stack_checks.h revision ab9a0dbf3b63d517da5278b8298e6cd316e09f68
1/* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#ifndef ART_COMPILER_UTILS_STACK_CHECKS_H_ 18#define ART_COMPILER_UTILS_STACK_CHECKS_H_ 19 20#include "instruction_set.h" 21 22namespace art { 23 24// Size of a frame that we definitely consider large. Anything larger than this should 25// definitely get a stack overflow check. 26static constexpr size_t kLargeFrameSize = 2 * KB; 27 28// Size of a frame that should be small. Anything leaf method smaller than this should run 29// without a stack overflow check. 30// The constant is from experience with frameworks code. 31static constexpr size_t kSmallFrameSize = 1 * KB; 32 33// Determine whether a frame is small or large, used in the decision on whether to elide a 34// stack overflow check on method entry. 35// 36// A frame is considered large when it's either above kLargeFrameSize, or a quarter of the 37// overflow-usable stack space. 38static inline bool IsLargeFrame(size_t size, InstructionSet isa) { 39 return size >= kLargeFrameSize || size >= GetStackOverflowReservedBytes(isa) / 4; 40} 41 42} // namespace art 43 44#endif // ART_COMPILER_UTILS_STACK_CHECKS_H_ 45