Replace X86's CanRematLoadWithDispOperand by calling the target-independent
MachineInstr::isInvariantLoad instead, which has the benefit of being
more complete.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83696 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86InstrInfo.cpp b/lib/Target/X86/X86InstrInfo.cpp
index 6558df0..56de6d9 100644
--- a/lib/Target/X86/X86InstrInfo.cpp
+++ b/lib/Target/X86/X86InstrInfo.cpp
@@ -782,31 +782,9 @@
return isPICBase;
}
-/// CanRematLoadWithDispOperand - Return true if a load with the specified
-/// operand is a candidate for remat: for this to be true we need to know that
-/// the load will always return the same value, even if moved.
-static bool CanRematLoadWithDispOperand(const MachineOperand &MO,
- X86TargetMachine &TM) {
- // Loads from constant pool entries can be remat'd.
- if (MO.isCPI()) return true;
-
- // We can remat globals in some cases.
- if (MO.isGlobal()) {
- // If this is a load of a stub, not of the global, we can remat it. This
- // access will always return the address of the global.
- if (isGlobalStubReference(MO.getTargetFlags()))
- return true;
-
- // If the global itself is constant, we can remat the load.
- if (GlobalVariable *GV = dyn_cast<GlobalVariable>(MO.getGlobal()))
- if (GV->isConstant())
- return true;
- }
- return false;
-}
-
bool
-X86InstrInfo::isReallyTriviallyReMaterializable(const MachineInstr *MI) const {
+X86InstrInfo::isReallyTriviallyReMaterializable(const MachineInstr *MI,
+ AliasAnalysis *AA) const {
switch (MI->getOpcode()) {
default: break;
case X86::MOV8rm:
@@ -825,7 +803,7 @@
if (MI->getOperand(1).isReg() &&
MI->getOperand(2).isImm() &&
MI->getOperand(3).isReg() && MI->getOperand(3).getReg() == 0 &&
- CanRematLoadWithDispOperand(MI->getOperand(4), TM)) {
+ MI->isInvariantLoad(AA)) {
unsigned BaseReg = MI->getOperand(1).getReg();
if (BaseReg == 0 || BaseReg == X86::RIP)
return true;
diff --git a/lib/Target/X86/X86InstrInfo.h b/lib/Target/X86/X86InstrInfo.h
index 83162fb..2237c8b 100644
--- a/lib/Target/X86/X86InstrInfo.h
+++ b/lib/Target/X86/X86InstrInfo.h
@@ -451,7 +451,8 @@
unsigned isLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) const;
unsigned isStoreToStackSlot(const MachineInstr *MI, int &FrameIndex) const;
- bool isReallyTriviallyReMaterializable(const MachineInstr *MI) const;
+ bool isReallyTriviallyReMaterializable(const MachineInstr *MI,
+ AliasAnalysis *AA) const;
void reMaterialize(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI,
unsigned DestReg, unsigned SubIdx,
const MachineInstr *Orig) const;