[InstCombine] reduce code duplication; NFC

eidola7 · Aug 16, 2020 · 3fed67b · 3fed67b
1 parent 4d5fdff
commit 3fed67b
Showing 1 changed file with 11 additions and 13 deletions.
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -1199,29 +1199,27 @@ Instruction *InstCombinerImpl::visitCallInst(CallInst &CI) {
     break;
   }
   case Intrinsic::copysign: {
-    if (SignBitMustBeZero(II->getArgOperand(1), &TLI)) {
+    Value *Mag = II->getArgOperand(0), *Sign = II->getArgOperand(1);
+    if (SignBitMustBeZero(Sign, &TLI)) {
       // If we know that the sign argument is positive, reduce to FABS:
-      // copysign X, Pos --> fabs X
-      Value *Fabs = Builder.CreateUnaryIntrinsic(Intrinsic::fabs,
-                                                 II->getArgOperand(0), II);
+      // copysign Mag, +Sign --> fabs Mag
+      Value *Fabs = Builder.CreateUnaryIntrinsic(Intrinsic::fabs, Mag, II);
       return replaceInstUsesWith(*II, Fabs);
     }
     // TODO: There should be a ValueTracking sibling like SignBitMustBeOne.
     const APFloat *C;
-    if (match(II->getArgOperand(1), m_APFloat(C)) && C->isNegative()) {
+    if (match(Sign, m_APFloat(C)) && C->isNegative()) {
       // If we know that the sign argument is negative, reduce to FNABS:
-      // copysign X, Neg --> fneg (fabs X)
-      Value *Fabs = Builder.CreateUnaryIntrinsic(Intrinsic::fabs,
-                                                 II->getArgOperand(0), II);
+      // copysign Mag, -Sign --> fneg (fabs Mag)
+      Value *Fabs = Builder.CreateUnaryIntrinsic(Intrinsic::fabs, Mag, II);
       return replaceInstUsesWith(*II, Builder.CreateFNegFMF(Fabs, II));
     }
 
     // Propagate sign argument through nested calls:
-    // copysign X, (copysign ?, SignArg) --> copysign X, SignArg
-    Value *SignArg;
-    if (match(II->getArgOperand(1),
-              m_Intrinsic<Intrinsic::copysign>(m_Value(), m_Value(SignArg))))
-      return replaceOperand(*II, 1, SignArg);
+    // copysign Mag, (copysign ?, X) --> copysign Mag, X
+    Value *X;
+    if (match(Sign, m_Intrinsic<Intrinsic::copysign>(m_Value(), m_Value(X))))
+      return replaceOperand(*II, 1, X);
 
     break;
   }