1 /* 2 * Copyright (C) 2011 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_RUNTIME_GLOBALS_H_ 18 #define ART_RUNTIME_GLOBALS_H_ 19 20 #include <stddef.h> 21 #include <stdint.h> 22 23 namespace art { 24 25 typedef uint8_t byte; 26 typedef intptr_t word; 27 typedef uintptr_t uword; 28 29 const size_t KB = 1024; 30 const size_t MB = KB * KB; 31 const size_t GB = KB * KB * KB; 32 33 const int kWordSize = sizeof(word); 34 const int kPointerSize = sizeof(void*); 35 36 const int kBitsPerByte = 8; 37 const int kBitsPerByteLog2 = 3; 38 const int kBitsPerWord = kWordSize * kBitsPerByte; 39 const int kWordHighBitMask = 1 << (kBitsPerWord - 1); 40 41 // Required stack alignment 42 const int kStackAlignment = 16; 43 44 // Required object alignment 45 const int kObjectAlignment = 8; 46 47 // ARM instruction alignment. ARM processors require code to be 4-byte aligned, 48 // but ARM ELF requires 8.. 49 const int kArmAlignment = 8; 50 51 // MIPS instruction alignment. MIPS processors require code to be 4-byte aligned. 52 // TODO: Can this be 4? 53 const int kMipsAlignment = 8; 54 55 // X86 instruction alignment. This is the recommended alignment for maximum performance. 56 const int kX86Alignment = 16; 57 58 // System page size. We check this against sysconf(_SC_PAGE_SIZE) at runtime, but use a simple 59 // compile-time constant so the compiler can generate better code. 60 const int kPageSize = 4096; 61 62 // Whether or not this is a debug build. Useful in conditionals where NDEBUG isn't. 63 #if defined(NDEBUG) 64 const bool kIsDebugBuild = false; 65 #else 66 const bool kIsDebugBuild = true; 67 #endif 68 69 // Whether or not this is a target (vs host) build. Useful in conditionals where ART_TARGET isn't. 70 #if defined(ART_TARGET) 71 const bool kIsTargetBuild = true; 72 #else 73 const bool kIsTargetBuild = false; 74 #endif 75 76 } // namespace art 77 78 #endif // ART_RUNTIME_GLOBALS_H_ 79