Reviewed by Darin Adler.
        
        Changed the layout of the call frame from
        
        { header, parameters, locals | constants, temporaries }
        
        to
        
        { parameters, header | locals, constants, temporaries }
        
        This simplifies function entry+exit, and enables a number of future
        optimizations.
        
        13.5% speedup on empty call benchmark for bytecode; 23.6% speedup on
        empty call benchmark for CTI.
        
        SunSpider says no change. SunSpider --v8 says 1% faster.

        * VM/CTI.cpp:
        
        Added a bit of abstraction for calculating whether a register is a
        constant, since this patch changes that calculation:
        (JSC::CTI::isConstant):
        (JSC::CTI::getConstant):
        (JSC::CTI::emitGetArg):
        (JSC::CTI::emitGetPutArg):
        (JSC::CTI::getConstantImmediateNumericArg):

        Updated for changes to callframe header location:
        (JSC::CTI::emitPutToCallFrameHeader):
        (JSC::CTI::emitGetFromCallFrameHeader):
        (JSC::CTI::printOpcodeOperandTypes):
        
        Renamed to spite Oliver:
        (JSC::CTI::emitInitRegister):
        
        Added an abstraction for emitting a call through a register, so that
        calls through registers generate exception info, too:
        (JSC::CTI::emitCall):

        Updated to match the new callframe header layout, and to support calls
        through registers, which have no destination address:
        (JSC::CTI::compileOpCall):
        (JSC::CTI::privateCompileMainPass):
        (JSC::CTI::privateCompileSlowCases):
        (JSC::CTI::privateCompile):

        * VM/CTI.h:

        More of the above:
        (JSC::CallRecord::CallRecord):

        * VM/CodeBlock.cpp:

        Updated for new register layout:
        (JSC::registerName):
        (JSC::CodeBlock::dump):

        * VM/CodeBlock.h:
        
        Updated CodeBlock to track slightly different information about the
        register frame, and tweaked the style of an ASSERT_NOT_REACHED.
        (JSC::CodeBlock::CodeBlock):
        (JSC::CodeBlock::getStubInfo):

        * VM/CodeGenerator.cpp:
        
        Added some abstraction around constant register allocation, since this
        patch changes it, changed codegen to account for the new callframe
        layout, and added abstraction around register fetching code
        that used to assume that all local registers lived at negative indices,
        since vars now live at positive indices:
        (JSC::CodeGenerator::generate):
        (JSC::CodeGenerator::addVar):
        (JSC::CodeGenerator::addGlobalVar):
        (JSC::CodeGenerator::allocateConstants):
        (JSC::CodeGenerator::CodeGenerator):
        (JSC::CodeGenerator::addParameter):
        (JSC::CodeGenerator::registerFor):
        (JSC::CodeGenerator::constRegisterFor):
        (JSC::CodeGenerator::newRegister):
        (JSC::CodeGenerator::newTemporary):
        (JSC::CodeGenerator::highestUsedRegister):
        (JSC::CodeGenerator::addConstant):
        
        ASSERT that our caller referenced the registers it passed to us.
        Otherwise, we might overwrite them with parameters:
        (JSC::CodeGenerator::emitCall):
        (JSC::CodeGenerator::emitConstruct):

        * VM/CodeGenerator.h:
        
        Added some abstraction for getting a RegisterID for a given index,
        since the rules are a little weird:
        (JSC::CodeGenerator::registerFor):

        * VM/Machine.cpp:

        Utility function to transform a machine return PC to a virtual machine
        return VPC, for the sake of stack unwinding, since both PCs are stored
        in the same location now:
        (JSC::vPCForPC):

        Tweaked to account for new call frame:
        (JSC::Machine::initializeCallFrame):
        
        Tweaked to account for registerOffset supplied by caller:
        (JSC::slideRegisterWindowForCall):

        Tweaked to account for new register layout:
        (JSC::scopeChainForCall):
        (JSC::Machine::callEval):
        (JSC::Machine::dumpRegisters):
        (JSC::Machine::unwindCallFrame):
        (JSC::Machine::execute):

        Changed op_call and op_construct to implement the new calling convention:
        (JSC::Machine::privateExecute):

        Tweaked to account for the new register layout:
        (JSC::Machine::retrieveArguments):
        (JSC::Machine::retrieveCaller):
        (JSC::Machine::retrieveLastCaller):
        (JSC::Machine::callFrame):
        (JSC::Machine::getArgumentsData):

        Changed CTI call helpers to implement the new calling convention:
        (JSC::Machine::cti_op_call_JSFunction):
        (JSC::Machine::cti_op_call_NotJSFunction):
        (JSC::Machine::cti_op_ret_activation):
        (JSC::Machine::cti_op_ret_profiler):
        (JSC::Machine::cti_op_construct_JSConstruct):
        (JSC::Machine::cti_op_construct_NotJSConstruct):
        (JSC::Machine::cti_op_call_eval):

        * VM/Machine.h:

        * VM/Opcode.h:
        
        Renamed op_initialise_locals to op_init, because this opcode
        doesn't initialize all locals, and it doesn't initialize only locals.
        Also, to spite Oliver.
        
        * VM/RegisterFile.h:
        
        New call frame enumeration values:
        (JSC::RegisterFile::):

        Simplified the calculation of whether a RegisterID is a temporary,
        since we can no longer assume that all positive non-constant registers
        are temporaries:
        * VM/RegisterID.h:
        (JSC::RegisterID::RegisterID):
        (JSC::RegisterID::setTemporary):
        (JSC::RegisterID::isTemporary):

        Renamed firstArgumentIndex to firstParameterIndex because the assumption
        that this variable pertained to the actual arguments supplied by the
        caller caused me to write some buggy code:
        * kjs/Arguments.cpp:
        (JSC::ArgumentsData::ArgumentsData):
        (JSC::Arguments::Arguments):
        (JSC::Arguments::fillArgList):
        (JSC::Arguments::getOwnPropertySlot):
        (JSC::Arguments::put):

        Updated for new call frame layout:
        * kjs/DebuggerCallFrame.cpp:
        (JSC::DebuggerCallFrame::functionName):
        (JSC::DebuggerCallFrame::type):
        * kjs/DebuggerCallFrame.h:

        Changed the activation object to account for the fact that a call frame
        header now sits between parameters and local variables. This change
        requires all variable objects to do their own marking, since they
        now use their register storage differently:
        * kjs/JSActivation.cpp:
        (JSC::JSActivation::mark):
        (JSC::JSActivation::copyRegisters):
        (JSC::JSActivation::createArgumentsObject):
        * kjs/JSActivation.h:

        Updated global object to use the new interfaces required by the change
        to JSActivation above:
        * kjs/JSGlobalObject.cpp:
        (JSC::JSGlobalObject::reset):
        (JSC::JSGlobalObject::mark):
        (JSC::JSGlobalObject::copyGlobalsFrom):
        (JSC::JSGlobalObject::copyGlobalsTo):
        * kjs/JSGlobalObject.h:
        (JSC::JSGlobalObject::addStaticGlobals):

        Updated static scope object to use the new interfaces required by the 
        change to JSActivation above:
        * kjs/JSStaticScopeObject.cpp:
        (JSC::JSStaticScopeObject::mark):
        (JSC::JSStaticScopeObject::~JSStaticScopeObject):
        * kjs/JSStaticScopeObject.h:
        (JSC::JSStaticScopeObject::JSStaticScopeObject):
        (JSC::JSStaticScopeObject::d):

        Updated variable object to use the new interfaces required by the 
        change to JSActivation above:
        * kjs/JSVariableObject.cpp:
        (JSC::JSVariableObject::copyRegisterArray):
        (JSC::JSVariableObject::setRegisters):
        * kjs/JSVariableObject.h:

        Changed the bit twiddling in symbol table not to assume that all indices
        are negative, since they can be positive now:
        * kjs/SymbolTable.h:
        (JSC::SymbolTableEntry::SymbolTableEntry):
        (JSC::SymbolTableEntry::isNull):
        (JSC::SymbolTableEntry::getIndex):
        (JSC::SymbolTableEntry::getAttributes):
        (JSC::SymbolTableEntry::setAttributes):
        (JSC::SymbolTableEntry::isReadOnly):
        (JSC::SymbolTableEntry::pack):
        (JSC::SymbolTableEntry::isValidIndex):

        Changed call and construct nodes to ref their functions and/or bases,
        so that emitCall/emitConstruct doesn't overwrite them with parameters.
        Also, updated for rename to registerFor:
        * kjs/nodes.cpp:
        (JSC::ResolveNode::emitCode):
        (JSC::NewExprNode::emitCode):
        (JSC::EvalFunctionCallNode::emitCode):
        (JSC::FunctionCallValueNode::emitCode):
        (JSC::FunctionCallResolveNode::emitCode):
        (JSC::FunctionCallBracketNode::emitCode):
        (JSC::FunctionCallDotNode::emitCode):
        (JSC::PostfixResolveNode::emitCode):
        (JSC::DeleteResolveNode::emitCode):
        (JSC::TypeOfResolveNode::emitCode):
        (JSC::PrefixResolveNode::emitCode):
        (JSC::ReadModifyResolveNode::emitCode):
        (JSC::AssignResolveNode::emitCode):
        (JSC::ConstDeclNode::emitCodeSingle):
        (JSC::ForInNode::emitCode):

        Added abstraction for getting exception info out of a call through a
        register:
        * masm/X86Assembler.h:
        (JSC::X86Assembler::emitCall):
        
        Removed duplicate #if:
        * wtf/Platform.h:



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@36821 268f45cc-cd09-0410-ab3c-d52691b4dbfc