HLSL: Correct some mistakes for min16 types

- Add missing constructor ops to support float16/int16/uint16 types
- Allow half float literals
- Correct two errors of double literal parse in HLSL: extension check and
  postfix

hlsl/hlslParseHelper.cpp

@@ -8320,6 +8320,22 @@ TIntermTyped* HlslParseContext::constructBuiltIn(const TType& type, TOperator op
     // First, convert types as needed.
     //
     switch (op) {
+    case EOpConstructF16Vec2:
+    case EOpConstructF16Vec3:
+    case EOpConstructF16Vec4:
+    case EOpConstructF16Mat2x2:
+    case EOpConstructF16Mat2x3:
+    case EOpConstructF16Mat2x4:
+    case EOpConstructF16Mat3x2:
+    case EOpConstructF16Mat3x3:
+    case EOpConstructF16Mat3x4:
+    case EOpConstructF16Mat4x2:
+    case EOpConstructF16Mat4x3:
+    case EOpConstructF16Mat4x4:
+    case EOpConstructFloat16:
+        basicOp = EOpConstructFloat16;
+        break;
+
     case EOpConstructVec2:
     case EOpConstructVec3:
     case EOpConstructVec4:
@@ -8352,6 +8368,13 @@ TIntermTyped* HlslParseContext::constructBuiltIn(const TType& type, TOperator op
         basicOp = EOpConstructDouble;
         break;
 
+    case EOpConstructI16Vec2:
+    case EOpConstructI16Vec3:
+    case EOpConstructI16Vec4:
+    case EOpConstructInt16:
+        basicOp = EOpConstructInt16;
+        break;
+
     case EOpConstructIVec2:
     case EOpConstructIVec3:
     case EOpConstructIVec4:
@@ -8368,6 +8391,13 @@ TIntermTyped* HlslParseContext::constructBuiltIn(const TType& type, TOperator op
         basicOp = EOpConstructInt;
         break;
 
+    case EOpConstructU16Vec2:
+    case EOpConstructU16Vec3:
+    case EOpConstructU16Vec4:
+    case EOpConstructUint16:
+        basicOp = EOpConstructUint16;
+        break;
+
     case EOpConstructUVec2:
     case EOpConstructUVec3:
     case EOpConstructUVec4: