Support SM6.6 keyword "WaveSize" (#3871)

Resolves an issue #3385

Shader Model 6.6 added a new keyowrd, "WaveSize". See the following link
for more details:
  https://microsoft.github.io/DirectX-Specs/d3d/HLSL_SM_6_6_WaveSize.html

Co-authored-by: Yong He <yonghe@outlook.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/source/slang/slang-lower-to-ir.cpp b/source/slang/slang-lower-to-ir.cpp
index 4372d6e7c..1e324b4a4 100644
--- a/source/slang/slang-lower-to-ir.cpp
+++ b/source/slang/slang-lower-to-ir.cpp
@@ -9625,6 +9625,13 @@ struct DeclLoweringVisitor : DeclVisitor<DeclLoweringVisitor, LoweredValInfo>
                     getSimpleVal(context, lowerVal(context, numThreadsAttr->z))
                 );
             }
+            else if (auto waveSizeAttr = as<WaveSizeAttribute>(modifier))
+            {
+                getBuilder()->addWaveSizeDecoration(
+                    irFunc,
+                    getSimpleVal(context, lowerVal(context, waveSizeAttr->numLanes))
+                );
+            }
             else if (as<ReadNoneAttribute>(modifier))
             {
                 getBuilder()->addSimpleDecoration<IRReadNoneDecoration>(irFunc);