Fixed naming conflicts in heterogeneous-hello-world (#2114)

* Fixed naming conflicts in heterogeneous-hello-world

Added 3 new modifiers (`__unmangled`, `__exportDirectly`, `__externLib`)

`__unmangled`  causes mangleName() to return the normal name of the decl.

`__exportDirectly` changes parent decl name concatenation behavior to use
"::" instead of "." (for Name Hint) and emits the name hint when it exists,
otherwise it emits the mangled name.

`__externLib` stops Slang from emitting the corresponding struct.

Also made necessary changes to heterogeneous-hello-world so that this new
functionality is shown off.

* Undo unintentional formatting changes

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

1 files changed, 10 insertions, 2 deletions

diff --git a/source/slang/slang-mangle.cpp b/source/slang/slang-mangle.cpp
index b0568994f..acb561531 100644
--- a/source/slang/slang-mangle.cpp
+++ b/source/slang/slang-mangle.cpp
@@ -453,12 +453,20 @@ namespace Slang
         // forward to something else? E.g., what if we
         // are asked to mangle the name of a `typedef`?
 
+        auto decl = declRef.getDecl();
+
+        // Handle `__unmangled` modifier by simply emitting
+        // the given name.
+        if (decl->hasModifier<UnmangledModifier>())
+        {
+            emit(context, decl->getName()->text);
+            return;
+        }
+
         // We will start with a unique prefix to avoid
         // clashes with user-defined symbols:
         emitRaw(context, "_S");
 
-        auto decl = declRef.getDecl();
-
         // Next we will add a bit of info to register
         // the *kind* of declaration we are dealing with.
         //