removed alloca.c which is now in libiberty
This commit is contained in:
K. Richard Pixley
parent
8860783950
commit
fbca751901
2 changed files with 2 additions and 191 deletions
|
|
@ -1,5 +1,7 @@
|
|||
Wed Jun 23 15:04:54 1993 K. Richard Pixley (rich@sendai.cygnus.com)
|
||||
|
||||
* alloca.c: removed. alloca is now in libiberty.
|
||||
|
||||
* config/m88k/delta88.mh, config/ns32k/merlin.mh (M_UNINSTALL):
|
||||
new macro to undo what M_INSTALL does.
|
||||
|
||||
|
|
|
|||
191
gdb/alloca.c
191
gdb/alloca.c
|
|
@ -1,191 +0,0 @@
|
|||
/*
|
||||
alloca -- (mostly) portable public-domain implementation -- D A Gwyn
|
||||
|
||||
last edit: 86/05/30 rms
|
||||
include config.h, since on VMS it renames some symbols.
|
||||
Use xmalloc instead of malloc.
|
||||
|
||||
This implementation of the PWB library alloca() function,
|
||||
which is used to allocate space off the run-time stack so
|
||||
that it is automatically reclaimed upon procedure exit,
|
||||
was inspired by discussions with J. Q. Johnson of Cornell.
|
||||
|
||||
It should work under any C implementation that uses an
|
||||
actual procedure stack (as opposed to a linked list of
|
||||
frames). There are some preprocessor constants that can
|
||||
be defined when compiling for your specific system, for
|
||||
improved efficiency; however, the defaults should be okay.
|
||||
|
||||
The general concept of this implementation is to keep
|
||||
track of all alloca()-allocated blocks, and reclaim any
|
||||
that are found to be deeper in the stack than the current
|
||||
invocation. This heuristic does not reclaim storage as
|
||||
soon as it becomes invalid, but it will do so eventually.
|
||||
|
||||
As a special case, alloca(0) reclaims storage without
|
||||
allocating any. It is a good idea to use alloca(0) in
|
||||
your main control loop, etc. to force garbage collection.
|
||||
*/
|
||||
#ifndef lint
|
||||
static char SCCSid[] = "@(#)alloca.c 1.1"; /* for the "what" utility */
|
||||
#endif
|
||||
|
||||
#ifdef emacs
|
||||
#include "config.h"
|
||||
#ifdef static
|
||||
/* actually, only want this if static is defined as ""
|
||||
-- this is for usg, in which emacs must undefine static
|
||||
in order to make unexec workable
|
||||
*/
|
||||
#ifndef STACK_DIRECTION
|
||||
you
|
||||
lose
|
||||
-- must know STACK_DIRECTION at compile-time
|
||||
#endif /* STACK_DIRECTION undefined */
|
||||
#endif /* static */
|
||||
#endif /* emacs */
|
||||
|
||||
#ifdef __STDC__
|
||||
typedef void *pointer; /* generic pointer type */
|
||||
#else
|
||||
typedef char *pointer; /* generic pointer type */
|
||||
#endif
|
||||
|
||||
#define NULL 0 /* null pointer constant */
|
||||
|
||||
extern void free();
|
||||
extern pointer xmalloc();
|
||||
|
||||
/*
|
||||
Define STACK_DIRECTION if you know the direction of stack
|
||||
growth for your system; otherwise it will be automatically
|
||||
deduced at run-time.
|
||||
|
||||
STACK_DIRECTION > 0 => grows toward higher addresses
|
||||
STACK_DIRECTION < 0 => grows toward lower addresses
|
||||
STACK_DIRECTION = 0 => direction of growth unknown
|
||||
*/
|
||||
|
||||
#ifndef STACK_DIRECTION
|
||||
#define STACK_DIRECTION 0 /* direction unknown */
|
||||
#endif
|
||||
|
||||
#if STACK_DIRECTION != 0
|
||||
|
||||
#define STACK_DIR STACK_DIRECTION /* known at compile-time */
|
||||
|
||||
#else /* STACK_DIRECTION == 0; need run-time code */
|
||||
|
||||
static int stack_dir; /* 1 or -1 once known */
|
||||
#define STACK_DIR stack_dir
|
||||
|
||||
static void
|
||||
find_stack_direction (/* void */)
|
||||
{
|
||||
static char *addr = NULL; /* address of first
|
||||
`dummy', once known */
|
||||
auto char dummy; /* to get stack address */
|
||||
|
||||
if (addr == NULL)
|
||||
{ /* initial entry */
|
||||
addr = &dummy;
|
||||
|
||||
find_stack_direction (); /* recurse once */
|
||||
}
|
||||
else /* second entry */
|
||||
if (&dummy > addr)
|
||||
stack_dir = 1; /* stack grew upward */
|
||||
else
|
||||
stack_dir = -1; /* stack grew downward */
|
||||
}
|
||||
|
||||
#endif /* STACK_DIRECTION == 0 */
|
||||
|
||||
/*
|
||||
An "alloca header" is used to:
|
||||
(a) chain together all alloca()ed blocks;
|
||||
(b) keep track of stack depth.
|
||||
|
||||
It is very important that sizeof(header) agree with malloc()
|
||||
alignment chunk size. The following default should work okay.
|
||||
*/
|
||||
|
||||
#ifndef ALIGN_SIZE
|
||||
#define ALIGN_SIZE sizeof(double)
|
||||
#endif
|
||||
|
||||
typedef union hdr
|
||||
{
|
||||
char align[ALIGN_SIZE]; /* to force sizeof(header) */
|
||||
struct
|
||||
{
|
||||
union hdr *next; /* for chaining headers */
|
||||
char *deep; /* for stack depth measure */
|
||||
} h;
|
||||
} header;
|
||||
|
||||
/*
|
||||
alloca( size ) returns a pointer to at least `size' bytes of
|
||||
storage which will be automatically reclaimed upon exit from
|
||||
the procedure that called alloca(). Originally, this space
|
||||
was supposed to be taken from the current stack frame of the
|
||||
caller, but that method cannot be made to work for some
|
||||
implementations of C, for example under Gould's UTX/32.
|
||||
*/
|
||||
|
||||
static header *last_alloca_header = NULL; /* -> last alloca header */
|
||||
|
||||
pointer
|
||||
alloca (size) /* returns pointer to storage */
|
||||
unsigned size; /* # bytes to allocate */
|
||||
{
|
||||
auto char probe; /* probes stack depth: */
|
||||
register char *depth = &probe;
|
||||
|
||||
#if STACK_DIRECTION == 0
|
||||
if (STACK_DIR == 0) /* unknown growth direction */
|
||||
find_stack_direction ();
|
||||
#endif
|
||||
|
||||
/* Reclaim garbage, defined as all alloca()ed storage that
|
||||
was allocated from deeper in the stack than currently. */
|
||||
|
||||
{
|
||||
register header *hp; /* traverses linked list */
|
||||
|
||||
for (hp = last_alloca_header; hp != NULL;)
|
||||
if ( (STACK_DIR > 0 && hp->h.deep > depth)
|
||||
|| (STACK_DIR < 0 && hp->h.deep < depth) )
|
||||
{
|
||||
register header *np = hp->h.next;
|
||||
|
||||
free ((pointer) hp); /* collect garbage */
|
||||
|
||||
hp = np; /* -> next header */
|
||||
}
|
||||
else
|
||||
break; /* rest are not deeper */
|
||||
|
||||
last_alloca_header = hp; /* -> last valid storage */
|
||||
}
|
||||
|
||||
if (size == 0)
|
||||
return NULL; /* no allocation required */
|
||||
|
||||
/* Allocate combined header + user data storage. */
|
||||
|
||||
{
|
||||
register pointer new = xmalloc (sizeof (header) + size);
|
||||
/* address of header */
|
||||
|
||||
((header *)new)->h.next = last_alloca_header;
|
||||
((header *)new)->h.deep = depth;
|
||||
|
||||
last_alloca_header = (header *)new;
|
||||
|
||||
/* User storage begins just after header. */
|
||||
|
||||
return (pointer)((char *)new + sizeof(header));
|
||||
}
|
||||
}
|
||||
|
||||
Loading…
Reference in a new issue