This is my patch
[ 587993 ] SET_LINENO killer
Remove SET_LINENO. Tracing is now supported by inspecting co_lnotab.
Many sundry changes to document and adapt to this change.
diff --git a/Doc/lib/libdis.tex b/Doc/lib/libdis.tex
index 16b692d..567c0ee 100644
--- a/Doc/lib/libdis.tex
+++ b/Doc/lib/libdis.tex
@@ -23,17 +23,15 @@
\begin{verbatim}
>>> dis.dis(myfunc)
- 0 SET_LINENO 1
-
- 3 SET_LINENO 2
- 6 LOAD_GLOBAL 0 (len)
- 9 LOAD_FAST 0 (alist)
- 12 CALL_FUNCTION 1
- 15 RETURN_VALUE
- 16 LOAD_CONST 0 (None)
- 19 RETURN_VALUE
+ 2 0 LOAD_GLOBAL 0 (len)
+ 3 LOAD_FAST 0 (alist)
+ 6 CALL_FUNCTION 1
+ 9 RETURN_VALUE
+ 10 RETURN_NONE
\end{verbatim}
+(The ``2'' is a line number).
+
The \module{dis} module defines the following functions and constants:
\begin{funcdesc}{dis}{\optional{bytesource}}
@@ -56,6 +54,7 @@
was provided. The output is divided in the following columns:
\begin{enumerate}
+\item the line number, for the first instruction of each line
\item the current instruction, indicated as \samp{-->},
\item a labelled instruction, indicated with \samp{>\code{>}},
\item the address of the instruction,
@@ -402,6 +401,14 @@
Returns with TOS to the caller of the function.
\end{opcodedesc}
+\begin{opcodedesc}{RETURN_NONE}{}
+Returns \constant{None} to the caller of the function. This opcode is
+generated as the last opcode of every function and only then, for
+reasons to do with tracing support. See the comments in the function
+\cfunction{maybe_call_line_trace} in \file{Python/ceval.c} for the
+gory details. \versionadded{2.3}.
+\end{opcodedesc}
+
\begin{opcodedesc}{YIELD_VALUE}{}
Pops \code{TOS} and yields it from a generator.
\end{opcodedesc}
@@ -621,7 +628,7 @@
\end{opcodedesc}
\begin{opcodedesc}{SET_LINENO}{lineno}
-Sets the current line number to \var{lineno}.
+This opcode is obsolete.
\end{opcodedesc}
\begin{opcodedesc}{RAISE_VARARGS}{argc}
diff --git a/Doc/lib/libtraceback.tex b/Doc/lib/libtraceback.tex
index 2b20b0c..a74613b 100644
--- a/Doc/lib/libtraceback.tex
+++ b/Doc/lib/libtraceback.tex
@@ -118,10 +118,10 @@
\begin{funcdesc}{tb_lineno}{tb}
This function returns the current line number set in the traceback
-object. This is normally the same as the \code{\var{tb}.tb_lineno}
-field of the object, but when optimization is used (the -O flag) this
-field is not updated correctly; this function calculates the correct
-value.
+object. This function was necessary because in versions of Python
+prior to 2.3 when the \programopt{O} flag was passed to Python the
+\code{\var{tb}.tb_lineno} was not updated correctly. This function
+has no use in versions past 2.3.
\end{funcdesc}
diff --git a/Doc/tut/tut.tex b/Doc/tut/tut.tex
index c6081c6..4bc571a 100644
--- a/Doc/tut/tut.tex
+++ b/Doc/tut/tut.tex
@@ -2340,12 +2340,11 @@
\item
When the Python interpreter is invoked with the \programopt{-O} flag,
-optimized code is generated and stored in \file{.pyo} files.
-The optimizer currently doesn't help much; it only removes
-\keyword{assert} statements and \code{SET_LINENO} instructions.
-When \programopt{-O} is used, \emph{all} bytecode is optimized;
-\code{.pyc} files are ignored and \code{.py} files are compiled to
-optimized bytecode.
+optimized code is generated and stored in \file{.pyo} files. The
+optimizer currently doesn't help much; it only removes
+\keyword{assert} statements. When \programopt{-O} is used, \emph{all}
+bytecode is optimized; \code{.pyc} files are ignored and \code{.py}
+files are compiled to optimized bytecode.
\item
Passing two \programopt{-O} flags to the Python interpreter
diff --git a/Doc/whatsnew/whatsnew23.tex b/Doc/whatsnew/whatsnew23.tex
index 0d7d774..f919d7e 100644
--- a/Doc/whatsnew/whatsnew23.tex
+++ b/Doc/whatsnew/whatsnew23.tex
@@ -658,7 +658,6 @@
\end{itemize}
-
%======================================================================
\section{New and Improved Modules}
@@ -987,9 +986,9 @@
when running Python's \file{configure} script. (Contributed by Ondrej
Palkovsky.)
-\item The \csimplemacro{DL_EXPORT} and \csimplemacro{DL_IMPORT} macros are now
-deprecated. Initialization functions for Python extension modules
-should now be declared using the new macro
+\item The \csimplemacro{DL_EXPORT} and \csimplemacro{DL_IMPORT} macros
+are now deprecated. Initialization functions for Python extension
+modules should now be declared using the new macro
\csimplemacro{PyMODINIT_FUNC}, while the Python core will generally
use the \csimplemacro{PyAPI_FUNC} and \csimplemacro{PyAPI_DATA}
macros.
@@ -1076,6 +1075,29 @@
\item The tools used to build the documentation now work under Cygwin
as well as \UNIX.
+\item The \code{SET_LINENO} opcode has been removed. Back in the
+mists of time, this opcode was needed to produce line numbers in
+tracebacks and support trace functions (for, e.g., \module{pdb}).
+Since Python 1.5, the line numbers in tracebacks have been computed
+using a different mechanism that works with ``python -O''. For Python
+2.3 Michael Hudson implemented a similar scheme to determine when to
+call the trace function, removing the need for \code{SET_LINENO}
+entirely.
+
+Python code will be hard pushed to notice a difference from this
+change, apart from a slight speed up when python is run without
+\programopt{-O}.
+
+C extensions that access the \member{f_lineno} field of frame objects
+should instead call \code{PyCode_Addr2Line(f->f_code, f->f_lasti)}.
+This will have the added effect of making the code work as desired
+under ``python -O'' in earlier versions of Python.
+
+To make tracing work as expected, it was found necessary to add a new
+opcode, \cdata{RETURN_NONE}, to the VM. If you want to know why, read
+the comments in the function \cfunction{maybe_call_line_trace} in
+\file{Python/ceval.c}.
+
\end{itemize}
diff --git a/Include/opcode.h b/Include/opcode.h
index 2e20246..28d0ae43 100644
--- a/Include/opcode.h
+++ b/Include/opcode.h
@@ -71,6 +71,9 @@
#define INPLACE_OR 79
#define BREAK_LOOP 80
+#define RETURN_NONE 81 /* *only* for function epilogues
+ -- see comments in
+ ceval.c:maybe_call_line_trace for why */
#define LOAD_LOCALS 82
#define RETURN_VALUE 83
#define IMPORT_STAR 84
@@ -119,8 +122,6 @@
#define STORE_FAST 125 /* Local variable number */
#define DELETE_FAST 126 /* Local variable number */
-#define SET_LINENO 127 /* Current line number */
-
#define RAISE_VARARGS 130 /* Number of raise arguments (1, 2 or 3) */
/* CALL_FUNCTION_XXX opcodes defined below depend on this definition */
#define CALL_FUNCTION 131 /* #args + (#kwargs<<8) */
diff --git a/Lib/dis.py b/Lib/dis.py
index 2674094..a1cc215 100644
--- a/Lib/dis.py
+++ b/Lib/dis.py
@@ -55,6 +55,20 @@
def disassemble(co, lasti=-1):
"""Disassemble a code object."""
code = co.co_code
+
+ byte_increments = [ord(c) for c in co.co_lnotab[0::2]]
+ line_increments = [ord(c) for c in co.co_lnotab[1::2]]
+ table_length = len(byte_increments) # == len(line_increments)
+
+ lineno = co.co_firstlineno
+ table_index = 0
+ while (table_index < table_length
+ and byte_increments[table_index] == 0):
+ lineno += line_increments[table_index]
+ table_index += 1
+ addr = 0
+ line_incr = 0
+
labels = findlabels(code)
n = len(code)
i = 0
@@ -63,7 +77,23 @@
while i < n:
c = code[i]
op = ord(c)
- if op == SET_LINENO and i > 0: print # Extra blank line
+
+ if i >= addr:
+ lineno += line_incr
+ while table_index < table_length:
+ addr += byte_increments[table_index]
+ line_incr = line_increments[table_index]
+ table_index += 1
+ if line_incr:
+ break
+ else:
+ addr = sys.maxint
+ if i > 0:
+ print
+ print "%3d"%lineno,
+ else:
+ print ' ',
+
if i == lasti: print '-->',
else: print ' ',
if i in labels: print '>>',
@@ -224,6 +254,7 @@
def_op('INPLACE_OR', 79)
def_op('BREAK_LOOP', 80)
+def_op('RETURN_NONE', 81)
def_op('LOAD_LOCALS', 82)
def_op('RETURN_VALUE', 83)
def_op('IMPORT_STAR', 84)
@@ -277,9 +308,6 @@
def_op('DELETE_FAST', 126) # Local variable number
haslocal.append(126)
-def_op('SET_LINENO', 127) # Current line number
-SET_LINENO = 127
-
def_op('RAISE_VARARGS', 130) # Number of raise arguments (1, 2, or 3)
def_op('CALL_FUNCTION', 131) # #args + (#kwargs << 8)
def_op('MAKE_FUNCTION', 132) # Number of args with default values
diff --git a/Lib/inspect.py b/Lib/inspect.py
index be2da41..96677b7 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -711,7 +711,7 @@
raise TypeError, 'arg is not a frame or traceback object'
filename = getsourcefile(frame) or getfile(frame)
- lineno = getlineno(frame)
+ lineno = frame.f_lineno
if context > 0:
start = lineno - 1 - context//2
try:
@@ -730,18 +730,8 @@
def getlineno(frame):
"""Get the line number from a frame object, allowing for optimization."""
- # Written by Marc-André Lemburg; revised by Jim Hugunin and Fredrik Lundh.
- lineno = frame.f_lineno
- code = frame.f_code
- if hasattr(code, 'co_lnotab'):
- table = code.co_lnotab
- lineno = code.co_firstlineno
- addr = 0
- for i in range(0, len(table), 2):
- addr = addr + ord(table[i])
- if addr > frame.f_lasti: break
- lineno = lineno + ord(table[i+1])
- return lineno
+ # FrameType.f_lineno is now a descriptor that grovels co_lnotab
+ return frame.f_lineno
def getouterframes(frame, context=1):
"""Get a list of records for a frame and all higher (calling) frames.
diff --git a/Lib/pdb.py b/Lib/pdb.py
index 3786ed9..c6164ad 100755
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -105,7 +105,13 @@
if len(line) > 0 and line[0] != '#':
self.onecmd(line)
- # Override Bdb methods (except user_call, for now)
+ # Override Bdb methods
+
+ def user_call(self, frame, argument_list):
+ """This method is called when there is the remote possibility
+ that we ever need to stop in this function."""
+ print '--Call--'
+ self.interaction(frame, None)
def user_line(self, frame):
"""This function is called when we stop or break at this line."""
diff --git a/Lib/test/test_hotshot.py b/Lib/test/test_hotshot.py
index dad2bd4..d410099 100644
--- a/Lib/test/test_hotshot.py
+++ b/Lib/test/test_hotshot.py
@@ -91,10 +91,8 @@
f_lineno = f.func_code.co_firstlineno
g_lineno = g.func_code.co_firstlineno
events = [(ENTER, ("test_hotshot", g_lineno, "g")),
- (LINE, ("test_hotshot", g_lineno, "g")),
(LINE, ("test_hotshot", g_lineno+1, "g")),
(ENTER, ("test_hotshot", f_lineno, "f")),
- (LINE, ("test_hotshot", f_lineno, "f")),
(LINE, ("test_hotshot", f_lineno+1, "f")),
(LINE, ("test_hotshot", f_lineno+2, "f")),
(EXIT, ("test_hotshot", f_lineno, "f")),
diff --git a/Lib/traceback.py b/Lib/traceback.py
index c22f576..4910a37 100644
--- a/Lib/traceback.py
+++ b/Lib/traceback.py
@@ -59,7 +59,7 @@
n = 0
while tb is not None and (limit is None or n < limit):
f = tb.tb_frame
- lineno = tb_lineno(tb)
+ lineno = tb.tb_lineno
co = f.f_code
filename = co.co_filename
name = co.co_name
@@ -92,7 +92,7 @@
n = 0
while tb is not None and (limit is None or n < limit):
f = tb.tb_frame
- lineno = tb_lineno(tb)
+ lineno = tb.tb_lineno
co = f.f_code
filename = co.co_filename
name = co.co_name
@@ -263,7 +263,7 @@
list = []
n = 0
while f is not None and (limit is None or n < limit):
- lineno = f.f_lineno # XXX Too bad if -O is used
+ lineno = f.f_lineno
co = f.f_code
filename = co.co_filename
name = co.co_name
@@ -279,23 +279,6 @@
def tb_lineno(tb):
"""Calculate correct line number of traceback given in tb.
- Even works with -O on.
+ Obsolete in 2.3.
"""
- # Coded by Marc-Andre Lemburg from the example of PyCode_Addr2Line()
- # in compile.c.
- # Revised version by Jim Hugunin to work with JPython too.
-
- c = tb.tb_frame.f_code
- if not hasattr(c, 'co_lnotab'):
- return tb.tb_lineno
-
- tab = c.co_lnotab
- line = c.co_firstlineno
- stopat = tb.tb_lasti
- addr = 0
- for i in range(0, len(tab), 2):
- addr = addr + ord(tab[i])
- if addr > stopat:
- break
- line = line + ord(tab[i+1])
- return line
+ return tb.tb_lineno
diff --git a/Misc/NEWS b/Misc/NEWS
index 5abfb42..2c9d83f 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -57,6 +57,11 @@
Core and builtins
+- SET_LINENO is gone. co_lnotab is now consulted to determine when to
+ call the trace function. C code that accessed f_lineno should call
+ PyCode_Addr2Line instead (f_lineno is still there, but not kept up
+ to date).
+
- There's a new warning category, FutureWarning. This is used to warn
about a number of situations where the value or sign of an integer
result will change in Python 2.4 as a result of PEP 237 (integer
diff --git a/Modules/_hotshot.c b/Modules/_hotshot.c
index 1e8f4f9..2ca4486 100644
--- a/Modules/_hotshot.c
+++ b/Modules/_hotshot.c
@@ -152,7 +152,7 @@
* Low bits: Opcode: Meaning:
* 0x00 ENTER enter a frame
* 0x01 EXIT exit a frame
- * 0x02 LINENO SET_LINENO instruction was executed
+ * 0x02 LINENO execution moved onto a different line
* 0x03 OTHER more bits are needed to deecode
*
* If the type is OTHER, the record is not packed so tightly, and the
@@ -888,9 +888,12 @@
case PyTrace_LINE:
if (self->linetimings)
- return pack_lineno_tdelta(self, frame->f_lineno, get_tdelta(self));
+ return pack_lineno_tdelta(self, PyCode_Addr2Line(frame->f_code,
+ frame->f_lasti),
+ get_tdelta(self));
else
- return pack_lineno(self, frame->f_lineno);
+ return pack_lineno(self, PyCode_Addr2Line(frame->f_code,
+ frame->f_lasti));
default:
/* ignore PyTrace_EXCEPTION */
@@ -1227,8 +1230,8 @@
"\n"
"closed: True if the profiler has already been closed.\n"
"frametimings: True if ENTER/EXIT events collect timing information.\n"
-"lineevents: True if SET_LINENO events are reported to the profiler.\n"
-"linetimings: True if SET_LINENO events collect timing information.");
+"lineevents: True if line events are reported to the profiler.\n"
+"linetimings: True if line events collect timing information.");
static PyTypeObject ProfilerType = {
PyObject_HEAD_INIT(NULL)
diff --git a/Objects/frameobject.c b/Objects/frameobject.c
index dfb3a2e..7b6ea26 100644
--- a/Objects/frameobject.c
+++ b/Objects/frameobject.c
@@ -16,7 +16,6 @@
{"f_builtins", T_OBJECT, OFF(f_builtins),RO},
{"f_globals", T_OBJECT, OFF(f_globals), RO},
{"f_lasti", T_INT, OFF(f_lasti), RO},
- {"f_lineno", T_INT, OFF(f_lineno), RO},
{"f_restricted",T_INT, OFF(f_restricted),RO},
{"f_trace", T_OBJECT, OFF(f_trace)},
{"f_exc_type", T_OBJECT, OFF(f_exc_type)},
@@ -33,8 +32,19 @@
return f->f_locals;
}
+static PyObject *
+frame_getlineno(PyFrameObject *f, void *closure)
+{
+ int lineno;
+
+ lineno = PyCode_Addr2Line(f->f_code, f->f_lasti);
+
+ return PyInt_FromLong(lineno);
+}
+
static PyGetSetDef frame_getsetlist[] = {
{"f_locals", (getter)frame_getlocals, NULL, NULL},
+ {"f_lineno", (getter)frame_getlineno, NULL, NULL},
{0}
};
@@ -306,7 +316,7 @@
f->f_exc_type = f->f_exc_value = f->f_exc_traceback = NULL;
f->f_tstate = tstate;
- f->f_lasti = 0;
+ f->f_lasti = -1;
f->f_lineno = code->co_firstlineno;
f->f_restricted = (builtins != tstate->interp->builtins);
f->f_iblock = 0;
diff --git a/Python/ceval.c b/Python/ceval.c
index 50ea9c3..6985846 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -51,6 +51,9 @@
static void call_trace_protected(Py_tracefunc, PyObject *,
PyFrameObject *, int);
static void call_exc_trace(Py_tracefunc, PyObject *, PyFrameObject *);
+static void maybe_call_line_trace(int, Py_tracefunc, PyObject *,
+ PyFrameObject *, int *, int *);
+
static PyObject *apply_slice(PyObject *, PyObject *, PyObject *);
static int assign_slice(PyObject *, PyObject *,
PyObject *, PyObject *);
@@ -499,6 +502,16 @@
PyObject *retval = NULL; /* Return value */
PyThreadState *tstate = PyThreadState_GET();
PyCodeObject *co;
+
+ /* when tracing we set things up so that
+
+ not (instr_lb <= current_bytecode_offset < instr_ub)
+
+ is true when the line being executed has changed. The
+ initial values are such as to make this false the first
+ time it is tested. */
+ int instr_ub = -1, instr_lb = 0;
+
unsigned char *first_instr;
PyObject *names;
PyObject *consts;
@@ -586,7 +599,12 @@
fastlocals = f->f_localsplus;
freevars = f->f_localsplus + f->f_nlocals;
_PyCode_GETCODEPTR(co, &first_instr);
- next_instr = first_instr + f->f_lasti;
+ if (f->f_lasti < 0) {
+ next_instr = first_instr;
+ }
+ else {
+ next_instr = first_instr + f->f_lasti;
+ }
stack_pointer = f->f_stacktop;
assert(stack_pointer != NULL);
f->f_stacktop = NULL; /* remains NULL unless yield suspends frame */
@@ -637,8 +655,9 @@
w = NULL;
for (;;) {
- assert(stack_pointer >= f->f_valuestack); /* else underflow */
- assert(STACK_LEVEL() <= f->f_stacksize); /* else overflow */
+ assert(stack_pointer >= f->f_valuestack); /* else underflow */
+ assert(STACK_LEVEL() <= f->f_stacksize); /* else overflow */
+
/* Do periodic things. Doing this every time through
the loop would add too much overhead, so we do it
only every Nth instruction. We also do it if
@@ -658,8 +677,8 @@
#if !defined(HAVE_SIGNAL_H) || defined(macintosh)
/* If we have true signals, the signal handler
will call Py_AddPendingCall() so we don't
- have to call sigcheck(). On the Mac and
- DOS, alas, we have to call it. */
+ have to call PyErr_CheckSignals(). On the
+ Mac and DOS, alas, we have to call it. */
if (PyErr_CheckSignals()) {
why = WHY_EXCEPTION;
goto on_error;
@@ -686,9 +705,7 @@
fast_next_opcode:
/* Extract opcode and argument */
-#if defined(Py_DEBUG) || defined(LLTRACE)
f->f_lasti = INSTR_OFFSET();
-#endif
opcode = NEXTOP();
if (HAS_ARG(opcode))
@@ -708,15 +725,26 @@
if (lltrace) {
if (HAS_ARG(opcode)) {
printf("%d: %d, %d\n",
- (int) (INSTR_OFFSET() - 3),
- opcode, oparg);
+ f->f_lasti, opcode, oparg);
}
else {
printf("%d: %d\n",
- (int) (INSTR_OFFSET() - 1), opcode);
+ f->f_lasti, opcode);
}
}
#endif
+
+ /* line-by-line tracing support */
+
+ if (tstate->c_tracefunc != NULL && !tstate->tracing) {
+ /* see maybe_call_line_trace
+ for expository comments */
+ maybe_call_line_trace(opcode,
+ tstate->c_tracefunc,
+ tstate->c_traceobj,
+ f, &instr_lb, &instr_ub);
+ }
+
/* Main switch on opcode */
switch (opcode) {
@@ -728,26 +756,6 @@
/* case STOP_CODE: this is an error! */
- case SET_LINENO:
-#ifdef LLTRACE
- if (lltrace)
- printf("--- %s:%d \n", filename, oparg);
-#endif
- f->f_lineno = oparg;
- if (tstate->c_tracefunc == NULL || tstate->tracing)
- goto fast_next_opcode;
- /* Trace each line of code reached */
- f->f_lasti = INSTR_OFFSET();
- /* Inline call_trace() for performance: */
- tstate->tracing++;
- tstate->use_tracing = 0;
- err = (tstate->c_tracefunc)(tstate->c_traceobj, f,
- PyTrace_LINE, Py_None);
- tstate->use_tracing = (tstate->c_tracefunc
- || tstate->c_profilefunc);
- tstate->tracing--;
- break;
-
case LOAD_FAST:
x = GETLOCAL(oparg);
if (x != NULL) {
@@ -1504,9 +1512,17 @@
why = WHY_RETURN;
break;
+ case RETURN_NONE:
+ retval = Py_None;
+ Py_INCREF(retval);
+ why = WHY_RETURN;
+ break;
+
case YIELD_VALUE:
retval = POP();
f->f_stacktop = stack_pointer;
+ /* abuse the lasti field: here it points to
+ the *next* instruction */
f->f_lasti = INSTR_OFFSET();
why = WHY_YIELD;
break;
@@ -1954,7 +1970,6 @@
int n = na + 2 * nk;
PyObject **pfunc = stack_pointer - n - 1;
PyObject *func = *pfunc;
- f->f_lasti = INSTR_OFFSET() - 3; /* For tracing */
/* Always dispatch PyCFunction first, because
these are presumed to be the most frequent
@@ -2022,7 +2037,6 @@
n++;
pfunc = stack_pointer - n - 1;
func = *pfunc;
- f->f_lasti = INSTR_OFFSET() - 3; /* For tracing */
if (PyMethod_Check(func)
&& PyMethod_GET_SELF(func) != NULL) {
@@ -2134,7 +2148,8 @@
default:
fprintf(stderr,
"XXX lineno: %d, opcode: %d\n",
- f->f_lineno, opcode);
+ PyCode_Addr2Line(f->f_code, f->f_lasti),
+ opcode);
PyErr_SetString(PyExc_SystemError, "unknown opcode");
why = WHY_EXCEPTION;
break;
@@ -2189,9 +2204,6 @@
/* Log traceback info if this is a real exception */
if (why == WHY_EXCEPTION) {
- f->f_lasti = INSTR_OFFSET() - 1;
- if (HAS_ARG(opcode))
- f->f_lasti -= 2;
PyTraceBack_Here(f);
if (tstate->c_tracefunc != NULL)
@@ -2875,6 +2887,125 @@
return result;
}
+static void
+maybe_call_line_trace(int opcode, Py_tracefunc func, PyObject *obj,
+ PyFrameObject *frame, int *instr_lb, int *instr_ub)
+{
+ /* The theory of SET_LINENO-less tracing.
+
+ In a nutshell, we use the co_lnotab field of the code object
+ to tell when execution has moved onto a different line.
+
+ As mentioned above, the basic idea is so set things up so
+ that
+
+ *instr_lb <= frame->f_lasti < *instr_ub
+
+ is true so long as execution does not change lines.
+
+ This is all fairly simple. Digging the information out of
+ co_lnotab takes some work, but is conceptually clear.
+
+ Somewhat harder to explain is why we don't call the line
+ trace function when executing a POP_TOP or RETURN_NONE
+ opcodes. An example probably serves best.
+
+ Consider this code:
+
+ 1: def f(a):
+ 2: if a:
+ 3: print 1
+ 4: else:
+ 5: print 2
+
+ which compiles to this:
+
+ 2 0 LOAD_FAST 0 (a)
+ 3 JUMP_IF_FALSE 9 (to 15)
+ 6 POP_TOP
+
+ 3 7 LOAD_CONST 1 (1)
+ 10 PRINT_ITEM
+ 11 PRINT_NEWLINE
+ 12 JUMP_FORWARD 6 (to 21)
+ >> 15 POP_TOP
+
+ 5 16 LOAD_CONST 2 (2)
+ 19 PRINT_ITEM
+ 20 PRINT_NEWLINE
+ >> 21 RETURN_NONE
+
+ If a is false, execution will jump to instruction at offset
+ 15 and the co_lnotab will claim that execution has moved to
+ line 3. This is at best misleading. In this case we could
+ associate the POP_TOP with line 4, but that doesn't make
+ sense in all cases (I think).
+
+ On the other hand, if a is true, execution will jump from
+ instruction offset 12 to offset 21. Then the co_lnotab would
+ imply that execution has moved to line 5, which is again
+ misleading.
+
+ This is why it is important that RETURN_NONE is *only* used
+ for the "falling off the end of the function" form of
+ returning None -- using it for code like
+
+ 1: def f():
+ 2: return
+
+ would, once again, lead to misleading tracing behaviour.
+
+ It is also worth mentioning that getting tracing behaviour
+ right is the *entire* motivation for adding the RETURN_NONE
+ opcode.
+ */
+
+ if (opcode != POP_TOP && opcode != RETURN_NONE &&
+ (frame->f_lasti < *instr_lb || frame->f_lasti > *instr_ub)) {
+ PyCodeObject* co = frame->f_code;
+ int size, addr;
+ unsigned char* p;
+
+ call_trace(func, obj, frame, PyTrace_LINE, Py_None);
+
+ size = PyString_Size(co->co_lnotab) / 2;
+ p = (unsigned char*)PyString_AsString(co->co_lnotab);
+
+ /* possible optimization: if f->f_lasti == instr_ub
+ (likely to be a common case) then we already know
+ instr_lb -- if we stored the matching value of p
+ somwhere we could skip the first while loop. */
+
+ addr = 0;
+
+ /* see comments in compile.c for the description of
+ co_lnotab. A point to remember: increments to p
+ should come in pairs -- although we don't care about
+ the line increments here, treating them as byte
+ increments gets confusing, to say the least. */
+
+ while (size >= 0) {
+ if (addr + *p > frame->f_lasti)
+ break;
+ addr += *p++;
+ p++;
+ --size;
+ }
+ *instr_lb = addr;
+ if (size > 0) {
+ while (--size >= 0) {
+ addr += *p++;
+ if (*p++)
+ break;
+ }
+ *instr_ub = addr;
+ }
+ else {
+ *instr_ub = INT_MAX;
+ }
+ }
+}
+
void
PyEval_SetProfile(Py_tracefunc func, PyObject *arg)
{
diff --git a/Python/compile.c b/Python/compile.c
index 5b4e8e6..ff8f4a5 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -407,9 +407,10 @@
/* All about c_lnotab.
-c_lnotab is an array of unsigned bytes disguised as a Python string. In -O
-mode, SET_LINENO opcodes aren't generated, and bytecode offsets are mapped
-to source code line #s (when needed for tracebacks) via c_lnotab instead.
+c_lnotab is an array of unsigned bytes disguised as a Python string. Since
+version 2.3, SET_LINENO opcodes are never generated and bytecode offsets are
+mapped to source code line #s via c_lnotab instead.
+
The array is conceptually a list of
(bytecode offset increment, line number increment)
pairs. The details are important and delicate, best illustrated by example:
@@ -830,11 +831,6 @@
com_addoparg(struct compiling *c, int op, int arg)
{
int extended_arg = arg >> 16;
- if (op == SET_LINENO) {
- com_set_lineno(c, arg);
- if (Py_OptimizeFlag)
- return;
- }
if (extended_arg){
com_addbyte(c, EXTENDED_ARG);
com_addint(c, extended_arg);
@@ -1738,7 +1734,7 @@
break;
if (ch->n_lineno != lineno) {
lineno = ch->n_lineno;
- com_addoparg(c, SET_LINENO, lineno);
+ com_set_lineno(c, lineno);
}
com_argument(c, ch, &keywords);
if (keywords == NULL)
@@ -3168,7 +3164,7 @@
continue;
}
if (i > 0)
- com_addoparg(c, SET_LINENO, ch->n_lineno);
+ com_set_lineno(c, ch->n_lineno);
com_node(c, ch);
com_addfwref(c, JUMP_IF_FALSE, &a);
com_addbyte(c, POP_TOP);
@@ -3195,7 +3191,7 @@
com_addfwref(c, SETUP_LOOP, &break_anchor);
block_push(c, SETUP_LOOP);
c->c_begin = c->c_nexti;
- com_addoparg(c, SET_LINENO, n->n_lineno);
+ com_set_lineno(c, n->n_lineno);
com_node(c, CHILD(n, 1));
com_addfwref(c, JUMP_IF_FALSE, &anchor);
com_addbyte(c, POP_TOP);
@@ -3228,7 +3224,7 @@
com_node(c, CHILD(n, 3));
com_addbyte(c, GET_ITER);
c->c_begin = c->c_nexti;
- com_addoparg(c, SET_LINENO, n->n_lineno);
+ com_set_lineno(c, n->n_lineno);
com_addfwref(c, FOR_ITER, &anchor);
com_push(c, 1);
com_assign(c, CHILD(n, 1), OP_ASSIGN, NULL);
@@ -3339,7 +3335,7 @@
}
except_anchor = 0;
com_push(c, 3); /* tb, val, exc pushed by exception */
- com_addoparg(c, SET_LINENO, ch->n_lineno);
+ com_set_lineno(c, ch->n_lineno);
if (NCH(ch) > 1) {
com_addbyte(c, DUP_TOP);
com_push(c, 1);
@@ -3401,7 +3397,7 @@
com_push(c, 3);
com_backpatch(c, finally_anchor);
ch = CHILD(n, NCH(n)-1);
- com_addoparg(c, SET_LINENO, ch->n_lineno);
+ com_set_lineno(c, ch->n_lineno);
com_node(c, ch);
com_addbyte(c, END_FINALLY);
block_pop(c, END_FINALLY);
@@ -3727,7 +3723,7 @@
case simple_stmt:
/* small_stmt (';' small_stmt)* [';'] NEWLINE */
- com_addoparg(c, SET_LINENO, n->n_lineno);
+ com_set_lineno(c, n->n_lineno);
{
int i;
for (i = 0; i < NCH(n)-1; i += 2)
@@ -3736,7 +3732,7 @@
break;
case compound_stmt:
- com_addoparg(c, SET_LINENO, n->n_lineno);
+ com_set_lineno(c, n->n_lineno);
n = CHILD(n, 0);
goto loop;
@@ -3990,10 +3986,7 @@
c->c_infunction = 1;
com_node(c, CHILD(n, 4));
c->c_infunction = 0;
- com_addoparg(c, LOAD_CONST, com_addconst(c, Py_None));
- com_push(c, 1);
- com_addbyte(c, RETURN_VALUE);
- com_pop(c, 1);
+ com_addbyte(c, RETURN_NONE);
}
static void
@@ -4050,7 +4043,7 @@
static void
compile_node(struct compiling *c, node *n)
{
- com_addoparg(c, SET_LINENO, n->n_lineno);
+ com_set_lineno(c, n->n_lineno);
switch (TYPE(n)) {
@@ -4060,19 +4053,13 @@
n = CHILD(n, 0);
if (TYPE(n) != NEWLINE)
com_node(c, n);
- com_addoparg(c, LOAD_CONST, com_addconst(c, Py_None));
- com_push(c, 1);
- com_addbyte(c, RETURN_VALUE);
- com_pop(c, 1);
+ com_addbyte(c, RETURN_NONE);
c->c_interactive--;
break;
case file_input: /* A whole file, or built-in function exec() */
com_file_input(c, n);
- com_addoparg(c, LOAD_CONST, com_addconst(c, Py_None));
- com_push(c, 1);
- com_addbyte(c, RETURN_VALUE);
- com_pop(c, 1);
+ com_addbyte(c, RETURN_NONE);
break;
case eval_input: /* Built-in function input() */
diff --git a/Python/frozen.c b/Python/frozen.c
index 069ce3c..946d626 100644
--- a/Python/frozen.c
+++ b/Python/frozen.c
@@ -13,12 +13,12 @@
static unsigned char M___hello__[] = {
99,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,
- 0,115,15,0,0,0,127,0,0,127,1,0,100,0,0,71,
- 72,100,1,0,83,40,2,0,0,0,115,14,0,0,0,72,
- 101,108,108,111,32,119,111,114,108,100,46,46,46,78,40,0,
- 0,0,0,40,0,0,0,0,40,0,0,0,0,40,0,0,
- 0,0,115,8,0,0,0,104,101,108,108,111,46,112,121,115,
- 1,0,0,0,63,1,0,0,0,115,0,0,0,0,
+ 0,115,9,0,0,0,100,0,0,71,72,100,1,0,83,40,
+ 2,0,0,0,115,14,0,0,0,72,101,108,108,111,32,119,
+ 111,114,108,100,46,46,46,78,40,0,0,0,0,40,0,0,
+ 0,0,40,0,0,0,0,40,0,0,0,0,115,8,0,0,
+ 0,104,101,108,108,111,46,112,121,115,1,0,0,0,63,1,
+ 0,0,0,115,0,0,0,0,
};
#define SIZE (int)sizeof(M___hello__)
diff --git a/Python/import.c b/Python/import.c
index 6fd05d8..36ca705 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -49,6 +49,9 @@
algorithm relying on the above scheme. Perhaps we should simply
start counting in increments of 10 from now on ?!
+ MWH, 2002-08-03: Removed SET_LINENO. Couldn't be bothered figuring
+ out the MAGIC schemes, so just incremented it by 10.
+
Known values:
Python 1.5: 20121
Python 1.5.1: 20121
@@ -60,8 +63,9 @@
Python 2.1.2: 60202
Python 2.2: 60717
Python 2.3a0: 62011
+ Python 2.3a0: 62021
*/
-#define MAGIC (62011 | ((long)'\r'<<16) | ((long)'\n'<<24))
+#define MAGIC (62021 | ((long)'\r'<<16) | ((long)'\n'<<24))
/* Magic word as global; note that _PyImport_Init() can change the
value of this global to accommodate for alterations of how the
diff --git a/Python/traceback.c b/Python/traceback.c
index de918f9..27c69b6 100644
--- a/Python/traceback.c
+++ b/Python/traceback.c
@@ -103,8 +103,7 @@
};
static tracebackobject *
-newtracebackobject(tracebackobject *next, PyFrameObject *frame, int lasti,
- int lineno)
+newtracebackobject(tracebackobject *next, PyFrameObject *frame)
{
tracebackobject *tb;
if ((next != NULL && !PyTraceBack_Check(next)) ||
@@ -118,8 +117,9 @@
tb->tb_next = next;
Py_XINCREF(frame);
tb->tb_frame = frame;
- tb->tb_lasti = lasti;
- tb->tb_lineno = lineno;
+ tb->tb_lasti = frame->f_lasti;
+ tb->tb_lineno = PyCode_Addr2Line(frame->f_code,
+ frame->f_lasti);
PyObject_GC_Track(tb);
}
return tb;
@@ -130,8 +130,7 @@
{
PyThreadState *tstate = frame->f_tstate;
tracebackobject *oldtb = (tracebackobject *) tstate->curexc_traceback;
- tracebackobject *tb = newtracebackobject(oldtb,
- frame, frame->f_lasti, frame->f_lineno);
+ tracebackobject *tb = newtracebackobject(oldtb, frame);
if (tb == NULL)
return -1;
tstate->curexc_traceback = (PyObject *)tb;
diff --git a/Tools/scripts/trace.py b/Tools/scripts/trace.py
index 9c4819f..f96e04f 100644
--- a/Tools/scripts/trace.py
+++ b/Tools/scripts/trace.py
@@ -370,41 +370,29 @@
except IOError, err:
sys.stderr.write("cannot save counts files because %s" % err)
-# Given a code string, return the SET_LINENO information
-def _find_LINENO_from_string(co_code):
- """return all of the SET_LINENO information from a code string"""
- import dis
+def _find_LINENO_from_code(code):
+ """return the numbers of the lines containing the source code that
+ was compiled into code"""
linenos = {}
- # This code was filched from the `dis' module then modified
- n = len(co_code)
- i = 0
- prev_op = None
- prev_lineno = 0
- while i < n:
- c = co_code[i]
- op = ord(c)
- if op == dis.SET_LINENO:
- if prev_op == op:
- # two SET_LINENO in a row, so the previous didn't
- # indicate anything. This occurs with triple
- # quoted strings (?). Remove the old one.
- del linenos[prev_lineno]
- prev_lineno = ord(co_code[i+1]) + ord(co_code[i+2])*256
- linenos[prev_lineno] = 1
- if op >= dis.HAVE_ARGUMENT:
- i = i + 3
- else:
- i = i + 1
- prev_op = op
+ line_increments = [ord(c) for c in code.co_lnotab[1::2]]
+ table_length = len(line_increments)
+
+ lineno = code.co_first_lineno
+
+ for li in line_increments:
+ linenos[lineno] = 1
+ lineno += li
+ linenos[lineno] = 1
+
return linenos
def _find_LINENO(code):
- """return all of the SET_LINENO information from a code object"""
+ """return all of the lineno information from a code object"""
import types
# get all of the lineno information from the code of this scope level
- linenos = _find_LINENO_from_string(code.co_code)
+ linenos = _find_LINENO_from_code(code)
# and check the constants for references to other code objects
for c in code.co_consts:
@@ -416,9 +404,6 @@
def find_executable_linenos(filename):
"""return a dict of the line numbers from executable statements in a file
- Works by finding all of the code-like objects in the module then searching
- the byte code for 'SET_LINENO' terms (so this won't work one -O files).
-
"""
import parser
@@ -428,10 +413,6 @@
ast = parser.suite(prog)
code = parser.compileast(ast, filename)
- # The only way I know to find line numbers is to look for the
- # SET_LINENO instructions. Isn't there some way to get it from
- # the AST?
-
return _find_LINENO(code)
### XXX because os.path.commonprefix seems broken by my way of thinking...