[ValueTracking] Remove duplicate call to computeKnownBits for the operands of Select.

We call it unconditionally on the operands of the select. Then decide if its a min/max and call it on the min/max operands or on the select operands again. Either of those second calls will overwrite the results of the initial call so we can just delete the first call.

llvm-svn: 300256

1 files changed, 1 insertions, 5 deletions

diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index c72a3f63d05..3f8f6457480 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -976,11 +976,7 @@ static void computeKnownBitsFromOperator(const Operator *I, APInt &KnownZero,
     break;
   }
   case Instruction::Select: {
-    computeKnownBits(I->getOperand(2), KnownZero, KnownOne, Depth + 1, Q);
-    computeKnownBits(I->getOperand(1), KnownZero2, KnownOne2, Depth + 1, Q);
-
-    const Value *LHS;
-    const Value *RHS;
+    const Value *LHS, *RHS;
     SelectPatternFlavor SPF = matchSelectPattern(I, LHS, RHS).Flavor;
     if (SelectPatternResult::isMinOrMax(SPF)) {
       computeKnownBits(RHS, KnownZero, KnownOne, Depth + 1, Q);