[llvm-bugs] [Bug 33539] New: Codegen for TLS variables calls __tls_get_info far too many times.

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=33539

            Bug ID: 33539
           Summary: Codegen for TLS variables calls __tls_get_info far too
                    many times.
           Product: new-bugs
           Version: 4.0
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: new bugs
          Assignee: unassignedbugs at nondot.org
          Reporter: sstewartgallus00 at mylangara.bc.ca
                CC: llvm-bugs at lists.llvm.org

Code like https://godbolt.org/g/JiSXBG calls __tls_get_info a bunch of times
instead of just once.

This has to be explicitly worked around like in
https://sstewartgallus.com/git?p=weakrand.git;a=blob_plain;f=src/lib.rs;hb=HEAD
in order to only call __tls_get_info once.

This single optimization sped up one of my benchmarks from 220us to 210us in
some of my heavy concurrent code.

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20170621/7309b35a/attachment.html>