Spill slots cannot alias.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84432 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/PseudoSourceValue.cpp b/lib/CodeGen/PseudoSourceValue.cpp
index 289a52b..70e8640 100644
--- a/lib/CodeGen/PseudoSourceValue.cpp
+++ b/lib/CodeGen/PseudoSourceValue.cpp
@@ -63,7 +63,7 @@
virtual bool isConstant(const MachineFrameInfo *MFI) const;
- virtual bool isAliased() const;
+ virtual bool isAliased(const MachineFrameInfo *MFI) const;
virtual void printCustom(raw_ostream &OS) const {
OS << "FixedStack" << FI;
@@ -91,7 +91,7 @@
return false;
}
-bool PseudoSourceValue::isAliased() const {
+bool PseudoSourceValue::isAliased(const MachineFrameInfo *MFI) const {
if (this == getStack() ||
this == getGOT() ||
this == getConstantPool() ||
@@ -105,9 +105,12 @@
return MFI && MFI->isImmutableObjectIndex(FI);
}
-bool FixedStackPseudoSourceValue::isAliased() const{
+bool FixedStackPseudoSourceValue::isAliased(const MachineFrameInfo *MFI) const {
// Negative frame indices are used for special things that don't
// appear in LLVM IR. Non-negative indices may be used for things
// like static allocas.
- return FI >= 0;
+ if (!MFI)
+ return FI >= 0;
+ // Spill slots should not alias others.
+ return !MFI->isFixedObjectIndex(FI) && !MFI->isSpillSlotObjectIndex(FI);
}
diff --git a/lib/CodeGen/ScheduleDAGInstrs.cpp b/lib/CodeGen/ScheduleDAGInstrs.cpp
index 768ca16..43454dd 100644
--- a/lib/CodeGen/ScheduleDAGInstrs.cpp
+++ b/lib/CodeGen/ScheduleDAGInstrs.cpp
@@ -32,7 +32,9 @@
ScheduleDAGInstrs::ScheduleDAGInstrs(MachineFunction &mf,
const MachineLoopInfo &mli,
const MachineDominatorTree &mdt)
- : ScheduleDAG(mf), MLI(mli), MDT(mdt), LoopRegs(MLI, MDT) {}
+ : ScheduleDAG(mf), MLI(mli), MDT(mdt), LoopRegs(MLI, MDT) {
+ MFI = mf.getFrameInfo();
+}
/// Run - perform scheduling.
///
@@ -95,7 +97,8 @@
/// getUnderlyingObjectForInstr - If this machine instr has memory reference
/// information and it can be tracked to a normal reference to a known
/// object, return the Value for that object. Otherwise return null.
-static const Value *getUnderlyingObjectForInstr(const MachineInstr *MI) {
+static const Value *getUnderlyingObjectForInstr(const MachineInstr *MI,
+ const MachineFrameInfo *MFI) {
if (!MI->hasOneMemOperand() ||
!(*MI->memoperands_begin())->getValue() ||
(*MI->memoperands_begin())->isVolatile())
@@ -110,7 +113,7 @@
// For now, ignore PseudoSourceValues which may alias LLVM IR values
// because the code that uses this function has no way to cope with
// such aliases.
- if (PSV->isAliased())
+ if (PSV->isAliased(MFI))
return 0;
return V;
}
@@ -353,7 +356,7 @@
// Unknown memory accesses. Assume the worst.
ChainMMO = 0;
} else if (TID.mayStore()) {
- if (const Value *V = getUnderlyingObjectForInstr(MI)) {
+ if (const Value *V = getUnderlyingObjectForInstr(MI, MFI)) {
// A store to a specific PseudoSourceValue. Add precise dependencies.
// Handle the def in MemDefs, if there is one.
std::map<const Value *, SUnit *>::iterator I = MemDefs.find(V);
@@ -386,7 +389,7 @@
} else if (TID.mayLoad()) {
if (MI->isInvariantLoad(AA)) {
// Invariant load, no chain dependencies needed!
- } else if (const Value *V = getUnderlyingObjectForInstr(MI)) {
+ } else if (const Value *V = getUnderlyingObjectForInstr(MI, MFI)) {
// A load from a specific PseudoSourceValue. Add precise dependencies.
std::map<const Value *, SUnit *>::iterator I = MemDefs.find(V);
if (I != MemDefs.end())
diff --git a/lib/CodeGen/ScheduleDAGInstrs.h b/lib/CodeGen/ScheduleDAGInstrs.h
index 29e1c98..366c3a8 100644
--- a/lib/CodeGen/ScheduleDAGInstrs.h
+++ b/lib/CodeGen/ScheduleDAGInstrs.h
@@ -98,6 +98,7 @@
class VISIBILITY_HIDDEN ScheduleDAGInstrs : public ScheduleDAG {
const MachineLoopInfo &MLI;
const MachineDominatorTree &MDT;
+ const MachineFrameInfo *MFI;
/// Defs, Uses - Remember where defs and uses of each physical register
/// are as we iterate upward through the instructions. This is allocated