From: Chris Forbes <chrisf@ijw.co.nz>
Date: Tue, 23 Jul 2013 19:21:22 +0000 (+1200)
Subject: i965/vs: Fix flaky texture swizzling
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=124f567f1d575eaea98a6ae1d0a4687b8fb5bba2;p=mesa.git

i965/vs: Fix flaky texture swizzling

If any component used the ZERO or ONE swizzle, its corresponding member
in the `swizzle` array would never be initialized. We *mostly* got away
with this, except when that memory happened to contain a value that
clobbered another channel when combined using BRW_SWIZZLE4().

NOTE: This is a candidate for stable branches.

Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
---

diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index 3eb43a87750..1d86b33e8e8 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -2506,7 +2506,7 @@ vec4_visitor::swizzle_result(ir_texture *ir, src_reg orig_val, int sampler)
    }
 
    int zero_mask = 0, one_mask = 0, copy_mask = 0;
-   int swizzle[4];
+   int swizzle[4] = {0};
 
    for (int i = 0; i < 4; i++) {
       switch (GET_SWZ(s, i)) {