ir_to_mesa: Remove sat to clamp lowering pass

Fixes an infinite loop in swrast where the lowering pass unpacks saturate into
clamp but the opt_algebraic pass tries to do the opposite.

v3 (Ian):
This is a revert of commit cfa8c1cb "ir_to_mesa: lower ir_unop_saturate" on
the ir_to_mesa.cpp portion. prog_execute.c can handle saturates in vertex
shaders, so classic swrast shouldn't need this lowering pass.

Cc: "10.4" <mesa-stable@lists.freedesktop.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=83463
Reviewed-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>

diff --git a/src/mesa/program/ir_to_mesa.cpp b/src/mesa/program/ir_to_mesa.cpp
index 5cd9058..68e2597 100644 (file)
--- a/src/mesa/program/ir_to_mesa.cpp
+++ b/src/mesa/program/ir_to_mesa.cpp
@@ -2946,9 +2946,7 @@ _mesa_ir_link_shader(struct gl_context *ctx, struct gl_shader_program *prog)
         GLenum target = _mesa_shader_stage_to_program(prog->_LinkedShaders[i]->Stage);
         lower_instructions(ir, (MOD_TO_FRACT | DIV_TO_MUL_RCP | EXP_TO_EXP2
                                 | LOG_TO_LOG2 | INT_DIV_TO_MUL_RCP
-                                | ((options->EmitNoPow) ? POW_TO_EXP2 : 0)
-                                | ((target == GL_VERTEX_PROGRAM_ARB) ? SAT_TO_CLAMP
-                                    : 0)));
+                                | ((options->EmitNoPow) ? POW_TO_EXP2 : 0)));
 
         progress = do_lower_jumps(ir, true, true, options->EmitNoMainReturn, options->EmitNoCont, options->EmitNoLoops) || progress;