From 4e120fbbbd087c3acbad6ce2e8c7b1262a5c8632 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?R=C3=A9mi=20Denis-Courmont?= Date: Sat, 1 Jun 2024 21:32:56 +0300 Subject: [PATCH] lavc/vp8dsp: add R-V V vp7_idct_dc_add4y As with idct_dc_add, most of the code is shared with, and replaces, the previous VP8 function. To improve performance, we break down the 16x4 matrix into 4 rows, rather than 4 squares. Thus strided loads and stores are avoided, and the 4 DC calculations are vectored. Unfortunately this requires a vector gather to splat the DC values, but overall this is still a win for performance: T-Head C908: vp7_idct_dc_add4y_c: 7.2 vp7_idct_dc_add4y_rvv_i32: 2.2 vp8_idct_dc_add4y_c: 6.2 vp8_idct_dc_add4y_rvv_i32: 2.2 (before) vp8_idct_dc_add4y_rvv_i32: 1.7 SpacemiT X60: vp7_idct_dc_add4y_c: 6.2 vp7_idct_dc_add4y_rvv_i32: 2.0 vp8_idct_dc_add4y_c: 5.5 vp8_idct_dc_add4y_rvv_i32: 2.5 (before) vp8_idct_dc_add4y_rvv_i32: 1.7 I also tried to provision the DC values using indexed loads. It ends up slower overall, especially for VP7, as we then have to compute 16 DC's instead of just 4. --- libavcodec/riscv/vp7dsp_init.c | 2 ++ libavcodec/riscv/vp7dsp_rvv.S | 16 ++++++++++++ libavcodec/riscv/vp8dsp_rvv.S | 46 ++++++++++++++++++++++++++-------- 3 files changed, 54 insertions(+), 10 deletions(-) diff --git a/libavcodec/riscv/vp7dsp_init.c b/libavcodec/riscv/vp7dsp_init.c index 491874483f..fa5fb9d2ae 100644 --- a/libavcodec/riscv/vp7dsp_init.c +++ b/libavcodec/riscv/vp7dsp_init.c @@ -28,6 +28,7 @@ void ff_vp7_luma_dc_wht_rvv(int16_t block[4][4][16], int16_t dc[16]); void ff_vp7_idct_add_rvv(uint8_t *dst, int16_t block[16], ptrdiff_t stride); void ff_vp78_idct_dc_add_rvv(uint8_t *, int16_t block[16], ptrdiff_t, int dc); +void ff_vp7_idct_dc_add4y_rvv(uint8_t *dst, int16_t block[4][16], ptrdiff_t); static void ff_vp7_idct_dc_add_rvv(uint8_t *dst, int16_t block[16], ptrdiff_t stride) @@ -49,6 +50,7 @@ av_cold void ff_vp7dsp_init_riscv(VP8DSPContext *c) c->vp8_idct_add = ff_vp7_idct_add_rvv; #endif c->vp8_idct_dc_add = ff_vp7_idct_dc_add_rvv; + c->vp8_idct_dc_add4y = ff_vp7_idct_dc_add4y_rvv; } #endif } diff --git a/libavcodec/riscv/vp7dsp_rvv.S b/libavcodec/riscv/vp7dsp_rvv.S index 2a4c404bbb..39b23c2e79 100644 --- a/libavcodec/riscv/vp7dsp_rvv.S +++ b/libavcodec/riscv/vp7dsp_rvv.S @@ -127,3 +127,19 @@ func ff_vp7_idct_add_rvv, zve32x ret endfunc #endif + +func ff_vp7_idct_dc_add4y_rvv, zve32x + li t0, 32 + vsetivli zero, 4, e16, mf2, ta, ma + li t1, 23170 + vlse16.v v8, (a1), t0 # block[0..3][0] + vwmul.vx v0, v8, t1 + li t2, 0x20000 + vsetvli zero, zero, e32, m1, ta, ma + vsra.vi v0, v0, 14 + vmul.vx v0, v0, t1 + vadd.vx v0, v0, t2 + vsetvli zero, zero, e16, mf2, ta, ma + vnsra.wi v8, v0, 18 # 4x DC + tail ff_vp78_idct_dc_add4y_rvv +endfunc diff --git a/libavcodec/riscv/vp8dsp_rvv.S b/libavcodec/riscv/vp8dsp_rvv.S index 7a3ab576e9..8ea0a0c9bd 100644 --- a/libavcodec/riscv/vp8dsp_rvv.S +++ b/libavcodec/riscv/vp8dsp_rvv.S @@ -105,6 +105,7 @@ func ff_vp8_idct_dc_add_rvv, zve32x # fall through endfunc +# a3 = DC func ff_vp78_idct_dc_add_rvv, zve32x csrwi vxrm, 0 vsetivli zero, 4, e8, mf4, ta, ma @@ -121,6 +122,41 @@ func ff_vp78_idct_dc_add_rvv, zve32x ret endfunc +func ff_vp8_idct_dc_add4y_rvv, zve32x + li t0, 32 + vsetivli zero, 4, e16, mf2, ta, ma + vlse16.v v8, (a1), t0 + vadd.vi v8, v8, 4 + vsra.vi v8, v8, 3 + # fall through +endfunc + + .variant_cc ff_vp78_idct_dc_add4y_rvv +# v8 = [dc0, dc1, dc2, dc3] +func ff_vp78_idct_dc_add4y_rvv, zve32x + vsetivli zero, 16, e16, m2, ta, ma + vid.v v4 + vsrl.vi v4, v4, 2 + vrgather.vv v0, v8, v4 # replicate each DC four times + vsetvli zero, zero, e8, m1, ta, ma + li a4, 4 +1: + vle8.v v8, (a0) + addi a4, a4, -1 + vwaddu.wv v16, v0, v8 + sh zero, (a1) + vsetvli zero, zero, e16, m2, ta, ma + vmax.vx v16, v16, zero + addi a1, a1, 32 + vsetvli zero, zero, e8, m1, ta, ma + vnclipu.wi v8, v16, 0 + vse8.v v8, (a0) + add a0, a0, a2 + bnez a4, 1b + + ret +endfunc + .macro vp8_idct_dc_add vlse32.v v0, (a0), a2 lh a5, 0(a1) @@ -143,16 +179,6 @@ endfunc addi a1, a1, 32 .endm -func ff_vp8_idct_dc_add4y_rvv, zve32x - vsetivli zero, 4, e8, mf4, ta, ma - .rept 3 - vp8_idct_dc_addy - .endr - vp8_idct_dc_add - - ret -endfunc - func ff_vp8_idct_dc_add4uv_rvv, zve32x vsetivli zero, 4, e8, mf4, ta, ma vp8_idct_dc_addy