diff options
Diffstat (limited to '3rdparty/lua/src/lcode.c')
-rw-r--r-- | 3rdparty/lua/src/lcode.c | 1203 |
1 files changed, 0 insertions, 1203 deletions
diff --git a/3rdparty/lua/src/lcode.c b/3rdparty/lua/src/lcode.c deleted file mode 100644 index 0bb4142..0000000 --- a/3rdparty/lua/src/lcode.c +++ /dev/null @@ -1,1203 +0,0 @@ -/* -** $Id: lcode.c,v 2.112 2016/12/22 13:08:50 roberto Exp $ -** Code generator for Lua -** See Copyright Notice in lua.h -*/ - -#define lcode_c -#define LUA_CORE - -#include "lprefix.h" - - -#include <math.h> -#include <stdlib.h> - -#include "lua.h" - -#include "lcode.h" -#include "ldebug.h" -#include "ldo.h" -#include "lgc.h" -#include "llex.h" -#include "lmem.h" -#include "lobject.h" -#include "lopcodes.h" -#include "lparser.h" -#include "lstring.h" -#include "ltable.h" -#include "lvm.h" - - -/* Maximum number of registers in a Lua function (must fit in 8 bits) */ -#define MAXREGS 255 - - -#define hasjumps(e) ((e)->t != (e)->f) - - -/* -** If expression is a numeric constant, fills 'v' with its value -** and returns 1. Otherwise, returns 0. -*/ -static int tonumeral(const expdesc *e, TValue *v) { - if (hasjumps(e)) - return 0; /* not a numeral */ - switch (e->k) { - case VKINT: - if (v) setivalue(v, e->u.ival); - return 1; - case VKFLT: - if (v) setfltvalue(v, e->u.nval); - return 1; - default: return 0; - } -} - - -/* -** Create a OP_LOADNIL instruction, but try to optimize: if the previous -** instruction is also OP_LOADNIL and ranges are compatible, adjust -** range of previous instruction instead of emitting a new one. (For -** instance, 'local a; local b' will generate a single opcode.) -*/ -void luaK_nil (FuncState *fs, int from, int n) { - Instruction *previous; - int l = from + n - 1; /* last register to set nil */ - if (fs->pc > fs->lasttarget) { /* no jumps to current position? */ - previous = &fs->f->code[fs->pc-1]; - if (GET_OPCODE(*previous) == OP_LOADNIL) { /* previous is LOADNIL? */ - int pfrom = GETARG_A(*previous); /* get previous range */ - int pl = pfrom + GETARG_B(*previous); - if ((pfrom <= from && from <= pl + 1) || - (from <= pfrom && pfrom <= l + 1)) { /* can connect both? */ - if (pfrom < from) from = pfrom; /* from = min(from, pfrom) */ - if (pl > l) l = pl; /* l = max(l, pl) */ - SETARG_A(*previous, from); - SETARG_B(*previous, l - from); - return; - } - } /* else go through */ - } - luaK_codeABC(fs, OP_LOADNIL, from, n - 1, 0); /* else no optimization */ -} - - -/* -** Gets the destination address of a jump instruction. Used to traverse -** a list of jumps. -*/ -static int getjump (FuncState *fs, int pc) { - int offset = GETARG_sBx(fs->f->code[pc]); - if (offset == NO_JUMP) /* point to itself represents end of list */ - return NO_JUMP; /* end of list */ - else - return (pc+1)+offset; /* turn offset into absolute position */ -} - - -/* -** Fix jump instruction at position 'pc' to jump to 'dest'. -** (Jump addresses are relative in Lua) -*/ -static void fixjump (FuncState *fs, int pc, int dest) { - Instruction *jmp = &fs->f->code[pc]; - int offset = dest - (pc + 1); - lua_assert(dest != NO_JUMP); - if (abs(offset) > MAXARG_sBx) - luaX_syntaxerror(fs->ls, "control structure too long"); - SETARG_sBx(*jmp, offset); -} - - -/* -** Concatenate jump-list 'l2' into jump-list 'l1' -*/ -void luaK_concat (FuncState *fs, int *l1, int l2) { - if (l2 == NO_JUMP) return; /* nothing to concatenate? */ - else if (*l1 == NO_JUMP) /* no original list? */ - *l1 = l2; /* 'l1' points to 'l2' */ - else { - int list = *l1; - int next; - while ((next = getjump(fs, list)) != NO_JUMP) /* find last element */ - list = next; - fixjump(fs, list, l2); /* last element links to 'l2' */ - } -} - - -/* -** Create a jump instruction and return its position, so its destination -** can be fixed later (with 'fixjump'). If there are jumps to -** this position (kept in 'jpc'), link them all together so that -** 'patchlistaux' will fix all them directly to the final destination. -*/ -int luaK_jump (FuncState *fs) { - int jpc = fs->jpc; /* save list of jumps to here */ - int j; - fs->jpc = NO_JUMP; /* no more jumps to here */ - j = luaK_codeAsBx(fs, OP_JMP, 0, NO_JUMP); - luaK_concat(fs, &j, jpc); /* keep them on hold */ - return j; -} - - -/* -** Code a 'return' instruction -*/ -void luaK_ret (FuncState *fs, int first, int nret) { - luaK_codeABC(fs, OP_RETURN, first, nret+1, 0); -} - - -/* -** Code a "conditional jump", that is, a test or comparison opcode -** followed by a jump. Return jump position. -*/ -static int condjump (FuncState *fs, OpCode op, int A, int B, int C) { - luaK_codeABC(fs, op, A, B, C); - return luaK_jump(fs); -} - - -/* -** returns current 'pc' and marks it as a jump target (to avoid wrong -** optimizations with consecutive instructions not in the same basic block). -*/ -int luaK_getlabel (FuncState *fs) { - fs->lasttarget = fs->pc; - return fs->pc; -} - - -/* -** Returns the position of the instruction "controlling" a given -** jump (that is, its condition), or the jump itself if it is -** unconditional. -*/ -static Instruction *getjumpcontrol (FuncState *fs, int pc) { - Instruction *pi = &fs->f->code[pc]; - if (pc >= 1 && testTMode(GET_OPCODE(*(pi-1)))) - return pi-1; - else - return pi; -} - - -/* -** Patch destination register for a TESTSET instruction. -** If instruction in position 'node' is not a TESTSET, return 0 ("fails"). -** Otherwise, if 'reg' is not 'NO_REG', set it as the destination -** register. Otherwise, change instruction to a simple 'TEST' (produces -** no register value) -*/ -static int patchtestreg (FuncState *fs, int node, int reg) { - Instruction *i = getjumpcontrol(fs, node); - if (GET_OPCODE(*i) != OP_TESTSET) - return 0; /* cannot patch other instructions */ - if (reg != NO_REG && reg != GETARG_B(*i)) - SETARG_A(*i, reg); - else { - /* no register to put value or register already has the value; - change instruction to simple test */ - *i = CREATE_ABC(OP_TEST, GETARG_B(*i), 0, GETARG_C(*i)); - } - return 1; -} - - -/* -** Traverse a list of tests ensuring no one produces a value -*/ -static void removevalues (FuncState *fs, int list) { - for (; list != NO_JUMP; list = getjump(fs, list)) - patchtestreg(fs, list, NO_REG); -} - - -/* -** Traverse a list of tests, patching their destination address and -** registers: tests producing values jump to 'vtarget' (and put their -** values in 'reg'), other tests jump to 'dtarget'. -*/ -static void patchlistaux (FuncState *fs, int list, int vtarget, int reg, - int dtarget) { - while (list != NO_JUMP) { - int next = getjump(fs, list); - if (patchtestreg(fs, list, reg)) - fixjump(fs, list, vtarget); - else - fixjump(fs, list, dtarget); /* jump to default target */ - list = next; - } -} - - -/* -** Ensure all pending jumps to current position are fixed (jumping -** to current position with no values) and reset list of pending -** jumps -*/ -static void dischargejpc (FuncState *fs) { - patchlistaux(fs, fs->jpc, fs->pc, NO_REG, fs->pc); - fs->jpc = NO_JUMP; -} - - -/* -** Add elements in 'list' to list of pending jumps to "here" -** (current position) -*/ -void luaK_patchtohere (FuncState *fs, int list) { - luaK_getlabel(fs); /* mark "here" as a jump target */ - luaK_concat(fs, &fs->jpc, list); -} - - -/* -** Path all jumps in 'list' to jump to 'target'. -** (The assert means that we cannot fix a jump to a forward address -** because we only know addresses once code is generated.) -*/ -void luaK_patchlist (FuncState *fs, int list, int target) { - if (target == fs->pc) /* 'target' is current position? */ - luaK_patchtohere(fs, list); /* add list to pending jumps */ - else { - lua_assert(target < fs->pc); - patchlistaux(fs, list, target, NO_REG, target); - } -} - - -/* -** Path all jumps in 'list' to close upvalues up to given 'level' -** (The assertion checks that jumps either were closing nothing -** or were closing higher levels, from inner blocks.) -*/ -void luaK_patchclose (FuncState *fs, int list, int level) { - level++; /* argument is +1 to reserve 0 as non-op */ - for (; list != NO_JUMP; list = getjump(fs, list)) { - lua_assert(GET_OPCODE(fs->f->code[list]) == OP_JMP && - (GETARG_A(fs->f->code[list]) == 0 || - GETARG_A(fs->f->code[list]) >= level)); - SETARG_A(fs->f->code[list], level); - } -} - - -/* -** Emit instruction 'i', checking for array sizes and saving also its -** line information. Return 'i' position. -*/ -static int luaK_code (FuncState *fs, Instruction i) { - Proto *f = fs->f; - dischargejpc(fs); /* 'pc' will change */ - /* put new instruction in code array */ - luaM_growvector(fs->ls->L, f->code, fs->pc, f->sizecode, Instruction, - MAX_INT, "opcodes"); - f->code[fs->pc] = i; - /* save corresponding line information */ - luaM_growvector(fs->ls->L, f->lineinfo, fs->pc, f->sizelineinfo, int, - MAX_INT, "opcodes"); - f->lineinfo[fs->pc] = fs->ls->lastline; - return fs->pc++; -} - - -/* -** Format and emit an 'iABC' instruction. (Assertions check consistency -** of parameters versus opcode.) -*/ -int luaK_codeABC (FuncState *fs, OpCode o, int a, int b, int c) { - lua_assert(getOpMode(o) == iABC); - lua_assert(getBMode(o) != OpArgN || b == 0); - lua_assert(getCMode(o) != OpArgN || c == 0); - lua_assert(a <= MAXARG_A && b <= MAXARG_B && c <= MAXARG_C); - return luaK_code(fs, CREATE_ABC(o, a, b, c)); -} - - -/* -** Format and emit an 'iABx' instruction. -*/ -int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) { - lua_assert(getOpMode(o) == iABx || getOpMode(o) == iAsBx); - lua_assert(getCMode(o) == OpArgN); - lua_assert(a <= MAXARG_A && bc <= MAXARG_Bx); - return luaK_code(fs, CREATE_ABx(o, a, bc)); -} - - -/* -** Emit an "extra argument" instruction (format 'iAx') -*/ -static int codeextraarg (FuncState *fs, int a) { - lua_assert(a <= MAXARG_Ax); - return luaK_code(fs, CREATE_Ax(OP_EXTRAARG, a)); -} - - -/* -** Emit a "load constant" instruction, using either 'OP_LOADK' -** (if constant index 'k' fits in 18 bits) or an 'OP_LOADKX' -** instruction with "extra argument". -*/ -int luaK_codek (FuncState *fs, int reg, int k) { - if (k <= MAXARG_Bx) - return luaK_codeABx(fs, OP_LOADK, reg, k); - else { - int p = luaK_codeABx(fs, OP_LOADKX, reg, 0); - codeextraarg(fs, k); - return p; - } -} - - -/* -** Check register-stack level, keeping track of its maximum size -** in field 'maxstacksize' -*/ -void luaK_checkstack (FuncState *fs, int n) { - int newstack = fs->freereg + n; - if (newstack > fs->f->maxstacksize) { - if (newstack >= MAXREGS) - luaX_syntaxerror(fs->ls, - "function or expression needs too many registers"); - fs->f->maxstacksize = cast_byte(newstack); - } -} - - -/* -** Reserve 'n' registers in register stack -*/ -void luaK_reserveregs (FuncState *fs, int n) { - luaK_checkstack(fs, n); - fs->freereg += n; -} - - -/* -** Free register 'reg', if it is neither a constant index nor -** a local variable. -) -*/ -static void freereg (FuncState *fs, int reg) { - if (!ISK(reg) && reg >= fs->nactvar) { - fs->freereg--; - lua_assert(reg == fs->freereg); - } -} - - -/* -** Free register used by expression 'e' (if any) -*/ -static void freeexp (FuncState *fs, expdesc *e) { - if (e->k == VNONRELOC) - freereg(fs, e->u.info); -} - - -/* -** Free registers used by expressions 'e1' and 'e2' (if any) in proper -** order. -*/ -static void freeexps (FuncState *fs, expdesc *e1, expdesc *e2) { - int r1 = (e1->k == VNONRELOC) ? e1->u.info : -1; - int r2 = (e2->k == VNONRELOC) ? e2->u.info : -1; - if (r1 > r2) { - freereg(fs, r1); - freereg(fs, r2); - } - else { - freereg(fs, r2); - freereg(fs, r1); - } -} - - -/* -** Add constant 'v' to prototype's list of constants (field 'k'). -** Use scanner's table to cache position of constants in constant list -** and try to reuse constants. Because some values should not be used -** as keys (nil cannot be a key, integer keys can collapse with float -** keys), the caller must provide a useful 'key' for indexing the cache. -*/ -static int addk (FuncState *fs, TValue *key, TValue *v) { - lua_State *L = fs->ls->L; - Proto *f = fs->f; - TValue *idx = luaH_set(L, fs->ls->h, key); /* index scanner table */ - int k, oldsize; - if (ttisinteger(idx)) { /* is there an index there? */ - k = cast_int(ivalue(idx)); - /* correct value? (warning: must distinguish floats from integers!) */ - if (k < fs->nk && ttype(&f->k[k]) == ttype(v) && - luaV_rawequalobj(&f->k[k], v)) - return k; /* reuse index */ - } - /* constant not found; create a new entry */ - oldsize = f->sizek; - k = fs->nk; - /* numerical value does not need GC barrier; - table has no metatable, so it does not need to invalidate cache */ - setivalue(idx, k); - luaM_growvector(L, f->k, k, f->sizek, TValue, MAXARG_Ax, "constants"); - while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]); - setobj(L, &f->k[k], v); - fs->nk++; - luaC_barrier(L, f, v); - return k; -} - - -/* -** Add a string to list of constants and return its index. -*/ -int luaK_stringK (FuncState *fs, TString *s) { - TValue o; - setsvalue(fs->ls->L, &o, s); - return addk(fs, &o, &o); /* use string itself as key */ -} - - -/* -** Add an integer to list of constants and return its index. -** Integers use userdata as keys to avoid collision with floats with -** same value; conversion to 'void*' is used only for hashing, so there -** are no "precision" problems. -*/ -int luaK_intK (FuncState *fs, lua_Integer n) { - TValue k, o; - setpvalue(&k, cast(void*, cast(size_t, n))); - setivalue(&o, n); - return addk(fs, &k, &o); -} - -/* -** Add a float to list of constants and return its index. -*/ -static int luaK_numberK (FuncState *fs, lua_Number r) { - TValue o; - setfltvalue(&o, r); - return addk(fs, &o, &o); /* use number itself as key */ -} - - -/* -** Add a boolean to list of constants and return its index. -*/ -static int boolK (FuncState *fs, int b) { - TValue o; - setbvalue(&o, b); - return addk(fs, &o, &o); /* use boolean itself as key */ -} - - -/* -** Add nil to list of constants and return its index. -*/ -static int nilK (FuncState *fs) { - TValue k, v; - setnilvalue(&v); - /* cannot use nil as key; instead use table itself to represent nil */ - sethvalue(fs->ls->L, &k, fs->ls->h); - return addk(fs, &k, &v); -} - - -/* -** Fix an expression to return the number of results 'nresults'. -** Either 'e' is a multi-ret expression (function call or vararg) -** or 'nresults' is LUA_MULTRET (as any expression can satisfy that). -*/ -void luaK_setreturns (FuncState *fs, expdesc *e, int nresults) { - if (e->k == VCALL) { /* expression is an open function call? */ - SETARG_C(getinstruction(fs, e), nresults + 1); - } - else if (e->k == VVARARG) { - Instruction *pc = &getinstruction(fs, e); - SETARG_B(*pc, nresults + 1); - SETARG_A(*pc, fs->freereg); - luaK_reserveregs(fs, 1); - } - else lua_assert(nresults == LUA_MULTRET); -} - - -/* -** Fix an expression to return one result. -** If expression is not a multi-ret expression (function call or -** vararg), it already returns one result, so nothing needs to be done. -** Function calls become VNONRELOC expressions (as its result comes -** fixed in the base register of the call), while vararg expressions -** become VRELOCABLE (as OP_VARARG puts its results where it wants). -** (Calls are created returning one result, so that does not need -** to be fixed.) -*/ -void luaK_setoneret (FuncState *fs, expdesc *e) { - if (e->k == VCALL) { /* expression is an open function call? */ - /* already returns 1 value */ - lua_assert(GETARG_C(getinstruction(fs, e)) == 2); - e->k = VNONRELOC; /* result has fixed position */ - e->u.info = GETARG_A(getinstruction(fs, e)); - } - else if (e->k == VVARARG) { - SETARG_B(getinstruction(fs, e), 2); - e->k = VRELOCABLE; /* can relocate its simple result */ - } -} - - -/* -** Ensure that expression 'e' is not a variable. -*/ -void luaK_dischargevars (FuncState *fs, expdesc *e) { - switch (e->k) { - case VLOCAL: { /* already in a register */ - e->k = VNONRELOC; /* becomes a non-relocatable value */ - break; - } - case VUPVAL: { /* move value to some (pending) register */ - e->u.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.info, 0); - e->k = VRELOCABLE; - break; - } - case VINDEXED: { - OpCode op; - freereg(fs, e->u.ind.idx); - if (e->u.ind.vt == VLOCAL) { /* is 't' in a register? */ - freereg(fs, e->u.ind.t); - op = OP_GETTABLE; - } - else { - lua_assert(e->u.ind.vt == VUPVAL); - op = OP_GETTABUP; /* 't' is in an upvalue */ - } - e->u.info = luaK_codeABC(fs, op, 0, e->u.ind.t, e->u.ind.idx); - e->k = VRELOCABLE; - break; - } - case VVARARG: case VCALL: { - luaK_setoneret(fs, e); - break; - } - default: break; /* there is one value available (somewhere) */ - } -} - - -/* -** Ensures expression value is in register 'reg' (and therefore -** 'e' will become a non-relocatable expression). -*/ -static void discharge2reg (FuncState *fs, expdesc *e, int reg) { - luaK_dischargevars(fs, e); - switch (e->k) { - case VNIL: { - luaK_nil(fs, reg, 1); - break; - } - case VFALSE: case VTRUE: { - luaK_codeABC(fs, OP_LOADBOOL, reg, e->k == VTRUE, 0); - break; - } - case VK: { - luaK_codek(fs, reg, e->u.info); - break; - } - case VKFLT: { - luaK_codek(fs, reg, luaK_numberK(fs, e->u.nval)); - break; - } - case VKINT: { - luaK_codek(fs, reg, luaK_intK(fs, e->u.ival)); - break; - } - case VRELOCABLE: { - Instruction *pc = &getinstruction(fs, e); - SETARG_A(*pc, reg); /* instruction will put result in 'reg' */ - break; - } - case VNONRELOC: { - if (reg != e->u.info) - luaK_codeABC(fs, OP_MOVE, reg, e->u.info, 0); - break; - } - default: { - lua_assert(e->k == VJMP); - return; /* nothing to do... */ - } - } - e->u.info = reg; - e->k = VNONRELOC; -} - - -/* -** Ensures expression value is in any register. -*/ -static void discharge2anyreg (FuncState *fs, expdesc *e) { - if (e->k != VNONRELOC) { /* no fixed register yet? */ - luaK_reserveregs(fs, 1); /* get a register */ - discharge2reg(fs, e, fs->freereg-1); /* put value there */ - } -} - - -static int code_loadbool (FuncState *fs, int A, int b, int jump) { - luaK_getlabel(fs); /* those instructions may be jump targets */ - return luaK_codeABC(fs, OP_LOADBOOL, A, b, jump); -} - - -/* -** check whether list has any jump that do not produce a value -** or produce an inverted value -*/ -static int need_value (FuncState *fs, int list) { - for (; list != NO_JUMP; list = getjump(fs, list)) { - Instruction i = *getjumpcontrol(fs, list); - if (GET_OPCODE(i) != OP_TESTSET) return 1; - } - return 0; /* not found */ -} - - -/* -** Ensures final expression result (including results from its jump -** lists) is in register 'reg'. -** If expression has jumps, need to patch these jumps either to -** its final position or to "load" instructions (for those tests -** that do not produce values). -*/ -static void exp2reg (FuncState *fs, expdesc *e, int reg) { - discharge2reg(fs, e, reg); - if (e->k == VJMP) /* expression itself is a test? */ - luaK_concat(fs, &e->t, e->u.info); /* put this jump in 't' list */ - if (hasjumps(e)) { - int final; /* position after whole expression */ - int p_f = NO_JUMP; /* position of an eventual LOAD false */ - int p_t = NO_JUMP; /* position of an eventual LOAD true */ - if (need_value(fs, e->t) || need_value(fs, e->f)) { - int fj = (e->k == VJMP) ? NO_JUMP : luaK_jump(fs); - p_f = code_loadbool(fs, reg, 0, 1); - p_t = code_loadbool(fs, reg, 1, 0); - luaK_patchtohere(fs, fj); - } - final = luaK_getlabel(fs); - patchlistaux(fs, e->f, final, reg, p_f); - patchlistaux(fs, e->t, final, reg, p_t); - } - e->f = e->t = NO_JUMP; - e->u.info = reg; - e->k = VNONRELOC; -} - - -/* -** Ensures final expression result (including results from its jump -** lists) is in next available register. -*/ -void luaK_exp2nextreg (FuncState *fs, expdesc *e) { - luaK_dischargevars(fs, e); - freeexp(fs, e); - luaK_reserveregs(fs, 1); - exp2reg(fs, e, fs->freereg - 1); -} - - -/* -** Ensures final expression result (including results from its jump -** lists) is in some (any) register and return that register. -*/ -int luaK_exp2anyreg (FuncState *fs, expdesc *e) { - luaK_dischargevars(fs, e); - if (e->k == VNONRELOC) { /* expression already has a register? */ - if (!hasjumps(e)) /* no jumps? */ - return e->u.info; /* result is already in a register */ - if (e->u.info >= fs->nactvar) { /* reg. is not a local? */ - exp2reg(fs, e, e->u.info); /* put final result in it */ - return e->u.info; - } - } - luaK_exp2nextreg(fs, e); /* otherwise, use next available register */ - return e->u.info; -} - - -/* -** Ensures final expression result is either in a register or in an -** upvalue. -*/ -void luaK_exp2anyregup (FuncState *fs, expdesc *e) { - if (e->k != VUPVAL || hasjumps(e)) - luaK_exp2anyreg(fs, e); -} - - -/* -** Ensures final expression result is either in a register or it is -** a constant. -*/ -void luaK_exp2val (FuncState *fs, expdesc *e) { - if (hasjumps(e)) - luaK_exp2anyreg(fs, e); - else - luaK_dischargevars(fs, e); -} - - -/* -** Ensures final expression result is in a valid R/K index -** (that is, it is either in a register or in 'k' with an index -** in the range of R/K indices). -** Returns R/K index. -*/ -int luaK_exp2RK (FuncState *fs, expdesc *e) { - luaK_exp2val(fs, e); - switch (e->k) { /* move constants to 'k' */ - case VTRUE: e->u.info = boolK(fs, 1); goto vk; - case VFALSE: e->u.info = boolK(fs, 0); goto vk; - case VNIL: e->u.info = nilK(fs); goto vk; - case VKINT: e->u.info = luaK_intK(fs, e->u.ival); goto vk; - case VKFLT: e->u.info = luaK_numberK(fs, e->u.nval); goto vk; - case VK: - vk: - e->k = VK; - if (e->u.info <= MAXINDEXRK) /* constant fits in 'argC'? */ - return RKASK(e->u.info); - else break; - default: break; - } - /* not a constant in the right range: put it in a register */ - return luaK_exp2anyreg(fs, e); -} - - -/* -** Generate code to store result of expression 'ex' into variable 'var'. -*/ -void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) { - switch (var->k) { - case VLOCAL: { - freeexp(fs, ex); - exp2reg(fs, ex, var->u.info); /* compute 'ex' into proper place */ - return; - } - case VUPVAL: { - int e = luaK_exp2anyreg(fs, ex); - luaK_codeABC(fs, OP_SETUPVAL, e, var->u.info, 0); - break; - } - case VINDEXED: { - OpCode op = (var->u.ind.vt == VLOCAL) ? OP_SETTABLE : OP_SETTABUP; - int e = luaK_exp2RK(fs, ex); - luaK_codeABC(fs, op, var->u.ind.t, var->u.ind.idx, e); - break; - } - default: lua_assert(0); /* invalid var kind to store */ - } - freeexp(fs, ex); -} - - -/* -** Emit SELF instruction (convert expression 'e' into 'e:key(e,'). -*/ -void luaK_self (FuncState *fs, expdesc *e, expdesc *key) { - int ereg; - luaK_exp2anyreg(fs, e); - ereg = e->u.info; /* register where 'e' was placed */ - freeexp(fs, e); - e->u.info = fs->freereg; /* base register for op_self */ - e->k = VNONRELOC; /* self expression has a fixed register */ - luaK_reserveregs(fs, 2); /* function and 'self' produced by op_self */ - luaK_codeABC(fs, OP_SELF, e->u.info, ereg, luaK_exp2RK(fs, key)); - freeexp(fs, key); -} - - -/* -** Negate condition 'e' (where 'e' is a comparison). -*/ -static void negatecondition (FuncState *fs, expdesc *e) { - Instruction *pc = getjumpcontrol(fs, e->u.info); - lua_assert(testTMode(GET_OPCODE(*pc)) && GET_OPCODE(*pc) != OP_TESTSET && - GET_OPCODE(*pc) != OP_TEST); - SETARG_A(*pc, !(GETARG_A(*pc))); -} - - -/* -** Emit instruction to jump if 'e' is 'cond' (that is, if 'cond' -** is true, code will jump if 'e' is true.) Return jump position. -** Optimize when 'e' is 'not' something, inverting the condition -** and removing the 'not'. -*/ -static int jumponcond (FuncState *fs, expdesc *e, int cond) { - if (e->k == VRELOCABLE) { - Instruction ie = getinstruction(fs, e); - if (GET_OPCODE(ie) == OP_NOT) { - fs->pc--; /* remove previous OP_NOT */ - return condjump(fs, OP_TEST, GETARG_B(ie), 0, !cond); - } - /* else go through */ - } - discharge2anyreg(fs, e); - freeexp(fs, e); - return condjump(fs, OP_TESTSET, NO_REG, e->u.info, cond); -} - - -/* -** Emit code to go through if 'e' is true, jump otherwise. -*/ -void luaK_goiftrue (FuncState *fs, expdesc *e) { - int pc; /* pc of new jump */ - luaK_dischargevars(fs, e); - switch (e->k) { - case VJMP: { /* condition? */ - negatecondition(fs, e); /* jump when it is false */ - pc = e->u.info; /* save jump position */ - break; - } - case VK: case VKFLT: case VKINT: case VTRUE: { - pc = NO_JUMP; /* always true; do nothing */ - break; - } - default: { - pc = jumponcond(fs, e, 0); /* jump when false */ - break; - } - } - luaK_concat(fs, &e->f, pc); /* insert new jump in false list */ - luaK_patchtohere(fs, e->t); /* true list jumps to here (to go through) */ - e->t = NO_JUMP; -} - - -/* -** Emit code to go through if 'e' is false, jump otherwise. -*/ -void luaK_goiffalse (FuncState *fs, expdesc *e) { - int pc; /* pc of new jump */ - luaK_dischargevars(fs, e); - switch (e->k) { - case VJMP: { - pc = e->u.info; /* already jump if true */ - break; - } - case VNIL: case VFALSE: { - pc = NO_JUMP; /* always false; do nothing */ - break; - } - default: { - pc = jumponcond(fs, e, 1); /* jump if true */ - break; - } - } - luaK_concat(fs, &e->t, pc); /* insert new jump in 't' list */ - luaK_patchtohere(fs, e->f); /* false list jumps to here (to go through) */ - e->f = NO_JUMP; -} - - -/* -** Code 'not e', doing constant folding. -*/ -static void codenot (FuncState *fs, expdesc *e) { - luaK_dischargevars(fs, e); - switch (e->k) { - case VNIL: case VFALSE: { - e->k = VTRUE; /* true == not nil == not false */ - break; - } - case VK: case VKFLT: case VKINT: case VTRUE: { - e->k = VFALSE; /* false == not "x" == not 0.5 == not 1 == not true */ - break; - } - case VJMP: { - negatecondition(fs, e); - break; - } - case VRELOCABLE: - case VNONRELOC: { - discharge2anyreg(fs, e); - freeexp(fs, e); - e->u.info = luaK_codeABC(fs, OP_NOT, 0, e->u.info, 0); - e->k = VRELOCABLE; - break; - } - default: lua_assert(0); /* cannot happen */ - } - /* interchange true and false lists */ - { int temp = e->f; e->f = e->t; e->t = temp; } - removevalues(fs, e->f); /* values are useless when negated */ - removevalues(fs, e->t); -} - - -/* -** Create expression 't[k]'. 't' must have its final result already in a -** register or upvalue. -*/ -void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) { - lua_assert(!hasjumps(t) && (vkisinreg(t->k) || t->k == VUPVAL)); - t->u.ind.t = t->u.info; /* register or upvalue index */ - t->u.ind.idx = luaK_exp2RK(fs, k); /* R/K index for key */ - t->u.ind.vt = (t->k == VUPVAL) ? VUPVAL : VLOCAL; - t->k = VINDEXED; -} - - -/* -** Return false if folding can raise an error. -** Bitwise operations need operands convertible to integers; division -** operations cannot have 0 as divisor. -*/ -static int validop (int op, TValue *v1, TValue *v2) { - switch (op) { - case LUA_OPBAND: case LUA_OPBOR: case LUA_OPBXOR: - case LUA_OPSHL: case LUA_OPSHR: case LUA_OPBNOT: { /* conversion errors */ - lua_Integer i; - return (tointeger(v1, &i) && tointeger(v2, &i)); - } - case LUA_OPDIV: case LUA_OPIDIV: case LUA_OPMOD: /* division by 0 */ - return (nvalue(v2) != 0); - default: return 1; /* everything else is valid */ - } -} - - -/* -** Try to "constant-fold" an operation; return 1 iff successful. -** (In this case, 'e1' has the final result.) -*/ -static int constfolding (FuncState *fs, int op, expdesc *e1, - const expdesc *e2) { - TValue v1, v2, res; - if (!tonumeral(e1, &v1) || !tonumeral(e2, &v2) || !validop(op, &v1, &v2)) - return 0; /* non-numeric operands or not safe to fold */ - luaO_arith(fs->ls->L, op, &v1, &v2, &res); /* does operation */ - if (ttisinteger(&res)) { - e1->k = VKINT; - e1->u.ival = ivalue(&res); - } - else { /* folds neither NaN nor 0.0 (to avoid problems with -0.0) */ - lua_Number n = fltvalue(&res); - if (luai_numisnan(n) || n == 0) - return 0; - e1->k = VKFLT; - e1->u.nval = n; - } - return 1; -} - - -/* -** Emit code for unary expressions that "produce values" -** (everything but 'not'). -** Expression to produce final result will be encoded in 'e'. -*/ -static void codeunexpval (FuncState *fs, OpCode op, expdesc *e, int line) { - int r = luaK_exp2anyreg(fs, e); /* opcodes operate only on registers */ - freeexp(fs, e); - e->u.info = luaK_codeABC(fs, op, 0, r, 0); /* generate opcode */ - e->k = VRELOCABLE; /* all those operations are relocatable */ - luaK_fixline(fs, line); -} - - -/* -** Emit code for binary expressions that "produce values" -** (everything but logical operators 'and'/'or' and comparison -** operators). -** Expression to produce final result will be encoded in 'e1'. -** Because 'luaK_exp2RK' can free registers, its calls must be -** in "stack order" (that is, first on 'e2', which may have more -** recent registers to be released). -*/ -static void codebinexpval (FuncState *fs, OpCode op, - expdesc *e1, expdesc *e2, int line) { - int rk2 = luaK_exp2RK(fs, e2); /* both operands are "RK" */ - int rk1 = luaK_exp2RK(fs, e1); - freeexps(fs, e1, e2); - e1->u.info = luaK_codeABC(fs, op, 0, rk1, rk2); /* generate opcode */ - e1->k = VRELOCABLE; /* all those operations are relocatable */ - luaK_fixline(fs, line); -} - - -/* -** Emit code for comparisons. -** 'e1' was already put in R/K form by 'luaK_infix'. -*/ -static void codecomp (FuncState *fs, BinOpr opr, expdesc *e1, expdesc *e2) { - int rk1 = (e1->k == VK) ? RKASK(e1->u.info) - : check_exp(e1->k == VNONRELOC, e1->u.info); - int rk2 = luaK_exp2RK(fs, e2); - freeexps(fs, e1, e2); - switch (opr) { - case OPR_NE: { /* '(a ~= b)' ==> 'not (a == b)' */ - e1->u.info = condjump(fs, OP_EQ, 0, rk1, rk2); - break; - } - case OPR_GT: case OPR_GE: { - /* '(a > b)' ==> '(b < a)'; '(a >= b)' ==> '(b <= a)' */ - OpCode op = cast(OpCode, (opr - OPR_NE) + OP_EQ); - e1->u.info = condjump(fs, op, 1, rk2, rk1); /* invert operands */ - break; - } - default: { /* '==', '<', '<=' use their own opcodes */ - OpCode op = cast(OpCode, (opr - OPR_EQ) + OP_EQ); - e1->u.info = condjump(fs, op, 1, rk1, rk2); - break; - } - } - e1->k = VJMP; -} - - -/* -** Aplly prefix operation 'op' to expression 'e'. -*/ -void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e, int line) { - static const expdesc ef = {VKINT, {0}, NO_JUMP, NO_JUMP}; - switch (op) { - case OPR_MINUS: case OPR_BNOT: /* use 'ef' as fake 2nd operand */ - if (constfolding(fs, op + LUA_OPUNM, e, &ef)) - break; - /* FALLTHROUGH */ - case OPR_LEN: - codeunexpval(fs, cast(OpCode, op + OP_UNM), e, line); - break; - case OPR_NOT: codenot(fs, e); break; - default: lua_assert(0); - } -} - - -/* -** Process 1st operand 'v' of binary operation 'op' before reading -** 2nd operand. -*/ -void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) { - switch (op) { - case OPR_AND: { - luaK_goiftrue(fs, v); /* go ahead only if 'v' is true */ - break; - } - case OPR_OR: { - luaK_goiffalse(fs, v); /* go ahead only if 'v' is false */ - break; - } - case OPR_CONCAT: { - luaK_exp2nextreg(fs, v); /* operand must be on the 'stack' */ - break; - } - case OPR_ADD: case OPR_SUB: - case OPR_MUL: case OPR_DIV: case OPR_IDIV: - case OPR_MOD: case OPR_POW: - case OPR_BAND: case OPR_BOR: case OPR_BXOR: - case OPR_SHL: case OPR_SHR: { - if (!tonumeral(v, NULL)) - luaK_exp2RK(fs, v); - /* else keep numeral, which may be folded with 2nd operand */ - break; - } - default: { - luaK_exp2RK(fs, v); - break; - } - } -} - - -/* -** Finalize code for binary operation, after reading 2nd operand. -** For '(a .. b .. c)' (which is '(a .. (b .. c))', because -** concatenation is right associative), merge second CONCAT into first -** one. -*/ -void luaK_posfix (FuncState *fs, BinOpr op, - expdesc *e1, expdesc *e2, int line) { - switch (op) { - case OPR_AND: { - lua_assert(e1->t == NO_JUMP); /* list closed by 'luK_infix' */ - luaK_dischargevars(fs, e2); - luaK_concat(fs, &e2->f, e1->f); - *e1 = *e2; - break; - } - case OPR_OR: { - lua_assert(e1->f == NO_JUMP); /* list closed by 'luK_infix' */ - luaK_dischargevars(fs, e2); - luaK_concat(fs, &e2->t, e1->t); - *e1 = *e2; - break; - } - case OPR_CONCAT: { - luaK_exp2val(fs, e2); - if (e2->k == VRELOCABLE && - GET_OPCODE(getinstruction(fs, e2)) == OP_CONCAT) { - lua_assert(e1->u.info == GETARG_B(getinstruction(fs, e2))-1); - freeexp(fs, e1); - SETARG_B(getinstruction(fs, e2), e1->u.info); - e1->k = VRELOCABLE; e1->u.info = e2->u.info; - } - else { - luaK_exp2nextreg(fs, e2); /* operand must be on the 'stack' */ - codebinexpval(fs, OP_CONCAT, e1, e2, line); - } - break; - } - case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV: - case OPR_IDIV: case OPR_MOD: case OPR_POW: - case OPR_BAND: case OPR_BOR: case OPR_BXOR: - case OPR_SHL: case OPR_SHR: { - if (!constfolding(fs, op + LUA_OPADD, e1, e2)) - codebinexpval(fs, cast(OpCode, op + OP_ADD), e1, e2, line); - break; - } - case OPR_EQ: case OPR_LT: case OPR_LE: - case OPR_NE: case OPR_GT: case OPR_GE: { - codecomp(fs, op, e1, e2); - break; - } - default: lua_assert(0); - } -} - - -/* -** Change line information associated with current position. -*/ -void luaK_fixline (FuncState *fs, int line) { - fs->f->lineinfo[fs->pc - 1] = line; -} - - -/* -** Emit a SETLIST instruction. -** 'base' is register that keeps table; -** 'nelems' is #table plus those to be stored now; -** 'tostore' is number of values (in registers 'base + 1',...) to add to -** table (or LUA_MULTRET to add up to stack top). -*/ -void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) { - int c = (nelems - 1)/LFIELDS_PER_FLUSH + 1; - int b = (tostore == LUA_MULTRET) ? 0 : tostore; - lua_assert(tostore != 0 && tostore <= LFIELDS_PER_FLUSH); - if (c <= MAXARG_C) - luaK_codeABC(fs, OP_SETLIST, base, b, c); - else if (c <= MAXARG_Ax) { - luaK_codeABC(fs, OP_SETLIST, base, b, 0); - codeextraarg(fs, c); - } - else - luaX_syntaxerror(fs->ls, "constructor too long"); - fs->freereg = base + 1; /* free registers with list values */ -} - |