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Diffstat (limited to 'source/luametatex/source/luacore/lua54/src/lparser.h')
| -rw-r--r-- | source/luametatex/source/luacore/lua54/src/lparser.h | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/source/luametatex/source/luacore/lua54/src/lparser.h b/source/luametatex/source/luacore/lua54/src/lparser.h new file mode 100644 index 000000000..5e4500f18 --- /dev/null +++ b/source/luametatex/source/luacore/lua54/src/lparser.h @@ -0,0 +1,171 @@ +/* +** $Id: lparser.h $ +** Lua Parser +** See Copyright Notice in lua.h +*/ + +#ifndef lparser_h +#define lparser_h + +#include "llimits.h" +#include "lobject.h" +#include "lzio.h" + + +/* +** Expression and variable descriptor. +** Code generation for variables and expressions can be delayed to allow +** optimizations; An 'expdesc' structure describes a potentially-delayed +** variable/expression. It has a description of its "main" value plus a +** list of conditional jumps that can also produce its value (generated +** by short-circuit operators 'and'/'or'). +*/ + +/* kinds of variables/expressions */ +typedef enum { + VVOID, /* when 'expdesc' describes the last expression of a list, + this kind means an empty list (so, no expression) */ + VNIL, /* constant nil */ + VTRUE, /* constant true */ + VFALSE, /* constant false */ + VK, /* constant in 'k'; info = index of constant in 'k' */ + VKFLT, /* floating constant; nval = numerical float value */ + VKINT, /* integer constant; ival = numerical integer value */ + VKSTR, /* string constant; strval = TString address; + (string is fixed by the lexer) */ + VNONRELOC, /* expression has its value in a fixed register; + info = result register */ + VLOCAL, /* local variable; var.ridx = register index; + var.vidx = relative index in 'actvar.arr' */ + VUPVAL, /* upvalue variable; info = index of upvalue in 'upvalues' */ + VCONST, /* compile-time <const> variable; + info = absolute index in 'actvar.arr' */ + VINDEXED, /* indexed variable; + ind.t = table register; + ind.idx = key's R index */ + VINDEXUP, /* indexed upvalue; + ind.t = table upvalue; + ind.idx = key's K index */ + VINDEXI, /* indexed variable with constant integer; + ind.t = table register; + ind.idx = key's value */ + VINDEXSTR, /* indexed variable with literal string; + ind.t = table register; + ind.idx = key's K index */ + VJMP, /* expression is a test/comparison; + info = pc of corresponding jump instruction */ + VRELOC, /* expression can put result in any register; + info = instruction pc */ + VCALL, /* expression is a function call; info = instruction pc */ + VVARARG /* vararg expression; info = instruction pc */ +} expkind; + + +#define vkisvar(k) (VLOCAL <= (k) && (k) <= VINDEXSTR) +#define vkisindexed(k) (VINDEXED <= (k) && (k) <= VINDEXSTR) + + +typedef struct expdesc { + expkind k; + union { + lua_Integer ival; /* for VKINT */ + lua_Number nval; /* for VKFLT */ + TString *strval; /* for VKSTR */ + int info; /* for generic use */ + struct { /* for indexed variables */ + short idx; /* index (R or "long" K) */ + lu_byte t; /* table (register or upvalue) */ + } ind; + struct { /* for local variables */ + lu_byte ridx; /* register holding the variable */ + unsigned short vidx; /* compiler index (in 'actvar.arr') */ + } var; + } u; + int t; /* patch list of 'exit when true' */ + int f; /* patch list of 'exit when false' */ +} expdesc; + + +/* kinds of variables */ +#define VDKREG 0 /* regular */ +#define RDKCONST 1 /* constant */ +#define RDKTOCLOSE 2 /* to-be-closed */ +#define RDKCTC 3 /* compile-time constant */ + +/* description of an active local variable */ +typedef union Vardesc { + struct { + TValuefields; /* constant value (if it is a compile-time constant) */ + lu_byte kind; + lu_byte ridx; /* register holding the variable */ + short pidx; /* index of the variable in the Proto's 'locvars' array */ + TString *name; /* variable name */ + } vd; + TValue k; /* constant value (if any) */ +} Vardesc; + + + +/* description of pending goto statements and label statements */ +typedef struct Labeldesc { + TString *name; /* label identifier */ + int pc; /* position in code */ + int line; /* line where it appeared */ + lu_byte nactvar; /* number of active variables in that position */ + lu_byte close; /* goto that escapes upvalues */ +} Labeldesc; + + +/* list of labels or gotos */ +typedef struct Labellist { + Labeldesc *arr; /* array */ + int n; /* number of entries in use */ + int size; /* array size */ +} Labellist; + + +/* dynamic structures used by the parser */ +typedef struct Dyndata { + struct { /* list of all active local variables */ + Vardesc *arr; + int n; + int size; + } actvar; + Labellist gt; /* list of pending gotos */ + Labellist label; /* list of active labels */ +} Dyndata; + + +/* control of blocks */ +struct BlockCnt; /* defined in lparser.c */ + + +/* state needed to generate code for a given function */ +typedef struct FuncState { + Proto *f; /* current function header */ + struct FuncState *prev; /* enclosing function */ + struct LexState *ls; /* lexical state */ + struct BlockCnt *bl; /* chain of current blocks */ + int pc; /* next position to code (equivalent to 'ncode') */ + int lasttarget; /* 'label' of last 'jump label' */ + int previousline; /* last line that was saved in 'lineinfo' */ + int nk; /* number of elements in 'k' */ + int np; /* number of elements in 'p' */ + int nabslineinfo; /* number of elements in 'abslineinfo' */ + int firstlocal; /* index of first local var (in Dyndata array) */ + int firstlabel; /* index of first label (in 'dyd->label->arr') */ + short ndebugvars; /* number of elements in 'f->locvars' */ + lu_byte nactvar; /* number of active local variables */ + lu_byte nups; /* number of upvalues */ + lu_byte freereg; /* first free register */ + lu_byte iwthabs; /* instructions issued since last absolute line info */ + lu_byte needclose; /* function needs to close upvalues when returning */ +} FuncState; + + +LUAI_FUNC int luaY_nvarstack (FuncState *fs); +LUAI_FUNC LClosure *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff, + Dyndata *dyd, const char *name, int firstchar); + + +#endif |