Allow CPP/CUDA/Metal to lower/legalize buffer-elements to support column_major/row_major. (#4653)

* Allow CPP/CUDA/Metal to legalize their buffer-elements.

Fixes: #4537

Changes:
1. Matrix inputs require legalization (pack/unpack) to ensure consistent row_major/column_major throughout entire shader, the following enabled legalization pass fixes this.
2. Added missing CUDA intrinsic so CUDA can run more tests.
3. Added a memory packing test since this still fails for cpp/cuda/metal (due to having no memory packing enforcement).

* change memory packing tests to run for targets without packing

---------

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

1 files changed, 1 insertions, 9 deletions

diff --git a/source/slang/slang-emit.cpp b/source/slang/slang-emit.cpp
index 679d8ce88..678b4137a 100644
--- a/source/slang/slang-emit.cpp
+++ b/source/slang/slang-emit.cpp
@@ -1267,15 +1267,7 @@ Result linkAndOptimizeIR(
     if (requiredLoweringPassSet.meshOutput)
         legalizeMeshOutputTypes(irModule);
 
-    if (options.shouldLegalizeExistentialAndResourceTypes)
-    {
-        if (!isMetalTarget(targetRequest))
-        {
-            // We need to lower any types used in a buffer resource (e.g. ContantBuffer or StructuredBuffer) into
-            // a simple storage type that has target independent layout based on the kind of buffer resource.
-            lowerBufferElementTypeToStorageType(targetProgram, irModule);
-        }
-    }
+    lowerBufferElementTypeToStorageType(targetProgram, irModule);
 
     // Rewrite functions that return arrays to return them via `out` parameter,
     // since our target languages doesn't allow returning arrays.