Disable loading bytecode with an extra header (BOM or #!).
[luajit-2.0.git] / src / lj_def.h
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1 /*
2 ** LuaJIT common internal definitions.
3 ** Copyright (C) 2005-2012 Mike Pall. See Copyright Notice in luajit.h
4 */
6 #ifndef _LJ_DEF_H
7 #define _LJ_DEF_H
9 #include "lua.h"
11 #if defined(_MSC_VER)
12 /* MSVC is stuck in the last century and doesn't have C99's stdint.h. */
13 typedef __int8 int8_t;
14 typedef __int16 int16_t;
15 typedef __int32 int32_t;
16 typedef __int64 int64_t;
17 typedef unsigned __int8 uint8_t;
18 typedef unsigned __int16 uint16_t;
19 typedef unsigned __int32 uint32_t;
20 typedef unsigned __int64 uint64_t;
21 #ifdef _WIN64
22 typedef __int64 intptr_t;
23 typedef unsigned __int64 uintptr_t;
24 #else
25 typedef __int32 intptr_t;
26 typedef unsigned __int32 uintptr_t;
27 #endif
28 #elif defined(__symbian__)
29 /* Cough. */
30 typedef signed char int8_t;
31 typedef short int int16_t;
32 typedef int int32_t;
33 typedef long long int64_t;
34 typedef unsigned char uint8_t;
35 typedef unsigned short int uint16_t;
36 typedef unsigned int uint32_t;
37 typedef unsigned long long uint64_t;
38 typedef int intptr_t;
39 typedef unsigned int uintptr_t;
40 #else
41 #include <stdint.h>
42 #endif
44 /* Needed everywhere. */
45 #include <string.h>
46 #include <stdlib.h>
48 /* Various VM limits. */
49 #define LJ_MAX_MEM 0x7fffff00 /* Max. total memory allocation. */
50 #define LJ_MAX_ALLOC LJ_MAX_MEM /* Max. individual allocation length. */
51 #define LJ_MAX_STR LJ_MAX_MEM /* Max. string length. */
52 #define LJ_MAX_UDATA LJ_MAX_MEM /* Max. userdata length. */
54 #define LJ_MAX_STRTAB (1<<26) /* Max. string table size. */
55 #define LJ_MAX_HBITS 26 /* Max. hash bits. */
56 #define LJ_MAX_ABITS 28 /* Max. bits of array key. */
57 #define LJ_MAX_ASIZE ((1<<(LJ_MAX_ABITS-1))+1) /* Max. array part size. */
58 #define LJ_MAX_COLOSIZE 16 /* Max. elems for colocated array. */
60 #define LJ_MAX_LINE LJ_MAX_MEM /* Max. source code line number. */
61 #define LJ_MAX_XLEVEL 200 /* Max. syntactic nesting level. */
62 #define LJ_MAX_BCINS (1<<26) /* Max. # of bytecode instructions. */
63 #define LJ_MAX_SLOTS 250 /* Max. # of slots in a Lua func. */
64 #define LJ_MAX_LOCVAR 200 /* Max. # of local variables. */
65 #define LJ_MAX_UPVAL 60 /* Max. # of upvalues. */
67 #define LJ_MAX_IDXCHAIN 100 /* __index/__newindex chain limit. */
68 #define LJ_STACK_EXTRA 5 /* Extra stack space (metamethods). */
70 #define LJ_NUM_CBPAGE 1 /* Number of FFI callback pages. */
72 /* Minimum table/buffer sizes. */
73 #define LJ_MIN_GLOBAL 6 /* Min. global table size (hbits). */
74 #define LJ_MIN_REGISTRY 2 /* Min. registry size (hbits). */
75 #define LJ_MIN_STRTAB 256 /* Min. string table size (pow2). */
76 #define LJ_MIN_SBUF 32 /* Min. string buffer length. */
77 #define LJ_MIN_VECSZ 8 /* Min. size for growable vectors. */
78 #define LJ_MIN_IRSZ 32 /* Min. size for growable IR. */
79 #define LJ_MIN_K64SZ 16 /* Min. size for chained K64Array. */
81 /* JIT compiler limits. */
82 #define LJ_MAX_JSLOTS 250 /* Max. # of stack slots for a trace. */
83 #define LJ_MAX_PHI 32 /* Max. # of PHIs for a loop. */
84 #define LJ_MAX_EXITSTUBGR 16 /* Max. # of exit stub groups. */
86 /* Various macros. */
87 #ifndef UNUSED
88 #define UNUSED(x) ((void)(x)) /* to avoid warnings */
89 #endif
91 #define U64x(hi, lo) (((uint64_t)0x##hi << 32) + (uint64_t)0x##lo)
92 #define i32ptr(p) ((int32_t)(intptr_t)(void *)(p))
93 #define u32ptr(p) ((uint32_t)(intptr_t)(void *)(p))
95 #define checki8(x) ((x) == (int32_t)(int8_t)(x))
96 #define checku8(x) ((x) == (int32_t)(uint8_t)(x))
97 #define checki16(x) ((x) == (int32_t)(int16_t)(x))
98 #define checku16(x) ((x) == (int32_t)(uint16_t)(x))
99 #define checki32(x) ((x) == (int32_t)(x))
100 #define checku32(x) ((x) == (uint32_t)(x))
101 #define checkptr32(x) ((uintptr_t)(x) == (uint32_t)(uintptr_t)(x))
103 /* Every half-decent C compiler transforms this into a rotate instruction. */
104 #define lj_rol(x, n) (((x)<<(n)) | ((x)>>(8*sizeof(x)-(n))))
105 #define lj_ror(x, n) (((x)<<(8*sizeof(x)-(n))) | ((x)>>(n)))
107 /* A really naive Bloom filter. But sufficient for our needs. */
108 typedef uintptr_t BloomFilter;
109 #define BLOOM_MASK (8*sizeof(BloomFilter) - 1)
110 #define bloombit(x) ((uintptr_t)1 << ((x) & BLOOM_MASK))
111 #define bloomset(b, x) ((b) |= bloombit((x)))
112 #define bloomtest(b, x) ((b) & bloombit((x)))
114 #if defined(__GNUC__)
116 #define LJ_NORET __attribute__((noreturn))
117 #define LJ_ALIGN(n) __attribute__((aligned(n)))
118 #define LJ_INLINE inline
119 #define LJ_AINLINE inline __attribute__((always_inline))
120 #define LJ_NOINLINE __attribute__((noinline))
122 #if defined(__ELF__) || defined(__MACH__)
123 #if !((defined(__sun__) && defined(__svr4__)) || defined(__solaris__))
124 #define LJ_NOAPI extern __attribute__((visibility("hidden")))
125 #endif
126 #endif
128 /* Note: it's only beneficial to use fastcall on x86 and then only for up to
129 ** two non-FP args. The amalgamated compile covers all LJ_FUNC cases. Only
130 ** indirect calls and related tail-called C functions are marked as fastcall.
132 #if defined(__i386__)
133 #define LJ_FASTCALL __attribute__((fastcall))
134 #endif
136 #define LJ_LIKELY(x) __builtin_expect(!!(x), 1)
137 #define LJ_UNLIKELY(x) __builtin_expect(!!(x), 0)
139 #define lj_ffs(x) ((uint32_t)__builtin_ctz(x))
140 /* Don't ask ... */
141 #if defined(__INTEL_COMPILER) && (defined(__i386__) || defined(__x86_64__))
142 static LJ_AINLINE uint32_t lj_fls(uint32_t x)
144 uint32_t r; __asm__("bsrl %1, %0" : "=r" (r) : "rm" (x) : "cc"); return r;
146 #else
147 #define lj_fls(x) ((uint32_t)(__builtin_clz(x)^31))
148 #endif
150 #if defined(__arm__)
151 static LJ_AINLINE uint32_t lj_bswap(uint32_t x)
153 uint32_t r;
154 #if __ARM_ARCH_6__ || __ARM_ARCH_6J__ || __ARM_ARCH_6T2__ || __ARM_ARCH_6Z__ ||\
155 __ARM_ARCH_6ZK__ || __ARM_ARCH_7__ || __ARM_ARCH_7A__ || __ARM_ARCH_7R__
156 __asm__("rev %0, %1" : "=r" (r) : "r" (x));
157 return r;
158 #else
159 #ifdef __thumb__
160 r = x ^ lj_ror(x, 16);
161 #else
162 __asm__("eor %0, %1, %1, ror #16" : "=r" (r) : "r" (x));
163 #endif
164 return ((r & 0xff00ffffu) >> 8) ^ lj_ror(x, 8);
165 #endif
168 static LJ_AINLINE uint64_t lj_bswap64(uint64_t x)
170 return ((uint64_t)lj_bswap((uint32_t)x)<<32) | lj_bswap((uint32_t)(x>>32));
172 #elif (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
173 static LJ_AINLINE uint32_t lj_bswap(uint32_t x)
175 return (uint32_t)__builtin_bswap32((int32_t)x);
178 static LJ_AINLINE uint64_t lj_bswap64(uint64_t x)
180 return (uint64_t)__builtin_bswap64((int64_t)x);
182 #elif defined(__i386__) || defined(__x86_64__)
183 static LJ_AINLINE uint32_t lj_bswap(uint32_t x)
185 uint32_t r; __asm__("bswap %0" : "=r" (r) : "0" (x)); return r;
188 #if defined(__i386__)
189 static LJ_AINLINE uint64_t lj_bswap64(uint64_t x)
191 return ((uint64_t)lj_bswap((uint32_t)x)<<32) | lj_bswap((uint32_t)(x>>32));
193 #else
194 static LJ_AINLINE uint64_t lj_bswap64(uint64_t x)
196 uint64_t r; __asm__("bswap %0" : "=r" (r) : "0" (x)); return r;
198 #endif
199 #else
200 #error "missing define for lj_bswap()"
201 #endif
203 typedef union __attribute__((packed)) Unaligned16 {
204 uint16_t u;
205 uint8_t b[2];
206 } Unaligned16;
208 typedef union __attribute__((packed)) Unaligned32 {
209 uint32_t u;
210 uint8_t b[4];
211 } Unaligned32;
213 /* Unaligned load of uint16_t. */
214 static LJ_AINLINE uint16_t lj_getu16(const void *p)
216 return ((const Unaligned16 *)p)->u;
219 /* Unaligned load of uint32_t. */
220 static LJ_AINLINE uint32_t lj_getu32(const void *p)
222 return ((const Unaligned32 *)p)->u;
225 #elif defined(_MSC_VER)
227 #define LJ_NORET __declspec(noreturn)
228 #define LJ_ALIGN(n) __declspec(align(n))
229 #define LJ_INLINE __inline
230 #define LJ_AINLINE __forceinline
231 #define LJ_NOINLINE __declspec(noinline)
232 #if defined(_M_IX86)
233 #define LJ_FASTCALL __fastcall
234 #endif
236 static LJ_AINLINE uint32_t lj_ffs(uint32_t x)
238 uint32_t r; _BitScanForward(&r, x); return r;
241 static LJ_AINLINE uint32_t lj_fls(uint32_t x)
243 uint32_t r; _BitScanReverse(&r, x); return r;
246 #define lj_bswap(x) (_byteswap_ulong((x)))
247 #define lj_bswap64(x) (_byteswap_uint64((x)))
249 /* MSVC is only supported on x86/x64, where unaligned loads are always ok. */
250 #define lj_getu16(p) (*(uint16_t *)(p))
251 #define lj_getu32(p) (*(uint32_t *)(p))
253 #else
254 #error "missing defines for your compiler"
255 #endif
257 /* Optional defines. */
258 #ifndef LJ_FASTCALL
259 #define LJ_FASTCALL
260 #endif
261 #ifndef LJ_NORET
262 #define LJ_NORET
263 #endif
264 #ifndef LJ_NOAPI
265 #define LJ_NOAPI extern
266 #endif
267 #ifndef LJ_LIKELY
268 #define LJ_LIKELY(x) (x)
269 #define LJ_UNLIKELY(x) (x)
270 #endif
272 /* Attributes for internal functions. */
273 #define LJ_DATA LJ_NOAPI
274 #define LJ_DATADEF
275 #define LJ_ASMF LJ_NOAPI
276 #define LJ_FUNCA LJ_NOAPI
277 #if defined(ljamalg_c)
278 #define LJ_FUNC static
279 #else
280 #define LJ_FUNC LJ_NOAPI
281 #endif
282 #define LJ_FUNC_NORET LJ_FUNC LJ_NORET
283 #define LJ_FUNCA_NORET LJ_FUNCA LJ_NORET
284 #define LJ_ASMF_NORET LJ_ASMF LJ_NORET
286 /* Runtime assertions. */
287 #ifdef lua_assert
288 #define check_exp(c, e) (lua_assert(c), (e))
289 #define api_check(l, e) lua_assert(e)
290 #else
291 #define lua_assert(c) ((void)0)
292 #define check_exp(c, e) (e)
293 #define api_check luai_apicheck
294 #endif
296 /* Static assertions. */
297 #define LJ_ASSERT_NAME2(name, line) name ## line
298 #define LJ_ASSERT_NAME(line) LJ_ASSERT_NAME2(lj_assert_, line)
299 #ifdef __COUNTER__
300 #define LJ_STATIC_ASSERT(cond) \
301 extern void LJ_ASSERT_NAME(__COUNTER__)(int STATIC_ASSERTION_FAILED[(cond)?1:-1])
302 #else
303 #define LJ_STATIC_ASSERT(cond) \
304 extern void LJ_ASSERT_NAME(__LINE__)(int STATIC_ASSERTION_FAILED[(cond)?1:-1])
305 #endif
307 #endif