Fix type truncation during SCCP. (#2163)

1 files changed, 4 insertions, 18 deletions

diff --git a/source/slang/slang-ir-sccp.cpp b/source/slang/slang-ir-sccp.cpp
index 28f262c1a..e724d0d88 100644
--- a/source/slang/slang-ir-sccp.cpp
+++ b/source/slang/slang-ir-sccp.cpp
@@ -288,7 +288,11 @@ struct SCCPContext
     {
         SLANG_SCCP_RETURN_IF_NONE_OR_ANY(v0)
         auto irConstant = as<IRConstant>(v0.value);
+
         IRInst* resultVal = nullptr;
+        if (type->getOp() == irConstant->getOp())
+            return LatticeVal::getConstant(irConstant);
+
         switch (type->getOp())
         {
         case kIROp_Int8Type:
@@ -309,24 +313,6 @@ struct SCCPContext
             case kIROp_BoolLit:
                 {
                     IRIntegerValue intVal = irConstant->value.intVal;
-                    switch (type->getOp())
-                    {
-                    case kIROp_Int8Type:
-                    case kIROp_UInt8Type:
-                        intVal = intVal & 0xFF;
-                        break;
-                    case kIROp_Int16Type:
-                    case kIROp_UInt16Type:
-                        intVal = intVal & 0xFFFF;
-                        break;
-                    case kIROp_IntType:
-                    case kIROp_UIntType:
-                    case kIROp_BoolType:
-                        intVal = intVal & 0xFFFFFFFF;
-                        break;
-                    default:
-                        break;
-                    }
                     resultVal = getBuilder()->getIntValue(type, (IRIntegerValue)intVal);
                 }
                 break;