From: José Fonseca <jfonseca@vmware.com>
Date: Wed, 20 Jul 2011 21:41:17 +0000 (-0700)
Subject: gallivm: Increase lp_build_rsqrt() precision.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=47d6d44a231b811f1bba05478a6bbfb1e3fdb27b;p=mesa.git

gallivm: Increase lp_build_rsqrt() precision.

Add an iteration step, which makes rqsqrt precision go from 12bits to
24, and fixes RSQ/NRM test case of PSPrecision/VSPrevision DCTs.

There are no uses of this function outside shader translation.
---

diff --git a/src/gallium/auxiliary/gallivm/lp_bld_arit.c b/src/gallium/auxiliary/gallivm/lp_bld_arit.c
index 06e5debe4a3..fce4685cc2d 100644
--- a/src/gallium/auxiliary/gallivm/lp_bld_arit.c
+++ b/src/gallium/auxiliary/gallivm/lp_bld_arit.c
@@ -1645,7 +1645,7 @@ lp_build_rsqrt(struct lp_build_context *bld,
    assert(type.floating);
 
    if (util_cpu_caps.has_sse && type.width == 32 && type.length == 4) {
-      const unsigned num_iterations = 0;
+      const unsigned num_iterations = 1;
       LLVMValueRef res;
       unsigned i;