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'moveresults' and 'luaD_poscall' moved up in the file

pull/9/head
Roberto Ierusalimschy 8 years ago
parent
commit
24f6e236a3
  1. 134
      ldo.c

134
ldo.c

@ -1,5 +1,5 @@
/*
** $Id: ldo.c,v 2.155 2016/09/08 16:36:26 roberto Exp roberto $
** $Id: ldo.c,v 2.156 2016/09/20 16:37:45 roberto Exp roberto $
** Stack and Call structure of Lua
** See Copyright Notice in lua.h
*/
@ -325,6 +325,72 @@ static void tryfuncTM (lua_State *L, StkId func) {
}
/*
** Given 'nres' results at 'firstResult', move 'wanted' of them to 'res'.
** Handle most typical cases (zero results for commands, one result for
** expressions, multiple results for tail calls/single parameters)
** separated.
*/
static int moveresults (lua_State *L, const TValue *firstResult, StkId res,
int nres, int wanted) {
switch (wanted) { /* handle typical cases separately */
case 0: break; /* nothing to move */
case 1: { /* one result needed */
if (nres == 0) /* no results? */
firstResult = luaO_nilobject; /* adjust with nil */
setobjs2s(L, res, firstResult); /* move it to proper place */
break;
}
case LUA_MULTRET: {
int i;
for (i = 0; i < nres; i++) /* move all results to correct place */
setobjs2s(L, res + i, firstResult + i);
L->top = res + nres;
return 0; /* wanted == LUA_MULTRET */
}
default: {
int i;
if (wanted <= nres) { /* enough results? */
for (i = 0; i < wanted; i++) /* move wanted results to correct place */
setobjs2s(L, res + i, firstResult + i);
}
else { /* not enough results; use all of them plus nils */
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(res + i);
}
break;
}
}
L->top = res + wanted; /* top points after the last result */
return 1;
}
/*
** Finishes a function call: calls hook if necessary, removes CallInfo,
** moves current number of results to proper place; returns 0 iff call
** wanted multiple (variable number of) results.
*/
int luaD_poscall (lua_State *L, CallInfo *ci, StkId firstResult, int nres) {
StkId res;
int wanted = ci->nresults;
if (L->hookmask & (LUA_MASKRET | LUA_MASKLINE)) {
if (L->hookmask & LUA_MASKRET) {
ptrdiff_t fr = savestack(L, firstResult); /* hook may change stack */
luaD_hook(L, LUA_HOOKRET, -1);
firstResult = restorestack(L, fr);
}
L->oldpc = ci->previous->u.l.savedpc; /* 'oldpc' for caller function */
}
res = ci->func; /* res == final position of 1st result */
L->ci = ci->previous; /* back to caller */
/* move results to proper place */
return moveresults(L, firstResult, res, nres, wanted);
}
#define next_ci(L) (L->ci = (L->ci->next ? L->ci->next : luaE_extendCI(L)))
@ -405,72 +471,6 @@ int luaD_precall (lua_State *L, StkId func, int nresults) {
}
/*
** Given 'nres' results at 'firstResult', move 'wanted' of them to 'res'.
** Handle most typical cases (zero results for commands, one result for
** expressions, multiple results for tail calls/single parameters)
** separated.
*/
static int moveresults (lua_State *L, const TValue *firstResult, StkId res,
int nres, int wanted) {
switch (wanted) { /* handle typical cases separately */
case 0: break; /* nothing to move */
case 1: { /* one result needed */
if (nres == 0) /* no results? */
firstResult = luaO_nilobject; /* adjust with nil */
setobjs2s(L, res, firstResult); /* move it to proper place */
break;
}
case LUA_MULTRET: {
int i;
for (i = 0; i < nres; i++) /* move all results to correct place */
setobjs2s(L, res + i, firstResult + i);
L->top = res + nres;
return 0; /* wanted == LUA_MULTRET */
}
default: {
int i;
if (wanted <= nres) { /* enough results? */
for (i = 0; i < wanted; i++) /* move wanted results to correct place */
setobjs2s(L, res + i, firstResult + i);
}
else { /* not enough results; use all of them plus nils */
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(res + i);
}
break;
}
}
L->top = res + wanted; /* top points after the last result */
return 1;
}
/*
** Finishes a function call: calls hook if necessary, removes CallInfo,
** moves current number of results to proper place; returns 0 iff call
** wanted multiple (variable number of) results.
*/
int luaD_poscall (lua_State *L, CallInfo *ci, StkId firstResult, int nres) {
StkId res;
int wanted = ci->nresults;
if (L->hookmask & (LUA_MASKRET | LUA_MASKLINE)) {
if (L->hookmask & LUA_MASKRET) {
ptrdiff_t fr = savestack(L, firstResult); /* hook may change stack */
luaD_hook(L, LUA_HOOKRET, -1);
firstResult = restorestack(L, fr);
}
L->oldpc = ci->previous->u.l.savedpc; /* 'oldpc' for caller function */
}
res = ci->func; /* res == final position of 1st result */
L->ci = ci->previous; /* back to caller */
/* move results to proper place */
return moveresults(L, firstResult, res, nres, wanted);
}
/*
** Check appropriate error for stack overflow ("regular" overflow or
** overflow while handling stack overflow). If 'nCalls' is larger than

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