[turbofan] Simplify NumberTo(U)Int32 handling in representation inference.

Review URL: https://codereview.chromium.org/1461963002

Cr-Commit-Position: refs/heads/master@{#32113}

src/compiler/representation-change.h

@@ -211,16 +211,8 @@ class RepresentationChanger {
     return jsgraph()->graph()->NewNode(op, node);
   }
 
-  Node* MakeInt32Constant(double value) {
-    if (value < 0) {
-      DCHECK(IsInt32Double(value));
-      int32_t iv = static_cast<int32_t>(value);
-      return jsgraph()->Int32Constant(iv);
-    } else {
-      DCHECK(IsUint32Double(value));
-      int32_t iv = static_cast<int32_t>(static_cast<uint32_t>(value));
-      return jsgraph()->Int32Constant(iv);
-    }
+  Node* MakeTruncatedInt32Constant(double value) {
+    return jsgraph()->Int32Constant(DoubleToInt32(value));
   }
 
   Node* GetTruncatedWord32For(Node* node, MachineTypeUnion output_type) {
@@ -260,10 +252,10 @@ class RepresentationChanger {
       case IrOpcode::kInt32Constant:
         return node;  // No change necessary.
       case IrOpcode::kFloat32Constant:
-        return MakeInt32Constant(OpParameter<float>(node));
+        return MakeTruncatedInt32Constant(OpParameter<float>(node));
       case IrOpcode::kNumberConstant:
       case IrOpcode::kFloat64Constant:
-        return MakeInt32Constant(OpParameter<double>(node));
+        return MakeTruncatedInt32Constant(OpParameter<double>(node));
       default:
         break;
     }

src/compiler/simplified-lowering.cc

@@ -840,32 +840,15 @@ class RepresentationSelector {
         MachineTypeUnion use_rep = use & kRepMask;
         Node* input = node->InputAt(0);
         Type* in_upper = NodeProperties::GetType(input);
-        MachineTypeUnion in = GetInfo(input)->output;
         if (in_upper->Is(Type::Signed32())) {
           // If the input has type int32, pass through representation.
           VisitUnop(node, UseInfoFromRepresentation(use_rep),
                     kTypeInt32 | use_rep);
           if (lower()) DeferReplacement(node, node->InputAt(0));
-        } else if ((in & kTypeMask) == kTypeUint32 ||
-                   in_upper->Is(Type::Unsigned32())) {
-          // Just change representation if necessary.
-          VisitUnop(node, UseInfo::TruncatingWord32(), kTypeInt32 | kRepWord32);
-          if (lower()) DeferReplacement(node, node->InputAt(0));
-        } else if ((in & kTypeMask) == kTypeInt32 ||
-                   (in & kRepMask) == kRepWord32) {
+        } else {
           // Just change representation if necessary.
-          VisitUnop(node, UseInfo::TruncatingWord32(), kTypeInt32 | kRepWord32);
+          VisitUnop(node, UseInfo::TruncatingWord32(), kMachInt32);
           if (lower()) DeferReplacement(node, node->InputAt(0));
-        } else {
-          // Require the input in float64 format and perform truncation.
-          // TODO(turbofan): avoid a truncation with a smi check.
-          VisitUnop(node, UseInfo::Float64TruncatingToWord32(),
-                    kTypeInt32 | kRepWord32);
-          if (lower()) {
-            NodeProperties::ChangeOp(
-                node, lowering->machine()->TruncateFloat64ToInt32(
-                          TruncationMode::kJavaScript));
-          }
         }
         break;
       }
@@ -873,34 +856,15 @@ class RepresentationSelector {
         MachineTypeUnion use_rep = use & kRepMask;
         Node* input = node->InputAt(0);
         Type* in_upper = NodeProperties::GetType(input);
-        MachineTypeUnion in = GetInfo(input)->output;
         if (in_upper->Is(Type::Unsigned32())) {
           // If the input has type uint32, pass through representation.
           VisitUnop(node, UseInfoFromRepresentation(use_rep),
                     kTypeUint32 | use_rep);
           if (lower()) DeferReplacement(node, node->InputAt(0));
-        } else if ((in & kTypeMask) == kTypeInt32 ||
-                   in_upper->Is(Type::Signed32())) {
-          // Just change representation if necessary.
-          VisitUnop(node, UseInfo::TruncatingWord32(),
-                    kTypeUint32 | kRepWord32);
-          if (lower()) DeferReplacement(node, node->InputAt(0));
-        } else if ((in & kTypeMask) == kTypeUint32 ||
-                   (in & kRepMask) == kRepWord32) {
+        } else {
           // Just change representation if necessary.
-          VisitUnop(node, UseInfo::TruncatingWord32(),
-                    kTypeUint32 | kRepWord32);
+          VisitUnop(node, UseInfo::TruncatingWord32(), kMachUint32);
           if (lower()) DeferReplacement(node, node->InputAt(0));
-        } else {
-          // Require the input in float64 format and perform truncation.
-          // TODO(turbofan): avoid a truncation with a smi check.
-          VisitUnop(node, UseInfo::Float64TruncatingToWord32(),
-                    kTypeUint32 | kRepWord32);
-          if (lower()) {
-            NodeProperties::ChangeOp(
-                node, lowering->machine()->TruncateFloat64ToInt32(
-                          TruncationMode::kJavaScript));
-          }
         }
         break;
       }