diff options
author | Ian Romanick <[email protected]> | 2013-10-04 10:46:29 -0700 |
---|---|---|
committer | Ian Romanick <[email protected]> | 2013-10-22 15:23:30 -0700 |
commit | 63974c0f5b26e369a790505af6820d4bbcf451b2 (patch) | |
tree | 227b453fc6e459d5cb04ae6a5baad96c5454134f /src/glsl/linker.cpp | |
parent | 1eee0a9f016a1049869f4677f5919186ee3785a2 (diff) |
glsl: Simplify the interface to link_invalidate_variable_locations
The unit tests added in the previous commits prove some things about the
state of some internal data structures. The most important of these is
that all built-in input and output variables have explicit_location
set. This means that link_invalidate_variable_locations doesn't need to
know the range of non-generic shader inputs or outputs. It can simply
reset location state depending on whether explicit_location is set.
There are two additional assumptions that were already implicit in the
code that comments now document.
- ir_variable::is_unmatched_generic_inout is only used by the linker
when connecting outputs from one shader stage to inputs of another
shader stage.
- Any varying that has explicit_location set must be a built-in. This
will be true until GL_ARB_separate_shader_objects is supported.
As a result, the input_base and output_base parameters to
link_invalidate_variable_locations are no longer necessary, and the code
for resetting locations and setting is_unmatched_generic_inout can be
simplified.
Signed-off-by: Ian Romanick <[email protected]>
Reviewed-by: Paul Berry <[email protected]>
Diffstat (limited to 'src/glsl/linker.cpp')
-rw-r--r-- | src/glsl/linker.cpp | 48 |
1 files changed, 24 insertions, 24 deletions
diff --git a/src/glsl/linker.cpp b/src/glsl/linker.cpp index bf96d606488..b23c31a166b 100644 --- a/src/glsl/linker.cpp +++ b/src/glsl/linker.cpp @@ -366,8 +366,7 @@ parse_program_resource_name(const GLchar *name, void -link_invalidate_variable_locations(exec_list *ir, int input_base, - int output_base) +link_invalidate_variable_locations(exec_list *ir) { foreach_list(node, ir) { ir_variable *const var = ((ir_instruction *) node)->as_variable(); @@ -375,26 +374,30 @@ link_invalidate_variable_locations(exec_list *ir, int input_base, if (var == NULL) continue; - int base; - switch (var->mode) { - case ir_var_shader_in: - base = input_base; - break; - case ir_var_shader_out: - base = output_base; - break; - default: - continue; - } - - /* Only assign locations for generic attributes / varyings / etc. + /* Only assign locations for variables that lack an explicit location. + * Explicit locations are set for all built-in variables, generic vertex + * shader inputs (via layout(location=...)), and generic fragment shader + * outputs (also via layout(location=...)). */ - if ((var->location >= base) && !var->explicit_location) + if (!var->explicit_location) { var->location = -1; + var->location_frac = 0; + } - if ((var->location == -1) && !var->explicit_location) { + /* ir_variable::is_unmatched_generic_inout is used by the linker while + * connecting outputs from one stage to inputs of the next stage. + * + * There are two implicit assumptions here. First, we assume that any + * built-in variable (i.e., non-generic in or out) will have + * explicit_location set. Second, we assume that any generic in or out + * will not have explicit_location set. + * + * This second assumption will only be valid until + * GL_ARB_separate_shader_objects is supported. When that extension is + * implemented, this function will need some modifications. + */ + if (!var->explicit_location) { var->is_unmatched_generic_inout = 1; - var->location_frac = 0; } else { var->is_unmatched_generic_inout = 0; } @@ -2217,18 +2220,15 @@ link_shaders(struct gl_context *ctx, struct gl_shader_program *prog) /* Mark all generic shader inputs and outputs as unpaired. */ if (prog->_LinkedShaders[MESA_SHADER_VERTEX] != NULL) { link_invalidate_variable_locations( - prog->_LinkedShaders[MESA_SHADER_VERTEX]->ir, - VERT_ATTRIB_GENERIC0, VARYING_SLOT_VAR0); + prog->_LinkedShaders[MESA_SHADER_VERTEX]->ir); } if (prog->_LinkedShaders[MESA_SHADER_GEOMETRY] != NULL) { link_invalidate_variable_locations( - prog->_LinkedShaders[MESA_SHADER_GEOMETRY]->ir, - VARYING_SLOT_VAR0, VARYING_SLOT_VAR0); + prog->_LinkedShaders[MESA_SHADER_GEOMETRY]->ir); } if (prog->_LinkedShaders[MESA_SHADER_FRAGMENT] != NULL) { link_invalidate_variable_locations( - prog->_LinkedShaders[MESA_SHADER_FRAGMENT]->ir, - VARYING_SLOT_VAR0, FRAG_RESULT_DATA0); + prog->_LinkedShaders[MESA_SHADER_FRAGMENT]->ir); } /* FINISHME: The value of the max_attribute_index parameter is |