Stack indices changed to union's

That will allow to change pointers to offsets while reallocating
the stack.

1 files changed, 62 insertions, 63 deletions

diff --git a/ldo.c b/ldo.c
index 419b3db9..d45c74da 100644
--- a/ldo.c
+++ b/ldo.c
@@ -104,11 +104,11 @@ void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) {
     }
     default: {
       lua_assert(errorstatus(errcode));  /* real error */
-      setobjs2s(L, oldtop, L->top - 1);  /* error message on current top */
+      setobjs2s(L, oldtop, L->top.p - 1);  /* error message on current top */
       break;
     }
   }
-  L->top = oldtop + 1;
+  L->top.p = oldtop + 1;
 }
 
 
@@ -121,7 +121,7 @@ l_noret luaD_throw (lua_State *L, int errcode) {
     global_State *g = G(L);
     errcode = luaE_resetthread(L, errcode);  /* close all upvalues */
     if (g->mainthread->errorJmp) {  /* main thread has a handler? */
-      setobjs2s(L, g->mainthread->top++, L->top - 1);  /* copy error obj. */
+      setobjs2s(L, g->mainthread->top.p++, L->top.p - 1);  /* copy error obj. */
       luaD_throw(g->mainthread, errcode);  /* re-throw in main thread */
     }
     else {  /* no handler at all; abort */
@@ -160,13 +160,13 @@ int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
 static void correctstack (lua_State *L, StkId oldstack, StkId newstack) {
   CallInfo *ci;
   UpVal *up;
-  L->top = (L->top - oldstack) + newstack;
-  L->tbclist = (L->tbclist - oldstack) + newstack;
+  L->top.p = (L->top.p - oldstack) + newstack;
+  L->tbclist.p = (L->tbclist.p - oldstack) + newstack;
   for (up = L->openupval; up != NULL; up = up->u.open.next)
-    up->v = s2v((uplevel(up) - oldstack) + newstack);
+    up->v.p = s2v((uplevel(up) - oldstack) + newstack);
   for (ci = L->ci; ci != NULL; ci = ci->previous) {
-    ci->top = (ci->top - oldstack) + newstack;
-    ci->func = (ci->func - oldstack) + newstack;
+    ci->top.p = (ci->top.p - oldstack) + newstack;
+    ci->func.p = (ci->func.p - oldstack) + newstack;
     if (isLua(ci))
       ci->u.l.trap = 1;  /* signal to update 'trap' in 'luaV_execute' */
   }
@@ -176,7 +176,6 @@ static void correctstack (lua_State *L, StkId oldstack, StkId newstack) {
 /* some space for error handling */
 #define ERRORSTACKSIZE  (LUAI_MAXSTACK + 200)
 
-
 /*
 ** Reallocate the stack to a new size, correcting all pointers into
 ** it. (There are pointers to a stack from its upvalues, from its list
@@ -201,13 +200,13 @@ int luaD_reallocstack (lua_State *L, int newsize, int raiseerror) {
   }
   /* number of elements to be copied to the new stack */
   i = ((oldsize <= newsize) ? oldsize : newsize) + EXTRA_STACK;
-  memcpy(newstack, L->stack, i * sizeof(StackValue));
+  memcpy(newstack, L->stack.p, i * sizeof(StackValue));
   for (; i < newsize + EXTRA_STACK; i++)
     setnilvalue(s2v(newstack + i)); /* erase new segment */
-  correctstack(L, L->stack, newstack);
-  luaM_freearray(L, L->stack, oldsize + EXTRA_STACK);
-  L->stack = newstack;
-  L->stack_last = L->stack + newsize;
+  correctstack(L, L->stack.p, newstack);
+  luaM_freearray(L, L->stack.p, oldsize + EXTRA_STACK);
+  L->stack.p = newstack;
+  L->stack_last.p = L->stack.p + newsize;
   return 1;
 }
 
@@ -229,7 +228,7 @@ int luaD_growstack (lua_State *L, int n, int raiseerror) {
   }
   else if (n < LUAI_MAXSTACK) {  /* avoids arithmetic overflows */
     int newsize = 2 * size;  /* tentative new size */
-    int needed = cast_int(L->top - L->stack) + n;
+    int needed = cast_int(L->top.p - L->stack.p) + n;
     if (newsize > LUAI_MAXSTACK)  /* cannot cross the limit */
       newsize = LUAI_MAXSTACK;
     if (newsize < needed)  /* but must respect what was asked for */
@@ -253,12 +252,12 @@ int luaD_growstack (lua_State *L, int n, int raiseerror) {
 static int stackinuse (lua_State *L) {
   CallInfo *ci;
   int res;
-  StkId lim = L->top;
+  StkId lim = L->top.p;
   for (ci = L->ci; ci != NULL; ci = ci->previous) {
-    if (lim < ci->top) lim = ci->top;
+    if (lim < ci->top.p) lim = ci->top.p;
   }
-  lua_assert(lim <= L->stack_last + EXTRA_STACK);
-  res = cast_int(lim - L->stack) + 1;  /* part of stack in use */
+  lua_assert(lim <= L->stack_last.p + EXTRA_STACK);
+  res = cast_int(lim - L->stack.p) + 1;  /* part of stack in use */
   if (res < LUA_MINSTACK)
     res = LUA_MINSTACK;  /* ensure a minimum size */
   return res;
@@ -295,7 +294,7 @@ void luaD_shrinkstack (lua_State *L) {
 
 void luaD_inctop (lua_State *L) {
   luaD_checkstack(L, 1);
-  L->top++;
+  L->top.p++;
 }
 
 /* }================================================================== */
@@ -312,8 +311,8 @@ void luaD_hook (lua_State *L, int event, int line,
   if (hook && L->allowhook) {  /* make sure there is a hook */
     int mask = CIST_HOOKED;
     CallInfo *ci = L->ci;
-    ptrdiff_t top = savestack(L, L->top);  /* preserve original 'top' */
-    ptrdiff_t ci_top = savestack(L, ci->top);  /* idem for 'ci->top' */
+    ptrdiff_t top = savestack(L, L->top.p);  /* preserve original 'top' */
+    ptrdiff_t ci_top = savestack(L, ci->top.p);  /* idem for 'ci->top' */
     lua_Debug ar;
     ar.event = event;
     ar.currentline = line;
@@ -323,11 +322,11 @@ void luaD_hook (lua_State *L, int event, int line,
       ci->u2.transferinfo.ftransfer = ftransfer;
       ci->u2.transferinfo.ntransfer = ntransfer;
     }
-    if (isLua(ci) && L->top < ci->top)
-      L->top = ci->top;  /* protect entire activation register */
+    if (isLua(ci) && L->top.p < ci->top.p)
+      L->top.p = ci->top.p;  /* protect entire activation register */
     luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
-    if (ci->top < L->top + LUA_MINSTACK)
-      ci->top = L->top + LUA_MINSTACK;
+    if (ci->top.p < L->top.p + LUA_MINSTACK)
+      ci->top.p = L->top.p + LUA_MINSTACK;
     L->allowhook = 0;  /* cannot call hooks inside a hook */
     ci->callstatus |= mask;
     lua_unlock(L);
@@ -335,8 +334,8 @@ void luaD_hook (lua_State *L, int event, int line,
     lua_lock(L);
     lua_assert(!L->allowhook);
     L->allowhook = 1;
-    ci->top = restorestack(L, ci_top);
-    L->top = restorestack(L, top);
+    ci->top.p = restorestack(L, ci_top);
+    L->top.p = restorestack(L, top);
     ci->callstatus &= ~mask;
   }
 }
@@ -367,7 +366,7 @@ void luaD_hookcall (lua_State *L, CallInfo *ci) {
 */
 static void rethook (lua_State *L, CallInfo *ci, int nres) {
   if (L->hookmask & LUA_MASKRET) {  /* is return hook on? */
-    StkId firstres = L->top - nres;  /* index of first result */
+    StkId firstres = L->top.p - nres;  /* index of first result */
     int delta = 0;  /* correction for vararg functions */
     int ftransfer;
     if (isLua(ci)) {
@@ -375,10 +374,10 @@ static void rethook (lua_State *L, CallInfo *ci, int nres) {
       if (p->is_vararg)
         delta = ci->u.l.nextraargs + p->numparams + 1;
     }
-    ci->func += delta;  /* if vararg, back to virtual 'func' */
-    ftransfer = cast(unsigned short, firstres - ci->func);
+    ci->func.p += delta;  /* if vararg, back to virtual 'func' */
+    ftransfer = cast(unsigned short, firstres - ci->func.p);
     luaD_hook(L, LUA_HOOKRET, -1, ftransfer, nres);  /* call it */
-    ci->func -= delta;
+    ci->func.p -= delta;
   }
   if (isLua(ci = ci->previous))
     L->oldpc = pcRel(ci->u.l.savedpc, ci_func(ci)->p);  /* set 'oldpc' */
@@ -397,9 +396,9 @@ StkId luaD_tryfuncTM (lua_State *L, StkId func) {
   tm = luaT_gettmbyobj(L, s2v(func), TM_CALL);  /* (after previous GC) */
   if (l_unlikely(ttisnil(tm)))
     luaG_callerror(L, s2v(func));  /* nothing to call */
-  for (p = L->top; p > func; p--)  /* open space for metamethod */
+  for (p = L->top.p; p > func; p--)  /* open space for metamethod */
     setobjs2s(L, p, p-1);
-  L->top++;  /* stack space pre-allocated by the caller */
+  L->top.p++;  /* stack space pre-allocated by the caller */
   setobj2s(L, func, tm);  /* metamethod is the new function to be called */
   return func;
 }
@@ -416,14 +415,14 @@ l_sinline void moveresults (lua_State *L, StkId res, int nres, int wanted) {
   int i;
   switch (wanted) {  /* handle typical cases separately */
     case 0:  /* no values needed */
-      L->top = res;
+      L->top.p = res;
       return;
     case 1:  /* one value needed */
       if (nres == 0)   /* no results? */
         setnilvalue(s2v(res));  /* adjust with nil */
       else  /* at least one result */
-        setobjs2s(L, res, L->top - nres);  /* move it to proper place */
-      L->top = res + 1;
+        setobjs2s(L, res, L->top.p - nres);  /* move it to proper place */
+      L->top.p = res + 1;
       return;
     case LUA_MULTRET:
       wanted = nres;  /* we want all results */
@@ -446,14 +445,14 @@ l_sinline void moveresults (lua_State *L, StkId res, int nres, int wanted) {
       break;
   }
   /* generic case */
-  firstresult = L->top - nres;  /* index of first result */
+  firstresult = L->top.p - nres;  /* index of first result */
   if (nres > wanted)  /* extra results? */
     nres = wanted;  /* don't need them */
   for (i = 0; i < nres; i++)  /* move all results to correct place */
     setobjs2s(L, res + i, firstresult + i);
   for (; i < wanted; i++)  /* complete wanted number of results */
     setnilvalue(s2v(res + i));
-  L->top = res + wanted;  /* top points after the last result */
+  L->top.p = res + wanted;  /* top points after the last result */
 }
 
 
@@ -468,7 +467,7 @@ void luaD_poscall (lua_State *L, CallInfo *ci, int nres) {
   if (l_unlikely(L->hookmask && !hastocloseCfunc(wanted)))
     rethook(L, ci, nres);
   /* move results to proper place */
-  moveresults(L, ci->func, nres, wanted);
+  moveresults(L, ci->func.p, nres, wanted);
   /* function cannot be in any of these cases when returning */
   lua_assert(!(ci->callstatus &
         (CIST_HOOKED | CIST_YPCALL | CIST_FIN | CIST_TRAN | CIST_CLSRET)));
@@ -483,10 +482,10 @@ void luaD_poscall (lua_State *L, CallInfo *ci, int nres) {
 l_sinline CallInfo *prepCallInfo (lua_State *L, StkId func, int nret,
                                                 int mask, StkId top) {
   CallInfo *ci = L->ci = next_ci(L);  /* new frame */
-  ci->func = func;
+  ci->func.p = func;
   ci->nresults = nret;
   ci->callstatus = mask;
-  ci->top = top;
+  ci->top.p = top;
   return ci;
 }
 
@@ -500,10 +499,10 @@ l_sinline int precallC (lua_State *L, StkId func, int nresults,
   CallInfo *ci;
   checkstackGCp(L, LUA_MINSTACK, func);  /* ensure minimum stack size */
   L->ci = ci = prepCallInfo(L, func, nresults, CIST_C,
-                               L->top + LUA_MINSTACK);
-  lua_assert(ci->top <= L->stack_last);
+                               L->top.p + LUA_MINSTACK);
+  lua_assert(ci->top.p <= L->stack_last.p);
   if (l_unlikely(L->hookmask & LUA_MASKCALL)) {
-    int narg = cast_int(L->top - func) - 1;
+    int narg = cast_int(L->top.p - func) - 1;
     luaD_hook(L, LUA_HOOKCALL, -1, 1, narg);
   }
   lua_unlock(L);
@@ -535,17 +534,17 @@ int luaD_pretailcall (lua_State *L, CallInfo *ci, StkId func,
       int nfixparams = p->numparams;
       int i;
       checkstackGCp(L, fsize - delta, func);
-      ci->func -= delta;  /* restore 'func' (if vararg) */
+      ci->func.p -= delta;  /* restore 'func' (if vararg) */
       for (i = 0; i < narg1; i++)  /* move down function and arguments */
-        setobjs2s(L, ci->func + i, func + i);
-      func = ci->func;  /* moved-down function */
+        setobjs2s(L, ci->func.p + i, func + i);
+      func = ci->func.p;  /* moved-down function */
       for (; narg1 <= nfixparams; narg1++)
         setnilvalue(s2v(func + narg1));  /* complete missing arguments */
-      ci->top = func + 1 + fsize;  /* top for new function */
-      lua_assert(ci->top <= L->stack_last);
+      ci->top.p = func + 1 + fsize;  /* top for new function */
+      lua_assert(ci->top.p <= L->stack_last.p);
       ci->u.l.savedpc = p->code;  /* starting point */
       ci->callstatus |= CIST_TAIL;
-      L->top = func + narg1;  /* set top */
+      L->top.p = func + narg1;  /* set top */
       return -1;
     }
     default: {  /* not a function */
@@ -578,15 +577,15 @@ CallInfo *luaD_precall (lua_State *L, StkId func, int nresults) {
     case LUA_VLCL: {  /* Lua function */
       CallInfo *ci;
       Proto *p = clLvalue(s2v(func))->p;
-      int narg = cast_int(L->top - func) - 1;  /* number of real arguments */
+      int narg = cast_int(L->top.p - func) - 1;  /* number of real arguments */
       int nfixparams = p->numparams;
       int fsize = p->maxstacksize;  /* frame size */
       checkstackGCp(L, fsize, func);
       L->ci = ci = prepCallInfo(L, func, nresults, 0, func + 1 + fsize);
       ci->u.l.savedpc = p->code;  /* starting point */
       for (; narg < nfixparams; narg++)
-        setnilvalue(s2v(L->top++));  /* complete missing arguments */
-      lua_assert(ci->top <= L->stack_last);
+        setnilvalue(s2v(L->top.p++));  /* complete missing arguments */
+      lua_assert(ci->top.p <= L->stack_last.p);
       return ci;
     }
     default: {  /* not a function */
@@ -748,8 +747,8 @@ static CallInfo *findpcall (lua_State *L) {
 ** coroutine error handler and should not kill the coroutine.)
 */
 static int resume_error (lua_State *L, const char *msg, int narg) {
-  L->top -= narg;  /* remove args from the stack */
-  setsvalue2s(L, L->top, luaS_new(L, msg));  /* push error message */
+  L->top.p -= narg;  /* remove args from the stack */
+  setsvalue2s(L, L->top.p, luaS_new(L, msg));  /* push error message */
   api_incr_top(L);
   lua_unlock(L);
   return LUA_ERRRUN;
@@ -765,7 +764,7 @@ static int resume_error (lua_State *L, const char *msg, int narg) {
 */
 static void resume (lua_State *L, void *ud) {
   int n = *(cast(int*, ud));  /* number of arguments */
-  StkId firstArg = L->top - n;  /* first argument */
+  StkId firstArg = L->top.p - n;  /* first argument */
   CallInfo *ci = L->ci;
   if (L->status == LUA_OK)  /* starting a coroutine? */
     ccall(L, firstArg - 1, LUA_MULTRET, 0);  /* just call its body */
@@ -773,7 +772,7 @@ static void resume (lua_State *L, void *ud) {
     lua_assert(L->status == LUA_YIELD);
     L->status = LUA_OK;  /* mark that it is running (again) */
     if (isLua(ci)) {  /* yielded inside a hook? */
-      L->top = firstArg;  /* discard arguments */
+      L->top.p = firstArg;  /* discard arguments */
       luaV_execute(L, ci);  /* just continue running Lua code */
     }
     else {  /* 'common' yield */
@@ -816,7 +815,7 @@ LUA_API int lua_resume (lua_State *L, lua_State *from, int nargs,
   if (L->status == LUA_OK) {  /* may be starting a coroutine */
     if (L->ci != &L->base_ci)  /* not in base level? */
       return resume_error(L, "cannot resume non-suspended coroutine", nargs);
-    else if (L->top - (L->ci->func + 1) == nargs)  /* no function? */
+    else if (L->top.p - (L->ci->func.p + 1) == nargs)  /* no function? */
       return resume_error(L, "cannot resume dead coroutine", nargs);
   }
   else if (L->status != LUA_YIELD)  /* ended with errors? */
@@ -834,11 +833,11 @@ LUA_API int lua_resume (lua_State *L, lua_State *from, int nargs,
     lua_assert(status == L->status);  /* normal end or yield */
   else {  /* unrecoverable error */
     L->status = cast_byte(status);  /* mark thread as 'dead' */
-    luaD_seterrorobj(L, status, L->top);  /* push error message */
-    L->ci->top = L->top;
+    luaD_seterrorobj(L, status, L->top.p);  /* push error message */
+    L->ci->top.p = L->top.p;
   }
   *nresults = (status == LUA_YIELD) ? L->ci->u2.nyield
-                                    : cast_int(L->top - (L->ci->func + 1));
+                                    : cast_int(L->top.p - (L->ci->func.p + 1));
   lua_unlock(L);
   return status;
 }
@@ -993,7 +992,7 @@ int luaD_protectedparser (lua_State *L, ZIO *z, const char *name,
   p.dyd.gt.arr = NULL; p.dyd.gt.size = 0;
   p.dyd.label.arr = NULL; p.dyd.label.size = 0;
   luaZ_initbuffer(L, &p.buff);
-  status = luaD_pcall(L, f_parser, &p, savestack(L, L->top), L->errfunc);
+  status = luaD_pcall(L, f_parser, &p, savestack(L, L->top.p), L->errfunc);
   luaZ_freebuffer(L, &p.buff);
   luaM_freearray(L, p.dyd.actvar.arr, p.dyd.actvar.size);
   luaM_freearray(L, p.dyd.gt.arr, p.dyd.gt.size);