llvm-6502/lib/Transforms/Utils/CloneFunction.cpp

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// FIXME: document
#include "llvm/Transforms/CloneFunction.h"
#include "llvm/Function.h"
#include "llvm/BasicBlock.h"
#include "llvm/Instruction.h"
#include <map>
// FIXME: This should be merged with MethodInlining
// RemapInstruction - Convert the instruction operands from referencing the
// current values into those specified by ValueMap.
//
static inline void RemapInstruction(Instruction *I,
std::map<const Value *, Value*> &ValueMap) {
for (unsigned op = 0, E = I->getNumOperands(); op != E; ++op) {
const Value *Op = I->getOperand(op);
Value *V = ValueMap[Op];
if (!V && (isa<GlobalValue>(Op) || isa<Constant>(Op)))
continue; // Globals and constants don't get relocated
#ifndef NDEBUG
if (!V) {
cerr << "Val = \n" << Op << "Addr = " << (void*)Op;
cerr << "\nInst = " << I;
}
#endif
assert(V && "Referenced value not in value map!");
I->setOperand(op, V);
}
}
// Clone OldFunc into NewFunc, transforming the old arguments into references to
// ArgMap values.
//
void CloneFunctionInto(Function *NewFunc, const Function *OldFunc,
const std::vector<Value*> &ArgMap) {
assert(OldFunc->getArgumentList().empty() ||
!NewFunc->getArgumentList().empty() &&
"Synthesization of arguments is not implemented yet!");
assert(OldFunc->getArgumentList().size() == ArgMap.size() &&
"Improper number of argument values to map specified!");
// Keep a mapping between the original function's values and the new
// duplicated code's values. This includes all of: Function arguments,
// instruction values, constant pool entries, and basic blocks.
//
std::map<const Value *, Value*> ValueMap;
// Add all of the function arguments to the mapping...
for (unsigned i = 0, e = ArgMap.size(); i != e; ++i)
ValueMap[(Value*)OldFunc->getArgumentList()[i]] = ArgMap[i];
// Loop over all of the basic blocks in the function, cloning them as
// appropriate.
//
for (Function::const_iterator BI = OldFunc->begin(), BE = OldFunc->end();
BI != BE; ++BI) {
const BasicBlock *BB = *BI;
assert(BB->getTerminator() && "BasicBlock doesn't have terminator!?!?");
// Create a new basic block to copy instructions into!
BasicBlock *CBB = new BasicBlock(BB->getName(), NewFunc);
ValueMap[BB] = CBB; // Add basic block mapping.
// Loop over all instructions copying them over...
for (BasicBlock::const_iterator II = BB->begin(), IE = BB->end();
II != IE; ++II) {
Instruction *NewInst = (*II)->clone();
NewInst->setName((*II)->getName()); // Name is not cloned...
CBB->getInstList().push_back(NewInst);
ValueMap[*II] = NewInst; // Add instruction map to value.
}
}
// Loop over all of the instructions in the function, fixing up operand
// references as we go. This uses ValueMap to do all the hard work.
//
for (Function::const_iterator BI = OldFunc->begin(), BE = OldFunc->end();
BI != BE; ++BI) {
const BasicBlock *BB = *BI;
BasicBlock *NBB = cast<BasicBlock>(ValueMap[BB]);
// Loop over all instructions, fixing each one as we find it...
for (BasicBlock::iterator II = NBB->begin(); II != NBB->end(); II++)
RemapInstruction(*II, ValueMap);
}
}