diff --git a/ldebug.c b/ldebug.c index afdc2b74..0c4439c1 100644 --- a/ldebug.c +++ b/ldebug.c @@ -33,10 +33,8 @@ #define noLuaClosure(f) ((f) == NULL || (f)->c.tt == LUA_VCCL) - -/* Active Lua function (given call info) */ -#define ci_func(ci) (clLvalue(s2v((ci)->func))) - +/* inverse of 'pcRel' */ +#define invpcRel(pc, p) ((p)->code + (pc) + 1) static const char *funcnamefromcode (lua_State *L, CallInfo *ci, const char **name); @@ -127,20 +125,18 @@ static void settraps (CallInfo *ci) { /* ** This function can be called during a signal, under "reasonable" ** assumptions. -** Fields 'oldpc', 'basehookcount', and 'hookcount' (set by -** 'resethookcount') are for debug only, and it is no problem if they -** get arbitrary values (causes at most one wrong hook call). 'hookmask' -** is an atomic value. We assume that pointers are atomic too (e.g., gcc -** ensures that for all platforms where it runs). Moreover, 'hook' is -** always checked before being called (see 'luaD_hook'). +** Fields 'basehookcount' and 'hookcount' (set by 'resethookcount') +** are for debug only, and it is no problem if they get arbitrary +** values (causes at most one wrong hook call). 'hookmask' is an atomic +** value. We assume that pointers are atomic too (e.g., gcc ensures that +** for all platforms where it runs). Moreover, 'hook' is always checked +** before being called (see 'luaD_hook'). */ LUA_API void lua_sethook (lua_State *L, lua_Hook func, int mask, int count) { if (func == NULL || mask == 0) { /* turn off hooks? */ mask = 0; func = NULL; } - if (isLua(L->ci)) - L->oldpc = L->ci->u.l.savedpc; L->hook = func; L->basehookcount = count; resethookcount(L); @@ -795,10 +791,24 @@ static int changedline (const Proto *p, int oldpc, int newpc) { } +/* +** Traces the execution of a Lua function. Called before the execution +** of each opcode, when debug is on. 'L->oldpc' stores the last +** instruction traced, to detect line changes. When entering a new +** function, 'npci' will be zero and will test as a new line without +** the need for 'oldpc'; so, 'oldpc' does not need to be initialized +** before. Some exceptional conditions may return to a function without +** updating 'oldpc'. In that case, 'oldpc' may be invalid; if so, it is +** reset to zero. (A wrong but valid 'oldpc' at most causes an extra +** call to a line hook.) +*/ int luaG_traceexec (lua_State *L, const Instruction *pc) { CallInfo *ci = L->ci; lu_byte mask = L->hookmask; + const Proto *p = ci_func(ci)->p; int counthook; + /* 'L->oldpc' may be invalid; reset it in this case */ + int oldpc = (L->oldpc < p->sizecode) ? L->oldpc : 0; if (!(mask & (LUA_MASKLINE | LUA_MASKCOUNT))) { /* no hooks? */ ci->u.l.trap = 0; /* don't need to stop again */ return 0; /* turn off 'trap' */ @@ -819,15 +829,14 @@ int luaG_traceexec (lua_State *L, const Instruction *pc) { if (counthook) luaD_hook(L, LUA_HOOKCOUNT, -1, 0, 0); /* call count hook */ if (mask & LUA_MASKLINE) { - const Proto *p = ci_func(ci)->p; int npci = pcRel(pc, p); if (npci == 0 || /* call linehook when enter a new function, */ - pc <= L->oldpc || /* when jump back (loop), or when */ - changedline(p, pcRel(L->oldpc, p), npci)) { /* enter new line */ + pc <= invpcRel(oldpc, p) || /* when jump back (loop), or when */ + changedline(p, oldpc, npci)) { /* enter new line */ int newline = luaG_getfuncline(p, npci); luaD_hook(L, LUA_HOOKLINE, newline, 0, 0); /* call line hook */ } - L->oldpc = pc; /* 'pc' of last call to line hook */ + L->oldpc = npci; /* 'pc' of last call to line hook */ } if (L->status == LUA_YIELD) { /* did hook yield? */ if (counthook) diff --git a/ldebug.h b/ldebug.h index 1fe0efab..a0a58486 100644 --- a/ldebug.h +++ b/ldebug.h @@ -13,6 +13,11 @@ #define pcRel(pc, p) (cast_int((pc) - (p)->code) - 1) + +/* Active Lua function (given call info) */ +#define ci_func(ci) (clLvalue(s2v((ci)->func))) + + #define resethookcount(L) (L->hookcount = L->basehookcount) /* diff --git a/ldo.c b/ldo.c index 4c976a14..98dd9fbb 100644 --- a/ldo.c +++ b/ldo.c @@ -327,7 +327,7 @@ static StkId rethook (lua_State *L, CallInfo *ci, StkId firstres, int nres) { ptrdiff_t oldtop = savestack(L, L->top); /* hook may change top */ int delta = 0; if (isLuacode(ci)) { - Proto *p = clLvalue(s2v(ci->func))->p; + Proto *p = ci_func(ci)->p; if (p->is_vararg) delta = ci->u.l.nextraargs + p->numparams + 1; if (L->top < ci->top) @@ -340,8 +340,8 @@ static StkId rethook (lua_State *L, CallInfo *ci, StkId firstres, int nres) { luaD_hook(L, LUA_HOOKRET, -1, ftransfer, nres); /* call it */ ci->func -= delta; } - if (isLua(ci->previous)) - L->oldpc = ci->previous->u.l.savedpc; /* update 'oldpc' */ + if (isLua(ci = ci->previous)) + L->oldpc = pcRel(ci->u.l.savedpc, ci_func(ci)->p); /* update 'oldpc' */ return restorestack(L, oldtop); } diff --git a/lstate.c b/lstate.c index 28853dc7..06fa13d7 100644 --- a/lstate.c +++ b/lstate.c @@ -301,6 +301,7 @@ static void preinit_thread (lua_State *L, global_State *g) { L->openupval = NULL; L->status = LUA_OK; L->errfunc = 0; + L->oldpc = 0; } diff --git a/lstate.h b/lstate.h index 2e8bd6c4..0c545ec5 100644 --- a/lstate.h +++ b/lstate.h @@ -286,7 +286,6 @@ struct lua_State { StkId top; /* first free slot in the stack */ global_State *l_G; CallInfo *ci; /* call info for current function */ - const Instruction *oldpc; /* last pc traced */ StkId stack_last; /* last free slot in the stack */ StkId stack; /* stack base */ UpVal *openupval; /* list of open upvalues in this stack */ @@ -297,6 +296,7 @@ struct lua_State { volatile lua_Hook hook; ptrdiff_t errfunc; /* current error handling function (stack index) */ l_uint32 nCcalls; /* number of allowed nested C calls - 'nci' */ + int oldpc; /* last pc traced */ int stacksize; int basehookcount; int hookcount; diff --git a/lvm.c b/lvm.c index 66d451b0..08681af1 100644 --- a/lvm.c +++ b/lvm.c @@ -1794,7 +1794,7 @@ void luaV_execute (lua_State *L, CallInfo *ci) { ProtectNT(luaT_adjustvarargs(L, GETARG_A(i), ci, cl->p)); if (trap) { luaD_hookcall(L, ci); - L->oldpc = pc + 1; /* next opcode will be seen as a "new" line */ + L->oldpc = 1; /* next opcode will be seen as a "new" line */ } updatebase(ci); /* function has new base after adjustment */ vmbreak;