i965/vec4: Remove try_emit_saturate

Now that saturate is implemented natively as an instruction,
we can cut down on unneeded functionality.

Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>

src/mesa/drivers/dri/i965/brw_vec4.h

@@ -564,7 +564,6 @@ public:
 				src_reg orig_src,
 				int base_offset);
 
-   bool try_emit_sat(ir_expression *ir);
    bool try_emit_mad(ir_expression *ir);
    bool try_emit_b2f_of_compare(ir_expression *ir);
    void resolve_ud_negate(src_reg *reg);

src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp

@@ -1077,24 +1077,6 @@ vec4_visitor::visit(ir_function *ir)
    }
 }
 
-bool
-vec4_visitor::try_emit_sat(ir_expression *ir)
-{
-   ir_rvalue *sat_src = ir->as_rvalue_to_saturate();
-   if (!sat_src)
-      return false;
-
-   sat_src->accept(this);
-   src_reg src = this->result;
-
-   this->result = src_reg(this, ir->type);
-   vec4_instruction *inst;
-   inst = emit(MOV(dst_reg(this->result), src));
-   inst->saturate = true;
-
-   return true;
-}
-
 bool
 vec4_visitor::try_emit_mad(ir_expression *ir)
 {
@@ -1235,9 +1217,6 @@ vec4_visitor::visit(ir_expression *ir)
    dst_reg result_dst;
    vec4_instruction *inst;
 
-   if (try_emit_sat(ir))
-      return;
-
    if (ir->operation == ir_binop_add) {
       if (try_emit_mad(ir))
 	 return;