
     // it on the stack and pop it into register cache_entry after the
     // call.
-    __ push(cache_entry);
+    __ Push(cache_entry, a2, a3);
     GenerateCallCFunction(masm, scratch0);
     __ GetCFunctionDoubleResult(f4);
 
     // Try to update the cache. If we cannot allocate a
     // heap number, we return the result without updating.
-    __ pop(cache_entry);
+    __ Pop(cache_entry, a2, a3);
     __ LoadRoot(t1, Heap::kHeapNumberMapRootIndex);
     __ AllocateHeapNumber(t2, scratch0, scratch1, t1, &no_update);
     __ sdc1(f4, FieldMemOperand(t2, HeapNumber::kValueOffset));
@@ -3317,22 +3308,25 @@ void TranscendentalCacheStub::GenerateCallCFunction(MacroAssembler* masm,
   __ push(ra);
   __ PrepareCallCFunction(2, scratch);
   if (IsMipsSoftFloatABI) {
-    __ Move(v0, v1, f4);
+    __ Move(a0, a1, f4);
   } else {
     __ mov_d(f12, f4);
   }
   switch (type_) {
     case TranscendentalCache::SIN:
       __ CallCFunction(
-          ExternalReference::math_sin_double_function(masm->isolate()), 2);
+          ExternalReference::math_sin_double_function(masm->isolate()),
+          0, 1);
       break;
     case TranscendentalCache::COS:
       __ CallCFunction(
-          ExternalReference::math_cos_double_function(masm->isolate()), 2);
+          ExternalReference::math_cos_double_function(masm->isolate()),
+          0, 1);
       break;
     case TranscendentalCache::LOG:
       __ CallCFunction(
-          ExternalReference::math_log_double_function(masm->isolate()), 2);
+          ExternalReference::math_log_double_function(masm->isolate()),
+          0, 1);
       break;
     default:
       UNIMPLEMENTED();
@@ -3415,10 +3409,11 @@ void MathPowStub::Generate(MacroAssembler* masm) {
                           heapnumbermap,
                           &call_runtime);
     __ push(ra);
-    __ PrepareCallCFunction(3, scratch);
+    __ PrepareCallCFunction(1, 1, scratch);
     __ SetCallCDoubleArguments(double_base, exponent);
     __ CallCFunction(
-        ExternalReference::power_double_int_function(masm->isolate()), 3);
+        ExternalReference::power_double_int_function(masm->isolate()),
+        1, 1);
     __ pop(ra);
     __ GetCFunctionDoubleResult(double_result);
     __ sdc1(double_result,
@@ -3443,13 +3438,14 @@ void MathPowStub::Generate(MacroAssembler* masm) {
                           heapnumbermap,
                           &call_runtime);
     __ push(ra);
-    __ PrepareCallCFunction(4, scratch);
+    __ PrepareCallCFunction(0, 2, scratch);
     // ABI (o32) for func(double a, double b): a in f12, b in f14.
     ASSERT(double_base.is(f12));
     ASSERT(double_exponent.is(f14));
     __ SetCallCDoubleArguments(double_base, double_exponent);
     __ CallCFunction(
-        ExternalReference::power_double_double_function(masm->isolate()), 4);
+        ExternalReference::power_double_double_function(masm->isolate()),
+        0, 2);
     __ pop(ra);
     __ GetCFunctionDoubleResult(double_result);
     __ sdc1(double_result,
@@ -3493,9 +3489,10 @@ void CEntryStub::GenerateCore(MacroAssembler* masm,
   if (do_gc) {
     // Move result passed in v0 into a0 to call PerformGC.
     __ mov(a0, v0);
-    __ PrepareCallCFunction(1, a1);
+    __ PrepareCallCFunction(1, 0, a1);
     __ CallCFunction(
-        ExternalReference::perform_gc_function(masm->isolate()), 1);
+        ExternalReference::perform_gc_function(masm->isolate()),
+        1, 0);
   }
 
   ExternalReference scope_depth =
@@ -3699,8 +3696,11 @@ void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
     CpuFeatures::Scope scope(FPU);
     // Save callee-saved FPU registers.
     __ MultiPushFPU(kCalleeSavedFPU);
+    // Set up the reserved register for 0.0.
+    __ Move(kDoubleRegZero, 0.0);
   }
 
+
   // Load argv in s0 register.
   int offset_to_argv = (kNumCalleeSaved + 1) * kPointerSize;
   if (CpuFeatures::IsSupported(FPU)) {
@@ -3857,11 +3857,10 @@ void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
 // * object: a0 or at sp + 1 * kPointerSize.
 // * function: a1 or at sp.
 //
-// Inlined call site patching is a crankshaft-specific feature that is not
-// implemented on MIPS.
+// An inlined call site may have been generated before calling this stub.
+// In this case the offset to the inline site to patch is passed on the stack,
+// in the safepoint slot for register t0.
 void InstanceofStub::Generate(MacroAssembler* masm) {
-  // This is a crankshaft-specific feature that has not been implemented yet.
-  ASSERT(!HasCallSiteInlineCheck());
   // Call site inlining and patching implies arguments in registers.
   ASSERT(HasArgsInRegisters() || !HasCallSiteInlineCheck());
   // ReturnTrueFalse is only implemented for inlined call sites.
@@ -3875,6 +3874,8 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
   const Register inline_site = t5;
   const Register scratch = a2;
 
+  const int32_t kDeltaToLoadBoolResult = 4 * kPointerSize;
+
   Label slow, loop, is_instance, is_not_instance, not_js_object;
 
   if (!HasArgsInRegisters()) {
@@ -3890,10 +3891,10 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
   // real lookup and update the call site cache.
   if (!HasCallSiteInlineCheck()) {
     Label miss;
-    __ LoadRoot(t1, Heap::kInstanceofCacheFunctionRootIndex);
-    __ Branch(&miss, ne, function, Operand(t1));
-    __ LoadRoot(t1, Heap::kInstanceofCacheMapRootIndex);
-    __ Branch(&miss, ne, map, Operand(t1));
+    __ LoadRoot(at, Heap::kInstanceofCacheFunctionRootIndex);
+    __ Branch(&miss, ne, function, Operand(at));
+    __ LoadRoot(at, Heap::kInstanceofCacheMapRootIndex);
+    __ Branch(&miss, ne, map, Operand(at));
     __ LoadRoot(v0, Heap::kInstanceofCacheAnswerRootIndex);
     __ DropAndRet(HasArgsInRegisters() ? 0 : 2);
 
@@ -3913,7 +3914,15 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
     __ StoreRoot(function, Heap::kInstanceofCacheFunctionRootIndex);
     __ StoreRoot(map, Heap::kInstanceofCacheMapRootIndex);
   } else {
-    UNIMPLEMENTED_MIPS();
+    ASSERT(HasArgsInRegisters());
+    // Patch the (relocated) inlined map check.
+
+    // The offset was stored in t0 safepoint slot.
+    // (See LCodeGen::DoDeferredLInstanceOfKnownGlobal)
+    __ LoadFromSafepointRegisterSlot(scratch, t0);
+    __ Subu(inline_site, ra, scratch);
+    // Patch the relocated value to map.
+    __ PatchRelocatedValue(inline_site, scratch, map);
   }
 
   // Register mapping: a3 is object map and t0 is function prototype.
@@ -3939,7 +3948,16 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
     __ mov(v0, zero_reg);
     __ StoreRoot(v0, Heap::kInstanceofCacheAnswerRootIndex);
   } else {
-    UNIMPLEMENTED_MIPS();
+    // Patch the call site to return true.
+    __ LoadRoot(v0, Heap::kTrueValueRootIndex);
+    __ Addu(inline_site, inline_site, Operand(kDeltaToLoadBoolResult));
+    // Get the boolean result location in scratch and patch it.
+    __ PatchRelocatedValue(inline_site, scratch, v0);
+
+    if (!ReturnTrueFalseObject()) {
+      ASSERT_EQ(Smi::FromInt(0), 0);
+      __ mov(v0, zero_reg);
+    }
   }
   __ DropAndRet(HasArgsInRegisters() ? 0 : 2);
 
@@ -3948,8 +3966,17 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
     __ li(v0, Operand(Smi::FromInt(1)));
     __ StoreRoot(v0, Heap::kInstanceofCacheAnswerRootIndex);
   } else {
-    UNIMPLEMENTED_MIPS();
+    // Patch the call site to return false.
+    __ LoadRoot(v0, Heap::kFalseValueRootIndex);
+    __ Addu(inline_site, inline_site, Operand(kDeltaToLoadBoolResult));
+    // Get the boolean result location in scratch and patch it.
+    __ PatchRelocatedValue(inline_site, scratch, v0);
+
+    if (!ReturnTrueFalseObject()) {
+      __ li(v0, Operand(Smi::FromInt(1)));
+    }
   }
+
   __ DropAndRet(HasArgsInRegisters() ? 0 : 2);
 
   Label object_not_null, object_not_null_or_smi;
@@ -6464,25 +6491,15 @@ void ICCompareStub::GenerateHeapNumbers(MacroAssembler* masm) {
     __ ldc1(f2, MemOperand(a2, HeapNumber::kValueOffset));
 
     Label fpu_eq, fpu_lt, fpu_gt;
-    // Compare operands (test if unordered).
-    __ c(UN, D, f0, f2);
+    // Compare operands (test if unordered) - built into the eq test below.
     // Don't base result on status bits when a NaN is involved.

[Erik Corry, 2011/09/14 13:48:57]

Comment seems out of date.

[Paul Lind, 2011/09/15 05:49:25]

Yes, this comment was bad, as were some others nearby, and then I optimized the
code a bit as well. Better now. Thanks.

-    __ bc1t(&unordered);
-    __ nop();
-
     // Test if equal.
-    __ c(EQ, D, f0, f2);
-    __ bc1t(&fpu_eq);
-    __ nop();
+    __ BranchF(&fpu_eq, &unordered, eq, f0, f2);
 
     // Test if unordered or less (unordered case is already handled).
-    __ c(ULT, D, f0, f2);
-    __ bc1t(&fpu_lt);
-    __ nop();
-
     // Otherwise it's greater.
-    __ bc1f(&fpu_gt);
-    __ nop();
+    __ BranchF(&fpu_lt, NULL, lt, f0, f2, USE_DELAY_SLOT);
+    __ BranchF(&fpu_gt, NULL, gt, f0, f2, USE_DELAY_SLOT);
 
     // Return a result of -1, 0, or 1.
     __ bind(&fpu_eq);