- Change MachineInstr::isIdenticalTo to take a new option that determines whether it should skip checking defs or at least virtual register defs. This subsumes part of the TargetInstrInfo::isIdentical functionality.

- Eliminate TargetInstrInfo::isIdentical and replace it with produceSameValue. In the default case, produceSameValue just checks whether two machine instructions are identical (except for virtual register defs). But targets may override it to check for unusual cases (e.g. ARM pic loads from constant pools).

llvm-svn: 97628

1 files changed, 5 insertions, 31 deletions

diff --git a/llvm/lib/CodeGen/TargetInstrInfoImpl.cpp b/llvm/lib/CodeGen/TargetInstrInfoImpl.cpp
index a0fccabdb5a..e9e998f81d5 100644
--- a/llvm/lib/CodeGen/TargetInstrInfoImpl.cpp
+++ b/llvm/lib/CodeGen/TargetInstrInfoImpl.cpp
@@ -150,6 +150,11 @@ void TargetInstrInfoImpl::reMaterialize(MachineBasicBlock &MBB,
   MBB.insert(I, MI);
 }
 
+bool TargetInstrInfoImpl::produceSameValue(const MachineInstr *MI0,
+                                           const MachineInstr *MI1) const {
+  return MI0->isIdenticalTo(MI1, MachineInstr::IgnoreVRegDefs);
+}
+
 MachineInstr *TargetInstrInfoImpl::duplicate(MachineInstr *Orig,
                                              MachineFunction &MF) const {
   assert(!Orig->getDesc().isNotDuplicable() &&
@@ -157,37 +162,6 @@ MachineInstr *TargetInstrInfoImpl::duplicate(MachineInstr *Orig,
   return MF.CloneMachineInstr(Orig);
 }
 
-bool
-TargetInstrInfoImpl::isIdentical(const MachineInstr *MI,
-                                 const MachineInstr *Other,
-                                 const MachineRegisterInfo *MRI) const {
-  if (MI->getOpcode() != Other->getOpcode() ||
-      MI->getNumOperands() != Other->getNumOperands())
-    return false;
-
-  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
-    const MachineOperand &MO = MI->getOperand(i);
-    const MachineOperand &OMO = Other->getOperand(i);
-    if (MO.isReg() && MO.isDef()) {
-      assert(OMO.isReg() && OMO.isDef());
-      unsigned Reg = MO.getReg();
-      if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
-        if (Reg != OMO.getReg())
-          return false;
-      } else if (MRI->getRegClass(MO.getReg()) !=
-                 MRI->getRegClass(OMO.getReg()))
-        return false;
-
-      continue;
-    }
-
-    if (!MO.isIdenticalTo(OMO))
-      return false;
-  }
-
-  return true;
-}
-
 unsigned
 TargetInstrInfoImpl::GetFunctionSizeInBytes(const MachineFunction &MF) const {
   unsigned FnSize = 0;