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Bug 51315 - [InstCombine] Failure to drop sext before bitcast-icmp
Summary: [InstCombine] Failure to drop sext before bitcast-icmp
Status: RESOLVED FIXED
Alias: None
Product: libraries
Classification: Unclassified
Component: Scalar Optimizations (show other bugs)
Version: trunk
Hardware: PC Linux
: P enhancement
Assignee: Unassigned LLVM Bugs
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2021-08-03 02:27 PDT by Roman Lebedev
Modified: 2021-08-07 05:24 PDT (History)
3 users (show)

See Also:
Fixed By Commit(s): 0369714b3168

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Description Roman Lebedev 2021-08-03 02:27:47 PDT 
https://godbolt.org/z/Mf8vMfs5r
Comment 1 Sanjay Patel 2021-08-06 14:22:07 PDT 
The improvement is clear in IR, and I don't see any real perf diff on the motivating x86 codegen from bug 51259, so we might as well go with the shorter IR:
https://reviews.llvm.org/rG0369714b3168

If there's some enhancement/generalization that would make that better, let me know. Otherwise, we can resolve this.
Comment 2 Roman Lebedev 2021-08-06 23:13:21 PDT 
(In reply to Sanjay Patel from comment #1)
> If there's some enhancement/generalization that would make that better, let
> me know. Otherwise, we can resolve this.

I think we can resolve this, yes.