https://bugs.llvm.org/show_bug.cgi?id=50015
Bug ID: 50015
Summary: SLP vectorizer produces incorrect x86_64 code
Product: libraries
Version: trunk
Hardware: PC
OS: Windows NT
Status: NEW
Severity: enhancement
Priority: P
Component: Backend: X86
Assignee: [email protected]
Reporter: [email protected]
CC: [email protected], [email protected],
[email protected], [email protected],
[email protected]
Created attachment 24765
--> https://bugs.llvm.org/attachment.cgi?id=24765&action=edit
test.c
Clang v12 produces incorrect x86_64 code for attached program when slp
vectorizer is enabled (by default) with "-O2".
If you compile with Clang v12 using "-O1" the produced code is correct.
Compiling with Clang v12 using "-O2 -fno-slp-vectorize" also produces correct
code.
Using Clang v11 with "-O2" also produces correct code.
I bisected llvm repo to this commit:
https://github.com/llvm/llvm-project/commit/fcad8d3635cff61a2749dcef94c0d51fa1e3e413
Previous commit produces correct result for attached program.
You can also see difference in assembly & output in following godbolt:
https://godbolt.org/z/ajehqcTYc
--
You are receiving this mail because:
You are on the CC list for the bug._______________________________________________
llvm-bugs mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-bugs
