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** $Id: llimits.h,v 1.1 2003/02/09 21:30:32 dheck Exp $
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** Limits, basic types, and some other "installation-dependent" definitions
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** See Copyright Notice in lua.h
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** try to find number of bits in an integer
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/* avoid overflows in comparison */
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#if INT_MAX-20 < 32760
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#if INT_MAX > 2147483640L
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/* machine has at least 32 bits */
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#error "you must define BITS_INT with number of bits in an integer"
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** Define the type `number' of Lua
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** GREP LUA_NUMBER to change that
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#define LUA_NUM_TYPE double
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typedef LUA_NUM_TYPE Number;
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/* function to convert a Number to a string */
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#define NUMBER_FMT "%.16g" /* LUA_NUMBER */
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#define lua_number2str(s,n) sprintf((s), NUMBER_FMT, (n))
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/* function to convert a string to a Number */
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#define lua_str2number(s,p) strtod((s), (p))
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typedef unsigned long lint32; /* unsigned int with at least 32 bits */
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#define MAX_SIZET ((size_t)(~(size_t)0)-2)
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#define MAX_INT (INT_MAX-2) /* maximum value of an int (-2 for safety) */
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** conversion of pointer to int (for hashing only)
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** (the shift removes bits that are usually 0 because of alignment)
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#define IntPoint(p) (((unsigned long)(p)) >> 3)
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#define MINPOWER2 4 /* minimum size for "growing" vectors */
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#ifndef DEFAULT_STACK_SIZE
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#define DEFAULT_STACK_SIZE 1024
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/* type to ensure maximum alignment */
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union L_Umaxalign { double d; char *s; long l; };
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** type for virtual-machine instructions
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** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)
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** For a very small machine, you may change that to 2 bytes (and adjust
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** the following limits accordingly)
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typedef unsigned long Instruction;
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** size and position of opcode arguments.
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** For an instruction with 2 bytes, size is 16, and size_b can be 5
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** (accordingly, size_u will be 10, and size_a will be 5)
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#define SIZE_INSTRUCTION 32
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#define SIZE_U (SIZE_INSTRUCTION-SIZE_OP)
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#define POS_U SIZE_OP
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#define POS_B SIZE_OP
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#define SIZE_A (SIZE_INSTRUCTION-(SIZE_OP+SIZE_B))
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#define POS_A (SIZE_OP+SIZE_B)
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** limits for opcode arguments.
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** we use (signed) int to manipulate most arguments,
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** so they must fit in BITS_INT-1 bits (-1 for sign)
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#if SIZE_U < BITS_INT-1
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#define MAXARG_U ((1<<SIZE_U)-1)
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#define MAXARG_S (MAXARG_U>>1) /* `S' is signed */
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#define MAXARG_U MAX_INT
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#define MAXARG_S MAX_INT
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#if SIZE_A < BITS_INT-1
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#define MAXARG_A ((1<<SIZE_A)-1)
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#define MAXARG_A MAX_INT
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#if SIZE_B < BITS_INT-1
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#define MAXARG_B ((1<<SIZE_B)-1)
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#define MAXARG_B MAX_INT
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/* maximum stack size in a function */
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#if MAXSTACK > MAXARG_B
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#define MAXSTACK MAXARG_B
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/* maximum number of local variables */
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#define MAXLOCALS 200 /* arbitrary limit (<MAXSTACK) */
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#if MAXLOCALS>=MAXSTACK
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#define MAXLOCALS (MAXSTACK-1)
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/* maximum number of upvalues */
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#define MAXUPVALUES 32 /* arbitrary limit (<=MAXARG_B) */
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#if MAXUPVALUES>MAXARG_B
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#define MAXUPVALUES MAXARG_B
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/* maximum number of variables in the left side of an assignment */
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#define MAXVARSLH 100 /* arbitrary limit (<MULT_RET) */
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#if MAXVARSLH>=MULT_RET
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#define MAXVARSLH (MULT_RET-1)
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/* maximum number of parameters in a function */
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#define MAXPARAMS 100 /* arbitrary limit (<MAXLOCALS) */
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#if MAXPARAMS>=MAXLOCALS
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#define MAXPARAMS (MAXLOCALS-1)
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/* number of list items to accumulate before a SETLIST instruction */
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#define LFIELDS_PER_FLUSH 64
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#if LFIELDS_PER_FLUSH>(MAXSTACK/4)
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#undef LFIELDS_PER_FLUSH
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#define LFIELDS_PER_FLUSH (MAXSTACK/4)
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/* number of record items to accumulate before a SETMAP instruction */
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/* (each item counts 2 elements on the stack: an index and a value) */
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#define RFIELDS_PER_FLUSH (LFIELDS_PER_FLUSH/2)
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/* maximum lookback to find a real constant (for code generation) */
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#define LOOKBACKNUMS 20 /* arbitrary constant */
added
removed
lib-src/lua/llimits.h
