Bug fixes for the direct spirv backend. (#3474)

* Fix GLSL legalization bug that leads to crash.

* Update diagnostic id to avoid conflict.

* Fix std140 layout logic.

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Co-authored-by: Yong He <yhe@nvidia.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/source/slang/slang-ir-layout.cpp b/source/slang/slang-ir-layout.cpp
index 79012e7ba..a6684c7b1 100644
--- a/source/slang/slang-ir-layout.cpp
+++ b/source/slang/slang-ir-layout.cpp
@@ -461,9 +461,10 @@ struct Std140LayoutRules : IRTypeLayoutRules
     }
     virtual IRSizeAndAlignment getVectorSizeAndAlignment(IRSizeAndAlignment element, IRIntegerValue count)
     {
+        IRIntegerValue alignmentCount = count;
         if (count == 3)
-            count = 4;
-        return IRSizeAndAlignment((int)(element.size * count), (int)(element.size * count));
+            alignmentCount = 4;
+        return IRSizeAndAlignment((int)(element.size * count), (int)(element.size * alignmentCount));
     }
 };