i965: Clean up context constant initialization code.

This was getting pretty out of hand, and with compute partially in place
and tessellation on the way, it was only going to get worse.

This patch makes a "stage exists?" predicate and a "number of stages"
count and uses them to clean up a lot of calculations.  We can just
loop over shader stages and set things for the ones that exist.  For
combined counts, we can just multiply by the number of stages.

It also tries to organize a little bit.

We should probably use _mesa_has_geometry_shaders/tessellation/compute
here, but we can't because ctx->Version isn't initialized yet.  Perhaps
that could be fixed in the future.

No change in "glxinfo -l" on Broadwell.

v2: Drop stray compute shader hunk.  Mark stage_exists as const.

Signed-off-by: Kenneth Graunke <[email protected]>
Reviewed-by: Topi Pohjolainen <[email protected]>
Reviewed-by: Jordan Justen <[email protected]>

1 files changed, 54 insertions, 80 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_context.c b/src/mesa/drivers/dri/i965/brw_context.c
index 2db99c74b8e..e70ad982f48 100644
--- a/src/mesa/drivers/dri/i965/brw_context.c
+++ b/src/mesa/drivers/dri/i965/brw_context.c
@@ -322,64 +322,81 @@ static void
 brw_initialize_context_constants(struct brw_context *brw)
 {
    struct gl_context *ctx = &brw->ctx;
+   const struct brw_compiler *compiler = brw->intelScreen->compiler;
+
+   const bool stage_exists[MESA_SHADER_STAGES] = {
+      [MESA_SHADER_VERTEX] = true,
+      [MESA_SHADER_TESS_CTRL] = false,
+      [MESA_SHADER_TESS_EVAL] = false,
+      [MESA_SHADER_GEOMETRY] = brw->gen >= 6,
+      [MESA_SHADER_FRAGMENT] = true,
+      [MESA_SHADER_COMPUTE] = _mesa_extension_override_enables.ARB_compute_shader,
+   };
+
+   unsigned num_stages = 0;
+   for (int i = 0; i < MESA_SHADER_STAGES; i++) {
+      if (stage_exists[i])
+         num_stages++;
+   }
 
    unsigned max_samplers =
       brw->gen >= 8 || brw->is_haswell ? BRW_MAX_TEX_UNIT : 16;
 
+   ctx->Const.MaxDualSourceDrawBuffers = 1;
+   ctx->Const.MaxDrawBuffers = BRW_MAX_DRAW_BUFFERS;
+   ctx->Const.MaxCombinedShaderOutputResources =
+      MAX_IMAGE_UNITS + BRW_MAX_DRAW_BUFFERS;
+
    ctx->Const.QueryCounterBits.Timestamp = 36;
 
+   ctx->Const.MaxTextureCoordUnits = 8; /* Mesa limit */
+   ctx->Const.MaxImageUnits = MAX_IMAGE_UNITS;
+   ctx->Const.MaxRenderbufferSize = 8192;
+   ctx->Const.MaxTextureLevels = MIN2(14 /* 8192 */, MAX_TEXTURE_LEVELS);
+   ctx->Const.Max3DTextureLevels = 12; /* 2048 */
+   ctx->Const.MaxCubeTextureLevels = 14; /* 8192 */
+   ctx->Const.MaxArrayTextureLayers = brw->gen >= 7 ? 2048 : 512;
+   ctx->Const.MaxTextureMbytes = 1536;
+   ctx->Const.MaxTextureRectSize = 1 << 12;
+   ctx->Const.MaxTextureMaxAnisotropy = 16.0;
    ctx->Const.StripTextureBorder = true;
+   if (brw->gen >= 7)
+      ctx->Const.MaxProgramTextureGatherComponents = 4;
+   else if (brw->gen == 6)
+      ctx->Const.MaxProgramTextureGatherComponents = 1;
 
    ctx->Const.MaxUniformBlockSize = 65536;
+
    for (int i = 0; i < MESA_SHADER_STAGES; i++) {
       struct gl_program_constants *prog = &ctx->Const.Program[i];
+
+      if (!stage_exists[i])
+         continue;
+
+      prog->MaxTextureImageUnits = max_samplers;
+
       prog->MaxUniformBlocks = BRW_MAX_UBO;
       prog->MaxCombinedUniformComponents =
          prog->MaxUniformComponents +
          ctx->Const.MaxUniformBlockSize / 4 * prog->MaxUniformBlocks;
+
+      prog->MaxAtomicCounters = MAX_ATOMIC_COUNTERS;
+      prog->MaxAtomicBuffers = BRW_MAX_ABO;
+      prog->MaxImageUniforms = compiler->scalar_stage[i] ? BRW_MAX_IMAGES : 0;
+      prog->MaxShaderStorageBlocks = BRW_MAX_SSBO;
    }
 
-   ctx->Const.MaxDualSourceDrawBuffers = 1;
-   ctx->Const.MaxDrawBuffers = BRW_MAX_DRAW_BUFFERS;
-   ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits = max_samplers;
-   ctx->Const.MaxTextureCoordUnits = 8; /* Mesa limit */
    ctx->Const.MaxTextureUnits =
       MIN2(ctx->Const.MaxTextureCoordUnits,
            ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits);
-   ctx->Const.Program[MESA_SHADER_VERTEX].MaxTextureImageUnits = max_samplers;
-   if (brw->gen >= 6)
-      ctx->Const.Program[MESA_SHADER_GEOMETRY].MaxTextureImageUnits = max_samplers;
-   else
-      ctx->Const.Program[MESA_SHADER_GEOMETRY].MaxTextureImageUnits = 0;
-   if (_mesa_extension_override_enables.ARB_compute_shader) {
-      ctx->Const.Program[MESA_SHADER_COMPUTE].MaxTextureImageUnits = BRW_MAX_TEX_UNIT;
-      ctx->Const.MaxUniformBufferBindings += BRW_MAX_UBO;
-   } else {
-      ctx->Const.Program[MESA_SHADER_COMPUTE].MaxTextureImageUnits = 0;
-   }
-   ctx->Const.MaxCombinedTextureImageUnits =
-      ctx->Const.Program[MESA_SHADER_VERTEX].MaxTextureImageUnits +
-      ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits +
-      ctx->Const.Program[MESA_SHADER_GEOMETRY].MaxTextureImageUnits +
-      ctx->Const.Program[MESA_SHADER_COMPUTE].MaxTextureImageUnits;
-
-   ctx->Const.MaxTextureLevels = 14; /* 8192 */
-   if (ctx->Const.MaxTextureLevels > MAX_TEXTURE_LEVELS)
-      ctx->Const.MaxTextureLevels = MAX_TEXTURE_LEVELS;
-   ctx->Const.Max3DTextureLevels = 12; /* 2048 */
-   ctx->Const.MaxCubeTextureLevels = 14; /* 8192 */
-   ctx->Const.MaxTextureMbytes = 1536;
-
-   if (brw->gen >= 7)
-      ctx->Const.MaxArrayTextureLayers = 2048;
-   else
-      ctx->Const.MaxArrayTextureLayers = 512;
 
-   ctx->Const.MaxTextureRectSize = 1 << 12;
+   ctx->Const.MaxUniformBufferBindings = num_stages * BRW_MAX_UBO;
+   ctx->Const.MaxCombinedAtomicBuffers = num_stages * BRW_MAX_ABO;
+   ctx->Const.MaxCombinedShaderStorageBlocks = num_stages * BRW_MAX_SSBO;
+   ctx->Const.MaxShaderStorageBufferBindings = num_stages * BRW_MAX_SSBO;
+   ctx->Const.MaxCombinedTextureImageUnits = num_stages * max_samplers;
+   ctx->Const.MaxCombinedImageUniforms = num_stages * BRW_MAX_IMAGES;
 
-   ctx->Const.MaxTextureMaxAnisotropy = 16.0;
-
-   ctx->Const.MaxRenderbufferSize = 8192;
 
    /* Hardware only supports a limited number of transform feedback buffers.
     * So we need to override the Mesa default (which is based only on software
@@ -427,6 +444,7 @@ brw_initialize_context_constants(struct brw_context *brw)
    ctx->Const.MaxColorTextureSamples = max_samples;
    ctx->Const.MaxDepthTextureSamples = max_samples;
    ctx->Const.MaxIntegerSamples = max_samples;
+   ctx->Const.MaxImageSamples = 0;
 
    /* gen6_set_sample_maps() sets SampleMap{2,4,8}x variables which are used
     * to map indices of rectangular grid to sample numbers within a pixel.
@@ -436,11 +454,6 @@ brw_initialize_context_constants(struct brw_context *brw)
     */
    gen6_set_sample_maps(ctx);
 
-   if (brw->gen >= 7)
-      ctx->Const.MaxProgramTextureGatherComponents = 4;
-   else if (brw->gen == 6)
-      ctx->Const.MaxProgramTextureGatherComponents = 1;
-
    ctx->Const.MinLineWidth = 1.0;
    ctx->Const.MinLineWidthAA = 1.0;
    if (brw->gen >= 6) {
@@ -511,30 +524,6 @@ brw_initialize_context_constants(struct brw_context *brw)
    ctx->Const.Program[MESA_SHADER_VERTEX].HighInt = ctx->Const.Program[MESA_SHADER_VERTEX].LowInt;
    ctx->Const.Program[MESA_SHADER_VERTEX].MediumInt = ctx->Const.Program[MESA_SHADER_VERTEX].LowInt;
 
-   if (brw->gen >= 7) {
-      ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxAtomicCounters = MAX_ATOMIC_COUNTERS;
-      ctx->Const.Program[MESA_SHADER_VERTEX].MaxAtomicCounters = MAX_ATOMIC_COUNTERS;
-      ctx->Const.Program[MESA_SHADER_GEOMETRY].MaxAtomicCounters = MAX_ATOMIC_COUNTERS;
-      ctx->Const.Program[MESA_SHADER_COMPUTE].MaxAtomicCounters = MAX_ATOMIC_COUNTERS;
-      ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxAtomicBuffers = BRW_MAX_ABO;
-      ctx->Const.Program[MESA_SHADER_VERTEX].MaxAtomicBuffers = BRW_MAX_ABO;
-      ctx->Const.Program[MESA_SHADER_GEOMETRY].MaxAtomicBuffers = BRW_MAX_ABO;
-      ctx->Const.Program[MESA_SHADER_COMPUTE].MaxAtomicBuffers = BRW_MAX_ABO;
-      ctx->Const.MaxCombinedAtomicBuffers = 3 * BRW_MAX_ABO;
-
-      ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxImageUniforms =
-         BRW_MAX_IMAGES;
-      ctx->Const.Program[MESA_SHADER_VERTEX].MaxImageUniforms =
-         (brw->intelScreen->compiler->scalar_stage[MESA_SHADER_VERTEX] ? BRW_MAX_IMAGES : 0);
-      ctx->Const.Program[MESA_SHADER_COMPUTE].MaxImageUniforms =
-         BRW_MAX_IMAGES;
-      ctx->Const.MaxImageUnits = MAX_IMAGE_UNITS;
-      ctx->Const.MaxCombinedShaderOutputResources =
-         MAX_IMAGE_UNITS + BRW_MAX_DRAW_BUFFERS;
-      ctx->Const.MaxImageSamples = 0;
-      ctx->Const.MaxCombinedImageUniforms = 3 * BRW_MAX_IMAGES;
-   }
-
    /* Gen6 converts quads to polygon in beginning of 3D pipeline,
     * but we're not sure how it's actually done for vertex order,
     * that affect provoking vertex decision. Always use last vertex
@@ -586,21 +575,6 @@ brw_initialize_context_constants(struct brw_context *brw)
    ctx->Const.TextureBufferOffsetAlignment = 16;
    ctx->Const.MaxTextureBufferSize = 128 * 1024 * 1024;
 
-   /* FIXME: Tessellation stages are not yet supported in i965, so
-    * MaxCombinedShaderStorageBlocks doesn't take them into account.
-    */
-   ctx->Const.Program[MESA_SHADER_VERTEX].MaxShaderStorageBlocks = BRW_MAX_SSBO;
-   ctx->Const.Program[MESA_SHADER_GEOMETRY].MaxShaderStorageBlocks = BRW_MAX_SSBO;
-   ctx->Const.Program[MESA_SHADER_TESS_EVAL].MaxShaderStorageBlocks = 0;
-   ctx->Const.Program[MESA_SHADER_TESS_CTRL].MaxShaderStorageBlocks = 0;
-   ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxShaderStorageBlocks = BRW_MAX_SSBO;
-   ctx->Const.Program[MESA_SHADER_COMPUTE].MaxShaderStorageBlocks = BRW_MAX_SSBO;
-   ctx->Const.MaxCombinedShaderStorageBlocks = BRW_MAX_SSBO * 3;
-   ctx->Const.MaxShaderStorageBufferBindings = BRW_MAX_SSBO * 3;
-
-   if (_mesa_extension_override_enables.ARB_compute_shader)
-      ctx->Const.MaxShaderStorageBufferBindings += BRW_MAX_SSBO;
-
    if (brw->gen >= 6) {
       ctx->Const.MaxVarying = 32;
       ctx->Const.Program[MESA_SHADER_VERTEX].MaxOutputComponents = 128;