[LoopUnroll] Remove remapInstruction().

Summary:
LoopUnroll can reuse the RemapInstruction() in ValueMapper, or
remapInstructionsInBlocks() in CloneFunction, depending on the needs.
There is no need to have its own version in LoopUnroll.

By calling RemapInstruction() without TypeMapper or Materializer and
with Flags (RF_NoModuleLevelChanges | RF_IgnoreMissingLocals), it does
the same as remapInstruction(). remapInstructionsInBlocks() calls
RemapInstruction() exactly as described.

Looking at the history, I cannot find any obvious reason to have its own
version.
Reviewer: dmgreen, jdoerfert, Meinersbur, kbarton, bmahjour, etiotto,
foad, aprantl
Reviewed By: jdoerfert
Subscribers: hiraditya, zzheng, llvm-commits, prithayan, anhtuyen
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D73277

1 files changed, 2 insertions, 35 deletions

diff --git a/llvm/lib/Transforms/Utils/LoopUnroll.cpp b/llvm/lib/Transforms/Utils/LoopUnroll.cpp
index bb0b6ed..d835cb6 100644
--- a/llvm/lib/Transforms/Utils/LoopUnroll.cpp
+++ b/llvm/lib/Transforms/Utils/LoopUnroll.cpp
@@ -63,39 +63,6 @@ UnrollVerifyDomtree("unroll-verify-domtree", cl::Hidden,
 #endif
                     );
 
-/// Convert the instruction operands from referencing the current values into
-/// those specified by VMap.
-void llvm::remapInstruction(Instruction *I, ValueToValueMapTy &VMap) {
-  for (unsigned op = 0, E = I->getNumOperands(); op != E; ++op) {
-    Value *Op = I->getOperand(op);
-
-    // Unwrap arguments of dbg.value intrinsics.
-    bool Wrapped = false;
-    if (auto *V = dyn_cast<MetadataAsValue>(Op))
-      if (auto *Unwrapped = dyn_cast<ValueAsMetadata>(V->getMetadata())) {
-        Op = Unwrapped->getValue();
-        Wrapped = true;
-      }
-
-    auto wrap = [&](Value *V) {
-      auto &C = I->getContext();
-      return Wrapped ? MetadataAsValue::get(C, ValueAsMetadata::get(V)) : V;
-    };
-
-    ValueToValueMapTy::iterator It = VMap.find(Op);
-    if (It != VMap.end())
-      I->setOperand(op, wrap(It->second));
-  }
-
-  if (PHINode *PN = dyn_cast<PHINode>(I)) {
-    for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
-      ValueToValueMapTy::iterator It = VMap.find(PN->getIncomingBlock(i));
-      if (It != VMap.end())
-        PN->setIncomingBlock(i, cast<BasicBlock>(It->second));
-    }
-  }
-}
-
 /// Check if unrolling created a situation where we need to insert phi nodes to
 /// preserve LCSSA form.
 /// \param Blocks is a vector of basic blocks representing unrolled loop.
@@ -601,7 +568,7 @@ LoopUnrollResult llvm::UnrollLoop(Loop *L, UnrollLoopOptions ULO, LoopInfo *LI,
           }
 
   for (unsigned It = 1; It != ULO.Count; ++It) {
-    std::vector<BasicBlock*> NewBlocks;
+    SmallVector<BasicBlock *, 8> NewBlocks;
     SmallDenseMap<const Loop *, Loop *, 4> NewLoops;
     NewLoops[L] = L;
 
@@ -683,9 +650,9 @@ LoopUnrollResult llvm::UnrollLoop(Loop *L, UnrollLoopOptions ULO, LoopInfo *LI,
     }
 
     // Remap all instructions in the most recent iteration
+    remapInstructionsInBlocks(NewBlocks, LastValueMap);
     for (BasicBlock *NewBlock : NewBlocks) {
       for (Instruction &I : *NewBlock) {
-        ::remapInstruction(&I, LastValueMap);
         if (auto *II = dyn_cast<IntrinsicInst>(&I))
           if (II->getIntrinsicID() == Intrinsic::assume)
             AC->registerAssumption(II);