From: Eric Anholt <eric@anholt.net>
Date: Mon, 7 Nov 2016 18:34:01 +0000 (-0800)
Subject: nir: Avoid an extra NIR op in integer divide lowering.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=80786a67cf64f9d3ae21b42ab7690255105a66db;p=mesa.git

nir: Avoid an extra NIR op in integer divide lowering.

NIR bools are ~0 for true, so ((unsigned)a >> 31) != 0 -> ((int)a >> 31).

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
---

diff --git a/src/compiler/nir/nir_lower_idiv.c b/src/compiler/nir/nir_lower_idiv.c
index b1e7aeb03c8..6726b718aaa 100644
--- a/src/compiler/nir/nir_lower_idiv.c
+++ b/src/compiler/nir/nir_lower_idiv.c
@@ -101,8 +101,7 @@ convert_instr(nir_builder *bld, nir_alu_instr *alu)
    if (is_signed)  {
       /* fix the sign: */
       r = nir_ixor(bld, numer, denom);
-      r = nir_ushr(bld, r, nir_imm_int(bld, 31));
-      r = nir_i2b(bld, r);
+      r = nir_ishr(bld, r, nir_imm_int(bld, 31));
       b = nir_ineg(bld, q);
       q = nir_bcsel(bld, r, b, q);
    }