We initialize gl_GlobalInvocationID based on the extension spec
formula:
gl_GlobalInvocationID =
gl_WorkGroupID * gl_WorkGroupSize + gl_LocalInvocationID
https://www.opengl.org/registry/specs/ARB/compute_shader.txt
Signed-off-by: Jordan Justen <jordan.l.jus...@intel.com>
Cc: Ilia Mirkin <imir...@alum.mit.edu>
---
src/glsl/builtin_variables.cpp | 58 +++++++++++++++++++++++++++++++++++++++++
src/glsl/glsl_parser_extras.cpp | 2 ++
src/glsl/ir.h | 3 +++
3 files changed, 63 insertions(+)
diff --git a/src/glsl/builtin_variables.cpp b/src/glsl/builtin_variables.cpp
index 5d9e446..8f8be90 100644
--- a/src/glsl/builtin_variables.cpp
+++ b/src/glsl/builtin_variables.cpp
@@ -22,6 +22,8 @@
*/
#include "ir.h"
+#include "ir_builder.h"
+#include "linker.h"
#include "glsl_parser_extras.h"
#include "glsl_symbol_table.h"
#include "main/core.h"
@@ -1056,6 +1058,7 @@ builtin_variable_generator::generate_cs_special_vars()
"gl_LocalInvocationID");
add_system_value(SYSTEM_VALUE_WORK_GROUP_ID, glsl_type::uvec3_type,
"gl_WorkGroupID");
+ add_variable("gl_GlobalInvocationID", glsl_type::uvec3_type, ir_var_auto,
0);
/* TODO: finish this. */
}
@@ -1212,3 +1215,58 @@ _mesa_glsl_initialize_variables(exec_list *instructions,
break;
}
}
+
+
+/**
+ * Initialize compute shader variables with values that are derived from other
+ * compute shader variable.
+ */
+static void
+initialize_cs_derived_variables(gl_shader *shader,
+ ir_function_signature *const main_sig)
+{
+ assert(shader->Stage == MESA_SHADER_COMPUTE);
+
+ ir_variable *gl_GlobalInvocationID =
+ shader->symbols->get_variable("gl_GlobalInvocationID");
+ assert(gl_GlobalInvocationID);
+ ir_variable *gl_WorkGroupID =
+ shader->symbols->get_variable("gl_WorkGroupID");
+ assert(gl_WorkGroupID);
+ ir_variable *gl_WorkGroupSize =
+ shader->symbols->get_variable("gl_WorkGroupSize");
+ assert(gl_WorkGroupSize);
+ ir_variable *gl_LocalInvocationID =
+ shader->symbols->get_variable("gl_LocalInvocationID");
+ assert(gl_LocalInvocationID);
+
+ /* gl_GlobalInvocationID =
+ * gl_WorkGroupID * gl_WorkGroupSize + gl_LocalInvocationID
+ */
+ ir_instruction *inst =
+ ir_builder::assign(gl_GlobalInvocationID,
+ ir_builder::add(ir_builder::mul(gl_WorkGroupID,
+ gl_WorkGroupSize),
+ gl_LocalInvocationID));
+ main_sig->body.push_head(inst);
+}
+
+
+/**
+ * Initialize builtin variables with values based on other builtin variables.
+ * These are initialized in the main function.
+ */
+void
+_mesa_glsl_initialize_derived_variables(gl_shader *shader)
+{
+ /* We only need to set CS variables currently. */
+ if (shader->Stage != MESA_SHADER_COMPUTE)
+ return;
+
+ ir_function_signature *const main_sig =
+ _mesa_get_main_function_signature(shader);
+ if (main_sig == NULL)
+ return;
+
+ initialize_cs_derived_variables(shader, main_sig);
+}
diff --git a/src/glsl/glsl_parser_extras.cpp b/src/glsl/glsl_parser_extras.cpp
index 6440a96..eefa12a 100644
--- a/src/glsl/glsl_parser_extras.cpp
+++ b/src/glsl/glsl_parser_extras.cpp
@@ -1692,6 +1692,8 @@ _mesa_glsl_compile_shader(struct gl_context *ctx, struct
gl_shader *shader,
}
}
+ _mesa_glsl_initialize_derived_variables(shader);
+
delete state->symbols;
ralloc_free(state);
}
diff --git a/src/glsl/ir.h b/src/glsl/ir.h
index 750321e..4c88144 100644
--- a/src/glsl/ir.h
+++ b/src/glsl/ir.h
@@ -2513,6 +2513,9 @@ _mesa_glsl_initialize_variables(exec_list *instructions,
struct _mesa_glsl_parse_state *state);
extern void
+_mesa_glsl_initialize_derived_variables(gl_shader *shader);
+
+extern void
_mesa_glsl_initialize_functions(_mesa_glsl_parse_state *state);
extern void
--
2.1.4
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/mesa-dev
