llvm-project/llvm/lib/Target/AMDGPU/SIFixControlFlowLiveInterva...

97 lines
2.8 KiB
C++

//===-- SIFixControlFlowLiveIntervals.cpp - Fix CF live intervals ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
/// \file
/// \brief Spilling of EXEC masks used for control flow messes up control flow
/// lowering, so mark all live intervals associated with CF instructions as
/// non-spillable.
///
//===----------------------------------------------------------------------===//
#include "AMDGPU.h"
#include "SIInstrInfo.h"
#include "SIRegisterInfo.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachinePostDominators.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;
#define DEBUG_TYPE "si-fix-cf-live-intervals"
namespace {
class SIFixControlFlowLiveIntervals : public MachineFunctionPass {
public:
static char ID;
public:
SIFixControlFlowLiveIntervals() : MachineFunctionPass(ID) {
initializeSIFixControlFlowLiveIntervalsPass(*PassRegistry::getPassRegistry());
}
bool runOnMachineFunction(MachineFunction &MF) override;
const char *getPassName() const override {
return "SI Fix CF Live Intervals";
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<LiveIntervals>();
AU.setPreservesAll();
MachineFunctionPass::getAnalysisUsage(AU);
}
};
} // End anonymous namespace.
INITIALIZE_PASS_BEGIN(SIFixControlFlowLiveIntervals, DEBUG_TYPE,
"SI Fix CF Live Intervals", false, false)
INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
INITIALIZE_PASS_END(SIFixControlFlowLiveIntervals, DEBUG_TYPE,
"SI Fix CF Live Intervals", false, false)
char SIFixControlFlowLiveIntervals::ID = 0;
char &llvm::SIFixControlFlowLiveIntervalsID = SIFixControlFlowLiveIntervals::ID;
FunctionPass *llvm::createSIFixControlFlowLiveIntervalsPass() {
return new SIFixControlFlowLiveIntervals();
}
bool SIFixControlFlowLiveIntervals::runOnMachineFunction(MachineFunction &MF) {
LiveIntervals *LIS = &getAnalysis<LiveIntervals>();
for (const MachineBasicBlock &MBB : MF) {
for (const MachineInstr &MI : MBB) {
switch (MI.getOpcode()) {
case AMDGPU::SI_IF:
case AMDGPU::SI_ELSE:
case AMDGPU::SI_BREAK:
case AMDGPU::SI_IF_BREAK:
case AMDGPU::SI_ELSE_BREAK:
case AMDGPU::SI_END_CF: {
unsigned Reg = MI.getOperand(0).getReg();
LIS->getInterval(Reg).markNotSpillable();
break;
}
default:
break;
}
}
}
return false;
}