luaD_call is more uniform

4 files changed, 42 insertions, 46 deletions

diff --git a/ldebug.c b/ldebug.c
index f3b92af9..1aff2064 100644
--- a/ldebug.c
+++ b/ldebug.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ldebug.c,v 1.44 2000/10/05 12:14:08 roberto Exp roberto $
+** $Id: ldebug.c,v 1.45 2000/10/05 13:00:17 roberto Exp roberto $
 ** Debug Interface
 ** See Copyright Notice in lua.h
 */
@@ -92,8 +92,8 @@ static int lua_nups (StkId f) {
 
 int luaG_getline (int *lineinfo, int pc, int refline, int *prefi) {
   int refi;
-  if (lineinfo == NULL) return -1;  /* no line info */
-  else if (pc == -1) return refline;  /* function preamble */
+  if (lineinfo == NULL || pc == -1)
+    return -1;  /* no line info or function is not active */
   refi = prefi ? *prefi : 0;
   if (lineinfo[refi] < 0)
     refline += -lineinfo[refi++]; 
@@ -124,7 +124,10 @@ int luaG_getline (int *lineinfo, int pc, int refline, int *prefi) {
 static int lua_currentpc (StkId f) {
   CallInfo *ci = infovalue(f);
   LUA_ASSERT(isLmark(f), "function has no pc");
-  return (*ci->pc - ci->func->f.l->code) - 1;
+  if (ci->pc)
+    return (*ci->pc - ci->func->f.l->code) - 1;
+  else
+    return -1;  /* function is not active */
 }
 
 
diff --git a/ldo.c b/ldo.c
index 11d6c5a6..a3752042 100644
--- a/ldo.c
+++ b/ldo.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ldo.c,v 1.102 2000/10/05 12:14:08 roberto Exp roberto $
+** $Id: ldo.c,v 1.103 2000/10/05 13:00:17 roberto Exp roberto $
 ** Stack and Call structure of Lua
 ** See Copyright Notice in lua.h
 */
@@ -41,7 +41,7 @@ void luaD_init (lua_State *L, int stacksize) {
 
 
 void luaD_checkstack (lua_State *L, int n) {
-  if (L->stack_last-L->top <= n) {  /* stack overflow? */
+  if (L->stack_last - L->top <= n) {  /* stack overflow? */
     if (L->stack_last-L->stack > (L->stacksize-1)) {
       /* overflow while handling overflow: do what?? */
       L->top -= EXTRA_STACK;
@@ -112,19 +112,19 @@ void luaD_lineHook (lua_State *L, StkId func, int line, lua_Hook linehook) {
 }
 
 
-void luaD_callHook (lua_State *L, StkId func, lua_Hook callhook,
+static void luaD_callHook (lua_State *L, StkId func, lua_Hook callhook,
                     const char *event) {
   if (L->allowhooks) {
     lua_Debug ar;
     ar._func = func;
     ar.event = event;
+    infovalue(func)->pc = NULL;  /* function is not active */
     dohook(L, &ar, callhook);
   }
 }
 
 
 static StkId callCclosure (lua_State *L, const struct Closure *cl, StkId base) {
-  lua_Hook callhook = L->callhook;
   int nup = cl->nupvalues;  /* number of upvalues */
   StkId old_Cbase = L->Cbase;
   int n;
@@ -132,11 +132,7 @@ static StkId callCclosure (lua_State *L, const struct Closure *cl, StkId base) {
   luaD_checkstack(L, nup+LUA_MINSTACK);  /* ensure minimum stack size */
   for (n=0; n<nup; n++)  /* copy upvalues as extra arguments */
     *(L->top++) = cl->upvalue[n];
-  if (callhook)
-    luaD_callHook(L, base-1, callhook, "call");
   n = (*cl->f.c)(L);  /* do the actual call */
-  if (callhook)  /* same hook that was active at entry */
-    luaD_callHook(L, base-1, callhook, "return");
   L->Cbase = old_Cbase;  /* restore old C base */
   return L->top - n;  /* return index of first result */
 }
@@ -159,6 +155,7 @@ void luaD_callTM (lua_State *L, Closure *f, int nParams, int nResults) {
 ** The number of results is nResults, unless nResults=LUA_MULTRET.
 */ 
 void luaD_call (lua_State *L, StkId func, int nResults) {
+  lua_Hook callhook;
   StkId firstResult;
   CallInfo ci;
   Closure *cl;
@@ -175,22 +172,29 @@ void luaD_call (lua_State *L, StkId func, int nResults) {
   ci.func = cl;
   infovalue(func) = &ci;
   ttype(func) = LUA_TMARK;
-  if (cl->isC)
-    firstResult = callCclosure(L, cl, func+1);
-  else
-    firstResult = luaV_execute(L, cl, func+1);
+  callhook = L->callhook;
+  if (callhook)
+    luaD_callHook(L, func, callhook, "call");
+  firstResult = (cl->isC ? callCclosure(L, cl, func+1) :
+                           luaV_execute(L, cl, func+1));
+  if (callhook)  /* same hook that was active at entry */
+    luaD_callHook(L, func, callhook, "return");
   LUA_ASSERT(ttype(func) == LUA_TMARK, "invalid tag");
-  /* adjust the number of results */
-  if (nResults == LUA_MULTRET)
-    nResults = L->top - firstResult;
-  else
-    luaD_adjusttop(L, firstResult, nResults);
   /* move results to `func' (to erase parameters and function) */
-  while (nResults) {
-    *func++ = *(L->top - nResults);
-    nResults--;
+  if (nResults == LUA_MULTRET) {
+    while (firstResult < L->top)  /* copy all results */
+      *func++ = *firstResult++;
+    L->top = func;
+  }
+  else {  /* copy at most `nResults' */
+    for (; nResults > 0 && firstResult < L->top; nResults--)
+      *func++ = *firstResult++;
+    L->top = func;
+    for (; nResults > 0; nResults--) {  /* if there are not enough results */
+      ttype(L->top) = LUA_TNIL;  /* adjust the stack */
+      incr_top;  /* must check stack space */
+    }
   }
-  L->top = func;
   luaC_checkGC(L);
 }
 
diff --git a/ldo.h b/ldo.h
index 1058d34e..7cf5af38 100644
--- a/ldo.h
+++ b/ldo.h
@@ -1,5 +1,5 @@
 /*
-** $Id: ldo.h,v 1.26 2000/10/04 12:16:08 roberto Exp roberto $
+** $Id: ldo.h,v 1.27 2000/10/05 13:00:17 roberto Exp roberto $
 ** Stack and Call structure of Lua
 ** See Copyright Notice in lua.h
 */
@@ -22,8 +22,6 @@
 void luaD_init (lua_State *L, int stacksize);
 void luaD_adjusttop (lua_State *L, StkId base, int extra);
 void luaD_lineHook (lua_State *L, StkId func, int line, lua_Hook linehook);
-void luaD_callHook (lua_State *L, StkId func, lua_Hook callhook,
-                    const char *event);
 void luaD_call (lua_State *L, StkId func, int nResults);
 void luaD_callTM (lua_State *L, Closure *f, int nParams, int nResults);
 void luaD_checkstack (lua_State *L, int n);
diff --git a/lvm.c b/lvm.c
index 48f78d01..356dc4a1 100644
--- a/lvm.c
+++ b/lvm.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.c,v 1.143 2000/10/05 12:14:08 roberto Exp roberto $
+** $Id: lvm.c,v 1.144 2000/10/05 13:00:17 roberto Exp roberto $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -67,7 +67,7 @@ int luaV_tostring (lua_State *L, TObject *obj) {  /* LUA_NUMBER */
 static void traceexec (lua_State *L, StkId base, StkId top, lua_Hook linehook) {
   CallInfo *ci = infovalue(base-1);
   int *lineinfo = ci->func->f.l->lineinfo;
-  int pc = (*ci->pc - 1) - ci->func->f.l->code;
+  int pc = (*ci->pc - ci->func->f.l->code) - 1;
   int newline;
   if (pc == 0) {  /* may be first time? */
     ci->line = 1;
@@ -349,22 +349,18 @@ static void adjust_varargs (lua_State *L, StkId base, int nfixargs) {
 ** Returns n such that the the results are between [n,top).
 */
 StkId luaV_execute (lua_State *L, const Closure *cl, StkId base) {
-  const Proto *tf = cl->f.l;
+  const Proto *const tf = cl->f.l;
   StkId top;  /* keep top local, for performance */
   const Instruction *pc = tf->code;
-  TString **kstr = tf->kstr;
-  lua_Hook callhook = L->callhook;
-  lua_Hook linehook;  /* set it only after calling eventual call hook */
+  TString **const kstr = tf->kstr;
+  const lua_Hook linehook = L->linehook;
   infovalue(base-1)->pc = &pc;
   luaD_checkstack(L, tf->maxstacksize+EXTRA_STACK);
   if (tf->is_vararg)  /* varargs? */
     adjust_varargs(L, base, tf->numparams);
   else
     luaD_adjusttop(L, base, tf->numparams);
-  if (callhook)
-    luaD_callHook(L, base-1, callhook, "call");
   top = L->top;
-  linehook = L->linehook;
   /* main loop of interpreter */
   for (;;) {
     const Instruction i = *pc++;
@@ -373,12 +369,11 @@ StkId luaV_execute (lua_State *L, const Closure *cl, StkId base) {
     switch (GET_OPCODE(i)) {
       case OP_END: {
         L->top = top;
-        goto endloop;
+        return top;
       }
       case OP_RETURN: {
         L->top = top;
-        top = base+GETARG_U(i);
-        goto endloop;
+        return base+GETARG_U(i);
       }
       case OP_CALL: {
         int nres = GETARG_B(i);
@@ -391,8 +386,7 @@ StkId luaV_execute (lua_State *L, const Closure *cl, StkId base) {
       case OP_TAILCALL: {
         L->top = top;
         luaD_call(L, base+GETARG_A(i), LUA_MULTRET);
-        top = base+GETARG_B(i);
-        goto endloop;
+        return base+GETARG_B(i);
       }
       case OP_PUSHNIL: {
         int n = GETARG_U(i);
@@ -712,8 +706,5 @@ StkId luaV_execute (lua_State *L, const Closure *cl, StkId base) {
         break;
       }
     }
-  } endloop:
-  if (callhook)  /* same hook that was active at entry */
-    luaD_callHook(L, base-1, callhook, "return");
-  return top;
+  }
 }