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(DONT_COPY_FLAG): Default this to 1.

Browse source 
(mark_object): Use the same XOR expression as elsewhere.
(gc_sweep): Don't touch DONT_COPY_FLAG here; this one is a real size field,
not a mangled pointer.
This commit is contained in:
Karl Heuer 1995-01-13 00:00:23 +00:00
parent ea9e39a024
commit 1fb577f7e5
1 changed files with 13 additions and 9 deletions
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22
src/alloc.c
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@ -107,10 +107,15 @@ Lisp_Object memory_signal_data;
#define MAX_SAVE_STACK 16000
#endif
/* Define DONT_COPY_FLAG to be the bit in a small string that was placed
in the low bit of the size field when marking small strings. */
/* Define DONT_COPY_FLAG to be some bit which will always be zero in a
pointer to a Lisp_Object, when that pointer is viewed as an integer.
(On most machines, pointers are even, so we can use the low bit.
Word-addressible architectures may need to override this in the m-file.)
When linking references to small strings through the size field, we
use this slot to hold the bit that would otherwise be interpreted as
the GC mark bit. */
#ifndef DONT_COPY_FLAG
#define DONT_COPY_FLAG PSEUDOVECTOR_FLAG
#define DONT_COPY_FLAG 1
#endif /* no DONT_COPY_FLAG */
/* Buffer in which we save a copy of the C stack at each GC. */
@ -1509,8 +1514,7 @@ mark_object (objptr)
{
/* A small string. Put this reference
into the chain of references to it.
The address OBJPTR is even, so if the address
includes MARKBIT, put it in the low bit
If the address includes MARKBIT, put that bit elsewhere
when we store OBJPTR into the size field. */
if (XMARKBIT (*objptr))
@ -1523,9 +1527,9 @@ mark_object (objptr)
if ((EMACS_INT) objptr & DONT_COPY_FLAG)
abort ();
ptr->size = (EMACS_INT) objptr & ~MARKBIT;
if ((EMACS_INT) objptr & MARKBIT)
ptr->size |= DONT_COPY_FLAG;
ptr->size = (EMACS_INT) objptr;
if (ptr->size & MARKBIT)
ptr->size ^= MARKBIT | DONT_COPY_FLAG;
}
}
break;
@ -2043,7 +2047,7 @@ gc_sweep ()
if (s->size & ARRAY_MARK_FLAG)
{
((struct Lisp_String *)(&sb->chars[0]))->size
&= ~ARRAY_MARK_FLAG & ~MARKBIT & ~DONT_COPY_FLAG;
&= ~ARRAY_MARK_FLAG & ~MARKBIT;
UNMARK_BALANCE_INTERVALS (s->intervals);
total_string_size += ((struct Lisp_String *)(&sb->chars[0]))->size;
prev = sb, sb = sb->next;