[Mesa-dev] [PATCH 3/3] mesa: rework how we free gl_shader_program_data

[Timothy Arceri]

When I introduced gl_shader_program_data one of the intentions was to
fix a bug where a failed linking attempt freed data required by a
currently active program. However I seem to have failed to finish
hooking up the final steps required to have the data hang around.

Here we create a fresh instance of gl_shader_program_data every
time we link. gl_program has a reference to gl_shader_program_data
so it will be freed once the program is no longer active.

Cc: Neil Roberts <nroberts at igalia.com>
Cc: "17.2 17.3" <mesa-stable at lists.freedesktop.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102177
---
 src/mesa/main/shaderobj.c       | 71 +++++++++++++++++------------------------
 src/mesa/main/shaderobj.h       |  3 ++
 src/mesa/program/ir_to_mesa.cpp |  2 ++
 3 files changed, 35 insertions(+), 41 deletions(-)

diff --git a/src/mesa/main/shaderobj.c b/src/mesa/main/shaderobj.c
index e2103bcde49..5501a0157db 100644
--- a/src/mesa/main/shaderobj.c
+++ b/src/mesa/main/shaderobj.c
@@ -192,7 +192,30 @@ _mesa_lookup_shader_err(struct gl_context *ctx, GLuint name, const char *caller)
 /**********************************************************************/
 /*** Shader Program object functions                                ***/
 /**********************************************************************/
+static void
+free_shader_program_data(struct gl_shader_program_data *data)
+{
+   if (data->UniformStorage) {
+      for (unsigned i = 0; i < data->NumUniformStorage; ++i)
+         _mesa_uniform_detach_all_driver_storage(&data->UniformStorage[i]);
+      ralloc_free(data->UniformStorage);
+   }
+
+   assert(data->InfoLog != NULL);
+   ralloc_free(data->InfoLog);
+
+   ralloc_free(data->UniformBlocks);
+
+   ralloc_free(data->ShaderStorageBlocks);
 
+   if (data->AtomicBuffers) {
+      ralloc_free(data->AtomicBuffers);
+   }
+
+   if (data->ProgramResourceList) {
+      ralloc_free(data->ProgramResourceList);
+   }
+}
 
 void
 _mesa_reference_shader_program_data(struct gl_context *ctx,
@@ -209,6 +232,7 @@ _mesa_reference_shader_program_data(struct gl_context *ctx,
 
       if (p_atomic_dec_zero(&oldData->RefCount)) {
          assert(ctx);
+         free_shader_program_data(oldData);
          ralloc_free(oldData);
       }
 
@@ -259,14 +283,16 @@ _mesa_reference_shader_program_(struct gl_context *ctx,
    }
 }
 
-static struct gl_shader_program_data *
-create_shader_program_data()
+struct gl_shader_program_data *
+_mesa_create_shader_program_data()
 {
    struct gl_shader_program_data *data;
    data = rzalloc(NULL, struct gl_shader_program_data);
    if (data)
       data->RefCount = 1;
 
+   data->InfoLog = ralloc_strdup(data, "");
+
    return data;
 }
 
@@ -286,8 +312,6 @@ init_shader_program(struct gl_shader_program *prog)
    prog->TransformFeedback.BufferMode = GL_INTERLEAVED_ATTRIBS;
 
    exec_list_make_empty(&prog->EmptyUniformLocations);
-
-   prog->data->InfoLog = ralloc_strdup(prog->data, "");
 }
 
 /**
@@ -300,7 +324,7 @@ _mesa_new_shader_program(GLuint name)
    shProg = rzalloc(NULL, struct gl_shader_program);
    if (shProg) {
       shProg->Name = name;
-      shProg->data = create_shader_program_data();
+      shProg->data = _mesa_create_shader_program_data();
       if (!shProg->data) {
          ralloc_free(shProg);
          return NULL;
@@ -310,7 +334,6 @@ _mesa_new_shader_program(GLuint name)
    return shProg;
 }
 
-
 /**
  * Clear (free) the shader program state that gets produced by linking.
  */
@@ -325,17 +348,6 @@ _mesa_clear_shader_program_data(struct gl_context *ctx,
       }
    }
 
-   shProg->data->linked_stages = 0;
-
-   if (shProg->data->UniformStorage) {
-      for (unsigned i = 0; i < shProg->data->NumUniformStorage; ++i)
-         _mesa_uniform_detach_all_driver_storage(&shProg->data->
-                                                    UniformStorage[i]);
-      ralloc_free(shProg->data->UniformStorage);
-      shProg->data->NumUniformStorage = 0;
-      shProg->data->UniformStorage = NULL;
-   }
-
    if (shProg->UniformRemapTable) {
       ralloc_free(shProg->UniformRemapTable);
       shProg->NumUniformRemapTable = 0;
@@ -347,29 +359,7 @@ _mesa_clear_shader_program_data(struct gl_context *ctx,
       shProg->UniformHash = NULL;
    }
 
-   assert(shProg->data->InfoLog != NULL);
-   ralloc_free(shProg->data->InfoLog);
-   shProg->data->InfoLog = ralloc_strdup(shProg->data, "");
-
-   ralloc_free(shProg->data->UniformBlocks);
-   shProg->data->UniformBlocks = NULL;
-   shProg->data->NumUniformBlocks = 0;
-
-   ralloc_free(shProg->data->ShaderStorageBlocks);
-   shProg->data->ShaderStorageBlocks = NULL;
-   shProg->data->NumShaderStorageBlocks = 0;
-
-   if (shProg->data->AtomicBuffers) {
-      ralloc_free(shProg->data->AtomicBuffers);
-      shProg->data->AtomicBuffers = NULL;
-      shProg->data->NumAtomicBuffers = 0;
-   }
-
-   if (shProg->data->ProgramResourceList) {
-      ralloc_free(shProg->data->ProgramResourceList);
-      shProg->data->ProgramResourceList = NULL;
-      shProg->data->NumProgramResourceList = 0;
-   }
+   _mesa_reference_shader_program_data(ctx, &shProg->data, NULL);
 }
 
 
@@ -432,7 +422,6 @@ _mesa_delete_shader_program(struct gl_context *ctx,
                             struct gl_shader_program *shProg)
 {
    _mesa_free_shader_program_data(ctx, shProg);
-   _mesa_reference_shader_program_data(ctx, &shProg->data, NULL);
    ralloc_free(shProg);
 }
 
diff --git a/src/mesa/main/shaderobj.h b/src/mesa/main/shaderobj.h
index 97b8ce7ac23..084848e220c 100644
--- a/src/mesa/main/shaderobj.h
+++ b/src/mesa/main/shaderobj.h
@@ -100,6 +100,9 @@ _mesa_lookup_shader_program_err(struct gl_context *ctx, GLuint name,
 extern struct gl_shader_program *
 _mesa_new_shader_program(GLuint name);
 
+extern struct gl_shader_program_data *
+_mesa_create_shader_program_data(void);
+
 extern void
 _mesa_clear_shader_program_data(struct gl_context *ctx,
                                 struct gl_shader_program *shProg);
diff --git a/src/mesa/program/ir_to_mesa.cpp b/src/mesa/program/ir_to_mesa.cpp
index aa330638836..327fd61d422 100644
--- a/src/mesa/program/ir_to_mesa.cpp
+++ b/src/mesa/program/ir_to_mesa.cpp
@@ -3067,6 +3067,8 @@ _mesa_glsl_link_shader(struct gl_context *ctx, struct gl_shader_program *prog)
 
    _mesa_clear_shader_program_data(ctx, prog);
 
+   prog->data = _mesa_create_shader_program_data();
+
    prog->data->LinkStatus = linking_success;
 
    for (i = 0; i < prog->NumShaders; i++) {
-- 
2.13.6