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| author | Jens Arnold <amiconn@rockbox.org> | 2007-10-18 00:14:22 +0000 |
|---|---|---|
| committer | Jens Arnold <amiconn@rockbox.org> | 2007-10-18 00:14:22 +0000 |
| commit | 1cca3ceeefaf23b6da825f20fac7f6a398d7bf80 (patch) | |
| tree | 80f14059b630e1f251a49765f3f1535d61eba180 /apps/plugins/mpegplayer | |
| parent | 7bcfa84c4a5908ad4feeb4ab508b1e053f19925d (diff) | |
| download | rockbox-1cca3ceeefaf23b6da825f20fac7f6a398d7bf80.zip rockbox-1cca3ceeefaf23b6da825f20fac7f6a398d7bf80.tar.gz rockbox-1cca3ceeefaf23b6da825f20fac7f6a398d7bf80.tar.bz2 rockbox-1cca3ceeefaf23b6da825f20fac7f6a398d7bf80.tar.xz | |
Less stack hogging in the coldfire IDCT for mpegplayer. Speedup might or might not be measurable.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@15175 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'apps/plugins/mpegplayer')
| -rw-r--r-- | apps/plugins/mpegplayer/idct_coldfire.S | 47 |
1 files changed, 23 insertions, 24 deletions
diff --git a/apps/plugins/mpegplayer/idct_coldfire.S b/apps/plugins/mpegplayer/idct_coldfire.S index 7c3626d..8db8401 100644 --- a/apps/plugins/mpegplayer/idct_coldfire.S +++ b/apps/plugins/mpegplayer/idct_coldfire.S @@ -25,11 +25,9 @@ /* The IDCT itself. * Input: %a0: block pointer - * All registers are preserved. */ + * Caller must save all registers. */ .align 2 .idct: - lea.l (-15*4,%sp), %sp - movem.l %d0-%d7/%a0-%a6, (%sp) | save all registers move.l %a0, %a6 move.l #0, %macsr | signed integer mode @@ -238,20 +236,19 @@ subq.l #1, %d3 | loop 8 times bne.w .col_loop - movem.l (%sp), %d0-%d7/%a0-%a6 | restore all registers - lea.l (15*4,%sp), %sp rts .align 2 mpeg2_idct_copy_coldfire: - lea.l (-4*4,%sp), %sp - movem.l %d2-%d4/%a2, (%sp) | save some registers - movem.l (4*4+4,%sp), %a0-%a2| %a0 - block pointer - | %a1 - destination pointer - | %a2 - stride + lea.l (-11*4,%sp), %sp + movem.l %d2-%d7/%a2-%a6, (%sp) | save some registers + move.l (11*4+4,%sp), %a0 | %a0 - block pointer for idct - bsr.w .idct | apply idct to block + bsr.w .idct | apply idct to block + movem.l (11*4+4,%sp), %a0-%a2 | %a0 - block pointer + | %a1 - destination pointer + | %a2 - stride move.l #255, %d1 | preload constant for clipping moveq.l #8, %d4 | loop counter @@ -336,22 +333,23 @@ mpeg2_idct_copy_coldfire: subq.l #1, %d4 | loop 8 times bne.w .copy_clip_loop - movem.l (%sp), %d2-%d4/%a2 | restore registers - lea.l (4*4,%sp), %sp + movem.l (%sp), %d2-%d7/%a2-%a6 + lea.l (11*4,%sp), %sp rts .align 2 mpeg2_idct_add_coldfire: - lea.l (-7*4,%sp), %sp - movem.l %d2-%d7/%a2, (%sp) | save some registers - movem.l (7*4+4,%sp), %d0/%a0-%a2| %d0 - last value - | %a0 - block pointer - | %a1 - destination pointer - | %a2 - stride + lea.l (-11*4,%sp), %sp + movem.l %d2-%d7/%a2-%a6, (%sp) + movem.l (11*4+4,%sp), %d0/%a0-%a2 | %d0 - last value + | %a0 - block pointer + | %a1 - destination pointer + | %a2 - stride + cmp.l #129, %d0 | last == 129 ? bne.b .idct_add | no: perform idct + addition - move.w (%a0), %d0 + move.w (%a0), %d0 ext.l %d0 | ((block[0] asr.l #4, %d0 | >> 4) and.l #7, %d0 | & 7) @@ -359,8 +357,9 @@ mpeg2_idct_add_coldfire: bne.w .dc_add | no: just perform addition .idct_add: - bsr.w .idct | apply idct - + bsr.w .idct | apply idct + movem.l (11*4+8,%sp), %a0-%a2 | reload arguments %a0..%a2 + move.l #255, %d2 | preload constant for clipping clr.l %d3 | used for splitting input words into bytes moveq.l #8, %d4 | loop counter @@ -569,6 +568,6 @@ mpeg2_idct_add_coldfire: bne.w .dc_clip_loop .idct_add_end: - movem.l (%sp), %d2-%d7/%a2 | restore registers - lea.l (7*4,%sp), %sp + movem.l (%sp), %d2-%d7/%a2-%a6 + lea.l (11*4,%sp), %sp rts |