[Mesa-dev] [PATCH 4/4] glsl: Delete linker stuff relating to built-in functions.

[Ian Romanick]

On 09/21/2016 10:20 PM, Kenneth Graunke wrote:
> Now that we generate built-in functions inline, there's no need to link
> against the built-in shader, and no built-in prototypes to consider.
> 
> This lets us delete a bunch of code.

Boy howdy.  This simplifies things quite a bit.  Pending patch 2, this
patch is

Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>

> Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
> ---
>  src/compiler/glsl/link_functions.cpp | 32 +++++++++++----------------
>  src/compiler/glsl/linker.cpp         | 42 +++---------------------------------
>  2 files changed, 16 insertions(+), 58 deletions(-)
> 
> diff --git a/src/compiler/glsl/link_functions.cpp b/src/compiler/glsl/link_functions.cpp
> index b4aae5e..e4f77be 100644
> --- a/src/compiler/glsl/link_functions.cpp
> +++ b/src/compiler/glsl/link_functions.cpp
> @@ -32,7 +32,7 @@
>  
>  static ir_function_signature *
>  find_matching_signature(const char *name, const exec_list *actual_parameters,
> -                        glsl_symbol_table *symbols, bool use_builtin);
> +                        glsl_symbol_table *symbols);
>  
>  namespace {
>  
> @@ -74,12 +74,15 @@ public:
>        assert(callee != NULL);
>        const char *const name = callee->function_name();
>  
> +      /* We don't actually need to find intrinsics; they're not real */
> +      if (callee->is_intrinsic)
> +         return visit_continue;
> +
>        /* Determine if the requested function signature already exists in the
>         * final linked shader.  If it does, use it as the target of the call.
>         */
>        ir_function_signature *sig =
> -         find_matching_signature(name, &callee->parameters, linked->symbols,
> -                                 ir->use_builtin);
> +         find_matching_signature(name, &callee->parameters, linked->symbols);
>        if (sig != NULL) {
>  	 ir->callee = sig;
>  	 return visit_continue;
> @@ -90,8 +93,7 @@ public:
>         */
>        for (unsigned i = 0; i < num_shaders; i++) {
>           sig = find_matching_signature(name, &ir->actual_parameters,
> -                                       shader_list[i]->symbols,
> -                                       ir->use_builtin);
> +                                       shader_list[i]->symbols);
>           if (sig)
>              break;
>        }
> @@ -122,9 +124,7 @@ public:
>  
>        ir_function_signature *linked_sig =
>  	 f->exact_matching_signature(NULL, &callee->parameters);
> -      if ((linked_sig == NULL)
> -	  || ((linked_sig != NULL)
> -	      && (linked_sig->is_builtin() != ir->use_builtin))) {
> +      if (linked_sig == NULL) {
>  	 linked_sig = new(linked) ir_function_signature(callee->return_type);
>  	 f->add_signature(linked_sig);
>        }
> @@ -314,22 +314,16 @@ private:
>   */
>  ir_function_signature *
>  find_matching_signature(const char *name, const exec_list *actual_parameters,
> -                        glsl_symbol_table *symbols, bool use_builtin)
> +                        glsl_symbol_table *symbols)
>  {
>     ir_function *const f = symbols->get_function(name);
>  
>     if (f) {
>        ir_function_signature *sig =
> -         f->matching_signature(NULL, actual_parameters, use_builtin);
> -
> -      if (sig && (sig->is_defined || sig->is_intrinsic)) {
> -         /* If this function expects to bind to a built-in function and the
> -          * signature that we found isn't a built-in, keep looking.  Also keep
> -          * looking if we expect a non-built-in but found a built-in.
> -          */
> -         if (use_builtin == sig->is_builtin())
> -            return sig;
> -      }
> +         f->matching_signature(NULL, actual_parameters, false);
> +
> +      if (sig && (sig->is_defined || sig->is_intrinsic))
> +         return sig;
>     }
>  
>     return NULL;
> diff --git a/src/compiler/glsl/linker.cpp b/src/compiler/glsl/linker.cpp
> index 606d006..929a653 100644
> --- a/src/compiler/glsl/linker.cpp
> +++ b/src/compiler/glsl/linker.cpp
> @@ -2098,14 +2098,13 @@ link_intrastage_shaders(void *mem_ctx,
>  	       continue;
>  
>  	    foreach_in_list(ir_function_signature, sig, &f->signatures) {
> -	       if (!sig->is_defined || sig->is_builtin())
> +	       if (!sig->is_defined)
>  		  continue;
>  
>  	       ir_function_signature *other_sig =
>  		  other->exact_matching_signature(NULL, &sig->parameters);
>  
> -	       if ((other_sig != NULL) && other_sig->is_defined
> -		   && !other_sig->is_builtin()) {
> +	       if (other_sig != NULL && other_sig->is_defined) {
>  		  linker_error(prog, "function `%s' is multiply defined\n",
>  			       f->name);
>  		  return NULL;
> @@ -2171,42 +2170,7 @@ link_intrastage_shaders(void *mem_ctx,
>  					      insertion_point, true, linked);
>     }
>  
> -   /* Check if any shader needs built-in functions. */
> -   bool need_builtins = false;
> -   for (unsigned i = 0; i < num_shaders; i++) {
> -      if (shader_list[i]->info.uses_builtin_functions) {
> -         need_builtins = true;
> -         break;
> -      }
> -   }
> -
> -   bool ok;
> -   if (need_builtins) {
> -      /* Make a temporary array one larger than shader_list, which will hold
> -       * the built-in function shader as well.
> -       */
> -      gl_shader **linking_shaders = (gl_shader **)
> -         calloc(num_shaders + 1, sizeof(gl_shader *));
> -
> -      ok = linking_shaders != NULL;
> -
> -      if (ok) {
> -         memcpy(linking_shaders, shader_list, num_shaders * sizeof(gl_shader *));
> -         _mesa_glsl_initialize_builtin_functions();
> -         linking_shaders[num_shaders] = _mesa_glsl_get_builtin_function_shader();
> -
> -         ok = link_function_calls(prog, linked, linking_shaders, num_shaders + 1);
> -
> -         free(linking_shaders);
> -      } else {
> -         _mesa_error_no_memory(__func__);
> -      }
> -   } else {
> -      ok = link_function_calls(prog, linked, shader_list, num_shaders);
> -   }
> -
> -
> -   if (!ok) {
> +   if (!link_function_calls(prog, linked, shader_list, num_shaders)) {
>        _mesa_delete_linked_shader(ctx, linked);
>        return NULL;
>     }
>