Support implciit casted swizzled lvalue. (#3077)

* Support implciit casted swizzled lvalue.

* Fix warnings.

* Fix.

* fix comment.

* Prefer mangled linkage name for global params.

* Update tests.

---------

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

1 files changed, 10 insertions, 5 deletions

diff --git a/source/slang/slang-check-conversion.cpp b/source/slang/slang-check-conversion.cpp
index d89808c3d..09a783fb4 100644
--- a/source/slang/slang-check-conversion.cpp
+++ b/source/slang/slang-check-conversion.cpp
@@ -1360,15 +1360,20 @@ namespace Slang
         Type* toType,
         Type* fromType)
     {
-        // Can we convert at all?
-        ConversionCost conversionCost;
-        if(!canCoerce(toType, fromType, nullptr, &conversionCost))
-            return false;
+        auto conversionCost = getConversionCost(toType, fromType);
 
         // Is the conversion cheap enough to be done implicitly?
-        if(conversionCost >= kConversionCost_GeneralConversion)
+        if (conversionCost >= kConversionCost_GeneralConversion)
             return false;
 
         return true;
     }
+
+    ConversionCost SemanticsVisitor::getConversionCost(Type* toType, Type* fromType)
+    {
+        ConversionCost conversionCost = kConversionCost_Impossible;
+        if (!canCoerce(toType, fromType, nullptr, &conversionCost))
+            return kConversionCost_Impossible;
+        return conversionCost;
+    }
 }