From da4eb5c3b55df9b7d6957ddd0458313102f0a92e Mon Sep 17 00:00:00 2001 From: Guido van Rossum Date: Fri, 24 Jan 1997 03:43:35 +0000 Subject: [PATCH] Instead of emitting SET_LINENO instructions, generate a line number table which is incorporated in the code object. This way, the runtime overhead to keep track of line numbers is only incurred when an exception has to be reported. --- Python/compile.c | 108 ++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 102 insertions(+), 6 deletions(-) diff --git a/Python/compile.c b/Python/compile.c index 6d3a479f49c..e06f345358e 100644 --- a/Python/compile.c +++ b/Python/compile.c @@ -76,6 +76,8 @@ static struct memberlist code_memberlist[] = { {"co_varnames", T_OBJECT, OFF(co_varnames), READONLY}, {"co_filename", T_OBJECT, OFF(co_filename), READONLY}, {"co_name", T_OBJECT, OFF(co_name), READONLY}, + {"co_firstlineno", T_INT, OFF(co_firstlineno), READONLY}, + {"co_lnotab", T_OBJECT, OFF(co_lnotab), READONLY}, {NULL} /* Sentinel */ }; @@ -180,7 +182,8 @@ typeobject Codetype = { codeobject * newcodeobject(argcount, nlocals, stacksize, flags, - code, consts, names, varnames, filename, name) + code, consts, names, varnames, filename, name, + firstlineno, lnotab) int argcount; int nlocals; int stacksize; @@ -191,6 +194,8 @@ newcodeobject(argcount, nlocals, stacksize, flags, object *varnames; object *filename; object *name; + int firstlineno; + object *lnotab; { codeobject *co; int i; @@ -201,7 +206,8 @@ newcodeobject(argcount, nlocals, stacksize, flags, names == NULL || !is_tupleobject(names) || varnames == NULL || !is_tupleobject(varnames) || name == NULL || !is_stringobject(name) || - filename == NULL || !is_stringobject(filename)) { + filename == NULL || !is_stringobject(filename) || + lnotab == NULL || !is_stringobject(lnotab)) { err_badcall(); return NULL; } @@ -252,6 +258,9 @@ newcodeobject(argcount, nlocals, stacksize, flags, co->co_filename = filename; INCREF(name); co->co_name = name; + co->co_firstlineno = firstlineno; + INCREF(lnotab); + co->co_lnotab = lnotab; } return co; } @@ -282,6 +291,9 @@ struct compiling { int c_lineno; /* Current line number */ int c_stacklevel; /* Current stack level */ int c_maxstacklevel; /* Maximum stack level */ + int c_firstlineno; + object *c_lnotab; /* Table mapping address to line number */ + int c_last_addr, c_last_line, c_lnotab_next; #ifdef PRIVATE_NAME_MANGLING char *c_private; /* for private name mangling */ #endif @@ -387,6 +399,8 @@ com_init(c, filename) goto fail_00; if ((c->c_varnames = newlistobject(0)) == NULL) goto fail_000; + if ((c->c_lnotab = newsizedstringobject((char *)NULL, 1000)) == NULL) + goto fail_0000; c->c_nlocals = 0; c->c_argcount = 0; c->c_flags = 0; @@ -402,8 +416,14 @@ com_init(c, filename) c->c_lineno = 0; c->c_stacklevel = 0; c->c_maxstacklevel = 0; + c->c_firstlineno = 0; + c->c_last_addr = 0; + c->c_last_line = 0; + c-> c_lnotab_next = 0; return 1; + fail_0000: + DECREF(c->c_lnotab); fail_000: DECREF(c->c_locals); fail_00: @@ -428,6 +448,7 @@ com_free(c) XDECREF(c->c_globals); XDECREF(c->c_locals); XDECREF(c->c_varnames); + XDECREF(c->c_lnotab); } static void @@ -462,6 +483,8 @@ com_done(c) { if (c->c_code != NULL) resizestring(&c->c_code, c->c_nexti); + if (c->c_lnotab != NULL) + resizestring(&c->c_lnotab, c->c_lnotab_next); } static void @@ -499,6 +522,57 @@ com_addint(c, x) com_addbyte(c, x >> 8); /* XXX x should be positive */ } +static void +com_add_lnotab(c, addr, line) + struct compiling *c; + int addr; + int line; +{ + int size; + char *p; + if (c->c_lnotab == NULL) + return; + size = getstringsize(c->c_lnotab); + if (c->c_lnotab_next+2 > size) { + if (resizestring(&c->c_lnotab, size + 1000) < 0) { + c->c_errors++; + return; + } + } + p = getstringvalue(c->c_lnotab) + c->c_lnotab_next; + *p++ = addr; + *p++ = line; + c->c_lnotab_next += 2; +} + +static void +com_set_lineno(c, lineno) + struct compiling *c; + int lineno; +{ + c->c_lineno = lineno; + if (c->c_firstlineno == 0) { + c->c_firstlineno = c->c_last_line = lineno; + } + else { + int incr_addr = c->c_nexti - c->c_last_addr; + int incr_line = lineno - c->c_last_line; + while (incr_addr > 0 || incr_line > 0) { + int trunc_addr = incr_addr; + int trunc_line = incr_line; + if (trunc_addr > 255) + trunc_addr = 255; + if (trunc_line > 255) + trunc_line = 255; + com_add_lnotab(c, trunc_addr, trunc_line); + incr_addr -= trunc_addr; + incr_line -= trunc_line; + } + c->c_last_addr = c->c_nexti; + c->c_last_line = lineno; + } +} + static void com_addoparg(c, op, arg) struct compiling *c; @@ -506,9 +580,11 @@ com_addoparg(c, op, arg) int arg; { if (op == SET_LINENO) - c->c_lineno = arg; - com_addbyte(c, op); - com_addint(c, arg); + com_set_lineno(c, arg); + else { + com_addbyte(c, op); + com_addint(c, arg); + } } static void @@ -3212,7 +3288,9 @@ jcompile(n, filename, base) names, varnames, filename, - name); + name, + sc.c_firstlineno, + sc.c_lnotab); XDECREF(consts); XDECREF(names); XDECREF(varnames); @@ -3222,3 +3300,21 @@ jcompile(n, filename, base) com_free(&sc); return co; } + +int +PyCode_Addr2Line(co, addrq) + PyCodeObject *co; + int addrq; +{ + int size = PyString_Size(co->co_lnotab) / 2; + char *p = PyString_AsString(co->co_lnotab); + int line = co->co_firstlineno; + int addr = 0; + while (--size >= 0) { + addr += *p++; + if (addr > addrq) + break; + line += *p++; + } + return line; +}