From 6823e12d5aa4646fc8ef0e32455104ba47f80a38 Mon Sep 17 00:00:00 2001 From: Jordan Justen Date: Mon, 17 Aug 2015 15:49:44 -0700 Subject: [PATCH] glsl/cs: Exclude gl_LocalInvocationIndex from builtin variable stripping MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit We lower gl_LocalInvocationIndex based on the extension spec formula: gl_LocalInvocationIndex = gl_LocalInvocationID.z * gl_WorkGroupSize.x * gl_WorkGroupSize.y + gl_LocalInvocationID.y * gl_WorkGroupSize.x + gl_LocalInvocationID.x; https://www.opengl.org/registry/specs/ARB/compute_shader.txt We need to set this variable in main(), even if gl_LocalInvocationIndex is not referenced by the shader. (It may be used by a linked shader.) Therefore, we can't eliminate it as a dead variable. Signed-off-by: Jordan Justen Reviewed-by: Tapani Pälli --- src/glsl/opt_dead_builtin_variables.cpp | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/src/glsl/opt_dead_builtin_variables.cpp b/src/glsl/opt_dead_builtin_variables.cpp index 90b753e..03e5789 100644 --- a/src/glsl/opt_dead_builtin_variables.cpp +++ b/src/glsl/opt_dead_builtin_variables.cpp @@ -72,6 +72,13 @@ optimize_dead_builtin_variables(exec_list *instructions, * gl_GlobalInvocationID = * gl_WorkGroupID * gl_WorkGroupSize + gl_LocalInvocationID * + * Similarly, we initialize gl_LocalInvocationIndex in the main function: + * + * gl_LocalInvocationIndex = + * gl_LocalInvocationID.z * gl_WorkGroupSize.x * gl_WorkGroupSize.y + + * gl_LocalInvocationID.y * gl_WorkGroupSize.x + + * gl_LocalInvocationID.x; + * * Matrix uniforms with "Transpose" are not eliminated because there's * an optimization pass that can turn references to the regular matrix * into references to the transpose matrix. Eliminating the transpose @@ -87,6 +94,7 @@ optimize_dead_builtin_variables(exec_list *instructions, || strcmp(var->name, "gl_WorkGroupSize") == 0 || strcmp(var->name, "gl_LocalInvocationID") == 0 || strcmp(var->name, "gl_GlobalInvocationID") == 0 + || strcmp(var->name, "gl_LocalInvocationIndex") == 0 || strstr(var->name, "Transpose") != NULL) continue; -- 2.7.4