Use Representation::Integer32() for smi types on 32-bit-tagged systems.

BUG=
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/187353005

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19684 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/hydrogen-instructions.cc

@@ -2605,8 +2605,8 @@ HConstant::HConstant(ExternalReference reference)
 
 void HConstant::Initialize(Representation r) {
   if (r.IsNone()) {
-    if (has_smi_value_ && SmiValuesAre31Bits()) {
-      r = Representation::Smi();
+    if (has_smi_value_) {
+      r = Representation::FromType(Type::Smi());
     } else if (has_int32_value_) {
       r = Representation::Integer32();
     } else if (has_double_value_) {

src/hydrogen.cc

@@ -8741,7 +8741,7 @@ HInstruction* HOptimizedGraphBuilder::BuildIncrement(
   // The input to the count operation is on top of the expression stack.
   Representation rep = Representation::FromType(expr->type());
   if (rep.IsNone() || rep.IsTagged()) {
-    rep = Representation::Smi();
+    rep = Representation::FromType(Type::Smi());
   }
 
   if (returns_original_input) {
@@ -8991,14 +8991,8 @@ bool CanBeZero(HValue* right) {
 
 HValue* HGraphBuilder::EnforceNumberType(HValue* number,
                                          Type* expected) {
-  if (expected->Is(Type::Smi())) {
-    return AddUncasted<HForceRepresentation>(number, Representation::Smi());
-  }
-  if (expected->Is(Type::Signed32())) {
-    return AddUncasted<HForceRepresentation>(number,
-                                             Representation::Integer32());
-  }
-  return number;
+  return AddUncasted<HForceRepresentation>(
+      number, Representation::FromType(expected));
 }
 
 

src/types.cc

@@ -568,7 +568,8 @@ typename TypeImpl<Config>::TypeHandle TypeImpl<Config>::Convert(
 // TODO(rossberg): this does not belong here.
 Representation Representation::FromType(Type* type) {
   if (type->Is(Type::None())) return Representation::None();
-  if (type->Is(Type::Smi())) return Representation::Smi();
+  if (type->Is(Type::Smi())) return SmiValuesAre31Bits()
+      ? Representation::Smi() : Representation::Integer32();
   if (type->Is(Type::Signed32())) return Representation::Integer32();
   if (type->Is(Type::Number())) return Representation::Double();
   return Representation::Tagged();

test/mjsunit/regress/regress-crbug-349079.js

@@ -21,3 +21,16 @@ crash();
 crash();
 %OptimizeFunctionOnNextCall(crash);
 crash();
+
+function f() {
+  var v1 = 0;
+  var v2 = -0;
+  var t = v2++;
+  v2++;
+  return Math.max(v2++, v1++);
+}
+
+f();
+f();
+%OptimizeFunctionOnNextCall(f);
+f();