| 1 | /* | 
|---|---|
| 2 | * Copyright 2018 Google Inc. | 
| 3 | * | 
| 4 | * Use of this source code is governed by a BSD-style license that can be | 
| 5 | * found in the LICENSE file. | 
| 6 | */ | 
| 7 | |
| 8 | #ifndef SkSafe32_DEFINED | 
| 9 | #define SkSafe32_DEFINED | 
| 10 | |
| 11 | #include "include/core/SkTypes.h" | 
| 12 | |
| 13 | static constexpr int32_t Sk64_pin_to_s32(int64_t x) { | 
| 14 | return x < SK_MinS32 ? SK_MinS32 : (x > SK_MaxS32 ? SK_MaxS32 : (int32_t)x); | 
| 15 | } | 
| 16 | |
| 17 | static constexpr int32_t Sk32_sat_add(int32_t a, int32_t b) { | 
| 18 | return Sk64_pin_to_s32((int64_t)a + (int64_t)b); | 
| 19 | } | 
| 20 | |
| 21 | static constexpr int32_t Sk32_sat_sub(int32_t a, int32_t b) { | 
| 22 | return Sk64_pin_to_s32((int64_t)a - (int64_t)b); | 
| 23 | } | 
| 24 | |
| 25 | // To avoid UBSAN complaints about 2's compliment overflows | 
| 26 | // | 
| 27 | static constexpr int32_t Sk32_can_overflow_add(int32_t a, int32_t b) { | 
| 28 | return (int32_t)((uint32_t)a + (uint32_t)b); | 
| 29 | } | 
| 30 | static constexpr int32_t Sk32_can_overflow_sub(int32_t a, int32_t b) { | 
| 31 | return (int32_t)((uint32_t)a - (uint32_t)b); | 
| 32 | } | 
| 33 | |
| 34 | #endif | 
| 35 | 
