diff options
Diffstat (limited to 'malloc/obstack.h')
| -rw-r--r-- | malloc/obstack.h | 109 |
1 files changed, 62 insertions, 47 deletions
diff --git a/malloc/obstack.h b/malloc/obstack.h index 03f6ccb2ce..206fe55050 100644 --- a/malloc/obstack.h +++ b/malloc/obstack.h @@ -1,8 +1,7 @@ /* obstack.h - object stack macros Copyright (C) 1988-1994,1996-1999,2003,2004,2005 Free Software Foundation, Inc. - This file is part of the GNU C Library. Its master source is NOT part of - the C library, however. The master source lives in /gd/gnu/lib. + This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public @@ -16,8 +15,8 @@ You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free - Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA - 02111-1307 USA. */ + Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + Boston, MA 02110-1301, USA. */ /* Summary: @@ -111,19 +110,7 @@ Summary: extern "C" { #endif -/* We use subtraction of (char *) 0 instead of casting to int - because on word-addressable machines a simple cast to int - may ignore the byte-within-word field of the pointer. */ - -#ifndef __PTR_TO_INT -# define __PTR_TO_INT(P) ((P) - (char *) 0) -#endif - -#ifndef __INT_TO_PTR -# define __INT_TO_PTR(P) ((P) + (char *) 0) -#endif - -/* We need the type of the resulting object. If __PTRDIFF_TYPE__ is +/* We need the type of a pointer subtraction. If __PTRDIFF_TYPE__ is defined, as with GNU C, use that; that way we don't pollute the namespace with <stddef.h>'s symbols. Otherwise, include <stddef.h> and use ptrdiff_t. */ @@ -135,6 +122,23 @@ extern "C" { # define PTR_INT_TYPE ptrdiff_t #endif +/* If B is the base of an object addressed by P, return the result of + aligning P to the next multiple of A + 1. B and P must be of type + char *. A + 1 must be a power of 2. */ + +#define __BPTR_ALIGN(B, P, A) ((B) + (((P) - (B) + (A)) & ~(A))) + +/* Similiar to _BPTR_ALIGN (B, P, A), except optimize the common case + where pointers can be converted to integers, aligned as integers, + and converted back again. If PTR_INT_TYPE is narrower than a + pointer (e.g., the AS/400), play it safe and compute the alignment + relative to B. Otherwise, use the faster strategy of computing the + alignment relative to 0. */ + +#define __PTR_ALIGN(B, P, A) \ + __BPTR_ALIGN (sizeof (PTR_INT_TYPE) < sizeof (void *) ? (B) : (char *) 0, \ + P, A) + #include <string.h> struct _obstack_chunk /* Lives at front of each chunk. */ @@ -151,7 +155,11 @@ struct obstack /* control current object in current chunk */ char *object_base; /* address of object we are building */ char *next_free; /* where to add next char to current object */ char *chunk_limit; /* address of char after current chunk */ - PTR_INT_TYPE temp; /* Temporary for some macros. */ + union + { + PTR_INT_TYPE tempint; + void *tempptr; + } temp; /* Temporary for some macros. */ int alignment_mask; /* Mask of alignment for each object. */ /* These prototypes vary based on `use_extra_arg', and we use casts to the prototypeless function type in all assignments, @@ -276,7 +284,10 @@ __extension__ \ # define obstack_empty_p(OBSTACK) \ __extension__ \ ({ struct obstack const *__o = (OBSTACK); \ - (__o->chunk->prev == 0 && __o->next_free - __o->chunk->contents == 0); }) + (__o->chunk->prev == 0 \ + && __o->next_free == __PTR_ALIGN ((char *) __o->chunk, \ + __o->chunk->contents, \ + __o->alignment_mask)); }) # define obstack_grow(OBSTACK,where,length) \ __extension__ \ @@ -375,8 +386,8 @@ __extension__ \ if (__o1->next_free == __value) \ __o1->maybe_empty_object = 1; \ __o1->next_free \ - = __INT_TO_PTR ((__PTR_TO_INT (__o1->next_free)+__o1->alignment_mask)\ - & ~ (__o1->alignment_mask)); \ + = __PTR_ALIGN (__o1->object_base, __o1->next_free, \ + __o1->alignment_mask); \ if (__o1->next_free - (char *)__o1->chunk \ > __o1->chunk_limit - (char *)__o1->chunk) \ __o1->next_free = __o1->chunk_limit; \ @@ -400,7 +411,10 @@ __extension__ \ (unsigned) ((h)->chunk_limit - (h)->next_free) # define obstack_empty_p(h) \ - ((h)->chunk->prev == 0 && (h)->next_free - (h)->chunk->contents == 0) + ((h)->chunk->prev == 0 \ + && (h)->next_free == __PTR_ALIGN ((char *) (h)->chunk, \ + (h)->chunk->contents, \ + (h)->alignment_mask)) /* Note that the call to _obstack_newchunk is enclosed in (..., 0) so that we can avoid having void expressions @@ -409,23 +423,23 @@ __extension__ \ but some compilers won't accept it. */ # define obstack_make_room(h,length) \ -( (h)->temp = (length), \ - (((h)->next_free + (h)->temp > (h)->chunk_limit) \ - ? (_obstack_newchunk ((h), (h)->temp), 0) : 0)) +( (h)->temp.tempint = (length), \ + (((h)->next_free + (h)->temp.tempint > (h)->chunk_limit) \ + ? (_obstack_newchunk ((h), (h)->temp.tempint), 0) : 0)) # define obstack_grow(h,where,length) \ -( (h)->temp = (length), \ - (((h)->next_free + (h)->temp > (h)->chunk_limit) \ - ? (_obstack_newchunk ((h), (h)->temp), 0) : 0), \ - memcpy ((h)->next_free, where, (h)->temp), \ - (h)->next_free += (h)->temp) +( (h)->temp.tempint = (length), \ + (((h)->next_free + (h)->temp.tempint > (h)->chunk_limit) \ + ? (_obstack_newchunk ((h), (h)->temp.tempint), 0) : 0), \ + memcpy ((h)->next_free, where, (h)->temp.tempint), \ + (h)->next_free += (h)->temp.tempint) # define obstack_grow0(h,where,length) \ -( (h)->temp = (length), \ - (((h)->next_free + (h)->temp + 1 > (h)->chunk_limit) \ - ? (_obstack_newchunk ((h), (h)->temp + 1), 0) : 0), \ - memcpy ((h)->next_free, where, (h)->temp), \ - (h)->next_free += (h)->temp, \ +( (h)->temp.tempint = (length), \ + (((h)->next_free + (h)->temp.tempint + 1 > (h)->chunk_limit) \ + ? (_obstack_newchunk ((h), (h)->temp.tempint + 1), 0) : 0), \ + memcpy ((h)->next_free, where, (h)->temp.tempint), \ + (h)->next_free += (h)->temp.tempint, \ *((h)->next_free)++ = 0) # define obstack_1grow(h,datum) \ @@ -450,10 +464,10 @@ __extension__ \ (((int *) ((h)->next_free += sizeof (int)))[-1] = (aint)) # define obstack_blank(h,length) \ -( (h)->temp = (length), \ - (((h)->chunk_limit - (h)->next_free < (h)->temp) \ - ? (_obstack_newchunk ((h), (h)->temp), 0) : 0), \ - obstack_blank_fast (h, (h)->temp)) +( (h)->temp.tempint = (length), \ + (((h)->chunk_limit - (h)->next_free < (h)->temp.tempint) \ + ? (_obstack_newchunk ((h), (h)->temp.tempint), 0) : 0), \ + obstack_blank_fast (h, (h)->temp.tempint)) # define obstack_alloc(h,length) \ (obstack_blank ((h), (length)), obstack_finish ((h))) @@ -468,22 +482,23 @@ __extension__ \ ( ((h)->next_free == (h)->object_base \ ? (((h)->maybe_empty_object = 1), 0) \ : 0), \ - (h)->temp = __PTR_TO_INT ((h)->object_base), \ + (h)->temp.tempptr = (h)->object_base, \ (h)->next_free \ - = __INT_TO_PTR ((__PTR_TO_INT ((h)->next_free)+(h)->alignment_mask) \ - & ~ ((h)->alignment_mask)), \ + = __PTR_ALIGN ((h)->object_base, (h)->next_free, \ + (h)->alignment_mask), \ (((h)->next_free - (char *) (h)->chunk \ > (h)->chunk_limit - (char *) (h)->chunk) \ ? ((h)->next_free = (h)->chunk_limit) : 0), \ (h)->object_base = (h)->next_free, \ - (void *) __INT_TO_PTR ((h)->temp)) + (h)->temp.tempptr) # define obstack_free(h,obj) \ -( (h)->temp = (char *) (obj) - (char *) (h)->chunk, \ - (((h)->temp > 0 && (h)->temp < (h)->chunk_limit - (char *) (h)->chunk)\ +( (h)->temp.tempint = (char *) (obj) - (char *) (h)->chunk, \ + ((((h)->temp.tempint > 0 \ + && (h)->temp.tempint < (h)->chunk_limit - (char *) (h)->chunk)) \ ? (int) ((h)->next_free = (h)->object_base \ - = (h)->temp + (char *) (h)->chunk) \ - : (((obstack_free) ((h), (h)->temp + (char *) (h)->chunk), 0), 0))) + = (h)->temp.tempint + (char *) (h)->chunk) \ + : (((obstack_free) ((h), (h)->temp.tempint + (char *) (h)->chunk), 0), 0))) #endif /* not __GNUC__ or not __STDC__ */ |