[PATCH] msvcrt: Improve memmove performance on i386 and x86_64 architectures.

[Piotr Caban]

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=49663
Signed-off-by: Piotr Caban <piotr(a)codeweavers.com>
---
  dlls/msvcrt/math.c   |   2 +-
  dlls/msvcrt/msvcrt.h |   2 +
  dlls/msvcrt/string.c | 264 ++++++++++++++++++++++++++++++++++++++++++-
  3 files changed, 266 insertions(+), 2 deletions(-)

[Alexandre Julliard]

Piotr Caban <piotr(a)codeweavers.com> writes:
> +#define MEMMOVE_INIT \
> +    "movl " __ASM_NAME( "sse2_supported" ) ", %eax\n\t" \
> +    "cmp $0, %eax\n\t" \

In general you can't access global variables that way, it's not
compatible with PIC. I'd suggest doing that part from C code.

-- 
Alexandre Julliard
julliard(a)winehq.org

[Piotr Caban]

On 1/26/21 5:25 PM, Alexandre Julliard wrote:
> Piotr Caban <piotr(a)codeweavers.com> writes:
> > +#define MEMMOVE_INIT \
> > +    "movl " __ASM_NAME( "sse2_supported" ) ", %eax\n\t" \
> > +    "cmp $0, %eax\n\t" \
>
> In general you can't access global variables that way, it's not
> compatible with PIC. I'd suggest doing that part from C code.

I've sent a fixed version that does the check on C side. It has some 
impact on performance but I guess it can be ignored.

Thanks,
Piotr