Revamp the ValueMapper interfaces in a couple ways:

1. Take a flags argument instead of a bool.  This makes
   it more clear to the reader what it is used for.
2. Add a flag that says that "remapping a value not in the
   map is ok".
3. Reimplement MapValue to share a bunch of code and be a lot
   more efficient.  For lookup failures, don't drop null values
   into the map.
4. Using the new flag a bunch of code can vaporize in LinkModules
   and LoopUnswitch, kill it.

No functionality change.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123058 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 1 insertions, 14 deletions

diff --git a/lib/Transforms/Scalar/LoopUnswitch.cpp b/lib/Transforms/Scalar/LoopUnswitch.cpp
index 20d7019c21..0fc416d674 100644
--- a/lib/Transforms/Scalar/LoopUnswitch.cpp
+++ b/lib/Transforms/Scalar/LoopUnswitch.cpp
@@ -457,19 +457,6 @@ bool LoopUnswitch::UnswitchIfProfitable(Value *LoopCond, Constant *Val) {
   return true;
 }
 
-// RemapInstruction - Convert the instruction operands from referencing the
-// current values into those specified by VMap.
-//
-static inline void RemapInstruction(Instruction *I,
-                                    ValueToValueMapTy &VMap) {
-  for (unsigned op = 0, E = I->getNumOperands(); op != E; ++op) {
-    Value *Op = I->getOperand(op);
-    ValueToValueMapTy::iterator It = VMap.find(Op);
-    if (It != VMap.end()) Op = It->second;
-    I->setOperand(op, Op);
-  }
-}
-
 /// CloneLoop - Recursively clone the specified loop and all of its children,
 /// mapping the blocks with the specified map.
 static Loop *CloneLoop(Loop *L, Loop *PL, ValueToValueMapTy &VM,
@@ -664,7 +651,7 @@ void LoopUnswitch::UnswitchNontrivialCondition(Value *LIC, Constant *Val,
   for (unsigned i = 0, e = NewBlocks.size(); i != e; ++i)
     for (BasicBlock::iterator I = NewBlocks[i]->begin(),
            E = NewBlocks[i]->end(); I != E; ++I)
-      RemapInstruction(I, VMap);
+      RemapInstruction(I, VMap,RF_NoModuleLevelChanges|RF_IgnoreMissingEntries);
   
   // Rewrite the original preheader to select between versions of the loop.
   BranchInst *OldBR = cast<BranchInst>(loopPreheader->getTerminator());