From 1c50d31c2613ec41d53fc784c59708e4d271f9b4 Mon Sep 17 00:00:00 2001 From: Kenneth Graunke Date: Mon, 8 Aug 2016 17:05:18 -0700 Subject: [PATCH] nir: Convert ineg(b2i(a)) to a if it's a boolean. On BDW: total instructions in shared programs: 13071119 -> 13070371 (-0.01%) instructions in affected programs: 83424 -> 82676 (-0.90%) helped: 505 HURT: 45 (all TCS, all hurt by a single instruction) total cycles in shared programs: 256601322 -> 256588932 (-0.00%) cycles in affected programs: 819410 -> 807020 (-1.51%) helped: 450 HURT: 57 total loops in shared programs: 2950 -> 2942 (-0.27%) loops in affected programs: 8 -> 0 helped: 7 HURT: 0 v2: Drop unnecessary 'a@bool' annotation (Connor, Eric). Add a comment explaining the rule (Ian). Signed-off-by: Kenneth Graunke Reviewed-by: Ian Romanick [v1] Reviewed-by: Timothy Arceri Reviewed-by: Jason Ekstrand Reviewed-by: Matt Turner --- src/compiler/nir/nir_opt_algebraic.py | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py index ff10d70..3b8836e 100644 --- a/src/compiler/nir/nir_opt_algebraic.py +++ b/src/compiler/nir/nir_opt_algebraic.py @@ -197,6 +197,8 @@ optimizations = [ (('fmul', ('b2f', a), ('b2f', b)), ('b2f', ('iand', a, b))), (('fsat', ('fadd', ('b2f', a), ('b2f', b))), ('b2f', ('ior', a, b))), (('iand', 'a@bool', 1.0), ('b2f', a)), + # True/False are ~0 and 0 in NIR. b2i of True is 1, and -1 is ~0 (True). + (('ineg', ('b2i', a)), a), (('flt', ('fneg', ('b2f', a)), 0), a), # Generated by TGSI KILL_IF. (('flt', ('fsub', 0.0, ('b2f', a)), 0), a), # Generated by TGSI KILL_IF. # Comparison with the same args. Note that these are not done for -- 2.7.4