ref: 6356d21a47e2547ab3c657052e36939bde047cb3
dir: /vp8/encoder/ppc/fdct_altivec.asm/
;
; 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 vp8_short_fdct4x4_ppc
.globl vp8_short_fdct8x4_ppc
.macro load_c V, LABEL, OFF, R0, R1
lis \R0, \LABEL@ha
la \R1, \LABEL@l(\R0)
lvx \V, \OFF, \R1
.endm
;# Forward and inverse DCTs are nearly identical; only differences are
;# in normalization (fwd is twice unitary, inv is half unitary)
;# and that they are of course transposes of each other.
;#
;# The following three accomplish most of implementation and
;# are used only by ppc_idct.c and ppc_fdct.c.
.macro prologue
mfspr r11, 256 ;# get old VRSAVE
oris r12, r11, 0xfffc
mtspr 256, r12 ;# set VRSAVE
stwu r1,-32(r1) ;# create space on the stack
li r6, 16
load_c v0, dct_tab, 0, r9, r10
lvx v1, r6, r10
addi r10, r10, 32
lvx v2, 0, r10
lvx v3, r6, r10
load_c v4, ppc_dctperm_tab, 0, r9, r10
load_c v5, ppc_dctperm_tab, r6, r9, r10
load_c v6, round_tab, 0, r10, r9
.endm
.macro epilogue
addi r1, r1, 32 ;# recover stack
mtspr 256, r11 ;# reset old VRSAVE
.endm
;# Do horiz xf on two rows of coeffs v8 = a0 a1 a2 a3 b0 b1 b2 b3.
;# a/A are the even rows 0,2 b/B are the odd rows 1,3
;# For fwd transform, indices are horizontal positions, then frequencies.
;# For inverse transform, frequencies then positions.
;# The two resulting A0..A3 B0..B3 are later combined
;# and vertically transformed.
.macro two_rows_horiz Dst
vperm v9, v8, v8, v4 ;# v9 = a2 a3 a0 a1 b2 b3 b0 b1
vmsumshm v10, v0, v8, v6
vmsumshm v10, v1, v9, v10
vsraw v10, v10, v7 ;# v10 = A0 A1 B0 B1
vmsumshm v11, v2, v8, v6
vmsumshm v11, v3, v9, v11
vsraw v11, v11, v7 ;# v11 = A2 A3 B2 B3
vpkuwum v10, v10, v11 ;# v10 = A0 A1 B0 B1 A2 A3 B2 B3
vperm \Dst, v10, v10, v5 ;# Dest = A0 B0 A1 B1 A2 B2 A3 B3
.endm
;# Vertical xf on two rows. DCT values in comments are for inverse transform;
;# forward transform uses transpose.
.macro two_rows_vert Ceven, Codd
vspltw v8, \Ceven, 0 ;# v8 = c00 c10 or c02 c12 four times
vspltw v9, \Codd, 0 ;# v9 = c20 c30 or c22 c32 ""
vmsumshm v8, v8, v12, v6
vmsumshm v8, v9, v13, v8
vsraw v10, v8, v7
vspltw v8, \Codd, 1 ;# v8 = c01 c11 or c03 c13
vspltw v9, \Ceven, 1 ;# v9 = c21 c31 or c23 c33
vmsumshm v8, v8, v12, v6
vmsumshm v8, v9, v13, v8
vsraw v8, v8, v7
vpkuwum v8, v10, v8 ;# v8 = rows 0,1 or 2,3
.endm
.macro two_rows_h Dest
stw r0, 0(r8)
lwz r0, 4(r3)
stw r0, 4(r8)
lwzux r0, r3,r5
stw r0, 8(r8)
lwz r0, 4(r3)
stw r0, 12(r8)
lvx v8, 0,r8
two_rows_horiz \Dest
.endm
.align 2
;# r3 short *input
;# r4 short *output
;# r5 int pitch
vp8_short_fdct4x4_ppc:
prologue
vspltisw v7, 14 ;# == 14, fits in 5 signed bits
addi r8, r1, 0
lwz r0, 0(r3)
two_rows_h v12 ;# v12 = H00 H10 H01 H11 H02 H12 H03 H13
lwzux r0, r3, r5
two_rows_h v13 ;# v13 = H20 H30 H21 H31 H22 H32 H23 H33
lvx v6, r6, r9 ;# v6 = Vround
vspltisw v7, -16 ;# == 16 == -16, only low 5 bits matter
two_rows_vert v0, v1
stvx v8, 0, r4
two_rows_vert v2, v3
stvx v8, r6, r4
epilogue
blr
.align 2
;# r3 short *input
;# r4 short *output
;# r5 int pitch
vp8_short_fdct8x4_ppc:
prologue
vspltisw v7, 14 ;# == 14, fits in 5 signed bits
addi r8, r1, 0
addi r10, r3, 0
lwz r0, 0(r3)
two_rows_h v12 ;# v12 = H00 H10 H01 H11 H02 H12 H03 H13
lwzux r0, r3, r5
two_rows_h v13 ;# v13 = H20 H30 H21 H31 H22 H32 H23 H33
lvx v6, r6, r9 ;# v6 = Vround
vspltisw v7, -16 ;# == 16 == -16, only low 5 bits matter
two_rows_vert v0, v1
stvx v8, 0, r4
two_rows_vert v2, v3
stvx v8, r6, r4
;# Next block
addi r3, r10, 8
addi r4, r4, 32
lvx v6, 0, r9 ;# v6 = Hround
vspltisw v7, 14 ;# == 14, fits in 5 signed bits
addi r8, r1, 0
lwz r0, 0(r3)
two_rows_h v12 ;# v12 = H00 H10 H01 H11 H02 H12 H03 H13
lwzux r0, r3, r5
two_rows_h v13 ;# v13 = H20 H30 H21 H31 H22 H32 H23 H33
lvx v6, r6, r9 ;# v6 = Vround
vspltisw v7, -16 ;# == 16 == -16, only low 5 bits matter
two_rows_vert v0, v1
stvx v8, 0, r4
two_rows_vert v2, v3
stvx v8, r6, r4
epilogue
blr
.data
.align 4
ppc_dctperm_tab:
.byte 4,5,6,7, 0,1,2,3, 12,13,14,15, 8,9,10,11
.byte 0,1,4,5, 2,3,6,7, 8,9,12,13, 10,11,14,15
.align 4
dct_tab:
.short 23170, 23170,-12540,-30274, 23170, 23170,-12540,-30274
.short 23170, 23170, 30274, 12540, 23170, 23170, 30274, 12540
.short 23170,-23170, 30274,-12540, 23170,-23170, 30274,-12540
.short -23170, 23170, 12540,-30274,-23170, 23170, 12540,-30274
.align 4
round_tab:
.long (1 << (14-1)), (1 << (14-1)), (1 << (14-1)), (1 << (14-1))
.long (1 << (16-1)), (1 << (16-1)), (1 << (16-1)), (1 << (16-1))