[PATCH] D135633: [GlobalISel] Combine things like (z = x <= 0 ? z = x : z = 0) -> x & (x >> bw-1)

[Amara Emerson via Phabricator via llvm-commits]

aemerson added inline comments.


================
Comment at: llvm/include/llvm/CodeGen/TargetLowering.h:724-731
+  virtual bool hasAndNotCompare(LLT Ty) const { return false; }
+
+  /// LLT variant
+  virtual bool hasAndNot(LLT Ty) const {
+    // If the target has the more complex version of this operation, assume that
+    // it has this operation too.
+    return hasAndNotCompare(Ty);
----------------
arsenm wrote:
> Wouldn't the target just not add this combine if it didn't want it?
@paquette Echoing Matt's question: is this hook actually needed?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D135633/new/

https://reviews.llvm.org/D135633