Changeset 34555 in webkit for trunk/JavaScriptCore/VM/CodeGenerator.h

Timestamp:

Jun 14, 2008, 10:24:21 PM (17 years ago)

Author:

[email protected]

Message:

2008-06-14 Cameron Zwarich <​[email protected]>

Reviewed by Maciej.

Make code generation not use a temporary for the left-hand side of an
expression if the right-hand side is a local variable.

• VM/CodeGenerator.cpp: (KJS::CodeGenerator::isLocal):
• VM/CodeGenerator.h: (KJS::CodeGenerator::leftHandSideNeedsCopy): (KJS::CodeGenerator::emitNodeForLeftHandSide):
• kjs/nodes.cpp: (KJS::ResolveNode::isPure): (KJS::BracketAccessorNode::emitCode): (KJS::AddNode::emitCode): (KJS::SubNode::emitCode): (KJS::ReadModifyResolveNode::emitCode): (KJS::AssignDotNode::emitCode): (KJS::ReadModifyDotNode::emitCode): (KJS::AssignBracketNode::emitCode): (KJS::ReadModifyBracketNode::emitCode):
• kjs/nodes.h: (KJS::ExpressionNode::): (KJS::BooleanNode::): (KJS::NumberNode::): (KJS::StringNode::):

File:

• trunk/JavaScriptCore/VM/CodeGenerator.h (modified) (2 diffs)

trunk/JavaScriptCore/VM/CodeGenerator.h

@@ -109 +109 @@
         RegisterID* thisRegister() { return &m_thisRegister; }
 
+        bool isLocal(const Identifier&);
         bool isLocalConstant(const Identifier&);
 
@@ -172 +173 @@
         }
 
-        ALWAYS_INLINE bool leftHandSideNeedsCopy(bool rightHasAssignments, bool rightIsConstant)
-        {
-            return (m_codeType != FunctionCode || m_codeBlock->needsFullScopeChain || rightHasAssignments) && !rightIsConstant;
-        }
-
-        ALWAYS_INLINE PassRefPtr<RegisterID> emitNodeForLeftHandSide(ExpressionNode* n, bool rightHasAssignments, bool rightIsConstant)
-        {
-            if (leftHandSideNeedsCopy(rightHasAssignments, rightIsConstant)) {
+        ALWAYS_INLINE bool leftHandSideNeedsCopy(bool rightHasAssignments, bool rightIsPure)
+        {
+            return (m_codeType != FunctionCode || m_codeBlock->needsFullScopeChain || rightHasAssignments) && !rightIsPure;
+        }
+
+        ALWAYS_INLINE PassRefPtr<RegisterID> emitNodeForLeftHandSide(ExpressionNode* n, bool rightHasAssignments, bool rightIsPure)
+        {
+            if (leftHandSideNeedsCopy(rightHasAssignments, rightIsPure)) {
                 PassRefPtr<RegisterID> dst = newTemporary();
                 emitNode(dst.get(), n);