Fixed deopt reasons in TaggedToI.

src/ia32/lithium-codegen-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 4745 matching lines @@
     __ cmp(input_reg, factory()->true_value());
     __ j(not_equal, &check_false, Label::kNear);
     __ Move(input_reg, Immediate(1));
     __ jmp(done);
 
     __ bind(&check_false);
     __ cmp(input_reg, factory()->false_value());
     __ RecordComment("Deferred TaggedToI: cannot truncate");
     DeoptimizeIf(not_equal, instr->environment());
     __ Move(input_reg, Immediate(0));
+    __ jmp(done);

[Jakob Kummerow, 2014/09/17 09:22:35]

As discussed, we don't need this jump (as it would jump to the very next
instruction, which is the jump to the deferred code's exit label).

   } else {
-    Label bailout;
-    XMMRegister scratch = (instr->temp() != NULL)
-        ? ToDoubleRegister(instr->temp())
-        : no_xmm_reg;
-    __ TaggedToI(input_reg, input_reg, scratch,
-                 instr->hydrogen()->GetMinusZeroMode(), &bailout);
+    XMMRegister scratch = ToDoubleRegister(instr->temp());
+    DCHECK(!scratch.is(xmm0));
+    __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
+           isolate()->factory()->heap_number_map());
+    __ RecordComment("Deferred TaggedToI: not a heap number");
+    DeoptimizeIf(not_equal, instr->environment());
+    __ movsd(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
+    __ cvttsd2si(input_reg, Operand(xmm0));
+    __ Cvtsi2sd(scratch, Operand(input_reg));
+    __ ucomisd(xmm0, scratch);
+    __ RecordComment("Deferred TaggedToI: lost precision");
+    DeoptimizeIf(not_equal, instr->environment());
+    __ RecordComment("Deferred TaggedToI: NaN");
+    DeoptimizeIf(parity_even, instr->environment());
+    if (instr->hydrogen()->GetMinusZeroMode() == FAIL_ON_MINUS_ZERO) {
+      __ test(input_reg, Operand(input_reg));
+      __ j(not_zero, done);
+      __ movmskpd(input_reg, xmm0);
+      __ and_(input_reg, 1);
+      __ RecordComment("Deferred TaggedToI: minus zero");
+      DeoptimizeIf(not_zero, instr->environment());
+    }
     __ jmp(done);

[Jakob Kummerow, 2014/09/17 09:22:35]

This can go too (see above).

-    __ bind(&bailout);
-    DeoptimizeIf(no_condition, instr->environment());
   }
 }
 
 
 void LCodeGen::DoTaggedToI(LTaggedToI* instr) {
   class DeferredTaggedToI FINAL : public LDeferredCode {
    public:
     DeferredTaggedToI(LCodeGen* codegen, LTaggedToI* instr)
         : LDeferredCode(codegen), instr_(instr) { }
     virtual void Generate() OVERRIDE {
@@ skipping 912 matching lines @@
   CallRuntime(Runtime::kPushBlockContext, 2, instr);
   RecordSafepoint(Safepoint::kNoLazyDeopt);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32