[chore] Update gin to v1.9.0 (#1553)

vendor/github.com/bytedance/sonic/internal/rt/int48.go

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2021 ByteDance Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package rt
+
+const (
+    MinInt48 = -(1 << 47)
+    MaxInt48 = +(1 << 47) - 1
+)
+
+func PackInt(v int) uint64 {
+    if u := uint64(v); v < MinInt48 || v > MaxInt48 {
+        panic("int48 out of range")
+    } else {
+        return ((u >> 63) << 47) | (u & 0x00007fffffffffff)
+    }
+}
+
+func UnpackInt(v uint64) int {
+    v &= 0x0000ffffffffffff
+    v |= (v >> 47) * (0xffff << 48)
+    return int(v)
+}