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-rw-r--r--lib/CodeGen/BranchFolding.cpp66
1 files changed, 42 insertions, 24 deletions
diff --git a/lib/CodeGen/BranchFolding.cpp b/lib/CodeGen/BranchFolding.cpp
index 89894c3..59c92b3 100644
--- a/lib/CodeGen/BranchFolding.cpp
+++ b/lib/CodeGen/BranchFolding.cpp
@@ -61,29 +61,33 @@ TailMergeSize("tail-merge-size",
namespace {
/// BranchFolderPass - Wrap branch folder in a machine function pass.
- class BranchFolderPass : public MachineFunctionPass,
- public BranchFolder {
+ class BranchFolderPass : public MachineFunctionPass {
public:
static char ID;
- explicit BranchFolderPass(bool defaultEnableTailMerge)
- : MachineFunctionPass(ID), BranchFolder(defaultEnableTailMerge, true) {}
+ explicit BranchFolderPass(): MachineFunctionPass(ID) {}
virtual bool runOnMachineFunction(MachineFunction &MF);
- virtual const char *getPassName() const { return "Control Flow Optimizer"; }
+
+ virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.addRequired<TargetPassConfig>();
+ MachineFunctionPass::getAnalysisUsage(AU);
+ }
};
}
char BranchFolderPass::ID = 0;
+char &llvm::BranchFolderPassID = BranchFolderPass::ID;
-FunctionPass *llvm::createBranchFoldingPass(bool DefaultEnableTailMerge) {
- return new BranchFolderPass(DefaultEnableTailMerge);
-}
+INITIALIZE_PASS(BranchFolderPass, "branch-folder",
+ "Control Flow Optimizer", false, false)
bool BranchFolderPass::runOnMachineFunction(MachineFunction &MF) {
- return OptimizeFunction(MF,
- MF.getTarget().getInstrInfo(),
- MF.getTarget().getRegisterInfo(),
- getAnalysisIfAvailable<MachineModuleInfo>());
+ TargetPassConfig *PassConfig = &getAnalysis<TargetPassConfig>();
+ BranchFolder Folder(PassConfig->getEnableTailMerge(), /*CommonHoist=*/true);
+ return Folder.OptimizeFunction(MF,
+ MF.getTarget().getInstrInfo(),
+ MF.getTarget().getRegisterInfo(),
+ getAnalysisIfAvailable<MachineModuleInfo>());
}
@@ -132,7 +136,7 @@ bool BranchFolder::OptimizeImpDefsBlock(MachineBasicBlock *MBB) {
break;
unsigned Reg = I->getOperand(0).getReg();
ImpDefRegs.insert(Reg);
- for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
+ for (const uint16_t *SubRegs = TRI->getSubRegisters(Reg);
unsigned SubReg = *SubRegs; ++SubRegs)
ImpDefRegs.insert(SubReg);
++I;
@@ -208,7 +212,7 @@ bool BranchFolder::OptimizeFunction(MachineFunction &MF,
delete RS;
return MadeChange;
}
-
+
// Walk the function to find jump tables that are live.
BitVector JTIsLive(JTI->getJumpTables().size());
for (MachineFunction::iterator BB = MF.begin(), E = MF.end();
@@ -483,8 +487,9 @@ BranchFolder::MergePotentialsElt::operator<(const MergePotentialsElt &o) const {
// an object with itself.
#ifndef _GLIBCXX_DEBUG
llvm_unreachable("Predecessor appears twice");
-#endif
+#else
return false;
+#endif
}
}
@@ -1094,7 +1099,7 @@ ReoptimizeBlock:
MachineBasicBlock::iterator PrevBBIter = PrevBB.end();
--PrevBBIter;
MachineBasicBlock::iterator MBBIter = MBB->begin();
- // Check if DBG_VALUE at the end of PrevBB is identical to the
+ // Check if DBG_VALUE at the end of PrevBB is identical to the
// DBG_VALUE at the beginning of MBB.
while (PrevBBIter != PrevBB.begin() && MBBIter != MBB->end()
&& PrevBBIter->isDebugValue() && MBBIter->isDebugValue()) {
@@ -1106,7 +1111,7 @@ ReoptimizeBlock:
}
}
PrevBB.splice(PrevBB.end(), MBB, MBB->begin(), MBB->end());
- PrevBB.removeSuccessor(PrevBB.succ_begin());;
+ PrevBB.removeSuccessor(PrevBB.succ_begin());
assert(PrevBB.succ_empty());
PrevBB.transferSuccessors(MBB);
MadeChange = true;
@@ -1449,7 +1454,7 @@ MachineBasicBlock::iterator findHoistingInsertPosAndDeps(MachineBasicBlock *MBB,
continue;
if (MO.isUse()) {
Uses.insert(Reg);
- for (const unsigned *AS = TRI->getAliasSet(Reg); *AS; ++AS)
+ for (const uint16_t *AS = TRI->getAliasSet(Reg); *AS; ++AS)
Uses.insert(*AS);
} else if (!MO.isDead())
// Don't try to hoist code in the rare case the terminator defines a
@@ -1472,6 +1477,9 @@ MachineBasicBlock::iterator findHoistingInsertPosAndDeps(MachineBasicBlock *MBB,
bool IsDef = false;
for (unsigned i = 0, e = PI->getNumOperands(); !IsDef && i != e; ++i) {
const MachineOperand &MO = PI->getOperand(i);
+ // If PI has a regmask operand, it is probably a call. Separate away.
+ if (MO.isRegMask())
+ return Loc;
if (!MO.isReg() || MO.isUse())
continue;
unsigned Reg = MO.getReg();
@@ -1508,16 +1516,16 @@ MachineBasicBlock::iterator findHoistingInsertPosAndDeps(MachineBasicBlock *MBB,
continue;
if (MO.isUse()) {
Uses.insert(Reg);
- for (const unsigned *AS = TRI->getAliasSet(Reg); *AS; ++AS)
+ for (const uint16_t *AS = TRI->getAliasSet(Reg); *AS; ++AS)
Uses.insert(*AS);
} else {
if (Uses.count(Reg)) {
Uses.erase(Reg);
- for (const unsigned *SR = TRI->getSubRegisters(Reg); *SR; ++SR)
+ for (const uint16_t *SR = TRI->getSubRegisters(Reg); *SR; ++SR)
Uses.erase(*SR); // Use getSubRegisters to be conservative
}
Defs.insert(Reg);
- for (const unsigned *AS = TRI->getAliasSet(Reg); *AS; ++AS)
+ for (const uint16_t *AS = TRI->getAliasSet(Reg); *AS; ++AS)
Defs.insert(*AS);
}
}
@@ -1584,6 +1592,11 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) {
bool IsSafe = true;
for (unsigned i = 0, e = TIB->getNumOperands(); i != e; ++i) {
MachineOperand &MO = TIB->getOperand(i);
+ // Don't attempt to hoist instructions with register masks.
+ if (MO.isRegMask()) {
+ IsSafe = false;
+ break;
+ }
if (!MO.isReg())
continue;
unsigned Reg = MO.getReg();
@@ -1618,6 +1631,11 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) {
IsSafe = false;
break;
}
+
+ if (MO.isKill() && Uses.count(Reg))
+ // Kills a register that's read by the instruction at the point of
+ // insertion. Remove the kill marker.
+ MO.setIsKill(false);
}
}
if (!IsSafe)
@@ -1635,7 +1653,7 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) {
unsigned Reg = MO.getReg();
if (!Reg || !LocalDefsSet.count(Reg))
continue;
- for (const unsigned *OR = TRI->getOverlaps(Reg); *OR; ++OR)
+ for (const uint16_t *OR = TRI->getOverlaps(Reg); *OR; ++OR)
LocalDefsSet.erase(*OR);
}
@@ -1648,11 +1666,11 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) {
if (!Reg)
continue;
LocalDefs.push_back(Reg);
- for (const unsigned *OR = TRI->getOverlaps(Reg); *OR; ++OR)
+ for (const uint16_t *OR = TRI->getOverlaps(Reg); *OR; ++OR)
LocalDefsSet.insert(*OR);
}
- HasDups = true;;
+ HasDups = true;
++TIB;
++FIB;
}
generated by cgit v1.1 at 2025-08-17 03:39:34 +0000