ARB fragment programs use texture unit numbers directly, unlike GLSL which has an extra indirection. If a fragment program only uses one texture assigned to GL_TEXTURE1, SamplersUsed will only contain a single bit, which would make us only upload a single surface/sampler state entry. However, it needs to be the second entry.
Using ffs() instead of _mesa_bitcount() solves this. For ARB programs, this makes num_samplers the ID of the highest texture unit used. Since GLSL uses consecutive integers, ffs() should give the same result. Fixes a regression since 85e8e9e000732908b259a7e2cbc1724a1be2d447, which broke piglit test fp-fragment-position. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=54098 Signed-off-by: Kenneth Graunke <kenn...@whitecape.org> --- src/mesa/drivers/dri/i965/brw_wm_sampler_state.c | 2 +- src/mesa/drivers/dri/i965/brw_wm_surface_state.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c b/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c index 610ef34..795c9ae 100644 --- a/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c +++ b/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c @@ -341,7 +341,7 @@ brw_upload_samplers(struct brw_context *brw) GLbitfield SamplersUsed = vs->SamplersUsed | fs->SamplersUsed; - brw->sampler.count = _mesa_bitcount(SamplersUsed); + brw->sampler.count = ffs(SamplersUsed); if (brw->sampler.count == 0) return; diff --git a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c index eefa427..6a69349 100644 --- a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c +++ b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c @@ -1250,7 +1250,7 @@ brw_update_texture_surfaces(struct brw_context *brw) struct gl_program *vs = (struct gl_program *) brw->vertex_program; struct gl_program *fs = (struct gl_program *) brw->fragment_program; - unsigned num_samplers = _mesa_bitcount(vs->SamplersUsed | fs->SamplersUsed); + unsigned num_samplers = ffs(vs->SamplersUsed | fs->SamplersUsed); for (unsigned s = 0; s < num_samplers; s++) { brw->vs.surf_offset[SURF_INDEX_VS_TEXTURE(s)] = 0; -- 1.7.11.4 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
