vendor/llvm/llvm-trunk-r306325

1 files changed, 23 insertions, 4 deletions

diff --git a/lib/Transforms/InstCombine/InstCombineInternal.h b/lib/Transforms/InstCombine/InstCombineInternal.h
index 1a7db146df42..1b0fe84dd4dd 100644
--- a/lib/Transforms/InstCombine/InstCombineInternal.h
+++ b/lib/Transforms/InstCombine/InstCombineInternal.h
@@ -95,6 +95,18 @@ static inline bool isCanonicalPredicate(CmpInst::Predicate Pred) {
   }
 }
 
+/// Return the source operand of a potentially bitcasted value while optionally
+/// checking if it has one use. If there is no bitcast or the one use check is
+/// not met, return the input value itself.
+static inline Value *peekThroughBitcast(Value *V, bool OneUseOnly = false) {
+  if (auto *BitCast = dyn_cast<BitCastInst>(V))
+    if (!OneUseOnly || BitCast->hasOneUse())
+      return BitCast->getOperand(0);
+
+  // V is not a bitcast or V has more than one use and OneUseOnly is true.
+  return V;
+}
+
 /// \brief Add one to a Constant
 static inline Constant *AddOne(Constant *C) {
   return ConstantExpr::getAdd(C, ConstantInt::get(C->getType(), 1));
@@ -276,10 +288,6 @@ public:
   Instruction *visitFDiv(BinaryOperator &I);
   Value *simplifyRangeCheck(ICmpInst *Cmp0, ICmpInst *Cmp1, bool Inverted);
   Instruction *visitAnd(BinaryOperator &I);
-  Instruction *FoldOrWithConstants(BinaryOperator &I, Value *Op, Value *A,
-                                   Value *B, Value *C);
-  Instruction *FoldXorWithConstants(BinaryOperator &I, Value *Op, Value *A,
-                                    Value *B, Value *C);
   Instruction *visitOr(BinaryOperator &I);
   Instruction *visitXor(BinaryOperator &I);
   Instruction *visitShl(BinaryOperator &I);
@@ -595,6 +603,15 @@ private:
                           Instruction::BinaryOps, Value *, Value *, Value *,
                           Value *);
 
+  /// Match a select chain which produces one of three values based on whether
+  /// the LHS is less than, equal to, or greater than RHS respectively.
+  /// Return true if we matched a three way compare idiom. The LHS, RHS, Less,
+  /// Equal and Greater values are saved in the matching process and returned to
+  /// the caller.
+  bool matchThreeWayIntCompare(SelectInst *SI, Value *&LHS, Value *&RHS,
+                               ConstantInt *&Less, ConstantInt *&Equal,
+                               ConstantInt *&Greater);
+
   /// \brief Attempts to replace V with a simpler value based on the demanded
   /// bits.
   Value *SimplifyDemandedUseBits(Value *V, APInt DemandedMask, KnownBits &Known,
@@ -672,6 +689,8 @@ private:
   Instruction *foldICmpBinOp(ICmpInst &Cmp);
   Instruction *foldICmpEquality(ICmpInst &Cmp);
 
+  Instruction *foldICmpSelectConstant(ICmpInst &Cmp, Instruction *Select,
+                                      ConstantInt *C);
   Instruction *foldICmpTruncConstant(ICmpInst &Cmp, Instruction *Trunc,
                                      const APInt *C);
   Instruction *foldICmpAndConstant(ICmpInst &Cmp, BinaryOperator *And,