From: Thomas Helland <thomashellan...@gmail.com> Let's cut the needless A && B here.
v1 -> v2: Correct the comments, return A instead of A && B v2 -> v3: Rebase on top of this series Signed-off-by: Thomas Helland <thomashelland90 at gmail.com> --- This was originally posted here: http://lists.freedesktop.org/archives/mesa-dev/2014-July/063129.html v2 of the patch got no responses, so I'm reposting it here. This used to give some effect on a clean shader-db with some extra shaders from TF2 and portal; helped: shaders/tf2/2042.shader_test fs16: 23 -> 21 (-8.70%) helped: shaders/tf2/2042.shader_test fs8: 23 -> 21 (-8.70%) helped: shaders/tf2/4624.shader_test fs16: 21 -> 19 (-9.52%) helped: shaders/tf2/4624.shader_test fs8: 21 -> 19 (-9.52%) helped: shaders/tf2/763.shader_test fs16: 23 -> 21 (-8.70%) helped: shaders/tf2/763.shader_test fs8: 23 -> 21 (-8.70%) HURT: shaders/orbital_explorer.shader_test vs: 1049 -> 1052 (0.29%) total instructions in shared programs: 758979 -> 758970 (-0.00%) instructions in affected programs: 1183 -> 1174 (-0.76%) GAINED: 0 LOST: 0 However, current master gets this optimized, probably in i965 backend; the previously affected shaders now get the same amount of instructions with master as they did with this patch, and this patch has no effect. It does, however, cause 5 extra crashes in a piglit-quick run. I have not investigated this any further. --- src/glsl/opt_algebraic.cpp | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/src/glsl/opt_algebraic.cpp b/src/glsl/opt_algebraic.cpp index c673495..4008fe7 100644 --- a/src/glsl/opt_algebraic.cpp +++ b/src/glsl/opt_algebraic.cpp @@ -647,7 +647,17 @@ ir_algebraic_visitor::handle_expression(ir_expression *ir) data.b[i] = true; return new(mem_ctx) ir_constant(ir->type, &data); - } + } else if (op_expr[0] && op_expr[0]->operation == ir_binop_logic_and && + (op_expr[0]->operands[0]->equals(op_expr[1]) || + op_expr[0]->operands[1]->equals(op_expr[1]))) { + /* (A && B) || A == A or (B && A) || A == A */ + return ir->operands[1]; + } else if (op_expr[1] && op_expr[1]->operation == ir_binop_logic_and && + (op_expr[1]->operands[0]->equals(op_expr[0]) || + op_expr[1]->operands[1]->equals(op_expr[0]))) { + /* A || (A && B) == A or A || (B && A) == A */ + return ir->operands[0]; + } break; case ir_binop_pow: -- 2.0.3 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
