[Mesa-dev] [PATCH 4/4] nir: Rely on the fact that bcsel takes a well formed boolean.

[Kenneth Graunke]

According to Connor, it's safe to assume that the first operand of
bcsel, as well as the operand of b2f and b2i, must be well formed
booleans.

https://lists.freedesktop.org/archives/mesa-dev/2016-August/125658.html

With the previous improvements to a at bool handling, this now has no
change in shader-db instruction counts on Broadwell.

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/compiler/nir/nir_opt_algebraic.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py
index 0f0896b..ceb8730 100644
--- a/src/compiler/nir/nir_opt_algebraic.py
+++ b/src/compiler/nir/nir_opt_algebraic.py
@@ -144,7 +144,7 @@ optimizations = [
    (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
    (('bcsel', ('flt', b, a), b, a), ('fmin', a, b)),
    (('bcsel', ('flt', a, b), b, a), ('fmax', a, b)),
-   (('bcsel', ('inot', 'a at bool'), b, c), ('bcsel', a, c, b)),
+   (('bcsel', ('inot', a), b, c), ('bcsel', a, c, b)),
    (('bcsel', a, ('bcsel', a, b, c), d), ('bcsel', a, b, d)),
    (('bcsel', a, True, 'b at bool'), ('ior', a, b)),
    (('fmin', a, a), a),
@@ -248,8 +248,8 @@ optimizations = [
    (('ine', 'a at bool', True), ('inot', a)),
    (('ine', 'a at bool', False), a),
    (('ieq', 'a at bool', False), ('inot', 'a')),
-   (('bcsel', a, True, False), ('ine', a, 0)),
-   (('bcsel', a, False, True), ('ieq', a, 0)),
+   (('bcsel', a, True, False), a),
+   (('bcsel', a, False, True), ('inot', a)),
    (('bcsel', True, b, c), b),
    (('bcsel', False, b, c), c),
    # The result of this should be hit by constant propagation and, in the
-- 
2.9.0