libvpx: Add VP9 decoder.

source/libvpx/vp9/common/ppc/vp9_idctllm_altivec.asm

Index: source/libvpx/vp9/common/ppc/vp9_idctllm_altivec.asm
===================================================================
--- source/libvpx/vp9/common/ppc/vp9_idctllm_altivec.asm	(revision 0)
+++ source/libvpx/vp9/common/ppc/vp9_idctllm_altivec.asm	(revision 0)
@@ -0,0 +1,189 @@
+;
+;  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
+;
+;  Use of this source code is governed by a BSD-style license
+;  that can be found in the LICENSE file in the root of the source
+;  tree. An additional intellectual property rights grant can be found
+;  in the file PATENTS.  All contributing project authors may
+;  be found in the AUTHORS file in the root of the source tree.
+;
+
+
+    .globl short_idct4x4llm_ppc
+
+.macro load_c V, LABEL, OFF, R0, R1
+    lis     \R0, \LABEL@ha
+    la      \R1, \LABEL@l(\R0)
+    lvx     \V, \OFF, \R1
+.endm
+
+;# r3 short *input
+;# r4 short *output
+;# r5 int pitch
+    .align 2
+short_idct4x4llm_ppc:
+    mfspr   r11, 256            ;# get old VRSAVE
+    oris    r12, r11, 0xfff8
+    mtspr   256, r12            ;# set VRSAVE
+
+    load_c v8, sinpi8sqrt2, 0, r9, r10
+    load_c v9, cospi8sqrt2minus1, 0, r9, r10
+    load_c v10, hi_hi, 0, r9, r10
+    load_c v11, lo_lo, 0, r9, r10
+    load_c v12, shift_16, 0, r9, r10
+
+    li      r10,  16
+    lvx     v0,   0, r3         ;# input ip[0], ip[ 4]
+    lvx     v1, r10, r3         ;# input ip[8], ip[12]
+
+    ;# first pass
+    vupkhsh v2, v0
+    vupkhsh v3, v1
+    vaddsws v6, v2, v3          ;# a1 = ip[0]+ip[8]
+    vsubsws v7, v2, v3          ;# b1 = ip[0]-ip[8]
+
+    vupklsh v0, v0
+    vmulosh v4, v0, v8
+    vsraw   v4, v4, v12
+    vaddsws v4, v4, v0          ;# ip[ 4] * sin(pi/8) * sqrt(2)
+
+    vupklsh v1, v1
+    vmulosh v5, v1, v9
+    vsraw   v5, v5, v12         ;# ip[12] * cos(pi/8) * sqrt(2)
+    vaddsws v5, v5, v1
+
+    vsubsws v4, v4, v5          ;# c1
+
+    vmulosh v3, v1, v8
+    vsraw   v3, v3, v12
+    vaddsws v3, v3, v1          ;# ip[12] * sin(pi/8) * sqrt(2)
+
+    vmulosh v5, v0, v9
+    vsraw   v5, v5, v12         ;# ip[ 4] * cos(pi/8) * sqrt(2)
+    vaddsws v5, v5, v0
+
+    vaddsws v3, v3, v5          ;# d1
+
+    vaddsws v0, v6, v3          ;# a1 + d1
+    vsubsws v3, v6, v3          ;# a1 - d1
+
+    vaddsws v1, v7, v4          ;# b1 + c1
+    vsubsws v2, v7, v4          ;# b1 - c1
+
+    ;# transpose input
+    vmrghw  v4, v0, v1          ;# a0 b0 a1 b1
+    vmrghw  v5, v2, v3          ;# c0 d0 c1 d1
+
+    vmrglw  v6, v0, v1          ;# a2 b2 a3 b3
+    vmrglw  v7, v2, v3          ;# c2 d2 c3 d3
+
+    vperm   v0, v4, v5, v10     ;# a0 b0 c0 d0
+    vperm   v1, v4, v5, v11     ;# a1 b1 c1 d1
+
+    vperm   v2, v6, v7, v10     ;# a2 b2 c2 d2
+    vperm   v3, v6, v7, v11     ;# a3 b3 c3 d3
+
+    ;# second pass
+    vaddsws v6, v0, v2          ;# a1 = ip[0]+ip[8]
+    vsubsws v7, v0, v2          ;# b1 = ip[0]-ip[8]
+
+    vmulosh v4, v1, v8
+    vsraw   v4, v4, v12
+    vaddsws v4, v4, v1          ;# ip[ 4] * sin(pi/8) * sqrt(2)
+
+    vmulosh v5, v3, v9
+    vsraw   v5, v5, v12         ;# ip[12] * cos(pi/8) * sqrt(2)
+    vaddsws v5, v5, v3
+
+    vsubsws v4, v4, v5          ;# c1
+
+    vmulosh v2, v3, v8
+    vsraw   v2, v2, v12
+    vaddsws v2, v2, v3          ;# ip[12] * sin(pi/8) * sqrt(2)
+
+    vmulosh v5, v1, v9
+    vsraw   v5, v5, v12         ;# ip[ 4] * cos(pi/8) * sqrt(2)
+    vaddsws v5, v5, v1
+
+    vaddsws v3, v2, v5          ;# d1
+
+    vaddsws v0, v6, v3          ;# a1 + d1
+    vsubsws v3, v6, v3          ;# a1 - d1
+
+    vaddsws v1, v7, v4          ;# b1 + c1
+    vsubsws v2, v7, v4          ;# b1 - c1
+
+    vspltish v6, 4
+    vspltish v7, 3
+
+    vpkswss v0, v0, v1
+    vpkswss v1, v2, v3
+
+    vaddshs v0, v0, v6
+    vaddshs v1, v1, v6
+
+    vsrah   v0, v0, v7
+    vsrah   v1, v1, v7
+
+    ;# transpose output
+    vmrghh  v2, v0, v1          ;# a0 c0 a1 c1 a2 c2 a3 c3
+    vmrglh  v3, v0, v1          ;# b0 d0 b1 d1 b2 d2 b3 d3
+
+    vmrghh  v0, v2, v3          ;# a0 b0 c0 d0 a1 b1 c1 d1
+    vmrglh  v1, v2, v3          ;# a2 b2 c2 d2 a3 b3 c3 d3
+
+    stwu    r1,-416(r1)         ;# create space on the stack
+
+    stvx    v0,  0, r1
+    lwz     r6, 0(r1)
+    stw     r6, 0(r4)
+    lwz     r6, 4(r1)
+    stw     r6, 4(r4)
+
+    add     r4, r4, r5
+
+    lwz     r6,  8(r1)
+    stw     r6,  0(r4)
+    lwz     r6, 12(r1)
+    stw     r6,  4(r4)
+
+    add     r4, r4, r5
+
+    stvx    v1,  0, r1
+    lwz     r6, 0(r1)
+    stw     r6, 0(r4)
+    lwz     r6, 4(r1)
+    stw     r6, 4(r4)
+
+    add     r4, r4, r5
+
+    lwz     r6,  8(r1)
+    stw     r6,  0(r4)
+    lwz     r6, 12(r1)
+    stw     r6,  4(r4)
+
+    addi    r1, r1, 416         ;# recover stack
+
+    mtspr   256, r11            ;# reset old VRSAVE
+
+    blr
+
+    .align 4
+sinpi8sqrt2:
+    .short  35468, 35468, 35468, 35468, 35468, 35468, 35468, 35468
+
+    .align 4
+cospi8sqrt2minus1:
+    .short  20091, 20091, 20091, 20091, 20091, 20091, 20091, 20091
+
+    .align 4
+shift_16:
+    .long      16,    16,    16,    16
+
+    .align 4
+hi_hi:
+    .byte     0,  1,  2,  3,  4,  5,  6,  7, 16, 17, 18, 19, 20, 21, 22, 23
+
+    .align 4
+lo_lo:
+    .byte     8,  9, 10, 11, 12, 13, 14, 15, 24, 25, 26, 27, 28, 29, 30, 31