[InstrInfo] Refactor foldOperandImpl to thread through InsertPt. NFC

Summary:
This was a longstanding FIXME and is a necessary precursor to cases
where foldOperandImpl may have to create more than one instruction
(e.g. to constrain a register class). This is the split out NFC changes from
D6262.

Reviewers: pete, ributzka, uweigand, mcrosier

Reviewed By: mcrosier

Subscribers: mcrosier, ted, llvm-commits

Differential Revision: http://reviews.llvm.org/D10174

llvm-svn: 239336

1 files changed, 8 insertions, 7 deletions

diff --git a/llvm/lib/CodeGen/TargetInstrInfo.cpp b/llvm/lib/CodeGen/TargetInstrInfo.cpp
index 92488defc79..c809087d3da 100644
--- a/llvm/lib/CodeGen/TargetInstrInfo.cpp
+++ b/llvm/lib/CodeGen/TargetInstrInfo.cpp
@@ -471,11 +471,13 @@ MachineInstr *TargetInstrInfo::foldMemoryOperand(MachineBasicBlock::iterator MI,
       MI->getOpcode() == TargetOpcode::PATCHPOINT) {
     // Fold stackmap/patchpoint.
     NewMI = foldPatchpoint(MF, MI, Ops, FI, *this);
+    if (NewMI)
+      MBB->insert(MI, NewMI);
   } else {
     // Ask the target to do the actual folding.
-    NewMI =foldMemoryOperandImpl(MF, MI, Ops, FI);
+    NewMI = foldMemoryOperandImpl(MF, MI, Ops, MI, FI);
   }
- 
+
   if (NewMI) {
     NewMI->setMemRefs(MI->memoperands_begin(), MI->memoperands_end());
     // Add a memory operand, foldMemoryOperandImpl doesn't do that.
@@ -493,8 +495,7 @@ MachineInstr *TargetInstrInfo::foldMemoryOperand(MachineBasicBlock::iterator MI,
                               MFI.getObjectAlignment(FI));
     NewMI->addMemOperand(MF, MMO);
 
-    // FIXME: change foldMemoryOperandImpl semantics to also insert NewMI.
-    return MBB->insert(MI, NewMI);
+    return NewMI;
   }
 
   // Straight COPY may fold as load/store.
@@ -539,15 +540,15 @@ MachineInstr *TargetInstrInfo::foldMemoryOperand(MachineBasicBlock::iterator MI,
       isLoadFromStackSlot(LoadMI, FrameIndex)) {
     // Fold stackmap/patchpoint.
     NewMI = foldPatchpoint(MF, MI, Ops, FrameIndex, *this);
+    if (NewMI)
+      NewMI = MBB.insert(MI, NewMI);
   } else {
     // Ask the target to do the actual folding.
-    NewMI = foldMemoryOperandImpl(MF, MI, Ops, LoadMI);
+    NewMI = foldMemoryOperandImpl(MF, MI, Ops, MI, LoadMI);
   }
 
   if (!NewMI) return nullptr;
 
-  NewMI = MBB.insert(MI, NewMI);
-
   // Copy the memoperands from the load to the folded instruction.
   if (MI->memoperands_empty()) {
     NewMI->setMemRefs(LoadMI->memoperands_begin(),