Bug 418702

Summary:	ARMv8.1 Paired register compare-and-swap instructions are not supported
Product:	[Developer tools] valgrind	Reporter:	ahashmi <assad.hashmi>
Component:	vex	Assignee:	Julian Seward <jseward>
Status:	RESOLVED FIXED
Severity:	normal
Priority:	NOR
Version First Reported In:	3.14.0
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Bug Depends on:
Bug Blocks:	414270
Attachments:	Patch implements ARM v8.1 CASP instructions Patch tests ARM v8.1 CASP instructions Patch tests ARM v8.1 CASP instructions

Description ahashmi 2020-03-10 11:22:17 UTC

SUMMARY
The following paired register compare-and-swap instructions are not currently supported:
CASP, CASPA, CASPAL, CASPL

STEPS TO REPRODUCE
Compile with -march=armv8.1-a and if the compiler generates any of the above, valgrind will exit with unknown instruction error.

ADDITIONAL INFORMATION
These are also referred to as double register compare-and-swap instructions on some architectures.

Comment 1 ahashmi 2020-03-10 14:32:20 UTC

Created attachment 126710 [details]
Patch implements ARM v8.1 CASP instructions

Comment 2 ahashmi 2020-03-10 14:33:12 UTC

Created attachment 126711 [details]
Patch tests ARM v8.1 CASP instructions

Comment 3 ahashmi 2020-03-10 15:11:55 UTC

Created attachment 126714 [details]
Patch tests ARM v8.1 CASP instructions

Comment 4 Julian Seward 2020-03-11 14:09:00 UTC

Committed:

9608e801932b8c76f0c23e40b384a08c59b368f0 implementation
1e1b7976938956ef709d7537ffaa723b76103c05 test cases

Thanks for the patches!