| // Protocol Buffers - Google's data interchange format |
| // Copyright 2023 Google LLC. All rights reserved. |
| // https://developers.google.com/protocol-buffers/ |
| /// |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file or at |
| // https://developers.google.com/open-source/licenses/bsd |
| |
| #ifndef UPB_BASE_INTERNAL_LOG2_H_ |
| #define UPB_BASE_INTERNAL_LOG2_H_ |
| |
| // Must be last. |
| #include "upb/port/def.inc" |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| UPB_INLINE int upb_Log2Ceiling(int x) { |
| if (x <= 1) return 0; |
| #ifdef __GNUC__ |
| return 32 - __builtin_clz(x - 1); |
| #else |
| int lg2 = 0; |
| while ((1 << lg2) < x) lg2++; |
| return lg2; |
| #endif |
| } |
| |
| UPB_INLINE int upb_RoundUpToPowerOfTwo(int x) { |
| return 1 << upb_Log2Ceiling(x); |
| } |
| |
| #ifdef __cplusplus |
| } /* extern "C" */ |
| #endif |
| |
| #include "upb/port/undef.inc" |
| |
| #endif /* UPB_BASE_INTERNAL_LOG2_H_ */ |
