618 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			618 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===-- X86/X86CodeEmitter.cpp - Convert X86 code to machine code ---------===//
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| // 
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file was developed by the LLVM research group and is distributed under
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| // the University of Illinois Open Source License. See LICENSE.TXT for details.
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| // 
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| //===----------------------------------------------------------------------===//
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| //
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| // This file contains the pass that transforms the X86 machine instructions into
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| // actual executable machine code.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #define DEBUG_TYPE "jit"
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| #include "X86TargetMachine.h"
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| #include "X86.h"
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| #include "llvm/PassManager.h"
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| #include "llvm/CodeGen/MachineCodeEmitter.h"
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| #include "llvm/CodeGen/MachineFunctionPass.h"
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| #include "llvm/CodeGen/MachineInstr.h"
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| #include "llvm/CodeGen/Passes.h"
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| #include "llvm/Function.h"
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| #include "llvm/Support/Debug.h"
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| #include "llvm/ADT/Statistic.h"
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| #include "llvm/Config/alloca.h"
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| using namespace llvm;
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| 
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| namespace {
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|   Statistic<>
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|   NumEmitted("x86-emitter", "Number of machine instructions emitted");
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| 
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|   class JITResolver {
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|     MachineCodeEmitter &MCE;
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| 
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|     // LazyCodeGenMap - Keep track of call sites for functions that are to be
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|     // lazily resolved.
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|     std::map<unsigned, Function*> LazyCodeGenMap;
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| 
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|     // LazyResolverMap - Keep track of the lazy resolver created for a
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|     // particular function so that we can reuse them if necessary.
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|     std::map<Function*, unsigned> LazyResolverMap;
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|   public:
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|     JITResolver(MachineCodeEmitter &mce) : MCE(mce) {}
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|     unsigned getLazyResolver(Function *F);
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|     unsigned addFunctionReference(unsigned Address, Function *F);
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|     
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|   private:
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|     unsigned emitStubForFunction(Function *F);
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|     static void CompilationCallback();
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|     unsigned resolveFunctionReference(unsigned RetAddr);
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|   };
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| 
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|   static JITResolver &getResolver(MachineCodeEmitter &MCE) {
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|     static JITResolver *TheJITResolver = 0;
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|     if (TheJITResolver == 0)
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|       TheJITResolver = new JITResolver(MCE);
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|     return *TheJITResolver;
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|   }
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| }
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| 
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| 
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| void *X86JITInfo::getJITStubForFunction(Function *F, MachineCodeEmitter &MCE) {
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|   return (void*)((unsigned long)getResolver(MCE).getLazyResolver(F));
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| }
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| 
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| void X86JITInfo::replaceMachineCodeForFunction (void *Old, void *New) {
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|   char *OldByte = (char *) Old;
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|   *OldByte++ = 0xE9;                // Emit JMP opcode.
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|   int32_t *OldWord = (int32_t *) OldByte;
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|   int32_t NewAddr = (intptr_t) New;
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|   int32_t OldAddr = (intptr_t) OldWord;
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|   *OldWord = NewAddr - OldAddr - 4; // Emit PC-relative addr of New code.
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| }
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| 
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| /// addFunctionReference - This method is called when we need to emit the
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| /// address of a function that has not yet been emitted, so we don't know the
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| /// address.  Instead, we emit a call to the CompilationCallback method, and
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| /// keep track of where we are.
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| ///
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| unsigned JITResolver::addFunctionReference(unsigned Address, Function *F) {
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|   LazyCodeGenMap[Address] = F;  
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|   return (intptr_t)&JITResolver::CompilationCallback;
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| }
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| 
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| unsigned JITResolver::resolveFunctionReference(unsigned RetAddr) {
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|   std::map<unsigned, Function*>::iterator I = LazyCodeGenMap.find(RetAddr);
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|   assert(I != LazyCodeGenMap.end() && "Not in map!");
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|   Function *F = I->second;
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|   LazyCodeGenMap.erase(I);
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|   return MCE.forceCompilationOf(F);
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| }
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| 
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| unsigned JITResolver::getLazyResolver(Function *F) {
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|   std::map<Function*, unsigned>::iterator I = LazyResolverMap.lower_bound(F);
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|   if (I != LazyResolverMap.end() && I->first == F) return I->second;
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|   
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| //std::cerr << "Getting lazy resolver for : " << ((Value*)F)->getName() << "\n";
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| 
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|   unsigned Stub = emitStubForFunction(F);
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|   LazyResolverMap.insert(I, std::make_pair(F, Stub));
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|   return Stub;
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| }
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| 
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| void JITResolver::CompilationCallback() {
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|   unsigned *StackPtr = (unsigned*)__builtin_frame_address(0);
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|   unsigned RetAddr = (unsigned)(intptr_t)__builtin_return_address(0);
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|   assert(StackPtr[1] == RetAddr &&
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|          "Could not find return address on the stack!");
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| 
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|   // It's a stub if there is an interrupt marker after the call...
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|   bool isStub = ((unsigned char*)(intptr_t)RetAddr)[0] == 0xCD;
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| 
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|   // FIXME FIXME FIXME FIXME: __builtin_frame_address doesn't work if frame
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|   // pointer elimination has been performed.  Having a variable sized alloca
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|   // disables frame pointer elimination currently, even if it's dead.  This is a
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|   // gross hack.
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|   alloca(10+isStub);
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|   // FIXME FIXME FIXME FIXME
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| 
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|   // The call instruction should have pushed the return value onto the stack...
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|   RetAddr -= 4;  // Backtrack to the reference itself...
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| 
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| #if 0
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|   DEBUG(std::cerr << "In callback! Addr=0x" << std::hex << RetAddr
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|                   << " ESP=0x" << (unsigned)StackPtr << std::dec
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|                   << ": Resolving call to function: "
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|                   << TheVM->getFunctionReferencedName((void*)RetAddr) << "\n");
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| #endif
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| 
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|   // Sanity check to make sure this really is a call instruction...
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|   assert(((unsigned char*)(intptr_t)RetAddr)[-1] == 0xE8 &&"Not a call instr!");
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|   
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|   JITResolver &JR = getResolver(*(MachineCodeEmitter*)0);
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|   unsigned NewVal = JR.resolveFunctionReference(RetAddr);
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| 
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|   // Rewrite the call target... so that we don't fault every time we execute
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|   // the call.
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|   *(unsigned*)(intptr_t)RetAddr = NewVal-RetAddr-4;    
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| 
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|   if (isStub) {
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|     // If this is a stub, rewrite the call into an unconditional branch
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|     // instruction so that two return addresses are not pushed onto the stack
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|     // when the requested function finally gets called.  This also makes the
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|     // 0xCD byte (interrupt) dead, so the marker doesn't effect anything.
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|     ((unsigned char*)(intptr_t)RetAddr)[-1] = 0xE9;
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|   }
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| 
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|   // Change the return address to reexecute the call instruction...
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|   StackPtr[1] -= 5;
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| }
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| 
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| /// emitStubForFunction - This method is used by the JIT when it needs to emit
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| /// the address of a function for a function whose code has not yet been
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| /// generated.  In order to do this, it generates a stub which jumps to the lazy
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| /// function compiler, which will eventually get fixed to call the function
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| /// directly.
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| ///
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| unsigned JITResolver::emitStubForFunction(Function *F) {
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|   MCE.startFunctionStub(*F, 6);
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|   MCE.emitByte(0xE8);   // Call with 32 bit pc-rel destination...
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| 
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|   unsigned Address = addFunctionReference(MCE.getCurrentPCValue(), F);
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|   MCE.emitWord(Address-MCE.getCurrentPCValue()-4);
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| 
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|   MCE.emitByte(0xCD);   // Interrupt - Just a marker identifying the stub!
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|   return (intptr_t)MCE.finishFunctionStub(*F);
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| }
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| 
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| 
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| namespace {
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|   class Emitter : public MachineFunctionPass {
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|     const X86InstrInfo  *II;
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|     MachineCodeEmitter  &MCE;
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|     std::map<const MachineBasicBlock*, unsigned> BasicBlockAddrs;
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|     std::vector<std::pair<const MachineBasicBlock *, unsigned> > BBRefs;
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|   public:
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|     explicit Emitter(MachineCodeEmitter &mce) : II(0), MCE(mce) {}
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|     Emitter(MachineCodeEmitter &mce, const X86InstrInfo& ii)
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|         : II(&ii), MCE(mce) {}
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| 
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|     bool runOnMachineFunction(MachineFunction &MF);
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| 
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|     virtual const char *getPassName() const {
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|       return "X86 Machine Code Emitter";
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|     }
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| 
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|     void emitInstruction(const MachineInstr &MI);
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| 
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|   private:
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|     void emitBasicBlock(const MachineBasicBlock &MBB);
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| 
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|     void emitPCRelativeBlockAddress(const MachineBasicBlock *BB);
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|     void emitMaybePCRelativeValue(unsigned Address, bool isPCRelative);
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|     void emitGlobalAddressForCall(GlobalValue *GV);
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|     void emitGlobalAddressForPtr(GlobalValue *GV);
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| 
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|     void emitRegModRMByte(unsigned ModRMReg, unsigned RegOpcodeField);
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|     void emitSIBByte(unsigned SS, unsigned Index, unsigned Base);
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|     void emitConstant(unsigned Val, unsigned Size);
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| 
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|     void emitMemModRMByte(const MachineInstr &MI,
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|                           unsigned Op, unsigned RegOpcodeField);
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| 
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|   };
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| }
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| 
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| // This function is required by X86AsmPrinter.cpp to work around GAS bugs
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| void llvm::X86::emitInstruction(MachineCodeEmitter& mce,
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|                                 const X86InstrInfo& ii,
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|                                 const MachineInstr& mi)
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| {
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|     Emitter(mce, ii).emitInstruction(mi);
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| }
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| 
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| /// addPassesToEmitMachineCode - Add passes to the specified pass manager to get
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| /// machine code emitted.  This uses a MachineCodeEmitter object to handle
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| /// actually outputting the machine code and resolving things like the address
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| /// of functions.  This method should returns true if machine code emission is
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| /// not supported.
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| ///
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| bool X86TargetMachine::addPassesToEmitMachineCode(FunctionPassManager &PM,
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|                                                   MachineCodeEmitter &MCE) {
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|   PM.add(new Emitter(MCE));
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|   // Delete machine code for this function
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|   PM.add(createMachineCodeDeleter());
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|   return false;
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| }
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| 
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| bool Emitter::runOnMachineFunction(MachineFunction &MF) {
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|   II = ((X86TargetMachine&)MF.getTarget()).getInstrInfo();
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| 
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|   MCE.startFunction(MF);
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|   MCE.emitConstantPool(MF.getConstantPool());
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|   for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I)
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|     emitBasicBlock(*I);
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|   MCE.finishFunction(MF);
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| 
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|   // Resolve all forward branches now...
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|   for (unsigned i = 0, e = BBRefs.size(); i != e; ++i) {
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|     unsigned Location = BasicBlockAddrs[BBRefs[i].first];
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|     unsigned Ref = BBRefs[i].second;
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|     MCE.emitWordAt (Location-Ref-4, (unsigned*)(intptr_t)Ref);
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|   }
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|   BBRefs.clear();
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|   BasicBlockAddrs.clear();
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|   return false;
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| }
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| 
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| void Emitter::emitBasicBlock(const MachineBasicBlock &MBB) {
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|   if (uint64_t Addr = MCE.getCurrentPCValue())
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|     BasicBlockAddrs[&MBB] = Addr;
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| 
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|   for (MachineBasicBlock::const_iterator I = MBB.begin(), E = MBB.end(); I != E; ++I)
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|     emitInstruction(*I);
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| }
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| 
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| /// emitPCRelativeBlockAddress - This method emits the PC relative address of
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| /// the specified basic block, or if the basic block hasn't been emitted yet
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| /// (because this is a forward branch), it keeps track of the information
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| /// necessary to resolve this address later (and emits a dummy value).
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| ///
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| void Emitter::emitPCRelativeBlockAddress(const MachineBasicBlock *MBB) {
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|   // FIXME: Emit backward branches directly
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|   BBRefs.push_back(std::make_pair(MBB, MCE.getCurrentPCValue()));
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|   MCE.emitWord(0);
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| }
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| 
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| /// emitMaybePCRelativeValue - Emit a 32-bit address which may be PC relative.
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| ///
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| void Emitter::emitMaybePCRelativeValue(unsigned Address, bool isPCRelative) {
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|   if (isPCRelative)
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|     MCE.emitWord(Address-MCE.getCurrentPCValue()-4);
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|   else
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|     MCE.emitWord(Address);
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| }
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| 
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| /// emitGlobalAddressForCall - Emit the specified address to the code stream
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| /// assuming this is part of a function call, which is PC relative.
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| ///
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| void Emitter::emitGlobalAddressForCall(GlobalValue *GV) {
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|   // Get the address from the backend...
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|   unsigned Address = MCE.getGlobalValueAddress(GV);
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|   
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|   if (Address == 0) {
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|     // FIXME: this is JIT specific!
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|     Address = getResolver(MCE).addFunctionReference(MCE.getCurrentPCValue(),
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|                                                     cast<Function>(GV));
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|   }
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|   emitMaybePCRelativeValue(Address, true);
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| }
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| 
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| /// emitGlobalAddress - Emit the specified address to the code stream assuming
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| /// this is part of a "take the address of a global" instruction, which is not
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| /// PC relative.
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| ///
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| void Emitter::emitGlobalAddressForPtr(GlobalValue *GV) {
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|   // Get the address from the backend...
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|   unsigned Address = MCE.getGlobalValueAddress(GV);
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| 
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|   // If the machine code emitter doesn't know what the address IS yet, we have
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|   // to take special measures.
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|   //
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|   if (Address == 0) {
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|     // FIXME: this is JIT specific!
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|     Address = getResolver(MCE).getLazyResolver((Function*)GV);
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|   }
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| 
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|   emitMaybePCRelativeValue(Address, false);
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| }
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| 
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| 
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| 
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| /// N86 namespace - Native X86 Register numbers... used by X86 backend.
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| ///
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| namespace N86 {
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|   enum {
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|     EAX = 0, ECX = 1, EDX = 2, EBX = 3, ESP = 4, EBP = 5, ESI = 6, EDI = 7
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|   };
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| }
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| 
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| 
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| // getX86RegNum - This function maps LLVM register identifiers to their X86
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| // specific numbering, which is used in various places encoding instructions.
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| //
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| static unsigned getX86RegNum(unsigned RegNo) {
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|   switch(RegNo) {
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|   case X86::EAX: case X86::AX: case X86::AL: return N86::EAX;
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|   case X86::ECX: case X86::CX: case X86::CL: return N86::ECX;
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|   case X86::EDX: case X86::DX: case X86::DL: return N86::EDX;
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|   case X86::EBX: case X86::BX: case X86::BL: return N86::EBX;
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|   case X86::ESP: case X86::SP: case X86::AH: return N86::ESP;
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|   case X86::EBP: case X86::BP: case X86::CH: return N86::EBP;
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|   case X86::ESI: case X86::SI: case X86::DH: return N86::ESI;
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|   case X86::EDI: case X86::DI: case X86::BH: return N86::EDI;
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| 
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|   case X86::ST0: case X86::ST1: case X86::ST2: case X86::ST3:
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|   case X86::ST4: case X86::ST5: case X86::ST6: case X86::ST7:
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|     return RegNo-X86::ST0;
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|   default:
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|     assert(MRegisterInfo::isVirtualRegister(RegNo) &&
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|            "Unknown physical register!");
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|     assert(0 && "Register allocator hasn't allocated reg correctly yet!");
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|     return 0;
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|   }
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| }
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| 
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| inline static unsigned char ModRMByte(unsigned Mod, unsigned RegOpcode,
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|                                       unsigned RM) {
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|   assert(Mod < 4 && RegOpcode < 8 && RM < 8 && "ModRM Fields out of range!");
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|   return RM | (RegOpcode << 3) | (Mod << 6);
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| }
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| 
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| void Emitter::emitRegModRMByte(unsigned ModRMReg, unsigned RegOpcodeFld){
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|   MCE.emitByte(ModRMByte(3, RegOpcodeFld, getX86RegNum(ModRMReg)));
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| }
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| 
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| void Emitter::emitSIBByte(unsigned SS, unsigned Index, unsigned Base) {
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|   // SIB byte is in the same format as the ModRMByte...
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|   MCE.emitByte(ModRMByte(SS, Index, Base));
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| }
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| 
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| void Emitter::emitConstant(unsigned Val, unsigned Size) {
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|   // Output the constant in little endian byte order...
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|   for (unsigned i = 0; i != Size; ++i) {
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|     MCE.emitByte(Val & 255);
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|     Val >>= 8;
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|   }
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| }
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| 
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| static bool isDisp8(int Value) {
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|   return Value == (signed char)Value;
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| }
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| 
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| void Emitter::emitMemModRMByte(const MachineInstr &MI,
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|                                unsigned Op, unsigned RegOpcodeField) {
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|   const MachineOperand &Disp     = MI.getOperand(Op+3);
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|   if (MI.getOperand(Op).isConstantPoolIndex()) {
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|     // Emit a direct address reference [disp32] where the displacement of the
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|     // constant pool entry is controlled by the MCE.
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|     MCE.emitByte(ModRMByte(0, RegOpcodeField, 5));
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|     unsigned Index = MI.getOperand(Op).getConstantPoolIndex();
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|     unsigned Address = MCE.getConstantPoolEntryAddress(Index);
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|     MCE.emitWord(Address+Disp.getImmedValue());
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|     return;
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|   }
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| 
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|   const MachineOperand &BaseReg  = MI.getOperand(Op);
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|   const MachineOperand &Scale    = MI.getOperand(Op+1);
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|   const MachineOperand &IndexReg = MI.getOperand(Op+2);
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| 
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|   // Is a SIB byte needed?
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|   if (IndexReg.getReg() == 0 && BaseReg.getReg() != X86::ESP) {
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|     if (BaseReg.getReg() == 0) {  // Just a displacement?
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|       // Emit special case [disp32] encoding
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|       MCE.emitByte(ModRMByte(0, RegOpcodeField, 5));
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|       emitConstant(Disp.getImmedValue(), 4);
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|     } else {
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|       unsigned BaseRegNo = getX86RegNum(BaseReg.getReg());
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|       if (Disp.getImmedValue() == 0 && BaseRegNo != N86::EBP) {
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|         // Emit simple indirect register encoding... [EAX] f.e.
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|         MCE.emitByte(ModRMByte(0, RegOpcodeField, BaseRegNo));
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|       } else if (isDisp8(Disp.getImmedValue())) {
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|         // Emit the disp8 encoding... [REG+disp8]
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|         MCE.emitByte(ModRMByte(1, RegOpcodeField, BaseRegNo));
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|         emitConstant(Disp.getImmedValue(), 1);
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|       } else {
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|         // Emit the most general non-SIB encoding: [REG+disp32]
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|         MCE.emitByte(ModRMByte(2, RegOpcodeField, BaseRegNo));
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|         emitConstant(Disp.getImmedValue(), 4);
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|       }
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|     }
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| 
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|   } else {  // We need a SIB byte, so start by outputting the ModR/M byte first
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|     assert(IndexReg.getReg() != X86::ESP && "Cannot use ESP as index reg!");
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| 
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|     bool ForceDisp32 = false;
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|     bool ForceDisp8  = false;
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|     if (BaseReg.getReg() == 0) {
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|       // If there is no base register, we emit the special case SIB byte with
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|       // MOD=0, BASE=5, to JUST get the index, scale, and displacement.
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|       MCE.emitByte(ModRMByte(0, RegOpcodeField, 4));
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|       ForceDisp32 = true;
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|     } else if (Disp.getImmedValue() == 0 && BaseReg.getReg() != X86::EBP) {
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|       // Emit no displacement ModR/M byte
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|       MCE.emitByte(ModRMByte(0, RegOpcodeField, 4));
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|     } else if (isDisp8(Disp.getImmedValue())) {
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|       // Emit the disp8 encoding...
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|       MCE.emitByte(ModRMByte(1, RegOpcodeField, 4));
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|       ForceDisp8 = true;           // Make sure to force 8 bit disp if Base=EBP
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|     } else {
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|       // Emit the normal disp32 encoding...
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|       MCE.emitByte(ModRMByte(2, RegOpcodeField, 4));
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|     }
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| 
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|     // Calculate what the SS field value should be...
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|     static const unsigned SSTable[] = { ~0, 0, 1, ~0, 2, ~0, ~0, ~0, 3 };
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|     unsigned SS = SSTable[Scale.getImmedValue()];
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| 
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|     if (BaseReg.getReg() == 0) {
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|       // Handle the SIB byte for the case where there is no base.  The
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|       // displacement has already been output.
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|       assert(IndexReg.getReg() && "Index register must be specified!");
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|       emitSIBByte(SS, getX86RegNum(IndexReg.getReg()), 5);
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|     } else {
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|       unsigned BaseRegNo = getX86RegNum(BaseReg.getReg());
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|       unsigned IndexRegNo;
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|       if (IndexReg.getReg())
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| 	IndexRegNo = getX86RegNum(IndexReg.getReg());
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|       else
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| 	IndexRegNo = 4;   // For example [ESP+1*<noreg>+4]
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|       emitSIBByte(SS, IndexRegNo, BaseRegNo);
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|     }
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| 
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|     // Do we need to output a displacement?
 | |
|     if (Disp.getImmedValue() != 0 || ForceDisp32 || ForceDisp8) {
 | |
|       if (!ForceDisp32 && isDisp8(Disp.getImmedValue()))
 | |
|         emitConstant(Disp.getImmedValue(), 1);
 | |
|       else
 | |
|         emitConstant(Disp.getImmedValue(), 4);
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| static unsigned sizeOfImm(const TargetInstrDescriptor &Desc) {
 | |
|   switch (Desc.TSFlags & X86II::ImmMask) {
 | |
|   case X86II::Imm8:   return 1;
 | |
|   case X86II::Imm16:  return 2;
 | |
|   case X86II::Imm32:  return 4;
 | |
|   default: assert(0 && "Immediate size not set!");
 | |
|     return 0;
 | |
|   }
 | |
| }
 | |
| 
 | |
| void Emitter::emitInstruction(const MachineInstr &MI) {
 | |
|   NumEmitted++;  // Keep track of the # of mi's emitted
 | |
| 
 | |
|   unsigned Opcode = MI.getOpcode();
 | |
|   const TargetInstrDescriptor &Desc = II->get(Opcode);
 | |
| 
 | |
|   // Emit the repeat opcode prefix as needed.
 | |
|   if ((Desc.TSFlags & X86II::Op0Mask) == X86II::REP) MCE.emitByte(0xF3);
 | |
| 
 | |
|   // Emit instruction prefixes if necessary
 | |
|   if (Desc.TSFlags & X86II::OpSize) MCE.emitByte(0x66);// Operand size...
 | |
| 
 | |
|   switch (Desc.TSFlags & X86II::Op0Mask) {
 | |
|   case X86II::TB:
 | |
|     MCE.emitByte(0x0F);   // Two-byte opcode prefix
 | |
|     break;
 | |
|   case X86II::REP: break; // already handled.
 | |
|   case X86II::D8: case X86II::D9: case X86II::DA: case X86II::DB:
 | |
|   case X86II::DC: case X86II::DD: case X86II::DE: case X86II::DF:
 | |
|     MCE.emitByte(0xD8+
 | |
| 		 (((Desc.TSFlags & X86II::Op0Mask)-X86II::D8)
 | |
| 		                   >> X86II::Op0Shift));
 | |
|     break; // Two-byte opcode prefix
 | |
|   default: assert(0 && "Invalid prefix!");
 | |
|   case 0: break;  // No prefix!
 | |
|   }
 | |
| 
 | |
|   unsigned char BaseOpcode = II->getBaseOpcodeFor(Opcode);
 | |
|   switch (Desc.TSFlags & X86II::FormMask) {
 | |
|   default: assert(0 && "Unknown FormMask value in X86 MachineCodeEmitter!");
 | |
|   case X86II::Pseudo:
 | |
|     if (Opcode != X86::IMPLICIT_USE &&
 | |
|         Opcode != X86::IMPLICIT_DEF &&
 | |
|         Opcode != X86::FP_REG_KILL)
 | |
|       std::cerr << "X86 Machine Code Emitter: No 'form', not emitting: " << MI;
 | |
|     break;
 | |
| 
 | |
|   case X86II::RawFrm:
 | |
|     MCE.emitByte(BaseOpcode);
 | |
|     if (MI.getNumOperands() == 1) {
 | |
|       const MachineOperand &MO = MI.getOperand(0);
 | |
|       if (MO.isMachineBasicBlock()) {
 | |
|         emitPCRelativeBlockAddress(MO.getMachineBasicBlock());
 | |
|       } else if (MO.isGlobalAddress()) {
 | |
|         assert(MO.isPCRelative() && "Call target is not PC Relative?");
 | |
|         emitGlobalAddressForCall(MO.getGlobal());
 | |
|       } else if (MO.isExternalSymbol()) {
 | |
|         unsigned Address = MCE.getGlobalValueAddress(MO.getSymbolName());
 | |
|         assert(Address && "Unknown external symbol!");
 | |
|         emitMaybePCRelativeValue(Address, MO.isPCRelative());
 | |
|       } else if (MO.isImmediate()) {
 | |
|         emitConstant(MO.getImmedValue(), sizeOfImm(Desc));        
 | |
|       } else {
 | |
| 	assert(0 && "Unknown RawFrm operand!");
 | |
|       }
 | |
|     }
 | |
|     break;
 | |
| 
 | |
|   case X86II::AddRegFrm:
 | |
|     MCE.emitByte(BaseOpcode + getX86RegNum(MI.getOperand(0).getReg()));
 | |
|     if (MI.getNumOperands() == 2) {
 | |
|       const MachineOperand &MO1 = MI.getOperand(1);
 | |
|       if (Value *V = MO1.getVRegValueOrNull()) {
 | |
| 	assert(sizeOfImm(Desc) == 4 && "Don't know how to emit non-pointer values!");
 | |
|         emitGlobalAddressForPtr(cast<GlobalValue>(V));
 | |
|       } else if (MO1.isGlobalAddress()) {
 | |
| 	assert(sizeOfImm(Desc) == 4 && "Don't know how to emit non-pointer values!");
 | |
|         assert(!MO1.isPCRelative() && "Function pointer ref is PC relative?");
 | |
|         emitGlobalAddressForPtr(MO1.getGlobal());
 | |
|       } else if (MO1.isExternalSymbol()) {
 | |
| 	assert(sizeOfImm(Desc) == 4 && "Don't know how to emit non-pointer values!");
 | |
| 
 | |
|         unsigned Address = MCE.getGlobalValueAddress(MO1.getSymbolName());
 | |
|         assert(Address && "Unknown external symbol!");
 | |
|         emitMaybePCRelativeValue(Address, MO1.isPCRelative());
 | |
|       } else {
 | |
|         emitConstant(MO1.getImmedValue(), sizeOfImm(Desc));
 | |
|       }
 | |
|     }
 | |
|     break;
 | |
| 
 | |
|   case X86II::MRMDestReg: {
 | |
|     MCE.emitByte(BaseOpcode);
 | |
|     emitRegModRMByte(MI.getOperand(0).getReg(),
 | |
|                      getX86RegNum(MI.getOperand(1).getReg()));
 | |
|     if (MI.getNumOperands() == 3)
 | |
|       emitConstant(MI.getOperand(2).getImmedValue(), sizeOfImm(Desc));
 | |
|     break;
 | |
|   }
 | |
|   case X86II::MRMDestMem:
 | |
|     MCE.emitByte(BaseOpcode);
 | |
|     emitMemModRMByte(MI, 0, getX86RegNum(MI.getOperand(4).getReg()));
 | |
|     if (MI.getNumOperands() == 6)
 | |
|       emitConstant(MI.getOperand(5).getImmedValue(), sizeOfImm(Desc));
 | |
|     break;
 | |
| 
 | |
|   case X86II::MRMSrcReg:
 | |
|     MCE.emitByte(BaseOpcode);
 | |
| 
 | |
|     emitRegModRMByte(MI.getOperand(1).getReg(),
 | |
|                      getX86RegNum(MI.getOperand(0).getReg()));
 | |
|     if (MI.getNumOperands() == 3)
 | |
|       emitConstant(MI.getOperand(2).getImmedValue(), sizeOfImm(Desc));
 | |
|     break;
 | |
| 
 | |
|   case X86II::MRMSrcMem:
 | |
|     MCE.emitByte(BaseOpcode);
 | |
|     emitMemModRMByte(MI, 1, getX86RegNum(MI.getOperand(0).getReg()));
 | |
|     if (MI.getNumOperands() == 2+4)
 | |
|       emitConstant(MI.getOperand(5).getImmedValue(), sizeOfImm(Desc));
 | |
|     break;
 | |
| 
 | |
|   case X86II::MRM0r: case X86II::MRM1r:
 | |
|   case X86II::MRM2r: case X86II::MRM3r:
 | |
|   case X86II::MRM4r: case X86II::MRM5r:
 | |
|   case X86II::MRM6r: case X86II::MRM7r:
 | |
|     MCE.emitByte(BaseOpcode);
 | |
|     emitRegModRMByte(MI.getOperand(0).getReg(),
 | |
|                      (Desc.TSFlags & X86II::FormMask)-X86II::MRM0r);
 | |
| 
 | |
|     if (MI.getOperand(MI.getNumOperands()-1).isImmediate()) {
 | |
|       emitConstant(MI.getOperand(MI.getNumOperands()-1).getImmedValue(), sizeOfImm(Desc));
 | |
|     }
 | |
|     break;
 | |
| 
 | |
|   case X86II::MRM0m: case X86II::MRM1m:
 | |
|   case X86II::MRM2m: case X86II::MRM3m:
 | |
|   case X86II::MRM4m: case X86II::MRM5m:
 | |
|   case X86II::MRM6m: case X86II::MRM7m: 
 | |
|     MCE.emitByte(BaseOpcode);
 | |
|     emitMemModRMByte(MI, 0, (Desc.TSFlags & X86II::FormMask)-X86II::MRM0m);
 | |
| 
 | |
|     if (MI.getNumOperands() == 5) {
 | |
|       if (MI.getOperand(4).isImmediate())
 | |
|         emitConstant(MI.getOperand(4).getImmedValue(), sizeOfImm(Desc));
 | |
|       else if (MI.getOperand(4).isGlobalAddress())
 | |
|         emitGlobalAddressForPtr(MI.getOperand(4).getGlobal());
 | |
|       else
 | |
|         assert(0 && "Unknown operand!");
 | |
|     }
 | |
|     break;
 | |
|   }
 | |
| }
 |