static const char *getobjname (Proto *p, int lastpc, int reg, const char **name) { int pc; *name = luaF_getlocalname(p, reg + 1, lastpc); if (*name) /* is a local? */ return "local"; /* else try symbolic execution */ pc = findsetreg(p, lastpc, reg); if (pc != -1) { /* could find instruction? */ Instruction i = p->code[pc]; OpCode op = GET_OPCODE(i); switch (op) { case OP_MOVE: { int b = GETARG_B(i); /* move from 'b' to 'a' */ if (b < GETARG_A(i)) return getobjname(p, pc, b, name); /* get name for 'b' */ break; } case OP_GETTABUP: case OP_GETTABLE: { int k = GETARG_C(i); /* key index */ int t = GETARG_B(i); /* table index */ const char *vn = (op == OP_GETTABLE) /* name of indexed variable */ ? luaF_getlocalname(p, t + 1, pc) : upvalname(p, t); kname(p, pc, k, name); return (vn && strcmp(vn, LUA_ENV) == 0) ? "global" : "field"; } case OP_GETUPVAL: { *name = upvalname(p, GETARG_B(i)); return "upvalue"; } case OP_LOADK: case OP_LOADKX: { int b = (op == OP_LOADK) ? GETARG_Bx(i) : GETARG_Ax(p->code[pc + 1]); if (ttisstring(&p->k[b])) { *name = svalue(&p->k[b]); return "constant"; } break; } case OP_SELF: { int k = GETARG_C(i); /* key index */ kname(p, pc, k, name); return "method"; } default: break; /* go through to return NULL */ } } return NULL; /* could not find reasonable name */ }
static const char *getupvalname (CallInfo *ci, const TValue *o, const char **name) { LClosure *c = ci_func(ci); int i; for (i = 0; i < c->nupvalues; i++) { if (c->upvals[i]->v == o) { *name = upvalname(c->p, i); return "upvalue"; } } return NULL; }