Mesa (10.4): st/nine: Fix setting of the shift modifier in nine_shader

[Emil Velikov]

Module: Mesa
Branch: 10.4
Commit: 72a802a9c28671f34e5407de0069705d8596d515
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=72a802a9c28671f34e5407de0069705d8596d515

Author: Axel Davy <axel.davy at ens.fr>
Date:   Tue Nov 25 00:38:10 2014 +0100

st/nine: Fix setting of the shift modifier in nine_shader

It is an sint_4, but it was stored in a uint_8...
The code using it was acting as if it was signed.

Problem found thanks to Coverity

Cc: "10.4" <mesa-stable at lists.freedesktop.org>
Tested-by: David Heidelberg <david at ixit.cz>
Reviewed-by: Ilia Mirkin <imirkin at alum.mit.edu>
Signed-off-by: Axel Davy <axel.davy at ens.fr>
(cherry picked from commit d52328fc398aae4c3582172516b0ad98f0677b58)

---

 src/gallium/state_trackers/nine/nine_shader.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/gallium/state_trackers/nine/nine_shader.c b/src/gallium/state_trackers/nine/nine_shader.c
index c5b1ccb..77aa82e 100644
--- a/src/gallium/state_trackers/nine/nine_shader.c
+++ b/src/gallium/state_trackers/nine/nine_shader.c
@@ -239,7 +239,7 @@ struct sm1_dst_param
     BYTE file;
     BYTE mask;
     BYTE mod;
-    BYTE shift; /* sint4 */
+    int8_t shift; /* sint4 */
     BYTE type;
 };
 
@@ -2535,6 +2535,7 @@ sm1_parse_get_param(struct shader_translator *tx, DWORD *reg, DWORD *rel)
 static void
 sm1_parse_dst_param(struct sm1_dst_param *dst, DWORD tok)
 {
+    uint8_t shift;
     dst->file =
         (tok & D3DSP_REGTYPE_MASK)  >> D3DSP_REGTYPE_SHIFT |
         (tok & D3DSP_REGTYPE_MASK2) >> D3DSP_REGTYPE_SHIFT2;
@@ -2543,7 +2544,8 @@ sm1_parse_dst_param(struct sm1_dst_param *dst, DWORD tok)
     dst->rel = NULL;
     dst->mask = (tok & NINED3DSP_WRITEMASK_MASK) >> NINED3DSP_WRITEMASK_SHIFT;
     dst->mod = (tok & D3DSP_DSTMOD_MASK) >> D3DSP_DSTMOD_SHIFT;
-    dst->shift = (tok & D3DSP_DSTSHIFT_MASK) >> D3DSP_DSTSHIFT_SHIFT;
+    shift = (tok & D3DSP_DSTSHIFT_MASK) >> D3DSP_DSTSHIFT_SHIFT;
+    dst->shift = (shift & 0x8) ? -(shift & 0x7) : shift & 0x7;
 }
 
 static void