Lattice-based representation inference, powered by left/right specific type feedback for BinaryOps …

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 6e86d920a26fcea1546ddf6e6a56254b7b59d4e1..3e19c39ba24de278a78f128739f899402e46735a 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -302,7 +302,30 @@ bool LCodeGen::GenerateBody() {
     }
 
     if (emit_instructions) {
-      Comment(";;; @%d: %s.", current_instruction_, instr->Mnemonic());
+      if (FLAG_code_comments) {
+        HValue* hydrogen = instr->hydrogen_value();
+        if (hydrogen != NULL) {
+          if (hydrogen->IsChange()) {
+            HValue* changed_value = HChange::cast(hydrogen)->value();
+            int use_id = 0;
+            const char* use_mnemo = "dead";
+            if (hydrogen->UseCount() >= 1) {
+              HValue* use_value = hydrogen->uses().value();
+              use_id = use_value->id();
+              use_mnemo = use_value->Mnemonic();
+            }
+            Comment(";;; @%d: %s. <of #%d %s for #%d %s>",
+                    current_instruction_, instr->Mnemonic(),
+                    changed_value->id(), changed_value->Mnemonic(),
+                    use_id, use_mnemo);
+          } else {
+            Comment(";;; @%d: %s. <#%d>", current_instruction_,
+                    instr->Mnemonic(), hydrogen->id());
+          }
+        } else {
+          Comment(";;; @%d: %s.", current_instruction_, instr->Mnemonic());
+        }
+      }
       instr->CompileToNative(this);
     }
   }
@@ -4411,6 +4434,7 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
     // Check for undefined. Undefined is converted to zero for truncating
     // conversions.
     __ cmp(input_reg, factory()->undefined_value());
+    __ RecordComment("Deferred TaggedToI: cannot truncate");
     DeoptimizeIf(not_equal, instr->environment());
     __ mov(input_reg, 0);
     __ jmp(&done, Label::kNear);
@@ -4431,6 +4455,7 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
       __ j(less, &convert, Label::kNear);
       // Pop FPU stack before deoptimizing.
       __ fstp(0);
+      __ RecordComment("Deferred TaggedToI: exponent too big");
       DeoptimizeIf(no_condition, instr->environment());
 
       // Reserve space for 64 bit answer.
@@ -4456,6 +4481,7 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
     }
   } else {
     // Deoptimize if we don't have a heap number.
+    __ RecordComment("Deferred TaggedToI: not a heap number");
     DeoptimizeIf(not_equal, instr->environment());
 
     XMMRegister xmm_temp = ToDoubleRegister(instr->temp());
@@ -4463,13 +4489,16 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
     __ cvttsd2si(input_reg, Operand(xmm0));
     __ cvtsi2sd(xmm_temp, Operand(input_reg));
     __ ucomisd(xmm0, xmm_temp);
+    __ RecordComment("Deferred TaggedToI: lost precision");
     DeoptimizeIf(not_equal, instr->environment());
+    __ RecordComment("Deferred TaggedToI: NaN");
     DeoptimizeIf(parity_even, instr->environment());  // NaN.
     if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
       __ 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());
     }
   }