[Mesa-dev] [PATCH 04/14] glsl: Basic support for built-in intrinsics.

[Ian Romanick]

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

On 10/01/2013 07:15 PM, Francisco Jerez wrote:
> Fix the linker to deal with intrinsic functions which are undefined
> all the way down to the driver back-end, and introduce intrinsic
> definition helpers in the built-in generator.
> 
> We still need to figure out what kind of interface we want for drivers
> to communicate to the GLSL front-end which of the supported intrinsics
> should use a default GLSL implementation and which should use a
> hardware-specific override.  As there's no default GLSL implementation
> for atomic ops, this seems like something we can worry about later on.
> ---
>  src/glsl/builtin_functions.cpp | 21 ++++++++++++++++++---
>  src/glsl/ir.cpp                |  4 ++--
>  src/glsl/ir.h                  |  6 ++++++
>  src/glsl/link_functions.cpp    | 16 ++++++++++------
>  4 files changed, 36 insertions(+), 11 deletions(-)
> 
> diff --git a/src/glsl/builtin_functions.cpp b/src/glsl/builtin_functions.cpp
> index 72054e0..03efb6d 100644
> --- a/src/glsl/builtin_functions.cpp
> +++ b/src/glsl/builtin_functions.cpp
> @@ -339,6 +339,7 @@ private:
>     ir_variable *gl_Vertex;
>  
>     void create_shader();
> +   void create_intrinsics();
>     void create_builtins();
>  
>     /**
> @@ -576,6 +577,7 @@ builtin_builder::initialize()
>  
>     mem_ctx = ralloc_context(NULL);
>     create_shader();
> +   create_intrinsics();
>     create_builtins();
>  }
>  
> @@ -613,6 +615,15 @@ builtin_builder::create_shader()
>  /** @} */
>  
>  /**
> + * Create ir_function and ir_function_signature objects for each
> + * intrinsic.
> + */
> +void
> +builtin_builder::create_intrinsics()
> +{
> +}
> +
> +/**
>   * Create ir_function and ir_function_signature objects for each built-in.
>   *
>   * Contains a list of every available built-in.
> @@ -1865,8 +1876,6 @@ builtin_builder::add_function(const char *name, ...)
>        if (sig == NULL)
>           break;
>  
> -      sig->is_defined = true;
> -
>        if (false) {
>           exec_list stuff;
>           stuff.push_tail(sig);
> @@ -1964,7 +1973,13 @@ builtin_builder::new_sig(const glsl_type *return_type,
>  #define MAKE_SIG(return_type, avail, ...)  \
>     ir_function_signature *sig =               \
>        new_sig(return_type, avail, __VA_ARGS__);      \
> -   ir_factory body(&sig->body, mem_ctx);
> +   ir_factory body(&sig->body, mem_ctx);             \
> +   sig->is_defined = true;
> +
> +#define MAKE_INTRINSIC(return_type, avail, ...)      \
> +   ir_function_signature *sig =                      \
> +      new_sig(return_type, avail, __VA_ARGS__);      \
> +   sig->is_intrinsic = true;
>  
>  ir_function_signature *
>  builtin_builder::unop(builtin_available_predicate avail,
> diff --git a/src/glsl/ir.cpp b/src/glsl/ir.cpp
> index d65d8dc..02563e7 100644
> --- a/src/glsl/ir.cpp
> +++ b/src/glsl/ir.cpp
> @@ -1633,8 +1633,8 @@ ir_variable::determine_interpolation_mode(bool flat_shade)
>  
>  ir_function_signature::ir_function_signature(const glsl_type *return_type,
>                                               builtin_available_predicate b)
> -   : return_type(return_type), is_defined(false), builtin_avail(b),
> -     _function(NULL)
> +   : return_type(return_type), is_defined(false), is_intrinsic(false),
> +     builtin_avail(b), _function(NULL)
>  {
>     this->ir_type = ir_type_function_signature;
>     this->origin = NULL;
> diff --git a/src/glsl/ir.h b/src/glsl/ir.h
> index fd12ae6..b87819c 100644
> --- a/src/glsl/ir.h
> +++ b/src/glsl/ir.h
> @@ -694,6 +694,12 @@ public:
>     /** Whether or not this function signature is a built-in. */
>     bool is_builtin() const;
>  
> +   /**
> +    * Whether or not this function is an intrinsic to be implemented
> +    * by the driver.
> +    */
> +   bool is_intrinsic;
> +
>     /** Whether or not a built-in is available for this shader. */
>     bool is_builtin_available(const _mesa_glsl_parse_state *state) const;
>  
> diff --git a/src/glsl/link_functions.cpp b/src/glsl/link_functions.cpp
> index b1a68fd..c8531ed 100644
> --- a/src/glsl/link_functions.cpp
> +++ b/src/glsl/link_functions.cpp
> @@ -155,14 +155,17 @@ public:
>  
>        linked_sig->replace_parameters(&formal_parameters);
>  
> -      foreach_list_const(node, &sig->body) {
> -	 const ir_instruction *const original = (ir_instruction *) node;
> +      if (sig->is_defined) {
> +         foreach_list_const(node, &sig->body) {
> +            const ir_instruction *const original = (ir_instruction *) node;
>  
> -	 ir_instruction *copy = original->clone(linked, ht);
> -	 linked_sig->body.push_tail(copy);
> +            ir_instruction *copy = original->clone(linked, ht);
> +            linked_sig->body.push_tail(copy);
> +         }
> +
> +         linked_sig->is_defined = true;
>        }
>  
> -      linked_sig->is_defined = true;
>        hash_table_dtor(ht);
>  
>        /* Patch references inside the function to things outside the function
> @@ -294,7 +297,8 @@ find_matching_signature(const char *name, const exec_list *actual_parameters,
>        ir_function_signature *sig =
>           f->matching_signature(NULL, actual_parameters);
>  
> -      if ((sig == NULL) || !sig->is_defined)
> +      if ((sig == NULL) ||
> +          (!sig->is_defined && !sig->is_intrinsic))
>  	 continue;
>  
>        /* If this function expects to bind to a built-in function and the
>