lib/CodeGen/MachineFunction.cpp - fp2-dev/platform/external/llvm - Gitiles

 //===-- MachineFunction.cpp -----------------------------------------------===//
 //
 // Collect native machine code information for a function.  This allows
 // target-specific information about the generated code to be stored with each
 // function.
 //
 //===----------------------------------------------------------------------===//

 #include "llvm/CodeGen/MachineInstr.h"  // For debug output
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineCodeForInstruction.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/MachineFrameInfo.h"
 #include "llvm/Target/MachineCacheInfo.h"
 #include "llvm/Function.h"
 #include "llvm/iOther.h"
 #include "llvm/Pass.h"
 #include <limits.h>

 const int INVALID_FRAME_OFFSET = INT_MAX; // std::numeric_limits<int>::max();

 static AnnotationID MCFM_AID(
                  AnnotationManager::getID("CodeGen::MachineCodeForFunction"));


 //===---------------------------------------------------------------------===//
 // Code generation/destruction passes
 //===---------------------------------------------------------------------===//

 namespace {
   class ConstructMachineFunction : public FunctionPass {
     TargetMachine &Target;
   public:
     ConstructMachineFunction(TargetMachine &T) : Target(T) {}

     const char *getPassName() const {
       return "ConstructMachineFunction";
     }

     bool runOnFunction(Function &F) {
       MachineFunction::construct(&F, Target);
       return false;
     }
   };

   struct DestroyMachineFunction : public FunctionPass {
     const char *getPassName() const { return "FreeMachineFunction"; }

     static void freeMachineCode(Instruction &I) {
       MachineCodeForInstruction::destroy(&I);
     }

     bool runOnFunction(Function &F) {
       for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE; ++FI)
         for (BasicBlock::iterator I = FI->begin(), E = FI->end(); I != E; ++I)
           MachineCodeForInstruction::get(I).dropAllReferences();

       for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE; ++FI)
         for_each(FI->begin(), FI->end(), freeMachineCode);

       return false;
     }
   };
 }

 Pass *createMachineCodeConstructionPass(TargetMachine &Target) {
   return new ConstructMachineFunction(Target);
 }

 Pass *createMachineCodeDestructionPass() {
   return new DestroyMachineFunction();
 }


 //===---------------------------------------------------------------------===//
 // MachineFunction implementation
 //===---------------------------------------------------------------------===//

 // The next two methods are used to construct and to retrieve
 // the MachineCodeForFunction object for the given function.
 // construct() -- Allocates and initializes for a given function and target
 // get()       -- Returns a handle to the object.
 //                This should not be called before "construct()"
 //                for a given Function.
 //
 MachineFunction&
 MachineFunction::construct(const Function *Fn, const TargetMachine &Tar)
 {
   assert(Fn->getAnnotation(MCFM_AID) == 0 &&
          "Object already exists for this function!");
   MachineFunction* mcInfo = new MachineFunction(Fn, Tar);
   Fn->addAnnotation(mcInfo);
   return *mcInfo;
 }

 void
 MachineFunction::destruct(const Function *Fn)
 {
   bool Deleted = Fn->deleteAnnotation(MCFM_AID);
   assert(Deleted && "Machine code did not exist for function!");
 }

 MachineFunction& MachineFunction::get(const Function *F)
 {
   MachineFunction *mc = (MachineFunction*)F->getAnnotation(MCFM_AID);
   assert(mc && "Call construct() method first to allocate the object");
   return *mc;
 }

 static unsigned
 ComputeMaxOptionalArgsSize(const TargetMachine& target, const Function *F,
                            unsigned &maxOptionalNumArgs)
 {
   const MachineFrameInfo& frameInfo = target.getFrameInfo();

   unsigned maxSize = 0;

   for (Function::const_iterator BB = F->begin(), BBE = F->end(); BB !=BBE; ++BB)
     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I)
       if (const CallInst *callInst = dyn_cast<CallInst>(&*I))
         {
           unsigned numOperands = callInst->getNumOperands() - 1;
           int numExtra = (int)numOperands-frameInfo.getNumFixedOutgoingArgs();
           if (numExtra <= 0)
             continue;

           unsigned int sizeForThisCall;
           if (frameInfo.argsOnStackHaveFixedSize())
             {
               int argSize = frameInfo.getSizeOfEachArgOnStack();
               sizeForThisCall = numExtra * (unsigned) argSize;
             }
           else
             {
               assert(0 && "UNTESTED CODE: Size per stack argument is not "
                      "fixed on this architecture: use actual arg sizes to "
                      "compute MaxOptionalArgsSize");
               sizeForThisCall = 0;
               for (unsigned i = 0; i < numOperands; ++i)
                 sizeForThisCall += target.DataLayout.getTypeSize(callInst->
                                               getOperand(i)->getType());
             }

           if (maxSize < sizeForThisCall)
             maxSize = sizeForThisCall;

           if ((int)maxOptionalNumArgs < numExtra)
             maxOptionalNumArgs = (unsigned) numExtra;
         }

   return maxSize;
 }

 // Align data larger than one L1 cache line on L1 cache line boundaries.
 // Align all smaller data on the next higher 2^x boundary (4, 8, ...),
 // but not higher than the alignment of the largest type we support
 // (currently a double word). -- see class TargetData).
 //
 // This function is similar to the corresponding function in EmitAssembly.cpp
 // but they are unrelated.  This one does not align at more than a
 // double-word boundary whereas that one might.
 //
 inline unsigned int
 SizeToAlignment(unsigned int size, const TargetMachine& target)
 {
   unsigned short cacheLineSize = target.getCacheInfo().getCacheLineSize(1);
   if (size > (unsigned) cacheLineSize / 2)
     return cacheLineSize;
   else
     for (unsigned sz=1; /*no condition*/; sz *= 2)
       if (sz >= size || sz >= target.DataLayout.getDoubleAlignment())
         return sz;
 }


 /*ctor*/
 MachineFunction::MachineFunction(const Function *F,
                                  const TargetMachine& target)
   : Annotation(MCFM_AID),
     Fn(F), Target(target), staticStackSize(0),
     automaticVarsSize(0), regSpillsSize(0),
     maxOptionalArgsSize(0), maxOptionalNumArgs(0),
     currentTmpValuesSize(0), maxTmpValuesSize(0), compiledAsLeaf(false),
     spillsAreaFrozen(false), automaticVarsAreaFrozen(false)
 {
   maxOptionalArgsSize = ComputeMaxOptionalArgsSize(target, Fn,
                                                    maxOptionalNumArgs);
   staticStackSize = maxOptionalArgsSize
                     + target.getFrameInfo().getMinStackFrameSize();
 }

 int
 MachineFunction::computeOffsetforLocalVar(const TargetMachine& target,
                                                const Value* val,
                                                unsigned int& getPaddedSize,
                                                unsigned int  sizeToUse)
 {
   if (sizeToUse == 0)
     sizeToUse = target.findOptimalStorageSize(val->getType());
   unsigned int align = SizeToAlignment(sizeToUse, target);

   bool growUp;
   int firstOffset = target.getFrameInfo().getFirstAutomaticVarOffset(*this,
                                                                      growUp);
   int offset = growUp? firstOffset + getAutomaticVarsSize()
                      : firstOffset - (getAutomaticVarsSize() + sizeToUse);

   int aligned = target.getFrameInfo().adjustAlignment(offset, growUp, align);
   getPaddedSize = sizeToUse + abs(aligned - offset);

   return aligned;
 }

 int
 MachineFunction::allocateLocalVar(const TargetMachine& target,
                                        const Value* val,
                                        unsigned int sizeToUse)
 {
   assert(! automaticVarsAreaFrozen &&
          "Size of auto vars area has been used to compute an offset so "
          "no more automatic vars should be allocated!");

   // Check if we've allocated a stack slot for this value already
   //
   int offset = getOffset(val);
   if (offset == INVALID_FRAME_OFFSET)
     {
       unsigned int getPaddedSize;
       offset = computeOffsetforLocalVar(target, val, getPaddedSize, sizeToUse);
       offsets[val] = offset;
       incrementAutomaticVarsSize(getPaddedSize);
     }
   return offset;
 }

 int
 MachineFunction::allocateSpilledValue(const TargetMachine& target,
                                            const Type* type)
 {
   assert(! spillsAreaFrozen &&
          "Size of reg spills area has been used to compute an offset so "
          "no more register spill slots should be allocated!");

   unsigned int size  = target.DataLayout.getTypeSize(type);
   unsigned char align = target.DataLayout.getTypeAlignment(type);

   bool growUp;
   int firstOffset = target.getFrameInfo().getRegSpillAreaOffset(*this, growUp);

   int offset = growUp? firstOffset + getRegSpillsSize()
                      : firstOffset - (getRegSpillsSize() + size);

   int aligned = target.getFrameInfo().adjustAlignment(offset, growUp, align);
   size += abs(aligned - offset); // include alignment padding in size

   incrementRegSpillsSize(size);  // update size of reg. spills area

   return aligned;
 }

 int
 MachineFunction::pushTempValue(const TargetMachine& target,
                                     unsigned int size)
 {
   unsigned int align = SizeToAlignment(size, target);

   bool growUp;
   int firstOffset = target.getFrameInfo().getTmpAreaOffset(*this, growUp);

   int offset = growUp? firstOffset + currentTmpValuesSize
                      : firstOffset - (currentTmpValuesSize + size);

   int aligned = target.getFrameInfo().adjustAlignment(offset, growUp, align);
   size += abs(aligned - offset); // include alignment padding in size

   incrementTmpAreaSize(size);    // update "current" size of tmp area

   return aligned;
 }

 void
 MachineFunction::popAllTempValues(const TargetMachine& target)
 {
   resetTmpAreaSize();            // clear tmp area to reuse
 }

 int
 MachineFunction::getOffset(const Value* val) const
 {
   hash_map<const Value*, int>::const_iterator pair = offsets.find(val);
   return (pair == offsets.end()) ? INVALID_FRAME_OFFSET : pair->second;
 }

 void
 MachineFunction::dump() const
 {
   std::cerr << "\n" << Fn->getReturnType()
             << " \"" << Fn->getName() << "\"\n";

   for (const_iterator BB = begin(); BB != end(); ++BB) {
     std::cerr << "\n" << BB->getBasicBlock()->getName() << " ("
               << (const void*)BB->getBasicBlock() << ")" << ":" << "\n";
     for (MachineBasicBlock::const_iterator I = BB->begin(); I != BB->end(); ++I)
       std::cerr << "\t" << *I;
   }
   std::cerr << "\nEnd function \"" << Fn->getName() << "\"\n\n";
 }
	//===-- MachineFunction.cpp -----------------------------------------------===//
	//
	// Collect native machine code information for a function. This allows
	// target-specific information about the generated code to be stored with each
	// function.
	//
	//===----------------------------------------------------------------------===//

	#include "llvm/CodeGen/MachineInstr.h" // For debug output
	#include "llvm/CodeGen/MachineFunction.h"
	#include "llvm/CodeGen/MachineCodeForInstruction.h"
	#include "llvm/Target/TargetMachine.h"
	#include "llvm/Target/MachineFrameInfo.h"
	#include "llvm/Target/MachineCacheInfo.h"
	#include "llvm/Function.h"
	#include "llvm/iOther.h"
	#include "llvm/Pass.h"
	#include <limits.h>

	const int INVALID_FRAME_OFFSET = INT_MAX; // std::numeric_limits<int>::max();

	static AnnotationID MCFM_AID(
	AnnotationManager::getID("CodeGen::MachineCodeForFunction"));


	//===---------------------------------------------------------------------===//
	// Code generation/destruction passes
	//===---------------------------------------------------------------------===//

	namespace {
	class ConstructMachineFunction : public FunctionPass {
	TargetMachine &Target;
	public:
	ConstructMachineFunction(TargetMachine &T) : Target(T) {}

	const char *getPassName() const {
	return "ConstructMachineFunction";
	}

	bool runOnFunction(Function &F) {
	MachineFunction::construct(&F, Target);
	return false;
	}
	};

	struct DestroyMachineFunction : public FunctionPass {
	const char *getPassName() const { return "FreeMachineFunction"; }

	static void freeMachineCode(Instruction &I) {
	MachineCodeForInstruction::destroy(&I);
	}

	bool runOnFunction(Function &F) {
	for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE; ++FI)
	for (BasicBlock::iterator I = FI->begin(), E = FI->end(); I != E; ++I)
	MachineCodeForInstruction::get(I).dropAllReferences();

	for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE; ++FI)
	for_each(FI->begin(), FI->end(), freeMachineCode);

	return false;
	}
	};
	}

	Pass *createMachineCodeConstructionPass(TargetMachine &Target) {
	return new ConstructMachineFunction(Target);
	}

	Pass *createMachineCodeDestructionPass() {
	return new DestroyMachineFunction();
	}


	//===---------------------------------------------------------------------===//
	// MachineFunction implementation
	//===---------------------------------------------------------------------===//

	// The next two methods are used to construct and to retrieve
	// the MachineCodeForFunction object for the given function.
	// construct() -- Allocates and initializes for a given function and target
	// get() -- Returns a handle to the object.
	// This should not be called before "construct()"
	// for a given Function.
	//
	MachineFunction&
	MachineFunction::construct(const Function *Fn, const TargetMachine &Tar)
	{
	assert(Fn->getAnnotation(MCFM_AID) == 0 &&
	"Object already exists for this function!");
	MachineFunction* mcInfo = new MachineFunction(Fn, Tar);
	Fn->addAnnotation(mcInfo);
	return *mcInfo;
	}

	void
	MachineFunction::destruct(const Function *Fn)
	{
	bool Deleted = Fn->deleteAnnotation(MCFM_AID);
	assert(Deleted && "Machine code did not exist for function!");
	}

	MachineFunction& MachineFunction::get(const Function *F)
	{
	MachineFunction mc = (MachineFunction)F->getAnnotation(MCFM_AID);
	assert(mc && "Call construct() method first to allocate the object");
	return *mc;
	}

	static unsigned
	ComputeMaxOptionalArgsSize(const TargetMachine& target, const Function *F,
	unsigned &maxOptionalNumArgs)
	{
	const MachineFrameInfo& frameInfo = target.getFrameInfo();

	unsigned maxSize = 0;

	for (Function::const_iterator BB = F->begin(), BBE = F->end(); BB !=BBE; ++BB)
	for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I)
	if (const CallInst callInst = dyn_cast<CallInst>(&I))
	{
	unsigned numOperands = callInst->getNumOperands() - 1;
	int numExtra = (int)numOperands-frameInfo.getNumFixedOutgoingArgs();
	if (numExtra <= 0)
	continue;

	unsigned int sizeForThisCall;
	if (frameInfo.argsOnStackHaveFixedSize())
	{
	int argSize = frameInfo.getSizeOfEachArgOnStack();
	sizeForThisCall = numExtra * (unsigned) argSize;
	}
	else
	{
	assert(0 && "UNTESTED CODE: Size per stack argument is not "
	"fixed on this architecture: use actual arg sizes to "
	"compute MaxOptionalArgsSize");
	sizeForThisCall = 0;
	for (unsigned i = 0; i < numOperands; ++i)
	sizeForThisCall += target.DataLayout.getTypeSize(callInst->
	getOperand(i)->getType());
	}

	if (maxSize < sizeForThisCall)
	maxSize = sizeForThisCall;

	if ((int)maxOptionalNumArgs < numExtra)
	maxOptionalNumArgs = (unsigned) numExtra;
	}

	return maxSize;
	}

	// Align data larger than one L1 cache line on L1 cache line boundaries.
	// Align all smaller data on the next higher 2^x boundary (4, 8, ...),
	// but not higher than the alignment of the largest type we support
	// (currently a double word). -- see class TargetData).
	//
	// This function is similar to the corresponding function in EmitAssembly.cpp
	// but they are unrelated. This one does not align at more than a
	// double-word boundary whereas that one might.
	//
	inline unsigned int
	SizeToAlignment(unsigned int size, const TargetMachine& target)
	{
	unsigned short cacheLineSize = target.getCacheInfo().getCacheLineSize(1);
	if (size > (unsigned) cacheLineSize / 2)
	return cacheLineSize;
	else
	for (unsigned sz=1; /no condition/; sz *= 2)
	if (sz >= size \|\| sz >= target.DataLayout.getDoubleAlignment())
	return sz;
	}


	/ctor/
	MachineFunction::MachineFunction(const Function *F,
	const TargetMachine& target)
	: Annotation(MCFM_AID),
	Fn(F), Target(target), staticStackSize(0),
	automaticVarsSize(0), regSpillsSize(0),
	maxOptionalArgsSize(0), maxOptionalNumArgs(0),
	currentTmpValuesSize(0), maxTmpValuesSize(0), compiledAsLeaf(false),
	spillsAreaFrozen(false), automaticVarsAreaFrozen(false)
	{
	maxOptionalArgsSize = ComputeMaxOptionalArgsSize(target, Fn,
	maxOptionalNumArgs);
	staticStackSize = maxOptionalArgsSize
	+ target.getFrameInfo().getMinStackFrameSize();
	}

	int
	MachineFunction::computeOffsetforLocalVar(const TargetMachine& target,
	const Value* val,
	unsigned int& getPaddedSize,
	unsigned int sizeToUse)
	{
	if (sizeToUse == 0)
	sizeToUse = target.findOptimalStorageSize(val->getType());
	unsigned int align = SizeToAlignment(sizeToUse, target);

	bool growUp;
	int firstOffset = target.getFrameInfo().getFirstAutomaticVarOffset(*this,
	growUp);
	int offset = growUp? firstOffset + getAutomaticVarsSize()
	: firstOffset - (getAutomaticVarsSize() + sizeToUse);

	int aligned = target.getFrameInfo().adjustAlignment(offset, growUp, align);
	getPaddedSize = sizeToUse + abs(aligned - offset);

	return aligned;
	}

	int
	MachineFunction::allocateLocalVar(const TargetMachine& target,
	const Value* val,
	unsigned int sizeToUse)
	{
	assert(! automaticVarsAreaFrozen &&
	"Size of auto vars area has been used to compute an offset so "
	"no more automatic vars should be allocated!");

	// Check if we've allocated a stack slot for this value already
	//
	int offset = getOffset(val);
	if (offset == INVALID_FRAME_OFFSET)
	{
	unsigned int getPaddedSize;
	offset = computeOffsetforLocalVar(target, val, getPaddedSize, sizeToUse);
	offsets[val] = offset;
	incrementAutomaticVarsSize(getPaddedSize);
	}
	return offset;
	}

	int
	MachineFunction::allocateSpilledValue(const TargetMachine& target,
	const Type* type)
	{
	assert(! spillsAreaFrozen &&
	"Size of reg spills area has been used to compute an offset so "
	"no more register spill slots should be allocated!");

	unsigned int size = target.DataLayout.getTypeSize(type);
	unsigned char align = target.DataLayout.getTypeAlignment(type);

	bool growUp;
	int firstOffset = target.getFrameInfo().getRegSpillAreaOffset(*this, growUp);

	int offset = growUp? firstOffset + getRegSpillsSize()
	: firstOffset - (getRegSpillsSize() + size);

	int aligned = target.getFrameInfo().adjustAlignment(offset, growUp, align);
	size += abs(aligned - offset); // include alignment padding in size

	incrementRegSpillsSize(size); // update size of reg. spills area

	return aligned;
	}

	int
	MachineFunction::pushTempValue(const TargetMachine& target,
	unsigned int size)
	{
	unsigned int align = SizeToAlignment(size, target);

	bool growUp;
	int firstOffset = target.getFrameInfo().getTmpAreaOffset(*this, growUp);

	int offset = growUp? firstOffset + currentTmpValuesSize
	: firstOffset - (currentTmpValuesSize + size);

	int aligned = target.getFrameInfo().adjustAlignment(offset, growUp, align);
	size += abs(aligned - offset); // include alignment padding in size

	incrementTmpAreaSize(size); // update "current" size of tmp area

	return aligned;
	}

	void
	MachineFunction::popAllTempValues(const TargetMachine& target)
	{
	resetTmpAreaSize(); // clear tmp area to reuse
	}

	int
	MachineFunction::getOffset(const Value* val) const
	{
	hash_map<const Value*, int>::const_iterator pair = offsets.find(val);
	return (pair == offsets.end()) ? INVALID_FRAME_OFFSET : pair->second;
	}

	void
	MachineFunction::dump() const
	{
	std::cerr << "\n" << Fn->getReturnType()
	<< " \"" << Fn->getName() << "\"\n";

	for (const_iterator BB = begin(); BB != end(); ++BB) {
	std::cerr << "\n" << BB->getBasicBlock()->getName() << " ("
	<< (const void*)BB->getBasicBlock() << ")" << ":" << "\n";
	for (MachineBasicBlock::const_iterator I = BB->begin(); I != BB->end(); ++I)
	std::cerr << "\t" << *I;
	}
	std::cerr << "\nEnd function \"" << Fn->getName() << "\"\n\n";
	}