[llvm] 1139664 - [DAG] Cleanup DAGCombiner::CombineConsecutiveLoads early-outs. NFCI.

[Simon Pilgrim via llvm-commits]

Author: Simon Pilgrim
Date: 2021-08-03T13:47:55+01:00
New Revision: 11396641e46c22fe8fede7c2b49d6f055641a220

URL: https://github.com/llvm/llvm-project/commit/11396641e46c22fe8fede7c2b49d6f055641a220
DIFF: https://github.com/llvm/llvm-project/commit/11396641e46c22fe8fede7c2b49d6f055641a220.diff

LOG: [DAG] Cleanup DAGCombiner::CombineConsecutiveLoads early-outs. NFCI.

We had some similar hasOneUse/isNON_EXTLoad early-outs spread out over different parts of the method - we should pull them all together.

Noticed while triaging PR45116

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 1bba7232eb14..2b1a1b2d9d0e 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -12536,8 +12536,8 @@ static SDNode *getBuildPairElt(SDNode *N, unsigned i) {
 SDValue DAGCombiner::CombineConsecutiveLoads(SDNode *N, EVT VT) {
   assert(N->getOpcode() == ISD::BUILD_PAIR);
 
-  LoadSDNode *LD1 = dyn_cast<LoadSDNode>(getBuildPairElt(N, 0));
-  LoadSDNode *LD2 = dyn_cast<LoadSDNode>(getBuildPairElt(N, 1));
+  auto *LD1 = dyn_cast<LoadSDNode>(getBuildPairElt(N, 0));
+  auto *LD2 = dyn_cast<LoadSDNode>(getBuildPairElt(N, 1));
 
   // A BUILD_PAIR is always having the least significant part in elt 0 and the
   // most significant part in elt 1. So when combining into one large load, we
@@ -12545,13 +12545,14 @@ SDValue DAGCombiner::CombineConsecutiveLoads(SDNode *N, EVT VT) {
   if (DAG.getDataLayout().isBigEndian())
     std::swap(LD1, LD2);
 
-  if (!LD1 || !LD2 || !ISD::isNON_EXTLoad(LD1) || !LD1->hasOneUse() ||
+  if (!LD1 || !LD2 || !ISD::isNON_EXTLoad(LD1) || !ISD::isNON_EXTLoad(LD2) ||
+      !LD1->hasOneUse() || !LD2->hasOneUse() ||
       LD1->getAddressSpace() != LD2->getAddressSpace())
     return SDValue();
+
   EVT LD1VT = LD1->getValueType(0);
   unsigned LD1Bytes = LD1VT.getStoreSize();
-  if (ISD::isNON_EXTLoad(LD2) && LD2->hasOneUse() &&
-      DAG.areNonVolatileConsecutiveLoads(LD2, LD1, LD1Bytes, 1)) {
+  if (DAG.areNonVolatileConsecutiveLoads(LD2, LD1, LD1Bytes, 1)) {
     Align Alignment = LD1->getAlign();
     Align NewAlign = DAG.getDataLayout().getABITypeAlign(
         VT.getTypeForEVT(*DAG.getContext()));