[PATCH] [X86] Don't transform atomic-load-add into an inc/dec when inc/dec is slow

[JF Bastien]

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Comment at: lib/Target/X86/X86ISelDAGToDAG.cpp:1711
@@ -1710,1 +1710,3 @@
+getAtomicLoadArithTargetConstant(SelectionDAG *CurDAG, SDLoc dl,
+                                 enum AtomicOpc &Op, MVT NVT, SDValue Val) {
   if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Val)) {
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Can you keep this `static` and pass in the `Subtarget`?

http://reviews.llvm.org/D5678