Give more precise types to some Math functions.

src/compiler/js-typed-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/access-builder.h"
 #include "src/compiler/graph-inl.h"
 #include "src/compiler/js-builtin-reducer.h"
 #include "src/compiler/js-typed-lowering.h"
 #include "src/compiler/node-aux-data-inl.h"
 #include "src/compiler/node-properties-inl.h"
@@ skipping 145 matching lines @@
   Node* ConvertToNumber(Node* node) {
     // Avoid introducing too many eager ToNumber() operations.
     Reduction reduced = lowering_->ReduceJSToNumberInput(node);
     if (reduced.Changed()) return reduced.replacement();
     Node* n = graph()->NewNode(javascript()->ToNumber(), node, context(),
                                effect(), control());
     update_effect(n);
     return n;
   }
 
-  // Try to narrowing a double or number operation to an Int32 operation.
+  // Try narrowing a double or number operation to an Int32 operation.
   bool TryNarrowingToI32(Type* type, Node* node) {
     switch (node->opcode()) {
       case IrOpcode::kFloat64Add:
       case IrOpcode::kNumberAdd: {
         JSBinopReduction r(lowering_, node);
         if (r.BothInputsAre(Type::Integral32())) {
           node->set_op(lowering_->machine()->Int32Add());
           // TODO(titzer): narrow bounds instead of overwriting.
           NodeProperties::SetBounds(node, Bounds(type));
           return true;
@@ skipping 389 matching lines @@
 
 
 Reduction JSTypedLowering::ReduceJSStoreProperty(Node* node) {
   Node* key = NodeProperties::GetValueInput(node, 1);
   Node* base = NodeProperties::GetValueInput(node, 0);
   Node* value = NodeProperties::GetValueInput(node, 2);
   Type* key_type = NodeProperties::GetBounds(key).upper;
   Type* base_type = NodeProperties::GetBounds(base).upper;
   // TODO(mstarzinger): This lowering is not correct if:
   //   a) The typed array turns external (i.e. MaterializeArrayBuffer)
-  //   b) The typed array or it's buffer is neutered.
+  //   b) The typed array or its buffer is neutered.
   if (key_type->Is(Type::Integral32()) && base_type->IsConstant() &&
       base_type->AsConstant()->Value()->IsJSTypedArray()) {
     // JSStoreProperty(typed-array, int32, value)
     JSTypedArray* array = JSTypedArray::cast(*base_type->AsConstant()->Value());
     ElementsKind elements_kind = array->map()->elements_kind();
     ExternalArrayType type = array->type();
     uint32_t length;
     CHECK(array->length()->ToUint32(&length));
     ElementAccess element_access;
     Node* elements = graph()->NewNode(
@@ skipping 114 matching lines @@
       return JSBuiltinReducer(jsgraph()).Reduce(node);
     default:
       break;
   }
   return NoChange();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8