shader/shift: Implement SHR wrapped and clamped variants

Nvidia defaults to wrapped shifts, but this is undefined behaviour on
OpenGL's spec. Explicitly mask/clamp according to what the guest shader
requires.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/video_core/engines/shader_bytecode.h b/src/video_core/engines/shader_bytecode.h
index c3678b9ea..bd8c1ada0 100644
--- a/src/video_core/engines/shader_bytecode.h
+++ b/src/video_core/engines/shader_bytecode.h
@@ -675,6 +675,10 @@ union Instruction {
     } shift;
 
     union {
+        BitField<39, 1, u64> wrap;
+    } shr;
+
+    union {
         BitField<39, 5, u64> shift_amount;
         BitField<48, 1, u64> negate_b;
         BitField<49, 1, u64> negate_a;