--- /dev/null
+/*
+ * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
+ * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ * its contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef BytecodeGenerator_h
+#define BytecodeGenerator_h
+
+#include "CodeBlock.h"
+#include "HashTraits.h"
+#include "Instruction.h"
+#include "Label.h"
+#include "LabelScope.h"
+#include "Interpreter.h"
+#include "RegisterID.h"
+#include "SegmentedVector.h"
+#include "SymbolTable.h"
+#include "Debugger.h"
+#include "Nodes.h"
+#include <wtf/PassRefPtr.h>
+#include <wtf/Vector.h>
+
+namespace JSC {
+
+ class Identifier;
+ class ScopeChain;
+ class ScopeNode;
+
+ struct FinallyContext {
+ Label* finallyAddr;
+ RegisterID* retAddrDst;
+ };
+
+ struct ControlFlowContext {
+ bool isFinallyBlock;
+ FinallyContext finallyContext;
+ };
+
+ class BytecodeGenerator {
+ public:
+ typedef DeclarationStacks::VarStack VarStack;
+ typedef DeclarationStacks::FunctionStack FunctionStack;
+
+ static void setDumpsGeneratedCode(bool dumpsGeneratedCode);
+ static bool dumpsGeneratedCode();
+
+ BytecodeGenerator(ProgramNode*, const Debugger*, const ScopeChain&, SymbolTable*, ProgramCodeBlock*);
+ BytecodeGenerator(FunctionBodyNode*, const Debugger*, const ScopeChain&, SymbolTable*, CodeBlock*);
+ BytecodeGenerator(EvalNode*, const Debugger*, const ScopeChain&, SymbolTable*, EvalCodeBlock*);
+
+ JSGlobalData* globalData() const { return m_globalData; }
+ const CommonIdentifiers& propertyNames() const { return *m_globalData->propertyNames; }
+
+ void generate();
+
+ // Returns the register corresponding to a local variable, or 0 if no
+ // such register exists. Registers returned by registerFor do not
+ // require explicit reference counting.
+ RegisterID* registerFor(const Identifier&);
+
+ // Behaves as registerFor does, but ignores dynamic scope as
+ // dynamic scope should not interfere with const initialisation
+ RegisterID* constRegisterFor(const Identifier&);
+
+ // Searches the scope chain in an attempt to statically locate the requested
+ // property. Returns false if for any reason the property cannot be safely
+ // optimised at all. Otherwise it will return the index and depth of the
+ // VariableObject that defines the property. If the property cannot be found
+ // statically, depth will contain the depth of the scope chain where dynamic
+ // lookup must begin.
+ //
+ // NB: depth does _not_ include the local scope. eg. a depth of 0 refers
+ // to the scope containing this codeblock.
+ bool findScopedProperty(const Identifier&, int& index, size_t& depth, bool forWriting, JSObject*& globalObject);
+
+ // Returns the register storing "this"
+ RegisterID* thisRegister() { return &m_thisRegister; }
+
+ bool isLocal(const Identifier&);
+ bool isLocalConstant(const Identifier&);
+
+ // Returns the next available temporary register. Registers returned by
+ // newTemporary require a modified form of reference counting: any
+ // register with a refcount of 0 is considered "available", meaning that
+ // the next instruction may overwrite it.
+ RegisterID* newTemporary();
+
+ RegisterID* highestUsedRegister();
+
+ // The same as newTemporary(), but this function returns "suggestion" if
+ // "suggestion" is a temporary. This function is helpful in situations
+ // where you've put "suggestion" in a RefPtr, but you'd like to allow
+ // the next instruction to overwrite it anyway.
+ RegisterID* newTemporaryOr(RegisterID* suggestion) { return suggestion->isTemporary() ? suggestion : newTemporary(); }
+
+ // Functions for handling of dst register
+
+ RegisterID* ignoredResult() { return &m_ignoredResultRegister; }
+
+ // Returns a place to write intermediate values of an operation
+ // which reuses dst if it is safe to do so.
+ RegisterID* tempDestination(RegisterID* dst)
+ {
+ return (dst && dst != ignoredResult() && dst->isTemporary()) ? dst : newTemporary();
+ }
+
+ // Returns the place to write the final output of an operation.
+ RegisterID* finalDestination(RegisterID* originalDst, RegisterID* tempDst = 0)
+ {
+ if (originalDst && originalDst != ignoredResult())
+ return originalDst;
+ ASSERT(tempDst != ignoredResult());
+ if (tempDst && tempDst->isTemporary())
+ return tempDst;
+ return newTemporary();
+ }
+
+ RegisterID* destinationForAssignResult(RegisterID* dst)
+ {
+ if (dst && dst != ignoredResult() && m_codeBlock->needsFullScopeChain())
+ return dst->isTemporary() ? dst : newTemporary();
+ return 0;
+ }
+
+ // Moves src to dst if dst is not null and is different from src, otherwise just returns src.
+ RegisterID* moveToDestinationIfNeeded(RegisterID* dst, RegisterID* src)
+ {
+ return dst == ignoredResult() ? 0 : (dst && dst != src) ? emitMove(dst, src) : src;
+ }
+
+ PassRefPtr<LabelScope> newLabelScope(LabelScope::Type, const Identifier* = 0);
+ PassRefPtr<Label> newLabel();
+
+ // The emitNode functions are just syntactic sugar for calling
+ // Node::emitCode. These functions accept a 0 for the register,
+ // meaning that the node should allocate a register, or ignoredResult(),
+ // meaning that the node need not put the result in a register.
+ // Other emit functions do not accept 0 or ignoredResult().
+ RegisterID* emitNode(RegisterID* dst, Node* n)
+ {
+ // Node::emitCode assumes that dst, if provided, is either a local or a referenced temporary.
+ ASSERT(!dst || dst == ignoredResult() || !dst->isTemporary() || dst->refCount());
+ if (!m_codeBlock->numberOfLineInfos() || m_codeBlock->lastLineInfo().lineNumber != n->lineNo()) {
+ LineInfo info = { instructions().size(), n->lineNo() };
+ m_codeBlock->addLineInfo(info);
+ }
+ if (m_emitNodeDepth >= s_maxEmitNodeDepth)
+ return emitThrowExpressionTooDeepException();
+ ++m_emitNodeDepth;
+ RegisterID* r = n->emitBytecode(*this, dst);
+ --m_emitNodeDepth;
+ return r;
+ }
+
+ RegisterID* emitNode(Node* n)
+ {
+ return emitNode(0, n);
+ }
+
+ void emitExpressionInfo(unsigned divot, unsigned startOffset, unsigned endOffset)
+ {
+ divot -= m_codeBlock->sourceOffset();
+ if (divot > ExpressionRangeInfo::MaxDivot) {
+ // Overflow has occurred, we can only give line number info for errors for this region
+ divot = 0;
+ startOffset = 0;
+ endOffset = 0;
+ } else if (startOffset > ExpressionRangeInfo::MaxOffset) {
+ // If the start offset is out of bounds we clear both offsets
+ // so we only get the divot marker. Error message will have to be reduced
+ // to line and column number.
+ startOffset = 0;
+ endOffset = 0;
+ } else if (endOffset > ExpressionRangeInfo::MaxOffset) {
+ // The end offset is only used for additional context, and is much more likely
+ // to overflow (eg. function call arguments) so we are willing to drop it without
+ // dropping the rest of the range.
+ endOffset = 0;
+ }
+
+ ExpressionRangeInfo info;
+ info.instructionOffset = instructions().size();
+ info.divotPoint = divot;
+ info.startOffset = startOffset;
+ info.endOffset = endOffset;
+ m_codeBlock->addExpressionInfo(info);
+ }
+
+ void emitGetByIdExceptionInfo(OpcodeID opcodeID)
+ {
+ // Only op_construct and op_instanceof need exception info for
+ // a preceding op_get_by_id.
+ ASSERT(opcodeID == op_construct || opcodeID == op_instanceof);
+ GetByIdExceptionInfo info;
+ info.bytecodeOffset = instructions().size();
+ info.isOpConstruct = (opcodeID == op_construct);
+ m_codeBlock->addGetByIdExceptionInfo(info);
+ }
+
+ 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);
+ return dst;
+ }
+
+ return PassRefPtr<RegisterID>(emitNode(n));
+ }
+
+ RegisterID* emitLoad(RegisterID* dst, bool);
+ RegisterID* emitLoad(RegisterID* dst, double);
+ RegisterID* emitLoad(RegisterID* dst, const Identifier&);
+ RegisterID* emitLoad(RegisterID* dst, JSValuePtr);
+ RegisterID* emitUnexpectedLoad(RegisterID* dst, bool);
+ RegisterID* emitUnexpectedLoad(RegisterID* dst, double);
+
+ RegisterID* emitUnaryOp(OpcodeID, RegisterID* dst, RegisterID* src);
+ RegisterID* emitBinaryOp(OpcodeID, RegisterID* dst, RegisterID* src1, RegisterID* src2, OperandTypes);
+ RegisterID* emitEqualityOp(OpcodeID, RegisterID* dst, RegisterID* src1, RegisterID* src2);
+ RegisterID* emitUnaryNoDstOp(OpcodeID, RegisterID* src);
+
+ RegisterID* emitNewObject(RegisterID* dst);
+ RegisterID* emitNewArray(RegisterID* dst, ElementNode*); // stops at first elision
+
+ RegisterID* emitNewFunction(RegisterID* dst, FuncDeclNode* func);
+ RegisterID* emitNewFunctionExpression(RegisterID* dst, FuncExprNode* func);
+ RegisterID* emitNewRegExp(RegisterID* dst, RegExp* regExp);
+
+ RegisterID* emitMove(RegisterID* dst, RegisterID* src);
+
+ RegisterID* emitToJSNumber(RegisterID* dst, RegisterID* src) { return emitUnaryOp(op_to_jsnumber, dst, src); }
+ RegisterID* emitPreInc(RegisterID* srcDst);
+ RegisterID* emitPreDec(RegisterID* srcDst);
+ RegisterID* emitPostInc(RegisterID* dst, RegisterID* srcDst);
+ RegisterID* emitPostDec(RegisterID* dst, RegisterID* srcDst);
+
+ RegisterID* emitInstanceOf(RegisterID* dst, RegisterID* value, RegisterID* base, RegisterID* basePrototype);
+ RegisterID* emitTypeOf(RegisterID* dst, RegisterID* src) { return emitUnaryOp(op_typeof, dst, src); }
+ RegisterID* emitIn(RegisterID* dst, RegisterID* property, RegisterID* base) { return emitBinaryOp(op_in, dst, property, base, OperandTypes()); }
+
+ RegisterID* emitResolve(RegisterID* dst, const Identifier& property);
+ RegisterID* emitGetScopedVar(RegisterID* dst, size_t skip, int index, JSValuePtr globalObject);
+ RegisterID* emitPutScopedVar(size_t skip, int index, RegisterID* value, JSValuePtr globalObject);
+
+ RegisterID* emitResolveBase(RegisterID* dst, const Identifier& property);
+ RegisterID* emitResolveWithBase(RegisterID* baseDst, RegisterID* propDst, const Identifier& property);
+ RegisterID* emitResolveFunction(RegisterID* baseDst, RegisterID* funcDst, const Identifier& property);
+
+ RegisterID* emitGetById(RegisterID* dst, RegisterID* base, const Identifier& property);
+ RegisterID* emitPutById(RegisterID* base, const Identifier& property, RegisterID* value);
+ RegisterID* emitDeleteById(RegisterID* dst, RegisterID* base, const Identifier&);
+ RegisterID* emitGetByVal(RegisterID* dst, RegisterID* base, RegisterID* property);
+ RegisterID* emitPutByVal(RegisterID* base, RegisterID* property, RegisterID* value);
+ RegisterID* emitDeleteByVal(RegisterID* dst, RegisterID* base, RegisterID* property);
+ RegisterID* emitPutByIndex(RegisterID* base, unsigned index, RegisterID* value);
+ RegisterID* emitPutGetter(RegisterID* base, const Identifier& property, RegisterID* value);
+ RegisterID* emitPutSetter(RegisterID* base, const Identifier& property, RegisterID* value);
+
+ RegisterID* emitCall(RegisterID* dst, RegisterID* func, RegisterID* thisRegister, ArgumentsNode*, unsigned divot, unsigned startOffset, unsigned endOffset);
+ RegisterID* emitCallEval(RegisterID* dst, RegisterID* func, RegisterID* thisRegister, ArgumentsNode*, unsigned divot, unsigned startOffset, unsigned endOffset);
+
+ RegisterID* emitReturn(RegisterID* src);
+ RegisterID* emitEnd(RegisterID* src) { return emitUnaryNoDstOp(op_end, src); }
+
+ RegisterID* emitConstruct(RegisterID* dst, RegisterID* func, ArgumentsNode*, unsigned divot, unsigned startOffset, unsigned endOffset);
+
+ PassRefPtr<Label> emitLabel(Label*);
+ PassRefPtr<Label> emitJump(Label* target);
+ PassRefPtr<Label> emitJumpIfTrue(RegisterID* cond, Label* target);
+ PassRefPtr<Label> emitJumpIfFalse(RegisterID* cond, Label* target);
+ PassRefPtr<Label> emitJumpScopes(Label* target, int targetScopeDepth);
+
+ PassRefPtr<Label> emitJumpSubroutine(RegisterID* retAddrDst, Label*);
+ void emitSubroutineReturn(RegisterID* retAddrSrc);
+
+ RegisterID* emitGetPropertyNames(RegisterID* dst, RegisterID* base) { return emitUnaryOp(op_get_pnames, dst, base); }
+ RegisterID* emitNextPropertyName(RegisterID* dst, RegisterID* iter, Label* target);
+
+ RegisterID* emitCatch(RegisterID*, Label* start, Label* end);
+ void emitThrow(RegisterID* exc) { emitUnaryNoDstOp(op_throw, exc); }
+ RegisterID* emitNewError(RegisterID* dst, ErrorType type, JSValuePtr message);
+ void emitPushNewScope(RegisterID* dst, Identifier& property, RegisterID* value);
+
+ RegisterID* emitPushScope(RegisterID* scope);
+ void emitPopScope();
+
+ void emitDebugHook(DebugHookID, int firstLine, int lastLine);
+
+ int scopeDepth() { return m_dynamicScopeDepth + m_finallyDepth; }
+ bool hasFinaliser() { return m_finallyDepth != 0; }
+
+ void pushFinallyContext(Label* target, RegisterID* returnAddrDst);
+ void popFinallyContext();
+
+ LabelScope* breakTarget(const Identifier&);
+ LabelScope* continueTarget(const Identifier&);
+
+ void beginSwitch(RegisterID*, SwitchInfo::SwitchType);
+ void endSwitch(uint32_t clauseCount, RefPtr<Label>*, ExpressionNode**, Label* defaultLabel, int32_t min, int32_t range);
+
+ CodeType codeType() const { return m_codeType; }
+
+ void setRegeneratingForExceptionInfo(CodeBlock* originalCodeBlock)
+ {
+ m_regeneratingForExceptionInfo = true;
+ m_codeBlockBeingRegeneratedFrom = originalCodeBlock;
+ }
+
+ private:
+ void emitOpcode(OpcodeID);
+ void retrieveLastBinaryOp(int& dstIndex, int& src1Index, int& src2Index);
+ void retrieveLastUnaryOp(int& dstIndex, int& srcIndex);
+ void rewindBinaryOp();
+ void rewindUnaryOp();
+
+ PassRefPtr<Label> emitComplexJumpScopes(Label* target, ControlFlowContext* topScope, ControlFlowContext* bottomScope);
+
+ struct JSValueHashTraits : HashTraits<JSValueEncodedAsPointer*> {
+ static void constructDeletedValue(JSValueEncodedAsPointer*& slot) { slot = JSValuePtr::encode(jsImpossibleValue()); }
+ static bool isDeletedValue(JSValueEncodedAsPointer* value) { return value == JSValuePtr::encode(jsImpossibleValue()); }
+ };
+
+ typedef HashMap<JSValueEncodedAsPointer*, unsigned, PtrHash<JSValueEncodedAsPointer*>, JSValueHashTraits> JSValueMap;
+
+ struct IdentifierMapIndexHashTraits {
+ typedef int TraitType;
+ typedef IdentifierMapIndexHashTraits StorageTraits;
+ static int emptyValue() { return std::numeric_limits<int>::max(); }
+ static const bool emptyValueIsZero = false;
+ static const bool needsDestruction = false;
+ static const bool needsRef = false;
+ };
+
+ typedef HashMap<RefPtr<UString::Rep>, int, IdentifierRepHash, HashTraits<RefPtr<UString::Rep> >, IdentifierMapIndexHashTraits> IdentifierMap;
+ typedef HashMap<double, JSValuePtr> NumberMap;
+ typedef HashMap<UString::Rep*, JSString*, IdentifierRepHash> IdentifierStringMap;
+
+ RegisterID* emitCall(OpcodeID, RegisterID* dst, RegisterID* func, RegisterID* thisRegister, ArgumentsNode*, unsigned divot, unsigned startOffset, unsigned endOffset);
+
+ RegisterID* newRegister();
+
+ // Returns the RegisterID corresponding to ident.
+ RegisterID* addVar(const Identifier& ident, bool isConstant)
+ {
+ RegisterID* local;
+ addVar(ident, isConstant, local);
+ return local;
+ }
+ // Returns true if a new RegisterID was added, false if a pre-existing RegisterID was re-used.
+ bool addVar(const Identifier&, bool isConstant, RegisterID*&);
+
+ // Returns the RegisterID corresponding to ident.
+ RegisterID* addGlobalVar(const Identifier& ident, bool isConstant)
+ {
+ RegisterID* local;
+ addGlobalVar(ident, isConstant, local);
+ return local;
+ }
+ // Returns true if a new RegisterID was added, false if a pre-existing RegisterID was re-used.
+ bool addGlobalVar(const Identifier&, bool isConstant, RegisterID*&);
+
+ RegisterID* addParameter(const Identifier&);
+
+ void allocateConstants(size_t);
+
+ RegisterID& registerFor(int index)
+ {
+ if (index >= 0)
+ return m_calleeRegisters[index];
+
+ if (index == RegisterFile::OptionalCalleeArguments)
+ return m_argumentsRegister;
+
+ if (m_parameters.size()) {
+ ASSERT(!m_globals.size());
+ return m_parameters[index + m_parameters.size() + RegisterFile::CallFrameHeaderSize];
+ }
+
+ return m_globals[-index - 1];
+ }
+
+ unsigned addConstant(FuncDeclNode*);
+ unsigned addConstant(FuncExprNode*);
+ unsigned addConstant(const Identifier&);
+ RegisterID* addConstant(JSValuePtr);
+ unsigned addUnexpectedConstant(JSValuePtr);
+ unsigned addRegExp(RegExp*);
+
+ Vector<Instruction>& instructions() { return m_codeBlock->instructions(); }
+ SymbolTable& symbolTable() { return *m_symbolTable; }
+
+ bool shouldOptimizeLocals() { return (m_codeType != EvalCode) && !m_dynamicScopeDepth; }
+ bool canOptimizeNonLocals() { return (m_codeType == FunctionCode) && !m_dynamicScopeDepth && !m_codeBlock->usesEval(); }
+
+ RegisterID* emitThrowExpressionTooDeepException();
+
+ bool m_shouldEmitDebugHooks;
+ bool m_shouldEmitProfileHooks;
+
+ const ScopeChain* m_scopeChain;
+ SymbolTable* m_symbolTable;
+
+ ScopeNode* m_scopeNode;
+ CodeBlock* m_codeBlock;
+
+ HashSet<RefPtr<UString::Rep>, IdentifierRepHash> m_functions;
+ RegisterID m_ignoredResultRegister;
+ RegisterID m_thisRegister;
+ RegisterID m_argumentsRegister;
+ int m_activationRegisterIndex;
+ SegmentedVector<RegisterID, 512> m_calleeRegisters;
+ SegmentedVector<RegisterID, 512> m_parameters;
+ SegmentedVector<RegisterID, 512> m_globals;
+ SegmentedVector<LabelScope, 256> m_labelScopes;
+ SegmentedVector<Label, 256> m_labels;
+ RefPtr<RegisterID> m_lastConstant;
+ int m_finallyDepth;
+ int m_dynamicScopeDepth;
+ int m_baseScopeDepth;
+ CodeType m_codeType;
+
+ Vector<ControlFlowContext> m_scopeContextStack;
+ Vector<SwitchInfo> m_switchContextStack;
+
+ int m_nextGlobalIndex;
+ int m_nextParameterIndex;
+ int m_nextConstantIndex;
+
+ int m_globalVarStorageOffset;
+
+ // Constant pool
+ IdentifierMap m_identifierMap;
+ JSValueMap m_jsValueMap;
+ NumberMap m_numberMap;
+ IdentifierStringMap m_stringMap;
+
+ JSGlobalData* m_globalData;
+
+ OpcodeID m_lastOpcodeID;
+
+ unsigned m_emitNodeDepth;
+
+ bool m_regeneratingForExceptionInfo;
+ CodeBlock* m_codeBlockBeingRegeneratedFrom;
+
+ static const unsigned s_maxEmitNodeDepth = 10000;
+ };
+
+}
+
+#endif // BytecodeGenerator_h
projects / apple / javascriptcore.git / blobdiff