Fix enum array indexing by adding implicit conversion support (#7815)

* Initial plan

* Fix enum array indexing by adding implicit conversion support

Co-authored-by: csyonghe <2652293+csyonghe@users.noreply.github.com>

* Update enum array indexing test to support GPU backends

Co-authored-by: csyonghe <2652293+csyonghe@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: csyonghe <2652293+csyonghe@users.noreply.github.com>

1 files changed, 3 insertions, 6 deletions

diff --git a/source/slang/slang-check-expr.cpp b/source/slang/slang-check-expr.cpp
index 41c3bd510..2891c316f 100644
--- a/source/slang/slang-check-expr.cpp
+++ b/source/slang/slang-check-expr.cpp
@@ -2490,13 +2490,10 @@ Expr* SemanticsVisitor::CheckSimpleSubscriptExpr(IndexExpr* subscriptExpr, Type*
     {
         expr = CheckExpr(expr);
     }
-    auto indexExpr = subscriptExpr->indexExprs[0];
+    auto& indexExpr = subscriptExpr->indexExprs[0];
 
-    if (!isScalarIntegerType(indexExpr->type.type))
-    {
-        getSink()->diagnose(indexExpr, Diagnostics::subscriptIndexNonInteger);
-        return CreateErrorExpr(subscriptExpr);
-    }
+    auto intTargetType = getMatchingIntType(indexExpr->type.type);
+    indexExpr = coerce(CoercionSite::Argument, intTargetType, indexExpr, getSink());
 
     subscriptExpr->type = QualType(elementType);