[FFmpeg-devel] [PATCH 2/3] checkasm/blockdsp: use smallest allowed aligned buffers for fill_block_tab tests

[Andreas Rheinhardt]

James Almer:
> The requirement is either 8 or 16 bytes alignment, not 32.
> This should help finding bugs in asm implementations.
> 
> Signed-off-by: James Almer <jamrial at gmail.com>
> ---
>  tests/checkasm/blockdsp.c | 23 +++++++++--------------
>  1 file changed, 9 insertions(+), 14 deletions(-)
> 
> diff --git a/tests/checkasm/blockdsp.c b/tests/checkasm/blockdsp.c
> index ab87fc8fa4..f67a38d302 100644
> --- a/tests/checkasm/blockdsp.c
> +++ b/tests/checkasm/blockdsp.c
> @@ -29,11 +29,6 @@
>  #include "libavutil/intreadwrite.h"
>  #include "libavutil/mem_internal.h"
>  
> -typedef struct {
> -    const char *name;
> -    int size;
> -} test;
> -
>  #define randomize_buffers(size)             \
>      do {                                    \
>          int i;                              \
> @@ -58,18 +53,18 @@ do {                                                                \
>  } while (0)
>  
>  static void check_fill(BlockDSPContext *h){
> -    const test tests[] = {
> -        {"fill_block_tab[0]", 16},
> -        {"fill_block_tab[1]", 8},
> -    };
> -    LOCAL_ALIGNED_32(uint8_t, buf0, [16 * 16]);
> -    LOCAL_ALIGNED_32(uint8_t, buf1, [16 * 16]);
> +    LOCAL_ALIGNED_16(uint8_t, buf0_16, [16 * 16]);
> +    LOCAL_ALIGNED_16(uint8_t, buf1_16, [16 * 16]);
> +    LOCAL_ALIGNED_8(uint8_t, buf0_8, [8 * 8]);
> +    LOCAL_ALIGNED_8(uint8_t, buf1_8, [8 * 8]);
>  
> -    for (size_t t = 0; t < FF_ARRAY_ELEMS(tests); ++t) {
> -        int n = tests[t].size;
> +    for (int t = 0; t < 2; ++t) {
> +        uint8_t *buf0 = t ? buf0_8 : buf0_16;
> +        uint8_t *buf1 = t ? buf1_8 : buf1_16;
> +        int n = 16 - 8 * t;
>          declare_func(void, uint8_t *block, uint8_t value,
>                       ptrdiff_t line_size, int h);
> -        if (check_func(h->fill_block_tab[t], "blockdsp.%s", tests[t].name)) {
> +        if (check_func(h->fill_block_tab[t], "blockdsp.fill_block_tab[%d]", t)) {
>              uint8_t value = rnd();
>              memset(buf0, 0, sizeof(*buf0) * n * n);
>              memset(buf1, 0, sizeof(*buf0) * n * n);

1. I wouldn't be surprised if the *_8 buffers were still 16 byte
aligned. You should probably force 8 byte alignment by using a 16
byte-aligned buffer with an offset of eight.
2. Can you also extend this test to actually test the case of stride !=
width? (And negative strides.)

- Andreas