[foldMemoryOperand()] Pass LiveIntervals to enable liveness check.

SystemZ (and probably other targets as well) can fold a memory operand
by changing the opcode into a new instruction that as a side-effect
also clobbers the CC-reg.

In order to do this, liveness of that reg must first be checked. When
LIS is passed, getRegUnit() can be called on it and the right
LiveRange is computed on demand.

Reviewed by Matthias Braun.
http://reviews.llvm.org/D19861

llvm-svn: 269026

1 files changed, 6 insertions, 4 deletions

diff --git a/llvm/lib/CodeGen/TargetInstrInfo.cpp b/llvm/lib/CodeGen/TargetInstrInfo.cpp
index 800ad6d1bb4..6d90f9dd819 100644
--- a/llvm/lib/CodeGen/TargetInstrInfo.cpp
+++ b/llvm/lib/CodeGen/TargetInstrInfo.cpp
@@ -497,7 +497,8 @@ static MachineInstr *foldPatchpoint(MachineFunction &MF, MachineInstr *MI,
 /// stream.
 MachineInstr *TargetInstrInfo::foldMemoryOperand(MachineBasicBlock::iterator MI,
                                                  ArrayRef<unsigned> Ops,
-                                                 int FI) const {
+                                                 int FI,
+                                                 LiveIntervals *LIS) const {
   unsigned Flags = 0;
   for (unsigned i = 0, e = Ops.size(); i != e; ++i)
     if (MI->getOperand(Ops[i]).isDef())
@@ -519,7 +520,7 @@ MachineInstr *TargetInstrInfo::foldMemoryOperand(MachineBasicBlock::iterator MI,
       MBB->insert(MI, NewMI);
   } else {
     // Ask the target to do the actual folding.
-    NewMI = foldMemoryOperandImpl(MF, MI, Ops, MI, FI);
+    NewMI = foldMemoryOperandImpl(MF, MI, Ops, MI, FI, LIS);
   }
 
   if (NewMI) {
@@ -778,7 +779,8 @@ void TargetInstrInfo::genAlternativeCodeSequence(
 /// stack slot.
 MachineInstr *TargetInstrInfo::foldMemoryOperand(MachineBasicBlock::iterator MI,
                                                  ArrayRef<unsigned> Ops,
-                                                 MachineInstr *LoadMI) const {
+                                                 MachineInstr *LoadMI,
+                                                 LiveIntervals *LIS) const {
   assert(LoadMI->canFoldAsLoad() && "LoadMI isn't foldable!");
 #ifndef NDEBUG
   for (unsigned i = 0, e = Ops.size(); i != e; ++i)
@@ -800,7 +802,7 @@ MachineInstr *TargetInstrInfo::foldMemoryOperand(MachineBasicBlock::iterator MI,
       NewMI = MBB.insert(MI, NewMI);
   } else {
     // Ask the target to do the actual folding.
-    NewMI = foldMemoryOperandImpl(MF, MI, Ops, MI, LoadMI);
+    NewMI = foldMemoryOperandImpl(MF, MI, Ops, MI, LoadMI, LIS);
   }
 
   if (!NewMI) return nullptr;