mesa: Remove EXT_blend_subtract extension enable flag

All drivers remaining in Mesa support this extension.  This extension
is either required or optional features in desktop OpenGL, OpenGL ES
1.x, and OpenGL ES 2.x.

This extension was previously not supported on i810, mach64, mga,
savage, sis, and tdfx (Voodoo Banshee and Voodoo3).

Signed-off-by: Ian Romanick <[email protected]>
Reviewed-by: Brian Paul <[email protected]>
Reviewed-by: Kenneth Graunke <[email protected]>

13 files changed, 4 insertions, 19 deletions

diff --git a/src/mesa/drivers/dri/intel/intel_extensions.c b/src/mesa/drivers/dri/intel/intel_extensions.c
index 2256f4c37ae..710cc6352f0 100644
--- a/src/mesa/drivers/dri/intel/intel_extensions.c
+++ b/src/mesa/drivers/dri/intel/intel_extensions.c
@@ -64,7 +64,6 @@ intelInitExtensions(struct gl_context *ctx)
    ctx->Extensions.EXT_blend_equation_separate = true;
    ctx->Extensions.EXT_blend_func_separate = true;
    ctx->Extensions.EXT_blend_minmax = true;
-   ctx->Extensions.EXT_blend_subtract = true;
    ctx->Extensions.EXT_framebuffer_blit = true;
    ctx->Extensions.EXT_framebuffer_object = true;
    ctx->Extensions.EXT_framebuffer_multisample = true;
diff --git a/src/mesa/drivers/dri/intel/intel_extensions_es.c b/src/mesa/drivers/dri/intel/intel_extensions_es.c
index 4e68d7e364a..4da75a1446b 100644
--- a/src/mesa/drivers/dri/intel/intel_extensions_es.c
+++ b/src/mesa/drivers/dri/intel/intel_extensions_es.c
@@ -89,7 +89,6 @@ static const char *es2_extensions[] = {
    "GL_EXT_blend_color",
    "GL_EXT_blend_equation_separate",
    "GL_EXT_blend_minmax",
-   "GL_EXT_blend_subtract",
    "GL_NV_blend_square",
 
    /* Optional GLES2 */
diff --git a/src/mesa/drivers/dri/nouveau/nouveau_context.c b/src/mesa/drivers/dri/nouveau/nouveau_context.c
index db80e44fb3f..0f2fab3c3a4 100644
--- a/src/mesa/drivers/dri/nouveau/nouveau_context.c
+++ b/src/mesa/drivers/dri/nouveau/nouveau_context.c
@@ -120,7 +120,6 @@ nouveau_context_init(struct gl_context *ctx, struct nouveau_screen *screen,
 	ctx->Extensions.ARB_texture_mirrored_repeat = true;
 	ctx->Extensions.EXT_blend_color = true;
 	ctx->Extensions.EXT_blend_minmax = true;
-	ctx->Extensions.EXT_blend_subtract = true;
 	ctx->Extensions.EXT_fog_coord = true;
 	ctx->Extensions.EXT_framebuffer_blit = true;
 	ctx->Extensions.EXT_framebuffer_object = true;
diff --git a/src/mesa/drivers/dri/r200/r200_context.c b/src/mesa/drivers/dri/r200/r200_context.c
index dc1946fd8a0..35e1c200af9 100644
--- a/src/mesa/drivers/dri/r200/r200_context.c
+++ b/src/mesa/drivers/dri/r200/r200_context.c
@@ -365,7 +365,6 @@ GLboolean r200CreateContext( gl_api api,
    ctx->Extensions.EXT_blend_color =
       rmesa->radeon.radeonScreen->drmSupportsBlendColor;
    ctx->Extensions.EXT_blend_minmax = true;
-   ctx->Extensions.EXT_blend_subtract = true;
    ctx->Extensions.EXT_fog_coord = true;
    ctx->Extensions.EXT_packed_depth_stencil = true;
    ctx->Extensions.EXT_secondary_color = true;
diff --git a/src/mesa/drivers/dri/r300/r300_context.c b/src/mesa/drivers/dri/r300/r300_context.c
index 94a255a5fc1..74de16fec78 100644
--- a/src/mesa/drivers/dri/r300/r300_context.c
+++ b/src/mesa/drivers/dri/r300/r300_context.c
@@ -378,7 +378,6 @@ static void r300InitGLExtensions(struct gl_context *ctx)
 	ctx->Extensions.EXT_blend_equation_separate = true;
 	ctx->Extensions.EXT_blend_func_separate = true;
 	ctx->Extensions.EXT_blend_minmax = true;
-	ctx->Extensions.EXT_blend_subtract = true;
 	ctx->Extensions.EXT_fog_coord = true;
 	ctx->Extensions.EXT_gpu_program_parameters = true;
 	ctx->Extensions.EXT_point_parameters = true;
diff --git a/src/mesa/drivers/dri/r600/r600_context.c b/src/mesa/drivers/dri/r600/r600_context.c
index 42bf1bc52c9..9da8a72d57f 100644
--- a/src/mesa/drivers/dri/r600/r600_context.c
+++ b/src/mesa/drivers/dri/r600/r600_context.c
@@ -276,7 +276,6 @@ static void r600InitGLExtensions(struct gl_context *ctx)
 	ctx->Extensions.EXT_blend_equation_separate = true;
 	ctx->Extensions.EXT_blend_func_separate = true;
 	ctx->Extensions.EXT_blend_minmax = true;
-	ctx->Extensions.EXT_blend_subtract = true;
 	ctx->Extensions.EXT_packed_depth_stencil = true;
 	ctx->Extensions.EXT_fog_coord = true;
 	ctx->Extensions.EXT_gpu_program_parameters = true;
diff --git a/src/mesa/drivers/dri/radeon/radeon_context.c b/src/mesa/drivers/dri/radeon/radeon_context.c
index 2750e832fc9..7a2a5e8af26 100644
--- a/src/mesa/drivers/dri/radeon/radeon_context.c
+++ b/src/mesa/drivers/dri/radeon/radeon_context.c
@@ -318,7 +318,6 @@ r100CreateContext( gl_api api,
    ctx->Extensions.ARB_texture_env_crossbar = true;
    ctx->Extensions.ARB_texture_env_dot3 = true;
    ctx->Extensions.ARB_texture_mirrored_repeat = true;
-   ctx->Extensions.EXT_blend_subtract = true;
    ctx->Extensions.EXT_fog_coord = true;
    ctx->Extensions.EXT_packed_depth_stencil = true;
    ctx->Extensions.EXT_secondary_color = true;
diff --git a/src/mesa/drivers/dri/swrast/swrast.c b/src/mesa/drivers/dri/swrast/swrast.c
index b76cd263132..ce6fadab36d 100644
--- a/src/mesa/drivers/dri/swrast/swrast.c
+++ b/src/mesa/drivers/dri/swrast/swrast.c
@@ -598,7 +598,6 @@ static const char *es2_extensions[] = {
    "GL_EXT_blend_color",
    "GL_EXT_blend_equation_separate",
    "GL_EXT_blend_minmax",
-   "GL_EXT_blend_subtract",
 
    /* Optional GLES2 */
    "GL_ARB_framebuffer_object",
diff --git a/src/mesa/main/blend.c b/src/mesa/main/blend.c
index 98c14f56171..09acdf5c588 100644
--- a/src/mesa/main/blend.c
+++ b/src/mesa/main/blend.c
@@ -289,13 +289,12 @@ legal_blend_equation(const struct gl_context *ctx, GLenum mode)
 {
    switch (mode) {
    case GL_FUNC_ADD:
+   case GL_FUNC_SUBTRACT:
+   case GL_FUNC_REVERSE_SUBTRACT:
       return GL_TRUE;
    case GL_MIN:
    case GL_MAX:
       return ctx->Extensions.EXT_blend_minmax;
-   case GL_FUNC_SUBTRACT:
-   case GL_FUNC_REVERSE_SUBTRACT:
-      return ctx->Extensions.EXT_blend_subtract;
    default:
       return GL_FALSE;
    }
diff --git a/src/mesa/main/extensions.c b/src/mesa/main/extensions.c
index 0901b2dd63a..3df8c76380e 100644
--- a/src/mesa/main/extensions.c
+++ b/src/mesa/main/extensions.c
@@ -152,7 +152,7 @@ static const struct extension extension_table[] = {
    { "GL_EXT_blend_equation_separate",             o(EXT_blend_equation_separate),             GL,             2003 },
    { "GL_EXT_blend_func_separate",                 o(EXT_blend_func_separate),                 GL,             1999 },
    { "GL_EXT_blend_minmax",                        o(EXT_blend_minmax),                        GL | ES1 | ES2, 1995 },
-   { "GL_EXT_blend_subtract",                      o(EXT_blend_subtract),                      GL,             1995 },
+   { "GL_EXT_blend_subtract",                      o(dummy_true),                              GL,             1995 },
    { "GL_EXT_clip_volume_hint",                    o(EXT_clip_volume_hint),                    GL,             1996 },
    { "GL_EXT_compiled_vertex_array",               o(EXT_compiled_vertex_array),               GL,             1996 },
    { "GL_EXT_copy_texture",                        o(dummy_true),                              GL,             1995 },
@@ -216,7 +216,7 @@ static const struct extension extension_table[] = {
    /* OES extensions */
    { "GL_OES_blend_equation_separate",             o(EXT_blend_equation_separate),                  ES1,       2009 },
    { "GL_OES_blend_func_separate",                 o(EXT_blend_func_separate),                      ES1,       2009 },
-   { "GL_OES_blend_subtract",                      o(EXT_blend_subtract),                           ES1,       2009 },
+   { "GL_OES_blend_subtract",                      o(dummy_true),                                   ES1,       2009 },
    { "GL_OES_byte_coordinates",                    o(dummy_true),                                   ES1,       2002 },
    { "GL_OES_compressed_paletted_texture",         o(dummy_true),                                   ES1,       2003 },
    { "GL_OES_depth24",                             o(EXT_framebuffer_object),                       ES1 | ES2, 2005 },
@@ -448,7 +448,6 @@ _mesa_enable_sw_extensions(struct gl_context *ctx)
    ctx->Extensions.EXT_blend_equation_separate = GL_TRUE;
    ctx->Extensions.EXT_blend_func_separate = GL_TRUE;
    ctx->Extensions.EXT_blend_minmax = GL_TRUE;
-   ctx->Extensions.EXT_blend_subtract = GL_TRUE;
    ctx->Extensions.EXT_depth_bounds_test = GL_TRUE;
    ctx->Extensions.EXT_draw_buffers2 = GL_TRUE;
    ctx->Extensions.EXT_fog_coord = GL_TRUE;
@@ -553,7 +552,6 @@ _mesa_enable_1_4_extensions(struct gl_context *ctx)
    ctx->Extensions.EXT_blend_color = GL_TRUE;
    ctx->Extensions.EXT_blend_func_separate = GL_TRUE;
    ctx->Extensions.EXT_blend_minmax = GL_TRUE;
-   ctx->Extensions.EXT_blend_subtract = GL_TRUE;
    ctx->Extensions.EXT_fog_coord = GL_TRUE;
    ctx->Extensions.EXT_point_parameters = GL_TRUE;
    ctx->Extensions.EXT_secondary_color = GL_TRUE;
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 91cbaed88fc..63fd63d225b 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -2804,7 +2804,6 @@ struct gl_extensions
    GLboolean EXT_blend_equation_separate;
    GLboolean EXT_blend_func_separate;
    GLboolean EXT_blend_minmax;
-   GLboolean EXT_blend_subtract;
    GLboolean EXT_clip_volume_hint;
    GLboolean EXT_compiled_vertex_array;
    GLboolean EXT_depth_bounds_test;
diff --git a/src/mesa/main/version.c b/src/mesa/main/version.c
index 586bfd9454e..9c370251731 100644
--- a/src/mesa/main/version.c
+++ b/src/mesa/main/version.c
@@ -98,7 +98,6 @@ compute_version(struct gl_context *ctx)
                               ctx->Extensions.EXT_blend_color &&
                               ctx->Extensions.EXT_blend_func_separate &&
                               ctx->Extensions.EXT_blend_minmax &&
-                              ctx->Extensions.EXT_blend_subtract &&
                               ctx->Extensions.EXT_fog_coord &&
                               ctx->Extensions.EXT_point_parameters &&
                               ctx->Extensions.EXT_secondary_color);
@@ -276,7 +275,6 @@ compute_version_es2(struct gl_context *ctx)
                               ctx->Extensions.EXT_blend_color &&
                               ctx->Extensions.EXT_blend_func_separate &&
                               ctx->Extensions.EXT_blend_minmax &&
-                              ctx->Extensions.EXT_blend_subtract &&
                               ctx->Extensions.ARB_shader_objects &&
                               ctx->Extensions.ARB_vertex_shader &&
                               ctx->Extensions.ARB_fragment_shader &&
diff --git a/src/mesa/state_tracker/st_extensions.c b/src/mesa/state_tracker/st_extensions.c
index 0ffeae06738..d04a431656a 100644
--- a/src/mesa/state_tracker/st_extensions.c
+++ b/src/mesa/state_tracker/st_extensions.c
@@ -267,7 +267,6 @@ void st_init_extensions(struct st_context *st)
    ctx->Extensions.EXT_blend_color = GL_TRUE;
    ctx->Extensions.EXT_blend_func_separate = GL_TRUE;
    ctx->Extensions.EXT_blend_minmax = GL_TRUE;
-   ctx->Extensions.EXT_blend_subtract = GL_TRUE;
    ctx->Extensions.EXT_framebuffer_blit = GL_TRUE;
    ctx->Extensions.EXT_framebuffer_object = GL_TRUE;
    ctx->Extensions.EXT_framebuffer_multisample = GL_TRUE;