6 files changed, 54 insertions, 6 deletions
diff --git a/source/slang/emit.cpp b/source/slang/emit.cpp
index 84d8f113e..dccb12f53 100644
--- a/source/slang/emit.cpp
+++ b/source/slang/emit.cpp
@@ -4743,9 +4743,15 @@ emitDeclImpl(decl, nullptr);
             switch(peek())
             {
             case 'T':
+            case 'C':
                 get();
                 break;
 
+            case 'v':
+                get();
+                readType();
+                break;
+
             default:
                 SLANG_UNEXPECTED("bad name mangling");
                 break;
@@ -4862,7 +4868,9 @@ emitDeclImpl(decl, nullptr);
         UInt readParamCount()
         {
             expect("p");
-            return readCount();
+            UInt count = readCount();
+            expect("p");
+            return count;
         }
     };
 
@@ -5438,6 +5446,9 @@ emitDeclImpl(decl, nullptr);
                 SLANG_UNEXPECTED("terminator inst");
                 return;
 
+            case kIROp_unreachable:
+                return;
+
             case kIROp_ReturnVal:
             case kIROp_ReturnVoid:
             case kIROp_discard:
diff --git a/source/slang/ir-inst-defs.h b/source/slang/ir-inst-defs.h
index dbdb697a4..ffad04467 100644
--- a/source/slang/ir-inst-defs.h
+++ b/source/slang/ir-inst-defs.h
@@ -184,6 +184,7 @@ INST(loopTest, loopTest, 3, 0)
 INST(switch, switch, 3, 0)
 
 INST(discard, discard, 0, 0)
+INST(unreachable, unreachable, 0, 0)
 
 INST(Add, add, 2, 0)
 INST(Sub, sub, 2, 0)
diff --git a/source/slang/ir-insts.h b/source/slang/ir-insts.h
index b4335656e..52acf6576 100644
--- a/source/slang/ir-insts.h
+++ b/source/slang/ir-insts.h
@@ -138,6 +138,13 @@ struct IRReturnVoid : IRReturn
 struct IRDiscard : IRTerminatorInst
 {};
 
+// Signals that this point in the code should be unreachable.
+// We can/should emit a dataflow error if we can ever determine
+// that a block ending in one of these can actually be
+// executed.
+struct IRUnreachable : IRTerminatorInst
+{};
+
 struct IRBlock;
 
 struct IRUnconditionalBranch : IRTerminatorInst
@@ -487,6 +494,8 @@ struct IRBuilder
 
     IRInst* emitDiscard();
 
+    IRInst* emitUnreachable();
+
     IRInst* emitBranch(
         IRBlock*    block);
 
diff --git a/source/slang/ir.cpp b/source/slang/ir.cpp
index 313fd258b..92bcb6707 100644
--- a/source/slang/ir.cpp
+++ b/source/slang/ir.cpp
@@ -168,6 +168,7 @@ namespace Slang
         case kIROp_loopTest:
         case kIROp_discard:
         case kIROp_switch:
+        case kIROp_unreachable:
             return true;
         }
     }
@@ -1152,6 +1153,16 @@ namespace Slang
         return inst;
     }
 
+    IRInst* IRBuilder::emitUnreachable()
+    {
+        auto inst = createInst<IRUnreachable>(
+            this,
+            kIROp_unreachable,
+            nullptr);
+        addInst(inst);
+        return inst;
+    }
+
     IRInst* IRBuilder::emitDiscard()
     {
         auto inst = createInst<IRDiscard>(
@@ -3457,6 +3468,14 @@ namespace Slang
         return clonedFunc;
     }
 
+    IRFunc* cloneSimpleFuncWithoutRegistering(IRSpecContextBase* context, IRFunc* originalFunc)
+    {
+        auto clonedFunc = context->builder->createFunc();
+        cloneFunctionCommon(context, clonedFunc, originalFunc);
+        return clonedFunc;
+    }
+
+
     IRFunc* cloneSimpleFunc(IRSpecContextBase* context, IRFunc* originalFunc)
     {
         auto clonedFunc = context->builder->createFunc();
@@ -4017,7 +4036,7 @@ namespace Slang
 
         // TODO: other initialization is needed here...
 
-        auto specFunc = cloneSimpleFunc(&context, genericFunc);
+        auto specFunc = cloneSimpleFuncWithoutRegistering(&context, genericFunc);
 
         // Set up the clone to recognize that it is no longer generic
         specFunc->mangledName = specMangledName;
diff --git a/source/slang/lower-to-ir.cpp b/source/slang/lower-to-ir.cpp
index f642b316e..827504122 100644
--- a/source/slang/lower-to-ir.cpp
+++ b/source/slang/lower-to-ir.cpp
@@ -3242,8 +3242,7 @@ struct DeclLoweringVisitor : DeclVisitor<DeclLoweringVisitor, LoweredValInfo>
                     // this by putting an `unreachable` terminator here,
                     // and then emit a dataflow error if this block
                     // can't be eliminated.
-                    SLANG_UNEXPECTED("Needed a return here");
-                    UNREACHABLE(subContext->irBuilder->emitReturn());
+                    subContext->irBuilder->emitUnreachable();
                 }
             }
         }
diff --git a/source/slang/mangle.cpp b/source/slang/mangle.cpp
index 38c2b29a8..68fa7f31b 100644
--- a/source/slang/mangle.cpp
+++ b/source/slang/mangle.cpp
@@ -164,6 +164,13 @@ namespace Slang
             // parameter are they at the specified depth).
             emitName(context, genericParamIntVal->declRef.GetName());
         }
+        else if( auto constantIntVal = dynamic_cast<ConstantIntVal*>(val) )
+        {
+            // TODO: need to figure out what prefix/suffix is needed
+            // to allow demangling later.
+            emitRaw(context, "k");
+            emit(context, (UInt) constantIntVal->value);
+        }
         else
         {
             SLANG_UNEXPECTED("unimplemented case in mangling");
@@ -277,11 +284,13 @@ namespace Slang
         //
         if( auto callableDeclRef = declRef.As<CallableDecl>())
         {
-            emitRaw(context, "p");
-
             auto parameters = GetParameters(callableDeclRef);
             UInt parameterCount = parameters.Count();
+
+            emitRaw(context, "p");
             emit(context, parameterCount);
+            emitRaw(context, "p");
+
             for(auto paramDeclRef : parameters)
             {
                 emitType(context, GetType(paramDeclRef));