core: Change bitshift operators to accept int32/uint32 for RHS operand

nac3core/src/codegen/expr.rs

@@ -298,16 +298,21 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
             (Operator::BitOr, _) => self.builder.build_or(lhs, rhs, "or").into(),
             (Operator::BitXor, _) => self.builder.build_xor(lhs, rhs, "xor").into(),
             (Operator::BitAnd, _) => self.builder.build_and(lhs, rhs, "and").into(),
+
+            // Sign-ness of bitshift operators are always determined by the left operand
             (Operator::LShift, signed) | (Operator::RShift, signed) => {
+                // RHS operand is always 32 bits
+                assert_eq!(rhs.get_type().get_bit_width(), 32);
+
                 let common_type = lhs.get_type();
-                let rhs = if common_type.get_bit_width() > rhs.get_type().get_bit_width() {
+                let rhs = if common_type.get_bit_width() > 32 {
                     if signed {
                         self.builder.build_int_s_extend(rhs, common_type, "")
                     } else {
                         self.builder.build_int_z_extend(rhs, common_type, "")
                     }
                 } else {
-                    self.builder.build_int_truncate_or_bit_cast(rhs, common_type, "")
+                    rhs
                 };
 
                 let rhs_gez = self.builder.build_int_compare(IntPredicate::SGE, rhs, common_type.const_zero(), "");
@@ -325,7 +330,8 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                     Operator::RShift => self.builder.build_right_shift(lhs, rhs, signed, "rshift").into(),
                     _ => unreachable!()
                 }
-            },
+            }
+
             (Operator::FloorDiv, true) => self.builder.build_int_signed_div(lhs, rhs, "floordiv").into(),
             (Operator::FloorDiv, false) => self.builder.build_int_unsigned_div(lhs, rhs, "floordiv").into(),
             (Operator::Pow, s) => integer_power(generator, self, lhs, rhs, s).into(),