[Mesa-dev] [PATCH 2/2] i965/vec4: Don't reswizzle hardware registers

[Jason Ekstrand]

Cc: "11.0 10.6" <mesa-stable at lists.freedesktop.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91719
---
 src/mesa/drivers/dri/i965/brw_vec4.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp b/src/mesa/drivers/dri/i965/brw_vec4.cpp
index 78ee8fe..01c1259 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp
@@ -953,6 +953,13 @@ vec4_instruction::can_reswizzle(int dst_writemask,
    if (mlen > 0)
       return false;
 
+   /* We can't use swizzles on the accumulator and that's really the only
+    * HW_REG we would care to reswizzle so just dissalow them all.
+    */
+   for (int i = 0; i < 3; i++)
+      if (src[i].file == HW_REG)
+         return false;
+
    return true;
 }
 
-- 
2.5.0.400.gff86faf