i965: Emit MOVs for neg/abs.

Necessary to avoid combining a bitcast and a modifier into a single
operation. Otherwise if safe, the MOV should be removed by
copy-propagation or register coalescing.

With this and the next patch, there are only four changes in shader-db:
all a single extra instruction. The code does something like
   mov a.w, -b.x
and copy propagation doesn't work because it only handles no-op
swizzles. Seems acceptable, given the known limitation of our copy
propagation.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Paul Berry <stereoytpe441@gmail.com>
This commit is contained in:
Matt Turner 2013-08-08 13:50:01 -07:00
parent 079bdba05f
commit 0ae9ca12a8
2 changed files with 4 additions and 4 deletions

View File

@ -361,12 +361,12 @@ fs_visitor::visit(ir_expression *ir)
break;
case ir_unop_neg:
op[0].negate = !op[0].negate;
this->result = op[0];
emit(MOV(this->result, op[0]));
break;
case ir_unop_abs:
op[0].abs = true;
op[0].negate = false;
this->result = op[0];
emit(MOV(this->result, op[0]));
break;
case ir_unop_sign:
temp = fs_reg(this, ir->type);

View File

@ -1365,12 +1365,12 @@ vec4_visitor::visit(ir_expression *ir)
break;
case ir_unop_neg:
op[0].negate = !op[0].negate;
this->result = op[0];
emit(MOV(result_dst, op[0]));
break;
case ir_unop_abs:
op[0].abs = true;
op[0].negate = false;
this->result = op[0];
emit(MOV(result_dst, op[0]));
break;
case ir_unop_sign: