#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
INITIALIZE_PASS_BEGIN(AArch64ConditionOptimizer, "aarch64-condopt",
"AArch64 CondOpt Pass", false, false)
INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
+INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
INITIALIZE_PASS_END(AArch64ConditionOptimizer, "aarch64-condopt",
"AArch64 CondOpt Pass", false, false)
void AArch64ConditionOptimizer::getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<MachineDominatorTree>();
AU.addPreserved<MachineDominatorTree>();
+ AU.addRequired<LiveIntervals>();
+ AU.addPreserved<LiveIntervals>();
MachineFunctionPass::getAnalysisUsage(AU);
}
MachineInstr *AArch64ConditionOptimizer::findSuitableCompare(
MachineBasicBlock *MBB) {
MachineBasicBlock::iterator I = MBB->getFirstTerminator();
- if (I == MBB->end()) {
+ if (I == MBB->end())
return nullptr;
- }
- if (I->getOpcode() != AArch64::Bcc) {
- return nullptr;
- }
+ if (I->getOpcode() != AArch64::Bcc)
+ return nullptr;
// Now find the instruction controlling the terminator.
for (MachineBasicBlock::iterator B = MBB->begin(); I != B;) {
// cmn is an alias for adds with a dead destination register.
case AArch64::ADDSWri:
case AArch64::ADDSXri:
- return I;
+ if (I->getOperand(0).isDead())
+ return I;
+
+ DEBUG(dbgs() << "Destination of cmp is not dead, " << *I << '\n');
+ return nullptr;
// Prevent false positive case like:
// cmp w19, #0