[PATCH] D131358: [X86] (sext Cond) | C -> (zext (not Cond)) * (C + 1) - 1 if we can get a LEA out of it.

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


================
Comment at: llvm/lib/Target/X86/X86ISelLowering.cpp:48437
 
+  // (sext Cond) | C -> (zext (not Cond)) * (C + 1) - 1 if we can get a LEA out of it.
+  if (N0.getOpcode() == ISD::SUB && N0.hasOneUse() &&
----------------
Can you improve this comment? The codegen doesn't seem to pattern matching below.


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Comment at: llvm/lib/Target/X86/X86ISelLowering.cpp:48445
+    if (Cond.getOpcode() == X86ISD::SETCC && Cond.hasOneUse()) {
+      if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(N1)) {
+        unsigned Val = CN->getZExtValue();
----------------
auto *CN = 


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  https://reviews.llvm.org/D131358/new/

https://reviews.llvm.org/D131358