ffmpeg/tests/checkasm/aacpsdsp.c
Martin Storsjö aad0e26f93 checkasm: aacpsdsp: Tolerate extra intermediate precision in stereo_interpolate
The stereo_interpolate functions add h_step to the values h
BUF_SIZE times. Within the stereo_interpolate C functions, the
values h (h0-h3, h00-h13) are declared as local float variables,
but the compiler is free to keep them in a register with extra
precision.

If the accumulation is rounded to 32 bit float precision after
each step, the less significant bits of h_step end up ignored
and the sum can deviate, affecting the end result more than
the currently set EPS.

By clearing the log2(BUF_SIZE) lower bits of h_step, we make sure
that the accumulation shouldn't differ significantly, regardless
of any extra precision in the accmulating register/variable.

This fixes the aacpsdsp checkasm test when built with clang for
mingw/x86_32.

Signed-off-by: Martin Storsjö <martin@martin.st>
2019-12-18 15:15:29 +02:00

262 lines
9.0 KiB
C

/*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "libavcodec/aacpsdsp.h"
#include "libavutil/intfloat.h"
#include "checkasm.h"
#define N 32
#define STRIDE 128
#define BUF_SIZE (N * STRIDE)
#define randomize(buf, len) do { \
int i; \
for (i = 0; i < len; i++) { \
const INTFLOAT f = (INTFLOAT)rnd() / UINT_MAX; \
(buf)[i] = f; \
} \
} while (0)
#define EPS 0.005
static void clear_less_significant_bits(INTFLOAT *buf, int len, int bits)
{
int i;
for (i = 0; i < len; i++) {
union av_intfloat32 u = { .f = buf[i] };
u.i &= (0xffffffff << bits);
buf[i] = u.f;
}
}
static void test_add_squares(void)
{
LOCAL_ALIGNED_16(INTFLOAT, dst0, [BUF_SIZE]);
LOCAL_ALIGNED_16(INTFLOAT, dst1, [BUF_SIZE]);
LOCAL_ALIGNED_16(INTFLOAT, src, [BUF_SIZE], [2]);
declare_func(void, INTFLOAT *dst,
const INTFLOAT (*src)[2], int n);
randomize((INTFLOAT *)src, BUF_SIZE * 2);
randomize(dst0, BUF_SIZE);
memcpy(dst1, dst0, BUF_SIZE * sizeof(INTFLOAT));
call_ref(dst0, src, BUF_SIZE);
call_new(dst1, src, BUF_SIZE);
if (!float_near_abs_eps_array(dst0, dst1, EPS, BUF_SIZE))
fail();
bench_new(dst1, src, BUF_SIZE);
}
static void test_mul_pair_single(void)
{
LOCAL_ALIGNED_16(INTFLOAT, dst0, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, dst1, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, src0, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, src1, [BUF_SIZE]);
declare_func(void, INTFLOAT (*dst)[2],
INTFLOAT (*src0)[2], INTFLOAT *src1, int n);
randomize((INTFLOAT *)src0, BUF_SIZE * 2);
randomize(src1, BUF_SIZE);
call_ref(dst0, src0, src1, BUF_SIZE);
call_new(dst1, src0, src1, BUF_SIZE);
if (!float_near_abs_eps_array((float *)dst0, (float *)dst1, EPS, BUF_SIZE * 2))
fail();
bench_new(dst1, src0, src1, BUF_SIZE);
}
static void test_hybrid_analysis(void)
{
LOCAL_ALIGNED_16(INTFLOAT, dst0, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, dst1, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, in, [13], [2]);
LOCAL_ALIGNED_16(INTFLOAT, filter, [N], [8][2]);
declare_func(void, INTFLOAT (*out)[2], INTFLOAT (*in)[2],
const INTFLOAT (*filter)[8][2],
ptrdiff_t stride, int n);
randomize((INTFLOAT *)in, 13 * 2);
randomize((INTFLOAT *)filter, N * 8 * 2);
randomize((INTFLOAT *)dst0, BUF_SIZE * 2);
memcpy(dst1, dst0, BUF_SIZE * 2 * sizeof(INTFLOAT));
call_ref(dst0, in, filter, STRIDE, N);
call_new(dst1, in, filter, STRIDE, N);
if (!float_near_abs_eps_array((float *)dst0, (float *)dst1, EPS, BUF_SIZE * 2))
fail();
bench_new(dst1, in, filter, STRIDE, N);
}
static void test_hybrid_analysis_ileave(void)
{
LOCAL_ALIGNED_16(INTFLOAT, in, [2], [38][64]);
LOCAL_ALIGNED_16(INTFLOAT, out0, [91], [32][2]);
LOCAL_ALIGNED_16(INTFLOAT, out1, [91], [32][2]);
declare_func(void, INTFLOAT (*out)[32][2], INTFLOAT L[2][38][64],
int i, int len);
randomize((INTFLOAT *)out0, 91 * 32 * 2);
randomize((INTFLOAT *)in, 2 * 38 * 64);
memcpy(out1, out0, 91 * 32 * 2 * sizeof(INTFLOAT));
/* len is hardcoded to 32 as that's the only value used in
libavcodec. asm functions are likely to be optimized
hardcoding this value in their loops and could fail with
anything else.
i is hardcoded to the two values currently used by the
aac decoder because the arm neon implementation is
micro-optimized for them and will fail for almost every
other value. */
call_ref(out0, in, 3, 32);
call_new(out1, in, 3, 32);
/* the function just moves data around, so memcmp is enough */
if (memcmp(out0, out1, 91 * 32 * 2 * sizeof(INTFLOAT)))
fail();
call_ref(out0, in, 5, 32);
call_new(out1, in, 5, 32);
if (memcmp(out0, out1, 91 * 32 * 2 * sizeof(INTFLOAT)))
fail();
bench_new(out1, in, 3, 32);
}
static void test_hybrid_synthesis_deint(void)
{
LOCAL_ALIGNED_16(INTFLOAT, out0, [2], [38][64]);
LOCAL_ALIGNED_16(INTFLOAT, out1, [2], [38][64]);
LOCAL_ALIGNED_16(INTFLOAT, in, [91], [32][2]);
declare_func(void, INTFLOAT out[2][38][64], INTFLOAT (*in)[32][2],
int i, int len);
randomize((INTFLOAT *)in, 91 * 32 * 2);
randomize((INTFLOAT *)out0, 2 * 38 * 64);
memcpy(out1, out0, 2 * 38 * 64 * sizeof(INTFLOAT));
/* len is hardcoded to 32 as that's the only value used in
libavcodec. asm functions are likely to be optimized
hardcoding this value in their loops and could fail with
anything else.
i is hardcoded to the two values currently used by the
aac decoder because the arm neon implementation is
micro-optimized for them and will fail for almost every
other value. */
call_ref(out0, in, 3, 32);
call_new(out1, in, 3, 32);
/* the function just moves data around, so memcmp is enough */
if (memcmp(out0, out1, 2 * 38 * 64 * sizeof(INTFLOAT)))
fail();
call_ref(out0, in, 5, 32);
call_new(out1, in, 5, 32);
if (memcmp(out0, out1, 2 * 38 * 64 * sizeof(INTFLOAT)))
fail();
bench_new(out1, in, 3, 32);
}
static void test_stereo_interpolate(PSDSPContext *psdsp)
{
int i;
LOCAL_ALIGNED_16(INTFLOAT, l, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, r, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, l0, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, r0, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, l1, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, r1, [BUF_SIZE], [2]);
LOCAL_ALIGNED_16(INTFLOAT, h, [2], [4]);
LOCAL_ALIGNED_16(INTFLOAT, h_step, [2], [4]);
declare_func(void, INTFLOAT (*l)[2], INTFLOAT (*r)[2],
INTFLOAT h[2][4], INTFLOAT h_step[2][4], int len);
randomize((INTFLOAT *)l, BUF_SIZE * 2);
randomize((INTFLOAT *)r, BUF_SIZE * 2);
for (i = 0; i < 2; i++) {
if (check_func(psdsp->stereo_interpolate[i], "ps_stereo_interpolate%s", i ? "_ipdopd" : "")) {
memcpy(l0, l, BUF_SIZE * 2 * sizeof(INTFLOAT));
memcpy(l1, l, BUF_SIZE * 2 * sizeof(INTFLOAT));
memcpy(r0, r, BUF_SIZE * 2 * sizeof(INTFLOAT));
memcpy(r1, r, BUF_SIZE * 2 * sizeof(INTFLOAT));
randomize((INTFLOAT *)h, 2 * 4);
randomize((INTFLOAT *)h_step, 2 * 4);
// Clear the least significant 14 bits of h_step, to avoid
// divergence when accumulating h_step BUF_SIZE times into
// a float variable which may or may not have extra intermediate
// precision. Therefore clear roughly log2(BUF_SIZE) less
// significant bits, to get the same result regardless of any
// extra precision in the accumulator.
clear_less_significant_bits((INTFLOAT *)h_step, 2 * 4, 14);
call_ref(l0, r0, h, h_step, BUF_SIZE);
call_new(l1, r1, h, h_step, BUF_SIZE);
if (!float_near_abs_eps_array((float *)l0, (float *)l1, EPS, BUF_SIZE * 2) ||
!float_near_abs_eps_array((float *)r0, (float *)r1, EPS, BUF_SIZE * 2))
fail();
memcpy(l1, l, BUF_SIZE * 2 * sizeof(INTFLOAT));
memcpy(r1, r, BUF_SIZE * 2 * sizeof(INTFLOAT));
bench_new(l1, r1, h, h_step, BUF_SIZE);
}
}
}
void checkasm_check_aacpsdsp(void)
{
PSDSPContext psdsp;
ff_psdsp_init(&psdsp);
if (check_func(psdsp.add_squares, "ps_add_squares"))
test_add_squares();
report("add_squares");
if (check_func(psdsp.mul_pair_single, "ps_mul_pair_single"))
test_mul_pair_single();
report("mul_pair_single");
if (check_func(psdsp.hybrid_analysis, "ps_hybrid_analysis"))
test_hybrid_analysis();
report("hybrid_analysis");
if (check_func(psdsp.hybrid_analysis_ileave, "ps_hybrid_analysis_ileave"))
test_hybrid_analysis_ileave();
report("hybrid_analysis_ileave");
if (check_func(psdsp.hybrid_synthesis_deint, "ps_hybrid_synthesis_deint"))
test_hybrid_synthesis_deint();
report("hybrid_synthesis_deint");
test_stereo_interpolate(&psdsp);
report("stereo_interpolate");
}