luau/VM/src/lstate.h
2022-03-04 08:36:33 -08:00

287 lines
9.9 KiB
C

// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
// This code is based on Lua 5.x implementation licensed under MIT License; see lua_LICENSE.txt for details
#pragma once
#include "lobject.h"
#include "ltm.h"
/* registry */
#define registry(L) (&L->global->registry)
/* extra stack space to handle TM calls and some other extras */
#define EXTRA_STACK 5
#define BASIC_CI_SIZE 8
#define BASIC_STACK_SIZE (2 * LUA_MINSTACK)
// clang-format off
typedef struct stringtable
{
TString** hash;
uint32_t nuse; /* number of elements */
int size;
} stringtable;
// clang-format on
/*
** informations about a call
**
** the general Lua stack frame structure is as follows:
** - each function gets a stack frame, with function "registers" being stack slots on the frame
** - function arguments are associated with registers 0+
** - function locals and temporaries follow after; usually locals are a consecutive block per scope, and temporaries are allocated after this, but
*this is up to the compiler
**
** when function doesn't have varargs, the stack layout is as follows:
** ^ (func) ^^ [fixed args] [locals + temporaries]
** where ^ is the 'func' pointer in CallInfo struct, and ^^ is the 'base' pointer (which is what registers are relative to)
**
** when function *does* have varargs, the stack layout is more complex - the runtime has to copy the fixed arguments so that the 0+ addressing still
*works as follows:
** ^ (func) [fixed args] [varargs] ^^ [fixed args] [locals + temporaries]
**
** computing the sizes of these individual blocks works as follows:
** - the number of fixed args is always matching the `numparams` in a function's Proto object; runtime adds `nil` during the call execution as
*necessary
** - the number of variadic args can be computed by evaluating (ci->base - ci->func - 1 - numparams)
**
** the CallInfo structures are allocated as an array, with each subsequent call being *appended* to this array (so if f calls g, CallInfo for g
*immediately follows CallInfo for f)
** the `nresults` field in CallInfo is set by the caller to tell the function how many arguments the caller is expecting on the stack after the
*function returns
** the `flags` field in CallInfo contains internal execution flags that are important for pcall/etc, see LUA_CALLINFO_*
*/
// clang-format off
typedef struct CallInfo
{
StkId base; /* base for this function */
StkId func; /* function index in the stack */
StkId top; /* top for this function */
const Instruction* savedpc;
int nresults; /* expected number of results from this function */
unsigned int flags; /* call frame flags, see LUA_CALLINFO_* */
} CallInfo;
// clang-format on
#define LUA_CALLINFO_RETURN (1 << 0) /* should the interpreter return after returning from this callinfo? first frame must have this set */
#define LUA_CALLINFO_HANDLE (1 << 1) /* should the error thrown during execution get handled by continuation from this callinfo? func must be C */
#define curr_func(L) (clvalue(L->ci->func))
#define ci_func(ci) (clvalue((ci)->func))
#define f_isLua(ci) (!ci_func(ci)->isC)
#define isLua(ci) (ttisfunction((ci)->func) && f_isLua(ci))
struct GCCycleStats
{
size_t starttotalsizebytes = 0;
size_t heapgoalsizebytes = 0;
size_t heaptriggersizebytes = 0;
double pausetime = 0.0; // time from end of the last cycle to the start of a new one
double starttimestamp = 0.0;
double endtimestamp = 0.0;
double marktime = 0.0;
double markassisttime = 0.0;
double markmaxexplicittime = 0.0;
size_t markexplicitsteps = 0;
size_t markrequests = 0;
double atomicstarttimestamp = 0.0;
size_t atomicstarttotalsizebytes = 0;
double atomictime = 0.0;
// specific atomic stage parts
double atomictimeupval = 0.0;
double atomictimeweak = 0.0;
double atomictimegray = 0.0;
double atomictimeclear = 0.0;
double sweeptime = 0.0;
double sweepassisttime = 0.0;
double sweepmaxexplicittime = 0.0;
size_t sweepexplicitsteps = 0;
size_t sweeprequests = 0;
size_t assistrequests = 0;
size_t explicitrequests = 0;
size_t assistwork = 0;
size_t explicitwork = 0;
size_t propagatework = 0;
size_t propagateagainwork = 0;
size_t endtotalsizebytes = 0;
};
// data for proportional-integral controller of heap trigger value
struct GCHeapTriggerStats
{
static const unsigned termcount = 32;
int32_t terms[termcount] = {0};
uint32_t termpos = 0;
int32_t integral = 0;
};
struct GCStats
{
double stepexplicittimeacc = 0.0;
double stepassisttimeacc = 0.0;
// when cycle is completed, last cycle values are updated
uint64_t completedcycles = 0;
GCCycleStats lastcycle;
GCCycleStats currcycle;
// only step count and their time is accumulated
GCCycleStats cyclestatsacc;
GCHeapTriggerStats triggerstats;
};
/*
** `global state', shared by all threads of this state
*/
// clang-format off
typedef struct global_State
{
stringtable strt; /* hash table for strings */
lua_Alloc frealloc; /* function to reallocate memory */
void* ud; /* auxiliary data to `frealloc' */
uint8_t currentwhite;
uint8_t gcstate; /* state of garbage collector */
GCObject* gray; /* list of gray objects */
GCObject* grayagain; /* list of objects to be traversed atomically */
GCObject* weak; /* list of weak tables (to be cleared) */
TString* strbufgc; // list of all string buffer objects
size_t GCthreshold; // when totalbytes > GCthreshold; run GC step
size_t totalbytes; // number of bytes currently allocated
int gcgoal; // see LUAI_GCGOAL
int gcstepmul; // see LUAI_GCSTEPMUL
int gcstepsize; // see LUAI_GCSTEPSIZE
struct lua_Page* freepages[LUA_SIZECLASSES]; // free page linked list for each size class for non-collectable objects
struct lua_Page* freegcopages[LUA_SIZECLASSES]; // free page linked list for each size class for collectable objects
struct lua_Page* allgcopages; // page linked list with all pages for all classes
struct lua_Page* sweepgcopage; // position of the sweep in `allgcopages'
size_t memcatbytes[LUA_MEMORY_CATEGORIES]; /* total amount of memory used by each memory category */
struct lua_State* mainthread;
UpVal uvhead; /* head of double-linked list of all open upvalues */
struct Table* mt[LUA_T_COUNT]; /* metatables for basic types */
TString* ttname[LUA_T_COUNT]; /* names for basic types */
TString* tmname[TM_N]; /* array with tag-method names */
TValue pseudotemp; /* storage for temporary values used in pseudo2addr */
TValue registry; /* registry table, used by lua_ref and LUA_REGISTRYINDEX */
int registryfree; /* next free slot in registry */
struct lua_jmpbuf* errorjmp; /* jump buffer data for longjmp-style error handling */
uint64_t rngstate; /* PCG random number generator state */
uint64_t ptrenckey[4]; /* pointer encoding key for display */
void (*udatagc[LUA_UTAG_LIMIT])(void*); /* for each userdata tag, a gc callback to be called immediately before freeing memory */
lua_Callbacks cb;
GCStats gcstats;
} global_State;
// clang-format on
/*
** `per thread' state
*/
// clang-format off
struct lua_State
{
CommonHeader;
uint8_t status;
uint8_t activememcat; /* memory category that is used for new GC object allocations */
uint8_t stackstate;
bool singlestep; /* call debugstep hook after each instruction */
StkId top; /* first free slot in the stack */
StkId base; /* base of current function */
global_State* global;
CallInfo* ci; /* call info for current function */
StkId stack_last; /* last free slot in the stack */
StkId stack; /* stack base */
CallInfo* end_ci; /* points after end of ci array*/
CallInfo* base_ci; /* array of CallInfo's */
int stacksize;
int size_ci; /* size of array `base_ci' */
unsigned short nCcalls; /* number of nested C calls */
unsigned short baseCcalls; /* nested C calls when resuming coroutine */
int cachedslot; /* when table operations or INDEX/NEWINDEX is invoked from Luau, what is the expected slot for lookup? */
Table* gt; /* table of globals */
UpVal* openupval; /* list of open upvalues in this stack */
GCObject* gclist;
TString* namecall; /* when invoked from Luau using NAMECALL, what method do we need to invoke? */
void* userdata;
};
// clang-format on
/*
** Union of all collectible objects
*/
union GCObject
{
GCheader gch;
struct TString ts;
struct Udata u;
struct Closure cl;
struct Table h;
struct Proto p;
struct UpVal uv;
struct lua_State th; /* thread */
};
/* macros to convert a GCObject into a specific value */
#define gco2ts(o) check_exp((o)->gch.tt == LUA_TSTRING, &((o)->ts))
#define gco2u(o) check_exp((o)->gch.tt == LUA_TUSERDATA, &((o)->u))
#define gco2cl(o) check_exp((o)->gch.tt == LUA_TFUNCTION, &((o)->cl))
#define gco2h(o) check_exp((o)->gch.tt == LUA_TTABLE, &((o)->h))
#define gco2p(o) check_exp((o)->gch.tt == LUA_TPROTO, &((o)->p))
#define gco2uv(o) check_exp((o)->gch.tt == LUA_TUPVAL, &((o)->uv))
#define gco2th(o) check_exp((o)->gch.tt == LUA_TTHREAD, &((o)->th))
/* macro to convert any Lua object into a GCObject */
#define obj2gco(v) check_exp(iscollectable(v), cast_to(GCObject*, (v) + 0))
LUAI_FUNC lua_State* luaE_newthread(lua_State* L);
LUAI_FUNC void luaE_freethread(lua_State* L, lua_State* L1, struct lua_Page* page);