NVPTXLowerAlloca.cpp [plain text]
#include "NVPTX.h"
#include "NVPTXUtilities.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/Pass.h"
using namespace llvm;
namespace llvm {
void initializeNVPTXLowerAllocaPass(PassRegistry &);
}
namespace {
class NVPTXLowerAlloca : public BasicBlockPass {
bool runOnBasicBlock(BasicBlock &BB) override;
public:
static char ID; NVPTXLowerAlloca() : BasicBlockPass(ID) {}
const char *getPassName() const override {
return "convert address space of alloca'ed memory to local";
}
};
}
char NVPTXLowerAlloca::ID = 1;
INITIALIZE_PASS(NVPTXLowerAlloca, "nvptx-lower-alloca",
"Lower Alloca", false, false)
bool NVPTXLowerAlloca::runOnBasicBlock(BasicBlock &BB) {
bool Changed = false;
for (auto &I : BB) {
if (auto allocaInst = dyn_cast<AllocaInst>(&I)) {
Changed = true;
auto PTy = dyn_cast<PointerType>(allocaInst->getType());
auto ETy = PTy->getElementType();
auto LocalAddrTy = PointerType::get(ETy, ADDRESS_SPACE_LOCAL);
auto NewASCToLocal = new AddrSpaceCastInst(allocaInst, LocalAddrTy, "");
auto GenericAddrTy = PointerType::get(ETy, ADDRESS_SPACE_GENERIC);
auto NewASCToGeneric = new AddrSpaceCastInst(NewASCToLocal,
GenericAddrTy, "");
NewASCToLocal->insertAfter(allocaInst);
NewASCToGeneric->insertAfter(NewASCToLocal);
for (Value::use_iterator UI = allocaInst->use_begin(),
UE = allocaInst->use_end();
UI != UE; ) {
const auto &AllocaUse = *UI++;
auto LI = dyn_cast<LoadInst>(AllocaUse.getUser());
if (LI && LI->getPointerOperand() == allocaInst && !LI->isVolatile()) {
LI->setOperand(LI->getPointerOperandIndex(), NewASCToGeneric);
continue;
}
auto SI = dyn_cast<StoreInst>(AllocaUse.getUser());
if (SI && SI->getPointerOperand() == allocaInst && !SI->isVolatile()) {
SI->setOperand(SI->getPointerOperandIndex(), NewASCToGeneric);
continue;
}
auto GI = dyn_cast<GetElementPtrInst>(AllocaUse.getUser());
if (GI && GI->getPointerOperand() == allocaInst) {
GI->setOperand(GI->getPointerOperandIndex(), NewASCToGeneric);
continue;
}
auto BI = dyn_cast<BitCastInst>(AllocaUse.getUser());
if (BI && BI->getOperand(0) == allocaInst) {
BI->setOperand(0, NewASCToGeneric);
continue;
}
}
}
}
return Changed;
}
BasicBlockPass *llvm::createNVPTXLowerAllocaPass() {
return new NVPTXLowerAlloca();
}