- Add LiveVariables::replaceKillInstruction. This does a subset of instructionChanged. That is, it only update the VarInfo.kills if the new instruction is known to have the correct dead and kill markers.
- CommuteInstruction copies kill / dead markers over to new instruction. So use replaceKillInstruction instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53061 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/CodeGen/LiveVariables.h b/include/llvm/CodeGen/LiveVariables.h
index efa5f3c..bbefbe0 100644
--- a/include/llvm/CodeGen/LiveVariables.h
+++ b/include/llvm/CodeGen/LiveVariables.h
@@ -189,6 +189,11 @@
/// the records for NewMI.
void instructionChanged(MachineInstr *OldMI, MachineInstr *NewMI);
+ /// replaceKillInstruction - Update register kill info by replacing a kill
+ /// instruction with a new one.
+ void replaceKillInstruction(unsigned Reg, MachineInstr *OldMI,
+ MachineInstr *NewMI);
+
/// addVirtualRegisterKilled - Add information about the fact that the
/// specified register is killed after being used by the specified
/// instruction. If AddIfNotFound is true, add a implicit operand if it's
diff --git a/lib/CodeGen/LiveVariables.cpp b/lib/CodeGen/LiveVariables.cpp
index ab73c97..ee4492b 100644
--- a/lib/CodeGen/LiveVariables.cpp
+++ b/lib/CodeGen/LiveVariables.cpp
@@ -684,6 +684,15 @@
}
}
+/// replaceKillInstruction - Update register kill info by replacing a kill
+/// instruction with a new one.
+void LiveVariables::replaceKillInstruction(unsigned Reg, MachineInstr *OldMI,
+ MachineInstr *NewMI) {
+ VarInfo &VI = getVarInfo(Reg);
+ if (VI.removeKill(OldMI))
+ VI.Kills.push_back(NewMI); // Yes, there was a kill of it
+}
+
/// removeVirtualRegistersKilled - Remove all killed info for the specified
/// instruction.
void LiveVariables::removeVirtualRegistersKilled(MachineInstr *MI) {
diff --git a/lib/CodeGen/TwoAddressInstructionPass.cpp b/lib/CodeGen/TwoAddressInstructionPass.cpp
index d2e5288..480d6dd 100644
--- a/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -375,10 +375,9 @@
DOUT << "2addr: COMMUTED TO: " << *NewMI;
// If the instruction changed to commute it, update livevar.
if (NewMI != mi) {
- if (LV) {
+ if (LV)
// Update live variables
- LV->instructionChanged(mi, NewMI);
- }
+ LV->replaceKillInstruction(regC, mi, NewMI);
mbbi->insert(mi, NewMI); // Insert the new inst
mbbi->erase(mi); // Nuke the old inst.