[llvm] f7245ef - [DAGCombiner] ISD::SHL/SRA/SRL - use general SelectionDAG::FoldConstantArithmetic

[Simon Pilgrim via llvm-commits]

Author: Simon Pilgrim
Date: 2020-01-29T18:49:42Z
New Revision: f7245ef8976d9dc85aab0bd86770ef46947629a0

URL: https://github.com/llvm/llvm-project/commit/f7245ef8976d9dc85aab0bd86770ef46947629a0
DIFF: https://github.com/llvm/llvm-project/commit/f7245ef8976d9dc85aab0bd86770ef46947629a0.diff

LOG: [DAGCombiner] ISD::SHL/SRA/SRL - use general SelectionDAG::FoldConstantArithmetic

This handles all the constant splat / opaque testing for us.

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 8945633e186e..fe201a6f94e3 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -7494,10 +7494,8 @@ SDValue DAGCombiner::visitSHL(SDNode *N) {
   ConstantSDNode *N1C = isConstOrConstSplat(N1);
 
   // fold (shl c1, c2) -> c1<<c2
-  // TODO - support non-uniform vector shift amounts.
-  ConstantSDNode *N0C = getAsNonOpaqueConstant(N0);
-  if (N0C && N1C && !N1C->isOpaque())
-    return DAG.FoldConstantArithmetic(ISD::SHL, SDLoc(N), VT, N0C, N1C);
+  if (SDValue C = DAG.FoldConstantArithmetic(ISD::SHL, SDLoc(N), VT, {N0, N1}))
+    return C;
 
   if (SDValue NewSel = foldBinOpIntoSelect(N))
     return NewSel;
@@ -7729,10 +7727,8 @@ SDValue DAGCombiner::visitSRA(SDNode *N) {
   ConstantSDNode *N1C = isConstOrConstSplat(N1);
 
   // fold (sra c1, c2) -> (sra c1, c2)
-  // TODO - support non-uniform vector shift amounts.
-  ConstantSDNode *N0C = getAsNonOpaqueConstant(N0);
-  if (N0C && N1C && !N1C->isOpaque())
-    return DAG.FoldConstantArithmetic(ISD::SRA, SDLoc(N), VT, N0C, N1C);
+  if (SDValue C = DAG.FoldConstantArithmetic(ISD::SRA, SDLoc(N), VT, {N0, N1}))
+    return C;
 
   if (SDValue NewSel = foldBinOpIntoSelect(N))
     return NewSel;
@@ -7915,10 +7911,8 @@ SDValue DAGCombiner::visitSRL(SDNode *N) {
   ConstantSDNode *N1C = isConstOrConstSplat(N1);
 
   // fold (srl c1, c2) -> c1 >>u c2
-  // TODO - support non-uniform vector shift amounts.
-  ConstantSDNode *N0C = getAsNonOpaqueConstant(N0);
-  if (N0C && N1C && !N1C->isOpaque())
-    return DAG.FoldConstantArithmetic(ISD::SRL, SDLoc(N), VT, N0C, N1C);
+  if (SDValue C = DAG.FoldConstantArithmetic(ISD::SRL, SDLoc(N), VT, {N0, N1}))
+    return C;
 
   if (SDValue NewSel = foldBinOpIntoSelect(N))
     return NewSel;