[Bug target/43718] New: march doesn't conform to documentation

[Bug target/43718] New: march doesn't conform to documentation

[kjslag at gmail dot com]

The -msse* options are not enabled by -march=core2. The gcc doc states:
core2
Intel Core2 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3 and SSSE3
instruction set support.

-mtune=core2 is not implied by -march=core2. The gcc doc states:
-march=cpu-type
...  Moreover, specifying -march=cpu-type implies -mtune=cpu-type.

$ gcc -march=core2  -Q --help=target -v &> gcc.core2
$ gcc -march=native -Q --help=target -v &> gcc.native
$ diff gcc.core2 gcc.native 
6,7c6,7
< COLLECT_GCC_OPTIONS='-march=core2' '-Q' '-fhelp=target' '-v'
<  /usr/lib/gcc/x86_64-unknown-linux-gnu/4.4.3/cc1 -v help-dummy -dumpbase
help-dummy -march=core2 -auxbase help-dummy -version -fhelp=target -o
/tmp/ccEak63E.s
---
> COLLECT_GCC_OPTIONS= '-Q' '-fhelp=target' '-v'
>  /usr/lib/gcc/x86_64-unknown-linux-gnu/4.4.3/cc1 -v help-dummy -march=core2 -mcx16 -msahf -msse4.1 --param l1-cache-size=32 --param l1-cache-line-size=64 --param l2-cache-size=3072 -mtune=core2 -dumpbase help-dummy -auxbase help-dummy -version -fhelp=target -o /tmp/cc5b5n0x.s                                                                            
30c30
<   -mcx16                                      [disabled]
---
>   -mcx16                                      [enabled]
52c52
<   -mno-sse4                                   [enabled]
---
>   -mno-sse4                                   [disabled]
63c63
<   -msahf                                      [disabled]
---
>   -msahf                                      [enabled]
65,66c65,66
<   -msse                                       [disabled]
<   -msse2                                      [disabled]
---
>   -msse                                       [enabled]
>   -msse2                                      [enabled]
68c68
<   -msse3                                      [disabled]
---
>   -msse3                                      [enabled]
70c70
<   -msse4.1                                    [disabled]
---
>   -msse4.1                                    [enabled]
75c75
<   -mssse3                                     [disabled]
---
>   -mssse3                                     [enabled]
81c81
<   -mtune=                     
---
>   -mtune=                                     core2
85,86c85,86
< COLLECT_GCC_OPTIONS='-march=core2' '-Q' '-fhelp=target' '-v'
<  as -V -Qy -o /tmp/ccB1vZZ0.o /tmp/ccEak63E.s
---
> COLLECT_GCC_OPTIONS= '-Q' '-fhelp=target' '-v'
>  as -V -Qy -o /tmp/ccxxWZjC.o /tmp/cc5b5n0x.s

$ uname -a
Linux J 2.6.33-ARCH #1 SMP PREEMPT Sun Apr 4 10:27:30 CEST 2010 x86_64 Intel(R)
Core(TM)2 Duo CPU T8300 @ 2.40GHz GenuineIntel GNU/Linux

Thanks


-- 
           Summary: march doesn't conform to documentation
           Product: gcc
           Version: 4.4.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: kjslag at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43718

[Bug target/43718] march doesn't conform to documentation

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2010-04-12 20:44 -------
I think this is really an issue of how --help=target is displaying the
enable/disable part.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43718

[Bug middle-end/43718] march does not display --help=target enable/disable correctly

[pinskia at gcc dot gnu dot org]

------- Comment #2 from pinskia at gcc dot gnu dot org  2010-04-12 20:48 -------
OVERRIDE_OPTIONS is called after the printing out the --help message.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |minor
          Component|target                      |middle-end
           Keywords|                            |diagnostic
            Summary|march doesn't conform to    |march does not display --
                   |documentation               |help=target enable/disable
                   |                            |correctly


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43718