diff options
| -rw-r--r-- | src/compiler/glsl/lower_variable_index_to_cond_assign.cpp | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/src/compiler/glsl/lower_variable_index_to_cond_assign.cpp b/src/compiler/glsl/lower_variable_index_to_cond_assign.cpp index 278d5450bfb..fcb12d1b77d 100644 --- a/src/compiler/glsl/lower_variable_index_to_cond_assign.cpp +++ b/src/compiler/glsl/lower_variable_index_to_cond_assign.cpp @@ -385,6 +385,26 @@ public: case ir_var_const_in: return this->lower_temps; + case ir_var_system_value: + /* There are only a few system values that have array types: + * + * gl_TessLevelInner[] + * gl_TessLevelOuter[] + * gl_SampleMaskIn[] + * + * The tessellation factor arrays are lowered to vec4/vec2s + * by lower_tess_level() before this pass occurs, so we'll + * never see them here. + * + * The only remaining case is gl_SampleMaskIn[], which has + * a length of ceil(ctx->Const.MaxSamples / 32). Most hardware + * supports no more than 32 samples, in which case our lowering + * produces a single read of gl_SampleMaskIn[0]. Even with 64x + * MSAA, the array length is only 2, so the lowering is fairly + * efficient. Therefore, lower unconditionally. + */ + return true; + case ir_var_shader_in: /* The input array size is unknown at compiler time for non-patch * inputs in TCS and TES. The arrays are sized to |