make-dfsg/dep.h
Paul Smith 49ee105c68 Fix performance degradation introduced by the second expansion feature.
I did this by adding intelligence into the algorithm such that the
second expansion was only actually performed when the prerequisite list
contained at least one "$", so we knew it is actually needed.

Without this we were using up a LOT more memory, since every single
target (even ones never used by make) had their file variables
initialized.  This also used a lot more CPU, since we needed to create
and populate a new variable hash table for every target.

There is one issue remaining with this feature: it leaks memory.  In
pattern_search() we now initialize the file variables for every pattern
target, which allocates a hash table, etc.  However, sometimes we
recursively invoke pattern_search() (for intermediate files) with an
automatic variable (alloca() I believe) as the file.  When that function
returns, obviously, the file variable hash memory is lost.
2005-04-13 03:16:33 +00:00

80 lines
2.7 KiB
C

/* Definitions of dependency data structures for GNU Make.
Copyright (C) 1988, 1989, 1991, 1992, 1993, 1996 Free Software Foundation, Inc.
This file is part of GNU Make.
GNU Make is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU Make is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU Make; see the file COPYING. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/* Flag bits for the second argument to `read_makefile'.
These flags are saved in the `changed' field of each
`struct dep' in the chain returned by `read_all_makefiles'. */
#define RM_NO_DEFAULT_GOAL (1 << 0) /* Do not set default goal. */
#define RM_INCLUDED (1 << 1) /* Search makefile search path. */
#define RM_DONTCARE (1 << 2) /* No error if it doesn't exist. */
#define RM_NO_TILDE (1 << 3) /* Don't expand ~ in file name. */
#define RM_NOFLAG 0
/* Structure representing one dependency of a file.
Each struct file's `deps' points to a chain of these,
chained through the `next'.
Note that the first two words of this match a struct nameseq. */
struct dep
{
struct dep *next;
char *name;
struct file *file;
unsigned int changed : 8;
unsigned int ignore_mtime : 1;
unsigned int need_2nd_expansion : 1;
};
/* Structure used in chains of names, for parsing and globbing. */
struct nameseq
{
struct nameseq *next;
char *name;
};
extern struct nameseq *multi_glob PARAMS ((struct nameseq *chain, unsigned int size));
#ifdef VMS
extern struct nameseq *parse_file_seq ();
#else
extern struct nameseq *parse_file_seq PARAMS ((char **stringp, int stopchar, unsigned int size, int strip));
#endif
extern char *tilde_expand PARAMS ((char *name));
#ifndef NO_ARCHIVES
extern struct nameseq *ar_glob PARAMS ((char *arname, char *member_pattern, unsigned int size));
#endif
#ifndef iAPX286
#define dep_name(d) ((d)->name == 0 ? (d)->file->name : (d)->name)
#else
/* Buggy compiler can't hack this. */
extern char *dep_name ();
#endif
extern struct dep *copy_dep_chain PARAMS ((struct dep *d));
extern void free_ns_chain PARAMS ((struct nameseq *n));
extern struct dep *read_all_makefiles PARAMS ((char **makefiles));
extern int eval_buffer PARAMS ((char *buffer));
extern int update_goal_chain PARAMS ((struct dep *goals));
extern void uniquize_deps PARAMS ((struct dep *));