[Mesa-dev] [PATCH 04/59] glsl/standalone: Enable par-linking

[Iago Toral]

On Tue, 2016-10-25 at 17:59 -0700, Ian Romanick wrote:
> From: Ian Romanick <ian.d.romanick at intel.com>
> 
> If the user did not request full linking, link the shader with the
> built-in functions, inline them, and eliminate them.  Previous to
> this
> you'd see all these calls to "dot" and "max" in the output.  This
> prevented a lot of expected optimizations and cluttered the output.
> This gives it some chance of being useful.
> 
> v2: Rebase on top of Ken's "built-ins now" work.
> 
> v3: Don't do_common_optimizations if par-linking fails.  Update
> expected
> output of warnings tests to prevent 'make check' regressions.
> 
> v4: Optimize harder.  Most important, do function
> inlining.  Otherwise
> it's quite impractical for one function in a file to call another
> function in the same file.
> 
> Signed-off-by: Ian Romanick <ian.d.romanick at intel.com>
> ---
>  src/compiler/glsl/standalone.cpp                   | 43
> +++++++++++++++++++++-
>  ...-out-function-parameter-shaderout.vert.expected |  2 +
>  ...nout-function-parameter-shaderout.vert.expected |  2 +
>  .../030-array-as-function-parameter.vert.expected  |  2 +
>  4 files changed, 47 insertions(+), 2 deletions(-)
> 
> diff --git a/src/compiler/glsl/standalone.cpp
> b/src/compiler/glsl/standalone.cpp
> index 6a4432f..ecf162e 100644
> --- a/src/compiler/glsl/standalone.cpp
> +++ b/src/compiler/glsl/standalone.cpp
> @@ -38,6 +38,8 @@
>  #include "standalone.h"
>  #include "util/string_to_uint_map.h"
>  #include "util/set.h"
> +#include "linker.h"
> +#include "glsl_parser_extras.h"
>  
>  class add_neg_to_sub_visitor : public ir_hierarchical_visitor {
>  public:
> @@ -508,10 +510,47 @@ standalone_compile_shader(const struct
> standalone_options *_options,
>        }
>     }
>  
> -   if ((status == EXIT_SUCCESS) && options->do_link)  {
> +   if (status == EXIT_SUCCESS) {
>        _mesa_clear_shader_program_data(whole_program);
>  
> -      link_shaders(ctx, whole_program);
> +      if (options->do_link)  {
> +         link_shaders(ctx, whole_program);
> +      } else {
> +         struct gl_shader *const shader = whole_program->Shaders[0];
> 

It seems like you only need 'shader' to know to access 'shader->Stage'
in the code below, so maybe just copy the stage here?

> +         whole_program->LinkStatus = GL_TRUE;
> +         whole_program->_LinkedShaders[shader->Stage] =
> +            link_intrastage_shaders(whole_program /* mem_ctx */,
> +                                    ctx,
> +                                    whole_program,
> +                                    whole_program->Shaders,
> +                                    1,
> +                                    true);
> +
> +         /* Par-linking can fail, for example, if there are
> undefined external
> +          * references.
> +          */
> +         if (whole_program->_LinkedShaders[shader->Stage] != NULL) {

The expectation in this case would be that
whole_program->LinkStatus is also GL_TRUE. Maybe worth adding an assert
here to catch inconsistent error handling bugs in the linker?

Either way, this patch is:

Reviewed-by: Iago Toral Quiroga <itoral at igalia.com>

> +            struct gl_shader_compiler_options *const
> compiler_options =
> +               &ctx->Const.ShaderCompilerOptions[shader->Stage];
> +
> +            exec_list *const ir =
> +               whole_program->_LinkedShaders[shader->Stage]->ir;
> +
> +            bool progress;
> +            do {
> +               progress = do_function_inlining(ir);
> +
> +               progress = do_common_optimization(ir,
> +                                                 false,
> +                                                 false,
> +                                                 compiler_options,
> +                                                 true)
> +                  && progress;
> +            } while(progress);
> +         }
> +      }
> +
>        status = (whole_program->LinkStatus) ? EXIT_SUCCESS :
> EXIT_FAILURE;
>  
>        if (strlen(whole_program->InfoLog) > 0) {
> diff --git a/src/compiler/glsl/tests/warnings/026-out-function-
> parameter-shaderout.vert.expected
> b/src/compiler/glsl/tests/warnings/026-out-function-parameter-
> shaderout.vert.expected
> index e69de29..60d3a8a 100644
> --- a/src/compiler/glsl/tests/warnings/026-out-function-parameter-
> shaderout.vert.expected
> +++ b/src/compiler/glsl/tests/warnings/026-out-function-parameter-
> shaderout.vert.expected
> @@ -0,0 +1,2 @@
> +
> +error: unresolved reference to function `fooFunction'
> diff --git a/src/compiler/glsl/tests/warnings/027-inout-function-
> parameter-shaderout.vert.expected
> b/src/compiler/glsl/tests/warnings/027-inout-function-parameter-
> shaderout.vert.expected
> index 1724975..651818d 100644
> --- a/src/compiler/glsl/tests/warnings/027-inout-function-parameter-
> shaderout.vert.expected
> +++ b/src/compiler/glsl/tests/warnings/027-inout-function-parameter-
> shaderout.vert.expected
> @@ -1 +1,3 @@
>  0:11(14): warning: `willBeDefined' used uninitialized
> +
> +error: unresolved reference to function `fooFunction'
> diff --git a/src/compiler/glsl/tests/warnings/030-array-as-function-
> parameter.vert.expected b/src/compiler/glsl/tests/warnings/030-array-
> as-function-parameter.vert.expected
> index 21cb2c5..b1355d3 100644
> --- a/src/compiler/glsl/tests/warnings/030-array-as-function-
> parameter.vert.expected
> +++ b/src/compiler/glsl/tests/warnings/030-array-as-function-
> parameter.vert.expected
> @@ -5,3 +5,5 @@
>  0:14(20): warning: `undefinedIndex' used uninitialized
>  0:14(51): warning: `undefinedIndex' used uninitialized
>  0:14(82): warning: `undefinedIndex' used uninitialized
> +
> +error: unresolved reference to function `foo'