[llvm] c72992b - [DAG] visitABS - use FoldConstantArithmetic to attempt to constant fold

[Simon Pilgrim via llvm-commits]

Author: Simon Pilgrim
Date: 2024-10-18T10:10:43+01:00
New Revision: c72992bf897b22465b2c80343b1b4a5afd1508ef

URL: https://github.com/llvm/llvm-project/commit/c72992bf897b22465b2c80343b1b4a5afd1508ef
DIFF: https://github.com/llvm/llvm-project/commit/c72992bf897b22465b2c80343b1b4a5afd1508ef.diff

LOG: [DAG] visitABS - use FoldConstantArithmetic to attempt to constant fold

Don't rely on isConstantFPBuildVectorOrConstantFP followed by getNode() will constant fold - FoldConstantArithmetic will do all of this for us.

Cleanup for #112682

Added: 
    

Modified: 
    llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

Removed: 
    


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diff  --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 18439b87a83b7d..2f829be97b0713 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -18433,10 +18433,11 @@ SDValue DAGCombiner::visitFMinMax(SDNode *N) {
 SDValue DAGCombiner::visitFABS(SDNode *N) {
   SDValue N0 = N->getOperand(0);
   EVT VT = N->getValueType(0);
+  SDLoc DL(N);
 
   // fold (fabs c1) -> fabs(c1)
-  if (DAG.isConstantFPBuildVectorOrConstantFP(N0))
-    return DAG.getNode(ISD::FABS, SDLoc(N), VT, N0);
+  if (SDValue C = DAG.FoldConstantArithmetic(ISD::FABS, DL, VT, {N0}))
+    return C;
 
   // fold (fabs (fabs x)) -> (fabs x)
   if (N0.getOpcode() == ISD::FABS)
@@ -18445,7 +18446,7 @@ SDValue DAGCombiner::visitFABS(SDNode *N) {
   // fold (fabs (fneg x)) -> (fabs x)
   // fold (fabs (fcopysign x, y)) -> (fabs x)
   if (N0.getOpcode() == ISD::FNEG || N0.getOpcode() == ISD::FCOPYSIGN)
-    return DAG.getNode(ISD::FABS, SDLoc(N), VT, N0.getOperand(0));
+    return DAG.getNode(ISD::FABS, DL, VT, N0.getOperand(0));
 
   if (SDValue Cast = foldSignChangeInBitcast(N))
     return Cast;