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

src/compiler/simplified-lowering.cc

 // Copyright 2014 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/compiler/simplified-lowering.h"
 
 #include <limits>
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 822 matching lines @@
       case IrOpcode::kNumberShiftRightLogical: {
         VisitBinop(node, UseInfo::TruncatingWord32(),
                    UseInfo::TruncatingWord32(), kMachUint32);
         if (lower()) lowering->DoShift(node, lowering->machine()->Word32Shr());
         break;
       }
       case IrOpcode::kNumberToInt32: {
         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())) {
+        } 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 if ((in & kTypeMask) == kTypeInt32 ||
-                   (in & kRepMask) == kRepWord32) {
-          // Just change representation if necessary.
-          VisitUnop(node, UseInfo::TruncatingWord32(), kTypeInt32 | kRepWord32);
-          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;
       }
       case IrOpcode::kNumberToUint32: {
         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())) {
+        } 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 if ((in & kTypeMask) == kTypeUint32 ||
-                   (in & kRepMask) == kRepWord32) {
-          // Just change representation if necessary.
-          VisitUnop(node, UseInfo::TruncatingWord32(),
-                    kTypeUint32 | kRepWord32);
-          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;
       }
       case IrOpcode::kNumberIsHoleNaN: {
         VisitUnop(node, UseInfo::Float64(), kMachBool);
         if (lower()) {
           // NumberIsHoleNaN(x) => Word32Equal(Float64ExtractLowWord32(x),
           //                                   #HoleNaNLower32)
           node->ReplaceInput(0,
                              jsgraph_->graph()->NewNode(
@@ skipping 791 matching lines @@
   ReplaceEffectUses(node, comparison);
   node->ReplaceInput(0, comparison);
   node->ReplaceInput(1, jsgraph()->SmiConstant(EQUAL));
   node->TrimInputCount(2);
   NodeProperties::ChangeOp(node, machine()->IntLessThanOrEqual());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8