llvm-6502/lib/Target/XCore/XCoreFrameToArgsOffsetElim.cpp
Eric Christopher 6035518e3b Have MachineFunction cache a pointer to the subtarget to make lookups
shorter/easier and have the DAG use that to do the same lookup. This
can be used in the future for TargetMachine based caching lookups from
the MachineFunction easily.

Update the MIPS subtarget switching machinery to update this pointer
at the same time it runs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214838 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-05 02:39:49 +00:00

64 lines
2.1 KiB
C++

//===-- XCoreFrameToArgsOffsetElim.cpp ----------------------------*- C++ -*-=//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Replace Pseudo FRAME_TO_ARGS_OFFSET with the appropriate real offset.
//
//===----------------------------------------------------------------------===//
#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;
}
/// createXCoreFrameToArgsOffsetEliminationPass - returns an instance of the
/// Frame to args offset elimination pass
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;
}