[Mesa-dev] [v2 6/6] mesa: OES_get_program_binary functionality

[Erik Faye-Lund]

On Fri, Nov 1, 2013 at 11:35 AM, Tapani Pälli <tapani.palli at intel.com> wrote:
> On 11/01/2013 12:21 PM, Erik Faye-Lund wrote:
>>
>> On Fri, Nov 1, 2013 at 10:16 AM, Tapani Pälli <tapani.palli at intel.com>
>> wrote:
>>>
>>> Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
>>> ---
>>>   src/mesa/main/shaderapi.c | 46
>>> +++++++++++++++++++++++++++++++++++++++-------
>>>   1 file changed, 39 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/src/mesa/main/shaderapi.c b/src/mesa/main/shaderapi.c
>>> index 7da860d..67aee6b 100644
>>> --- a/src/mesa/main/shaderapi.c
>>> +++ b/src/mesa/main/shaderapi.c
>>> @@ -57,6 +57,8 @@
>>>   #include "../glsl/ir.h"
>>>   #include "../glsl/ir_uniform.h"
>>>   #include "../glsl/program.h"
>>> +#include "../glsl/ir_cache.h"
>>> +#include "git_sha1.h"
>>>
>>>   /** Define this to enable shader substitution (see below) */
>>>   #define SHADER_SUBST 0
>>> @@ -212,7 +214,6 @@ attach_shader(struct gl_context *ctx, GLuint program,
>>> GLuint shader)
>>>      struct gl_shader_program *shProg;
>>>      struct gl_shader *sh;
>>>      GLuint i, n;
>>> -
>>>      const bool same_type_disallowed = _mesa_is_gles(ctx);
>>>
>>>      shProg = _mesa_lookup_shader_program_err(ctx, program,
>>> "glAttachShader");
>>> @@ -1630,8 +1631,26 @@ _mesa_GetProgramBinary(GLuint program, GLsizei
>>> bufSize, GLsizei *length,
>>>      if (length != NULL)
>>>         *length = 0;
>>>
>>> -   (void) binaryFormat;
>>> -   (void) binary;
>>> +   size_t size = 0;
>>> +   char *data = _mesa_program_serialize(shProg, &size, MESA_GIT_SHA1);
>>> +
>>> +   /* we have more data that can fit to user given buffer */
>>> +   if (size > bufSize) {
>>> +      _mesa_error(ctx, GL_INVALID_OPERATION, __FUNCTION__);
>>> +      if (data)
>>> +         free(data);
>>> +      return;
>>> +   }
>>> +
>>> +   if (data) {
>>> +      memcpy(binary, data, size);
>>> +      free(data);
>>> +   }
>>> +
>>> +   if (length != NULL)
>>> +      *length = size;
>>> +
>>> +   *binaryFormat = 0;
>>>   }
>>>
>>>   void GLAPIENTRY
>>> @@ -1645,10 +1664,23 @@ _mesa_ProgramBinary(GLuint program, GLenum
>>> binaryFormat,
>>>      if (!shProg)
>>>         return;
>>>
>>> -   (void) binaryFormat;
>>> -   (void) binary;
>>> -   (void) length;
>>> -   _mesa_error(ctx, GL_INVALID_OPERATION, __FUNCTION__);
>>> +   if (length <= 0)
>>> +      return;
>>> +
>>> +   /* free possible existing data and initialize structure */
>>> +   _mesa_free_shader_program_data(ctx, shProg);
>>> +   _mesa_init_shader_program(ctx, shProg);
>>> +
>>> +   /* fill structure from a binary blob */
>>> +   if (_mesa_program_deserialize(shProg, binary, length, MESA_GIT_SHA1))
>>> {
>>
>>
>> Won't using the git-sha1 as a compatibility-criteria cause issues for
>> developers with local changes? I'm not so worried about this for
>> OES_get_program_binary itself, but once the shader-cache is in place
>> it sounds like a potential source of difficult to track down
>> misbehavior...
>
>
> I agree it might be too aggressive criteria but it is hard to come up with
> better and as simple.

That's not my objection. My objection is that this might give
headaches for people with local modifications to the glsl-compiler.
Local modifications does not affect the git-sha1.