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x86: bswapdsp: Don't treat 32-bit integers as 64-bit

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The upper halves are not guaranteed to be zero in x86-64.

Also use `test` instead of `and` when the result isn't used for anything other
than as a branch condition, this allows some register moves to be eliminated.

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
This commit is contained in:
Henrik Gramner 2015-07-16 00:10:27 +02:00 committed by Luca Barbato
parent f5ee23004d
commit a344e5d094
1 changed files with 10 additions and 13 deletions
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23
libavcodec/x86/bswapdsp.asm
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@ -28,8 +28,8 @@ SECTION_TEXT
; %1 = aligned/unaligned
%macro BSWAP_LOOPS 1
mov r3, r2
sar r2, 3
mov r3d, r2d
sar r2d, 3
jz .left4_%1
.loop8_%1:
mov%1 m0, [r1 + 0]
@ -57,11 +57,11 @@ SECTION_TEXT
%endif
add r0, 32
add r1, 32
dec r2
dec r2d
jnz .loop8_%1
.left4_%1:
mov r2, r3
and r3, 4
mov r2d, r3d
test r3d, 4
jz .left
mov%1 m0, [r1]
%if cpuflag(ssse3)
@ -84,13 +84,11 @@ SECTION_TEXT
%macro BSWAP32_BUF 0
%if cpuflag(ssse3)
cglobal bswap32_buf, 3,4,3
mov r3, r1
mova m2, [pb_bswap32]
%else
cglobal bswap32_buf, 3,4,5
mov r3, r1
%endif
and r3, 15
test r1, 15
jz .start_align
BSWAP_LOOPS u
jmp .left
@ -98,8 +96,7 @@ cglobal bswap32_buf, 3,4,5
BSWAP_LOOPS a
.left:
%if cpuflag(ssse3)
mov r3, r2
and r2, 2
test r2d, 2
jz .left1
movq m0, [r1]
pshufb m0, m2
@ -107,13 +104,13 @@ cglobal bswap32_buf, 3,4,5
add r1, 8
add r0, 8
.left1:
and r3, 1
test r2d, 1
jz .end
mov r2d, [r1]
bswap r2d
mov [r0], r2d
%else
and r2, 3
and r2d, 3
jz .end
.loop2:
mov r3d, [r1]
@ -121,7 +118,7 @@ cglobal bswap32_buf, 3,4,5
mov [r0], r3d
add r1, 4
add r0, 4
dec r2
dec r2d
jnz .loop2
%endif
.end: