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| author | Erik de Castro Lopo <erikd@mega-nerd.com> | 2015-05-28 02:57:28 +0000 |
|---|---|---|
| committer | Erik de Castro Lopo <erikd@mega-nerd.com> | 2015-06-01 19:40:07 +1000 |
| commit | f6ca6959e54ede0b28735ab7e011c16b3cb172db (patch) | |
| tree | e91c6daabedd093a0229605e6478a589dd682e1a /includes | |
| parent | f5b43ce177e40a34afb1913bc0ec866185ed95d7 (diff) | |
| download | haskell-f6ca6959e54ede0b28735ab7e011c16b3cb172db.tar.gz | |
rts: Fix aarch64 implementation of xchg
In the previous implementation, the `stlxr` instruction clobbered
the value that was supposed to be returned by the the `xchg`
function.
Signed-off-by: Erik de Castro Lopo <erikd@mega-nerd.com>
Test Plan: build on aarch64
Reviewers: austin, bgamari, rwbarton
Subscribers: bgamari, thomie
Differential Revision: https://phabricator.haskell.org/D932
Diffstat (limited to 'includes')
| -rw-r--r-- | includes/stg/SMP.h | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/includes/stg/SMP.h b/includes/stg/SMP.h index 10ef83ee13..fbc8bdcfa3 100644 --- a/includes/stg/SMP.h +++ b/includes/stg/SMP.h @@ -158,13 +158,11 @@ xchg(StgPtr p, StgWord w) : "memory" ); #elif aarch64_HOST_ARCH - // Don't think we actually use tmp here, but leaving - // it for consistent numbering StgWord tmp; __asm__ __volatile__ ( "1: ldaxr %0, [%3]\n" - " stlxr %w0, %2, [%3]\n" - " cbnz %w0, 1b\n" + " stlxr %w1, %2, [%3]\n" + " cbnz %w1, 1b\n" " dmb sy\n" : "=&r" (result), "=&r" (tmp) : "r" (w), "r" (p) |