[PATCH] D60096: [InstCombine] Simplify ctlz/cttz with bitreverse

[Sanjay Patel via Phabricator via llvm-commits]

spatel accepted this revision.
spatel added a comment.
This revision is now accepted and ready to land.

LGTM - thanks!



================
Comment at: lib/Transforms/InstCombine/InstCombineCalls.cpp:1333-1336
+    return IC.replaceInstUsesWith(
+        II,
+        IC.Builder.CreateBinaryIntrinsic(
+            IsTZ ? Intrinsic::ctlz : Intrinsic::cttz, X, II.getArgOperand(1)));
----------------
Might be less hassle to not to use the builder directly:

```
        Intrinsic::ID ID = IsTZ ? Intrinsic::ctlz : Intrinsic::cttz;
        Function *F = Intrinsic::getDeclaration(II.getModule(), ID, II.getType());
        return CallInst::Create(F, { X, II.getArgOperand(1) });

```


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D60096/new/

https://reviews.llvm.org/D60096