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Issue 23123 - -vasm wrong result for cmpxchg16b
Summary: -vasm wrong result for cmpxchg16b
Status: RESOLVED FIXED
Alias: None
Product: D
Classification: Unclassified
Component: dmd (show other issues)
Version: D2
Hardware: x86_64 All
: P1 normal
Assignee: No Owner
URL:
Keywords: pull
Depends on:
Blocks:
 
Reported: 2022-05-18 00:13 UTC by mhh
Modified: 2022-05-18 21:50 UTC (History)
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Description mhh 2022-05-18 00:13:34 UTC 
Seems to ignore the rex prefix.
Comment 1 Dlang Bot 2022-05-18 00:21:09 UTC 
@maxhaton created dlang/dmd pull request #14136 "Fix Issue 23123 - -vasm ignored REX prefix for cmpxchg" fixing this issue:

- Fix Issue 23123 - -vasm ignored REX prefix for cmpxchg
  
  This led to a mistaken bug report because obj2asm has the same issue.
  The bug makes it look like dmd is emitting the wrong CAS instruction (but it
  actually was)

https://github.com/dlang/dmd/pull/14136
Comment 2 Dlang Bot 2022-05-18 21:50:42 UTC 
dlang/dmd pull request #14136 "Fix Issue 23123 - -vasm ignored REX prefix for cmpxchg" was merged into master:

- 1785681ed0fe34bc2bc8d3102347ec051b0971c2 by mhh:
  Fix Issue 23123 - -vasm ignored REX prefix for cmpxchg
  
  This led to a mistaken bug report because obj2asm has the same issue.
  The bug makes it look like dmd is emitting the wrong CAS instruction (but it
  actually was)

https://github.com/dlang/dmd/pull/14136