diff options
| author | Philip Guenther <guenther@cvs.openbsd.org> | 2018-05-26 17:28:18 +0000 |
|---|---|---|
| committer | Philip Guenther <guenther@cvs.openbsd.org> | 2018-05-26 17:28:18 +0000 |
| commit | c4d7bb8167329f310e68bccb188a4db3fa9e7381 (patch) | |
| tree | 5791d1a2cf4c153664042ad5ed30ceb9c47bab3b | |
| parent | f4eabd5ecd21c9ffbf807914fbd43e281d3f4f66 (diff) | |
Update comment to reflect xsave
| -rw-r--r-- | sys/arch/amd64/include/fpu.h | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/sys/arch/amd64/include/fpu.h b/sys/arch/amd64/include/fpu.h index ff12f60ba69..96536774abc 100644 --- a/sys/arch/amd64/include/fpu.h +++ b/sys/arch/amd64/include/fpu.h @@ -1,4 +1,4 @@ -/* $OpenBSD: fpu.h,v 1.12 2017/04/27 06:16:39 mlarkin Exp $ */ +/* $OpenBSD: fpu.h,v 1.13 2018/05/26 17:28:17 guenther Exp $ */ /* $NetBSD: fpu.h,v 1.1 2003/04/26 18:39:40 fvdl Exp $ */ #ifndef _MACHINE_FPU_H_ @@ -7,10 +7,11 @@ #include <sys/types.h> /* - * amd64 only uses the extended save/restore format used - * by fxsave/fsrestore, to always deal with the SSE registers, - * which are part of the ABI to pass floating point values. - * Must be stored in memory on a 16-byte boundary. + * If the CPU supports xsave/xrstor then we use them so that we can provide + * AVX support. Otherwise we require fxsave/fxrstor, as the SSE registers + * are part of the ABI for passing floating point values. + * While fxsave/fxrstor only required 16-byte alignment for the save area, + * xsave/xrstor requires the save area to have 64-byte alignment. */ struct fxsave64 { |