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| author | Jan Beulich <jbeulich@novell.com> | 2019-06-25 09:40:44 +0200 |
|---|---|---|
| committer | Jan Beulich <jbeulich@suse.com> | 2019-06-25 09:40:44 +0200 |
| commit | 4970191fa557c4769697fb41db06f2dcb5f7de2e (patch) | |
| tree | 01bb03968b1e653e8ef506878ddf48ca06982400 /gas | |
| parent | 54fbadc0c35f3dad663e2e175ea8d60546ffd710 (diff) | |
| download | gdb-4970191fa557c4769697fb41db06f2dcb5f7de2e.zip gdb-4970191fa557c4769697fb41db06f2dcb5f7de2e.tar.gz gdb-4970191fa557c4769697fb41db06f2dcb5f7de2e.tar.bz2 | |
x86: document certain command line options as "dangerous"
Errata BT36, BT41, and BT230 mean that gas may, when using one ofthese
options, produce code that causes #UD on (at least) SandyBridge systems.
Diffstat (limited to 'gas')
| -rw-r--r-- | gas/ChangeLog | 5 | ||||
| -rw-r--r-- | gas/doc/c-i386.texi | 6 |
2 files changed, 11 insertions, 0 deletions
diff --git a/gas/ChangeLog b/gas/ChangeLog index d2175b6..b76ae78 100644 --- a/gas/ChangeLog +++ b/gas/ChangeLog @@ -1,5 +1,10 @@ 2019-06-25 Jan Beulich <jbeulich@suse.com> + * doc/c-i386.texi: Mark -mavxscalar= and -mvexwig as dangrous to + use. + +2019-06-25 Jan Beulich <jbeulich@suse.com> + * tc-i386.c (process_suffix): Use is_any_vex_encoding(). 2019-06-25 Jan Beulich <jbeulich@suse.com> diff --git a/gas/doc/c-i386.texi b/gas/doc/c-i386.texi index 9d821ae..908c6ca 100644 --- a/gas/doc/c-i386.texi +++ b/gas/doc/c-i386.texi @@ -303,6 +303,9 @@ AVX instructions with 128bit vector length, which is the default. @option{-mavxscalar=@var{256}} will encode scalar AVX instructions with 256bit vector length. +WARNING: Don't use this for production code - due to CPU errata the +resulting code may not work on certain models. + @cindex @samp{-mvexwig=} option, i386 @cindex @samp{-mvexwig=} option, x86-64 @item -mvexwig=@var{0} @@ -313,6 +316,9 @@ instructions with vex.w = 0, which is the default. @option{-mvexwig=@var{1}} will encode WIG EVEX instructions with vex.w = 1. +WARNING: Don't use this for production code - due to CPU errata the +resulting code may not work on certain models. + @cindex @samp{-mevexlig=} option, i386 @cindex @samp{-mevexlig=} option, x86-64 @item -mevexlig=@var{128} |