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-rw-r--r--contrib/llvm/lib/CodeGen/MachineSink.cpp28
1 files changed, 24 insertions, 4 deletions
diff --git a/contrib/llvm/lib/CodeGen/MachineSink.cpp b/contrib/llvm/lib/CodeGen/MachineSink.cpp
index 8337793..aed0e50 100644
--- a/contrib/llvm/lib/CodeGen/MachineSink.cpp
+++ b/contrib/llvm/lib/CodeGen/MachineSink.cpp
@@ -19,6 +19,7 @@
#include "llvm/CodeGen/Passes.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/SparseBitVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
@@ -70,6 +71,8 @@ namespace {
// will be split.
SetVector<std::pair<MachineBasicBlock*,MachineBasicBlock*> > ToSplit;
+ SparseBitVector<> RegsToClearKillFlags;
+
public:
static char ID; // Pass identification
MachineSinking() : MachineFunctionPass(ID) {
@@ -287,6 +290,12 @@ bool MachineSinking::runOnMachineFunction(MachineFunction &MF) {
if (!MadeChange) break;
EverMadeChange = true;
}
+
+ // Now clear any kill flags for recorded registers.
+ for (auto I : RegsToClearKillFlags)
+ MRI->clearKillFlags(I);
+ RegsToClearKillFlags.clear();
+
return EverMadeChange;
}
@@ -643,7 +652,11 @@ bool MachineSinking::SinkInstruction(MachineInstr *MI, bool &SawStore) {
return false;
// Check if it's safe to move the instruction.
- if (!MI->isSafeToMove(TII, AA, SawStore))
+ if (!MI->isSafeToMove(AA, SawStore))
+ return false;
+
+ // Convergent operations may only be moved to control equivalent locations.
+ if (MI->isConvergent())
return false;
// FIXME: This should include support for sinking instructions within the
@@ -656,7 +669,8 @@ bool MachineSinking::SinkInstruction(MachineInstr *MI, bool &SawStore) {
bool BreakPHIEdge = false;
MachineBasicBlock *ParentBlock = MI->getParent();
- MachineBasicBlock *SuccToSinkTo = FindSuccToSinkTo(MI, ParentBlock, BreakPHIEdge);
+ MachineBasicBlock *SuccToSinkTo = FindSuccToSinkTo(MI, ParentBlock,
+ BreakPHIEdge);
// If there are no outputs, it must have side-effects.
if (!SuccToSinkTo)
@@ -684,7 +698,7 @@ bool MachineSinking::SinkInstruction(MachineInstr *MI, bool &SawStore) {
// other code paths.
bool TryBreak = false;
bool store = true;
- if (!MI->isSafeToMove(TII, AA, store)) {
+ if (!MI->isSafeToMove(AA, store)) {
DEBUG(dbgs() << " *** NOTE: Won't sink load along critical edge.\n");
TryBreak = true;
}
@@ -755,7 +769,13 @@ bool MachineSinking::SinkInstruction(MachineInstr *MI, bool &SawStore) {
// Conservatively, clear any kill flags, since it's possible that they are no
// longer correct.
- MI->clearKillInfo();
+ // Note that we have to clear the kill flags for any register this instruction
+ // uses as we may sink over another instruction which currently kills the
+ // used registers.
+ for (MachineOperand &MO : MI->operands()) {
+ if (MO.isReg() && MO.isUse())
+ RegsToClearKillFlags.set(MO.getReg()); // Remember to clear kill flags.
+ }
return true;
}
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