llvm-project/compiler-rt
Kostya Kortchinsky cb7912cc0f [sanitizer] Correct 64-bit atomic_store on 32-bit "other" platforms
Summary:
I think there might be something to optimize in `atomic_store`.
Currently, if everything goes well (and we have a different new value), we
always iterate 3 times.
For example, `with a = 0`, `oldval = a`, `newval = 42`, we get:
```
oldval = 0, newval = 42, curval = 0  
oldval = 0, newval = 42, curval = 42 
oldval = 42, newval = 42, curval = 42
```
and then it breaks.

Unless I am not seeing something, I don't see a point to the third iteration.
If the current value is the one we want, we should just break.
This means that 2 iterations (with a different newval) should be sufficient to
achieve what we want.

Reviewers: dvyukov, alekseyshl

Reviewed By: dvyukov

Subscribers: kubamracek, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D46597

llvm-svn: 331890
2018-05-09 16:20:52 +00:00
..
cmake Add basic compiler-rt builtins support for hexagon. 2018-05-09 14:44:54 +00:00
docs [sanitizers] Make it possible to XFAIL on the effective target, not just the default. 2016-08-09 11:50:53 +00:00
include [XRay][compiler-rt+docs] Introduce __xray_log_init_mode(...). 2018-05-04 06:01:12 +00:00
lib [sanitizer] Correct 64-bit atomic_store on 32-bit "other" platforms 2018-05-09 16:20:52 +00:00
test [libFuzzer] Guard symbolization with try-lock. 2018-05-08 23:45:05 +00:00
unittests Allow compiler-rt test targets to work with multi-config CMake generators 2017-11-13 12:57:54 +00:00
utils Remove more references to ptrace_pt_{g,s}et_sigmask 2018-03-03 18:41:38 +00:00
www
.arcconfig [compiler-rt] Set up .arcconfig to point to new Diffusion CRT repository 2017-12-06 20:55:32 +00:00
.gitignore Add .pyc files to .gitignore to compiler-rt 2017-07-24 21:51:12 +00:00
CMakeLists.txt Enable full debug info in the ASan runtime on Windows 2018-04-26 20:34:19 +00:00
CODE_OWNERS.TXT [sanitizers] remove earthdok@ from owners 2016-05-18 18:52:18 +00:00
CREDITS.TXT
LICENSE.TXT Update copyright year to 2016. 2016-03-30 22:38:50 +00:00
README.txt

README.txt

Compiler-RT
================================

This directory and its subdirectories contain source code for the compiler
support routines.

Compiler-RT is open source software. You may freely distribute it under the
terms of the license agreement found in LICENSE.txt.

================================