mesa: renumber shader indices according to their placement in pipeline

See my explanation in mtypes.h.

v2: don't do this in gallium
v3: also updated the comment at the gl_shader_type definition

Reviewed-by: Ian Romanick <[email protected]>

2 files changed, 8 insertions, 5 deletions

diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 1f62e2c9c9e..9ca45617330 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -2173,13 +2173,16 @@ struct gl_shader
 
 /**
  * Shader stages. Note that these will become 5 with tessellation.
- * These MUST have the same values as gallium's PIPE_SHADER_*
+ *
+ * The order must match how shaders are ordered in the pipeline.
+ * The GLSL linker assumes that if i<j, then the j-th shader is
+ * executed later than the i-th shader.
  */
 typedef enum
 {
    MESA_SHADER_VERTEX = 0,
-   MESA_SHADER_FRAGMENT = 1,
-   MESA_SHADER_GEOMETRY = 2,
+   MESA_SHADER_GEOMETRY = 1,
+   MESA_SHADER_FRAGMENT = 2,
    MESA_SHADER_TYPES = 3
 } gl_shader_type;
 
diff --git a/src/mesa/main/shaderobj.h b/src/mesa/main/shaderobj.h
index 5ce85cfdeba..de1c9fcaf1e 100644
--- a/src/mesa/main/shaderobj.h
+++ b/src/mesa/main/shaderobj.h
@@ -123,8 +123,8 @@ _mesa_shader_index_to_type(GLuint i)
 {
    static const GLenum enums[MESA_SHADER_TYPES] = {
       GL_VERTEX_SHADER,
-      GL_FRAGMENT_SHADER,
-      GL_GEOMETRY_SHADER ,
+      GL_GEOMETRY_SHADER,
+      GL_FRAGMENT_SHADER
    };
    if (i >= MESA_SHADER_TYPES)
       return 0;