[Piglit] [PATCH 1/4] pbo-read-argb8888: make it endian-safe

[Ilia Mirkin]

On Mon, Mar 28, 2016 at 9:25 AM, Oded Gabbay <oded.gabbay at gmail.com> wrote:
> In this test we use GL_BGRA + GL_UNSIGNED_BYTE. However, the probe
> function receives two 4-byte values to compare, expected and
> observed. This is wrong as the correct way to compare
> array_of_bytes (GL_UNSIGNED_BYTE) in an endian-safe way is by comparing
> memory (and not values).
>
> This patch fixes this bug by changing the function to receive two
> pointers instead of values. It also corrects the way the expected values
> are constructed to be in endian-safe way for array-of-bytes
>
> This fixes the test in llvmpipe, softpipe and r600g in big-endian machine.
>
> Signed-off-by: Oded Gabbay <oded.gabbay at gmail.com>
> ---
>  tests/general/pbo-read-argb8888.c | 24 ++++++++++++++++++------
>  1 file changed, 18 insertions(+), 6 deletions(-)
>
> diff --git a/tests/general/pbo-read-argb8888.c b/tests/general/pbo-read-argb8888.c
> index 99b4b3b..e053d0d 100644
> --- a/tests/general/pbo-read-argb8888.c
> +++ b/tests/general/pbo-read-argb8888.c
> @@ -43,12 +43,17 @@ PIGLIT_GL_TEST_CONFIG_BEGIN
>  PIGLIT_GL_TEST_CONFIG_END
>
>  static GLboolean
> -probe(int x, int y, uint32_t expected, uint32_t observed)
> +probe(int x, int y, uint32_t *expected, uint32_t *observed)
>  {
> -       if ((expected & 0xffffff) != (observed & 0xffffff)) {
> +       uint8_t *p_exp = (uint8_t *) expected;
> +       uint8_t *p_obs = (uint8_t *) observed;
> +
> +       if (p_exp[0] != p_obs[0] ||
> +                p_exp[1] != p_obs[1] ||
> +                p_exp[2] != p_obs[2]) {
>                 printf("Probe color at (%i,%i)\n", x, y);
> -               printf("  Expected: 0x%08x\n", expected);
> -               printf("  Observed: 0x%08x\n", observed);
> +               printf("  Expected: 0x%08x\n", *expected);
> +               printf("  Observed: 0x%08x\n", *observed);
>
>                 return GL_FALSE;
>         } else {
> @@ -63,8 +68,15 @@ piglit_display(void)
>         static float red[]   = {1.0, 0.0, 0.0, 0.0};
>         static float green[] = {0.0, 1.0, 0.0, 0.0};
>         uint32_t *addr;
> +       GLuint exp_green = 0, exp_red = 0;
> +       GLbyte *ptr;
>         GLuint pbo;
>
> +       ptr = (GLbyte *) &exp_green;
> +       ptr[1] = 0xFF;
> +       ptr = (GLbyte *) &exp_red;
> +       ptr[2] = 0xFF;

Could you do something like

GLbyte exp_green[4] = {0x00, 0xFF, 0x00, 0x00};
... exp_red ...

And then change addr to be an unsigned char * and change probe() to
take two of those instead? That seems like it would convey what's
actually being tested more clearly...

> +
>         glGenBuffersARB(1, &pbo);
>         glBindBufferARB(GL_PIXEL_PACK_BUFFER, pbo);
>         glBufferDataARB(GL_PIXEL_PACK_BUFFER, 2 * 4, NULL, GL_STREAM_DRAW_ARB);
> @@ -84,8 +96,8 @@ piglit_display(void)
>
>         addr = glMapBufferARB(GL_PIXEL_PACK_BUFFER, GL_READ_ONLY_ARB);
>
> -       pass &= probe(10, 10, 0x0000ff00, addr[0]);
> -       pass &= probe(10, 10, 0x00ff0000, addr[1]);
> +       pass &= probe(10, 10, &exp_green, &addr[0]);
> +       pass &= probe(10, 10, &exp_red, &addr[1]);
>
>         glUnmapBufferARB(GL_PIXEL_PACK_BUFFER);
>
> --
> 2.5.5
>
> _______________________________________________
> Piglit mailing list
> Piglit at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/piglit