XCoreFrameToArgsOffsetElim.cpp [plain text]
#include "XCore.h"
#include "XCoreInstrInfo.h"
#include "XCoreSubtarget.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;
namespace {
struct XCoreFTAOElim : public MachineFunctionPass {
static char ID;
XCoreFTAOElim() : MachineFunctionPass(ID) {}
bool runOnMachineFunction(MachineFunction &Fn) override;
const char *getPassName() const override {
return "XCore FRAME_TO_ARGS_OFFSET Elimination";
}
};
char XCoreFTAOElim::ID = 0;
}
FunctionPass *llvm::createXCoreFrameToArgsOffsetEliminationPass() {
return new XCoreFTAOElim();
}
bool XCoreFTAOElim::runOnMachineFunction(MachineFunction &MF) {
const XCoreInstrInfo &TII =
*static_cast<const XCoreInstrInfo *>(MF.getSubtarget().getInstrInfo());
unsigned StackSize = MF.getFrameInfo()->getStackSize();
for (MachineFunction::iterator MFI = MF.begin(), E = MF.end(); MFI != E;
++MFI) {
MachineBasicBlock &MBB = *MFI;
for (MachineBasicBlock::iterator MBBI = MBB.begin(), EE = MBB.end();
MBBI != EE; ++MBBI) {
if (MBBI->getOpcode() == XCore::FRAME_TO_ARGS_OFFSET) {
MachineInstr *OldInst = MBBI;
unsigned Reg = OldInst->getOperand(0).getReg();
MBBI = TII.loadImmediate(MBB, MBBI, Reg, StackSize);
OldInst->eraseFromParent();
}
}
}
return true;
}