llvm-project

Commit Graph

Author	SHA1	Message	Date
Tim Northover	1021d89398	AArch64: properly calculate cmpxchg status in FastISel. We were relying on the misleadingly-names $status result to actually be the status. Actually it's just a scratch register that may or may not be valid (and is the inverse of the real ststus anyway). Success can be determined by comparing the value loaded against the one we wanted to see for "cmpxchg strong" loops like this. Should fix PR28819. llvm-svn: 277513	2016-08-02 20:22:36 +00:00
Ahmed Bougacha	a0cdd79070	[AArch64][FastISel] Select -O0 legal cmpxchg. At -O0, cmpxchg survives AtomicExpand: it's mostly straightforward to select it in fast-isel, and let the pseudo be expanded later. extractvalues on the result are the tricky part: the generic logic only works for legal types (and it would be painful to make it support illegal types), so we can only support i32/i64 cmpxchg. llvm-svn: 276183	2016-07-20 21:12:32 +00:00

Author

SHA1

Message

Date

Tim Northover

1021d89398

AArch64: properly calculate cmpxchg status in FastISel.

We were relying on the misleadingly-names $status result to actually be the
status. Actually it's just a scratch register that may or may not be valid (and
is the inverse of the real ststus anyway). Success can be determined by
comparing the value loaded against the one we wanted to see for "cmpxchg
strong" loops like this.

Should fix PR28819.

llvm-svn: 277513

2016-08-02 20:22:36 +00:00

Ahmed Bougacha

a0cdd79070

[AArch64][FastISel] Select -O0 legal cmpxchg.

At -O0, cmpxchg survives AtomicExpand: it's mostly straightforward
to select it in fast-isel, and let the pseudo be expanded later.

extractvalues on the result are the tricky part: the generic logic
only works for legal types (and it would be painful to make it
support illegal types), so we can only support i32/i64 cmpxchg.

llvm-svn: 276183

2016-07-20 21:12:32 +00:00

2 Commits