llvm-project/llvm/lib/Target/AMDGPU/SIFixVGPRCopies.cpp

72 lines
2.0 KiB
C++

//===-- SIFixVGPRCopies.cpp - Fix VGPR Copies after regalloc --------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
/// \file
/// Add implicit use of exec to vector register copies.
///
//===----------------------------------------------------------------------===//
#include "AMDGPU.h"
#include "GCNSubtarget.h"
#include "MCTargetDesc/AMDGPUMCTargetDesc.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
using namespace llvm;
#define DEBUG_TYPE "si-fix-vgpr-copies"
namespace {
class SIFixVGPRCopies : public MachineFunctionPass {
public:
static char ID;
public:
SIFixVGPRCopies() : MachineFunctionPass(ID) {
initializeSIFixVGPRCopiesPass(*PassRegistry::getPassRegistry());
}
bool runOnMachineFunction(MachineFunction &MF) override;
StringRef getPassName() const override { return "SI Fix VGPR copies"; }
};
} // End anonymous namespace.
INITIALIZE_PASS(SIFixVGPRCopies, DEBUG_TYPE, "SI Fix VGPR copies", false, false)
char SIFixVGPRCopies::ID = 0;
char &llvm::SIFixVGPRCopiesID = SIFixVGPRCopies::ID;
bool SIFixVGPRCopies::runOnMachineFunction(MachineFunction &MF) {
const GCNSubtarget &ST = MF.getSubtarget<GCNSubtarget>();
const SIRegisterInfo *TRI = ST.getRegisterInfo();
const SIInstrInfo *TII = ST.getInstrInfo();
bool Changed = false;
for (MachineBasicBlock &MBB : MF) {
for (MachineInstr &MI : MBB) {
switch (MI.getOpcode()) {
case AMDGPU::COPY:
if (TII->isVGPRCopy(MI) && !MI.readsRegister(AMDGPU::EXEC, TRI)) {
MI.addOperand(MF,
MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
LLVM_DEBUG(dbgs() << "Add exec use to " << MI);
Changed = true;
}
break;
default:
break;
}
}
}
return Changed;
}