no-nonsense debug information about tail calls

author: Roberto Ierusalimschy <roberto@inf.puc-rio.br> 2003-02-27 08:52:30 -0300
committer: Roberto Ierusalimschy <roberto@inf.puc-rio.br> 2003-02-27 08:52:30 -0300
commit: 92f6e0c1bfb27cad95d99e99912e2e0c509dcc30 (patch)
tree: 1ab713c16652a5a4e667457041ce7364256a6b2c /ldebug.c
parent: 5cd99b82b7fc11c527929e5e95f03767f6432d8e (diff)
download: lua-92f6e0c1bfb27cad95d99e99912e2e0c509dcc30.tar.gz
lua-92f6e0c1bfb27cad95d99e99912e2e0c509dcc30.tar.bz2
lua-92f6e0c1bfb27cad95d99e99912e2e0c509dcc30.zip
1 files changed, 65 insertions, 57 deletions
diff --git a/ldebug.c b/ldebug.c
index 39b27810..e308e080 100644
--- a/ldebug.c
+++ b/ldebug.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ldebug.c,v 1.144 2003/02/11 10:46:24 roberto Exp roberto $
+** $Id: ldebug.c,v 1.145 2003/02/19 10:28:58 roberto Exp roberto $
 ** Debug Interface
 ** See Copyright Notice in lua.h
 */
@@ -93,13 +93,21 @@ LUA_API int lua_gethookcount (lua_State *L) {
 LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
  int status;
-  int ci;
+  CallInfo *ci;
  lua_lock(L);
-  ci = (L->ci - L->base_ci) - level;
+  for (ci = L->ci; level > 0 && ci > L->base_ci; ci--) {
-  if (ci <= 0) status = 0;  /* there is no such level */
+    level--;
+    if (!(ci->state & CI_C))  /* Lua function? */
+      level -= ci->u.l.tailcalls;  /* skip lost tail calls */
+  }
+  if (level > 0 || ci == L->base_ci) status = 0;  /* there is no such level */
+  else if (level < 0) {  /* level is of a lost tail call */
+    status = 1;
+    ar->i_ci = 0;
+  }
  else {
-    ar->i_ci = ci;
    status = 1;
+    ar->i_ci = ci - L->base_ci;
  }
  lua_unlock(L);
  return status;
@@ -150,31 +158,19 @@ LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
 }
-static void infoLproto (lua_Debug *ar, Proto *f) {
-  ar->source = getstr(f->source);
-  ar->linedefined = f->lineDefined;
-  ar->what = "Lua";
-}
 static void funcinfo (lua_State *L, lua_Debug *ar, StkId func) {
-  Closure *cl;
+  Closure *cl = clvalue(func);
-  if (ttisfunction(func))
-    cl = clvalue(func);
-  else {
-    luaG_runerror(L, "value for `lua_getinfo' is not a function");
-    cl = NULL;  /* to avoid warnings */
-  }
  if (cl->c.isC) {
    ar->source = "=[C]";
    ar->linedefined = -1;
    ar->what = "C";
  }
-  else
+  else {
-    infoLproto(ar, cl->l.p);
+    ar->source = getstr(cl->l.p->source);
+    ar->linedefined = cl->l.p->lineDefined;
+    ar->what = (ar->linedefined == 0) ? "main" : "Lua";
+  }
  luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
-  if (ar->linedefined == 0)
-    ar->what = "main";
 }
@@ -190,29 +186,20 @@ static const char *travglobals (lua_State *L, const TObject *o) {
 }
-static void getname (lua_State *L, const TObject *f, lua_Debug *ar) {
+static void info_tailcall (lua_State *L, lua_Debug *ar) {
-  /* try to find a name for given function */
+  ar->name = ar->namewhat = "";
-  if ((ar->name = travglobals(L, f)) != NULL)
+  ar->what = "tail";
-    ar->namewhat = "global";
+  ar->linedefined = ar->currentline = -1;
-  else ar->namewhat = "";  /* not found */
+  ar->source = "=(tail call)";
+  luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
+  ar->nups = 0;
+  setnilvalue(L->top);
 }
+static int getinfo (lua_State *L, const char *what, lua_Debug *ar,
-LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
+                    StkId f, CallInfo *ci) {
-  StkId f;
-  CallInfo *ci;
  int status = 1;
-  lua_lock(L);
-  if (*what != '>') {  /* function is active? */
-    ci = L->base_ci + ar->i_ci;
-    f = ci->base - 1;
-  }
-  else {
-    what++;  /* skip the `>' */
-    ci = NULL;
-    f = L->top - 1;
-  }
  for (; *what; what++) {
    switch (*what) {
      case 'S': {
@@ -224,25 +211,48 @@ LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
        break;
      }
      case 'u': {
-        ar->nups = (ttisfunction(f)) ? clvalue(f)->c.nupvalues : 0;
+        ar->nups = clvalue(f)->c.nupvalues;
        break;
      }
      case 'n': {
        ar->namewhat = (ci) ? getfuncname(ci, &ar->name) : NULL;
-        if (ar->namewhat == NULL)
+        if (ar->namewhat == NULL) {
-          getname(L, f, ar);
+          /* try to find a global name */
+          if ((ar->name = travglobals(L, f)) != NULL)
+            ar->namewhat = "global";
+          else ar->namewhat = "";  /* not found */
+        }
        break;
      }
      case 'f': {
        setobj2s(L->top, f);
-        status = 2;
        break;
      }
      default: status = 0;  /* invalid option */
    }
  }
-  if (!ci) L->top--;  /* pop function */
+  return status;
-  if (status == 2) incr_top(L);
+}
+LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
+  int status = 1;
+  lua_lock(L);
+  if (*what == '>') {
+    StkId f = L->top - 1;
+    if (!ttisfunction(f))
+      luaG_runerror(L, "value for `lua_getinfo' is not a function");
+    status = getinfo(L, what + 1, ar, f, NULL);
+    L->top--;  /* pop function */
+  }
+  else if (ar->i_ci != 0) {  /* no tail call? */
+    CallInfo *ci = L->base_ci + ar->i_ci;
+    lua_assert(ttisfunction(ci->base - 1));
+    status = getinfo(L, what, ar, ci->base - 1, ci);
+  }
+  else
+    info_tailcall(L, ar);
+  if (strchr(what, 'f')) incr_top(L);
  lua_unlock(L);
  return status;
 }
@@ -480,18 +490,16 @@ static const char *getobjname (CallInfo *ci, int stackpos, const char **name) {
 }
-static Instruction getcurrentinstr (CallInfo *ci) {
-  return (!isLua(ci)) ? (Instruction)(-1) :
-                        ci_func(ci)->l.p->code[currentpc(ci)];
-}
 static const char *getfuncname (CallInfo *ci, const char **name) {
  Instruction i;
+  if ((isLua(ci) && ci->u.l.tailcalls > 0) || !isLua(ci - 1))
+    return NULL;  /* calling function is not Lua (or is unknown) */
  ci--;  /* calling function */
-  i = getcurrentinstr(ci);
+  i = ci_func(ci)->l.p->code[currentpc(ci)];
-  return (GET_OPCODE(i) == OP_CALL ? getobjname(ci, GETARG_A(i), name)
+  if (GET_OPCODE(i) == OP_CALL || GET_OPCODE(i) == OP_TAILCALL)
-                                   : NULL);  /* no useful name found */
+    return getobjname(ci, GETARG_A(i), name);
+  else
+    return NULL;  /* no useful name can be found */
 }
author	Roberto Ierusalimschy <roberto@inf.puc-rio.br>	2003-02-27 08:52:30 -0300
committer	Roberto Ierusalimschy <roberto@inf.puc-rio.br>	2003-02-27 08:52:30 -0300
commit	92f6e0c1bfb27cad95d99e99912e2e0c509dcc30 (patch)
tree	1ab713c16652a5a4e667457041ce7364256a6b2c /ldebug.c
parent	5cd99b82b7fc11c527929e5e95f03767f6432d8e (diff)
download	lua-92f6e0c1bfb27cad95d99e99912e2e0c509dcc30.tar.gz lua-92f6e0c1bfb27cad95d99e99912e2e0c509dcc30.tar.bz2 lua-92f6e0c1bfb27cad95d99e99912e2e0c509dcc30.zip

diff --git a/ldebug.c b/ldebug.c index 39b27810..e308e080 100644 --- a/ldebug.c +++ b/ldebug.c
@@ -1,5 +1,5 @@
1	/*	1	/*
2	** $Id: ldebug.c,v 1.144 2003/02/11 10:46:24 roberto Exp roberto $	2	** $Id: ldebug.c,v 1.145 2003/02/19 10:28:58 roberto Exp roberto $
3	** Debug Interface	3	** Debug Interface
4	** See Copyright Notice in lua.h	4	** See Copyright Notice in lua.h
5	*/	5	*/
@@ -93,13 +93,21 @@ LUA_API int lua_gethookcount (lua_State *L) {
93		93
94	LUA_API int lua_getstack (lua_State L, int level, lua_Debug ar) {	94	LUA_API int lua_getstack (lua_State L, int level, lua_Debug ar) {
95	int status;	95	int status;
96	int ci;	96	CallInfo *ci;
97	lua_lock(L);	97	lua_lock(L);
98	ci = (L->ci - L->base_ci) - level;	98	for (ci = L->ci; level > 0 && ci > L->base_ci; ci--) {
99	if (ci <= 0) status = 0; /* there is no such level */	99	level--;
		100	if (!(ci->state & CI_C)) /* Lua function? */
		101	level -= ci->u.l.tailcalls; /* skip lost tail calls */
		102	}
		103	if (level > 0 \|\| ci == L->base_ci) status = 0; /* there is no such level */
		104	else if (level < 0) { /* level is of a lost tail call */
		105	status = 1;
		106	ar->i_ci = 0;
		107	}
100	else {	108	else {
101	ar->i_ci = ci;
102	status = 1;	109	status = 1;
		110	ar->i_ci = ci - L->base_ci;
103	}	111	}
104	lua_unlock(L);	112	lua_unlock(L);
105	return status;	113	return status;
@@ -150,31 +158,19 @@ LUA_API const char lua_setlocal (lua_State L, const lua_Debug *ar, int n) {
150	}	158	}
151		159
152		160
153	static void infoLproto (lua_Debug ar, Proto f) {
154	ar->source = getstr(f->source);
155	ar->linedefined = f->lineDefined;
156	ar->what = "Lua";
157	}
158
159
160	static void funcinfo (lua_State L, lua_Debug ar, StkId func) {	161	static void funcinfo (lua_State L, lua_Debug ar, StkId func) {
161	Closure *cl;	162	Closure *cl = clvalue(func);
162	if (ttisfunction(func))
163	cl = clvalue(func);
164	else {
165	luaG_runerror(L, "value for `lua_getinfo' is not a function");
166	cl = NULL; /* to avoid warnings */
167	}
168	if (cl->c.isC) {	163	if (cl->c.isC) {
169	ar->source = "=[C]";	164	ar->source = "=[C]";
170	ar->linedefined = -1;	165	ar->linedefined = -1;
171	ar->what = "C";	166	ar->what = "C";
172	}	167	}
173	else	168	else {
174	infoLproto(ar, cl->l.p);	169	ar->source = getstr(cl->l.p->source);
		170	ar->linedefined = cl->l.p->lineDefined;
		171	ar->what = (ar->linedefined == 0) ? "main" : "Lua";
		172	}
175	luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);	173	luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
176	if (ar->linedefined == 0)
177	ar->what = "main";
178	}	174	}
179		175
180		176
@@ -190,29 +186,20 @@ static const char travglobals (lua_State L, const TObject *o) {
190	}	186	}
191		187
192		188
193	static void getname (lua_State L, const TObject f, lua_Debug *ar) {	189	static void info_tailcall (lua_State L, lua_Debug ar) {
194	/* try to find a name for given function */	190	ar->name = ar->namewhat = "";
195	if ((ar->name = travglobals(L, f)) != NULL)	191	ar->what = "tail";
196	ar->namewhat = "global";	192	ar->linedefined = ar->currentline = -1;
197	else ar->namewhat = ""; /* not found */	193	ar->source = "=(tail call)";
		194	luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
		195	ar->nups = 0;
		196	setnilvalue(L->top);
198	}	197	}
199		198
200		199
201		200	static int getinfo (lua_State L, const char what, lua_Debug *ar,
202	LUA_API int lua_getinfo (lua_State L, const char what, lua_Debug *ar) {	201	StkId f, CallInfo *ci) {
203	StkId f;
204	CallInfo *ci;
205	int status = 1;	202	int status = 1;
206	lua_lock(L);
207	if (what != '>') { / function is active? */
208	ci = L->base_ci + ar->i_ci;
209	f = ci->base - 1;
210	}
211	else {
212	what++; /* skip the `>' */
213	ci = NULL;
214	f = L->top - 1;
215	}
216	for (; *what; what++) {	203	for (; *what; what++) {
217	switch (*what) {	204	switch (*what) {
218	case 'S': {	205	case 'S': {
@@ -224,25 +211,48 @@ LUA_API int lua_getinfo (lua_State L, const char what, lua_Debug *ar) {
224	break;	211	break;
225	}	212	}
226	case 'u': {	213	case 'u': {
227	ar->nups = (ttisfunction(f)) ? clvalue(f)->c.nupvalues : 0;	214	ar->nups = clvalue(f)->c.nupvalues;
228	break;	215	break;
229	}	216	}
230	case 'n': {	217	case 'n': {
231	ar->namewhat = (ci) ? getfuncname(ci, &ar->name) : NULL;	218	ar->namewhat = (ci) ? getfuncname(ci, &ar->name) : NULL;
232	if (ar->namewhat == NULL)	219	if (ar->namewhat == NULL) {
233	getname(L, f, ar);	220	/* try to find a global name */
		221	if ((ar->name = travglobals(L, f)) != NULL)
		222	ar->namewhat = "global";
		223	else ar->namewhat = ""; /* not found */
		224	}
234	break;	225	break;
235	}	226	}
236	case 'f': {	227	case 'f': {
237	setobj2s(L->top, f);	228	setobj2s(L->top, f);
238	status = 2;
239	break;	229	break;
240	}	230	}
241	default: status = 0; /* invalid option */	231	default: status = 0; /* invalid option */
242	}	232	}
243	}	233	}
244	if (!ci) L->top--; /* pop function */	234	return status;
245	if (status == 2) incr_top(L);	235	}
		236
		237
		238	LUA_API int lua_getinfo (lua_State L, const char what, lua_Debug *ar) {
		239	int status = 1;
		240	lua_lock(L);
		241	if (*what == '>') {
		242	StkId f = L->top - 1;
		243	if (!ttisfunction(f))
		244	luaG_runerror(L, "value for `lua_getinfo' is not a function");
		245	status = getinfo(L, what + 1, ar, f, NULL);
		246	L->top--; /* pop function */
		247	}
		248	else if (ar->i_ci != 0) { /* no tail call? */
		249	CallInfo *ci = L->base_ci + ar->i_ci;
		250	lua_assert(ttisfunction(ci->base - 1));
		251	status = getinfo(L, what, ar, ci->base - 1, ci);
		252	}
		253	else
		254	info_tailcall(L, ar);
		255	if (strchr(what, 'f')) incr_top(L);
246	lua_unlock(L);	256	lua_unlock(L);
247	return status;	257	return status;
248	}	258	}
@@ -480,18 +490,16 @@ static const char getobjname (CallInfo ci, int stackpos, const char **name) {
480	}	490	}
481		491
482		492
483	static Instruction getcurrentinstr (CallInfo *ci) {
484	return (!isLua(ci)) ? (Instruction)(-1) :
485	ci_func(ci)->l.p->code[currentpc(ci)];
486	}
487
488
489	static const char getfuncname (CallInfo ci, const char **name) {	493	static const char getfuncname (CallInfo ci, const char **name) {
490	Instruction i;	494	Instruction i;
		495	if ((isLua(ci) && ci->u.l.tailcalls > 0) \|\| !isLua(ci - 1))
		496	return NULL; /* calling function is not Lua (or is unknown) */
491	ci--; /* calling function */	497	ci--; /* calling function */
492	i = getcurrentinstr(ci);	498	i = ci_func(ci)->l.p->code[currentpc(ci)];
493	return (GET_OPCODE(i) == OP_CALL ? getobjname(ci, GETARG_A(i), name)	499	if (GET_OPCODE(i) == OP_CALL \|\| GET_OPCODE(i) == OP_TAILCALL)
494	: NULL); /* no useful name found */	500	return getobjname(ci, GETARG_A(i), name);
		501	else
		502	return NULL; /* no useful name can be found */
495	}	503	}
496		504
497		505