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 static constexpr int32_t Sk64_pin_to_s32(int64_t x) { 12 return x < SK_MinS32 ? SK_MinS32 : (x > SK_MaxS32 ? SK_MaxS32 : x); 13 } 14 15 static constexpr int32_t Sk32_sat_add(int32_t a, int32_t b) { 16 return Sk64_pin_to_s32((int64_t)a + (int64_t)b); 17 } 18 19 static constexpr int32_t Sk32_sat_sub(int32_t a, int32_t b) { 20 return Sk64_pin_to_s32((int64_t)a - (int64_t)b); 21 } 22 23 // To avoid UBSAN complaints about 2's compliment overflows 24 // 25 static constexpr int32_t Sk32_can_overflow_add(int32_t a, int32_t b) { 26 return (int32_t)((uint32_t)a + (uint32_t)b); 27 } 28 static constexpr int32_t Sk32_can_overflow_sub(int32_t a, int32_t b) { 29 return (int32_t)((uint32_t)a - (uint32_t)b); 30 } 31 32 #endif 33
