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 "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
