diff options
Diffstat (limited to 'system/mmx/pixel_gain.s')
| -rw-r--r-- | system/mmx/pixel_gain.s | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/system/mmx/pixel_gain.s b/system/mmx/pixel_gain.s new file mode 100644 index 0000000..5cd5057 --- /dev/null +++ b/system/mmx/pixel_gain.s @@ -0,0 +1,83 @@ +# Pure Data Packet mmx routine. +# Copyright (c) by Tom Schouten <pdp@zzz.kotnet.org> +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +# +.globl pixel_gain +.type pixel_gain,@function + +# mmx rgba pixel gain +# void asmtest(char *pixelarray, int32 nbpixels, int *rgba_gain) +# gains are 7.9 fixed point for rgba + +pixel_gain: + pushl %ebp + movl %esp, %ebp + push %esi + push %edi + + movl 8(%ebp), %esi # pixel array offset + movl 12(%ebp), %ecx # nb of elements + movl 16(%ebp), %edi # int16[4] array of gains + + prefetch (%esi) + + emms + sarl $2, %ecx # process 4 pixels per loop iteration + jz .exit + movq (%edi), %mm7 # read gain array from memory + jmp .loop_gain + + .align 16 + .loop_gain: + + prefetch 128(%esi) + movq (%esi), %mm5 # load pixel 1-2 from memory + movq 8(%esi), %mm6 # load pixel 3-4 from memory + pxor %mm0, %mm0 # zero mm0 - mm3 + pxor %mm1, %mm1 + pxor %mm2, %mm2 + pxor %mm3, %mm3 + punpcklbw %mm5, %mm0 # unpack 1st pixel into 8.8 bit ints + punpckhbw %mm5, %mm1 # unpack 2nd + punpcklbw %mm6, %mm2 # unpack 3rd + punpckhbw %mm6, %mm3 # unpack 4th + psrlw $0x1, %mm0 # shift right to clear sign bit 9.7 + psrlw $0x1, %mm1 + psrlw $0x1, %mm2 + psrlw $0x1, %mm3 + + pmulhw %mm7, %mm0 # multiply 1st pixel 9.7 * 7.9 -> 16.0 + pmulhw %mm7, %mm1 # multiply 2nd + pmulhw %mm7, %mm2 # multiply 3rd + pmulhw %mm7, %mm3 # multiply 4th + + packuswb %mm1, %mm0 # pack & saturate to 8bit vector + movq %mm0, (%esi) # store result in memory + packuswb %mm3, %mm2 # pack & saturate to 8bit vector + movq %mm2, 8(%esi) # store result in memory + + addl $16, %esi # increment source pointer + decl %ecx + jnz .loop_gain # loop + + .exit: + emms + + pop %edi + pop %esi + leave + ret + |