+2002-08-22 Zack Weinberg <zack@codesourcery.com>
+
+ * ggc-page.c: Avoid division in ggc_set_mark.
+ (DIV_MULT, DIV_SHIFT, OFFSET_TO_BIT, inverse_table,
+ compute_inverse): New.
+ (ggc_set_mark, ggc_marked_p): Use OFFSET_TO_BIT.
+ (init_ggc): Initialize inverse_table.
+
2002-08-22 Tom Tromey <tromey@redhat.com>
* doc/install.texi (Configuration): Document --datadir.
* config/rs6000/rs6000.c: Ditto.
* config/stormy16/stormy16.h: Ditto.
* doc/md.texi: Ditto.
-
+
2002-08-21 John David Anglin <dave@hiauly1.hia.nrc.ca>
* cppinit.c (remove_dup_nonsys_dirs): Fix warning and return value.
errors.
2002-08-21 Andrew Pinski <pinskia@physics.uc.edu>
- Kaveh R. Ghazi <ghazi@caip.rutgers.edu>
+ Kaveh R. Ghazi <ghazi@caip.rutgers.edu>
* doc/tm.texi (TARGET_ASM_GLOBALIZE_LABEL): Move '@end deftypefn'
to the actual end. Add '@end table' and '@table @code'.
-
+
2002-08-20 Geoffrey Keating <geoffk@redhat.com>
* doc/tm.texi (Label Output): Add missing '@end deftypefn'.
2002-08-20 Devang Patel <dpatel@apple.com>
* tree.c (get_qualified_type): Add TYPE_CONTEXT check.
-
+
2002-08-20 Kaveh R. Ghazi <ghazi@caip.rutgers.edu>
* arc.c (output_shift): Use stdio instead of asm_fprintf.
(mips_use_dfa_pipeline_interface): Use.
2002-08-15 Eric Christopher <echristo@redhat.com>
- Richard Sandiford <rsandifo@redhat.com>
+ Richard Sandiford <rsandifo@redhat.com>
Aldy Hernandez <aldyh@redhat.com>
Graham Stott <grahams@redhat.com>
Michael Meissner <meissner@redhat.com>
quote and bracket include chains when they duplicate equivalent system
directories.
* doc/cpp.texi (-I): Update.
- * doc/cppopts.texi (-I): Update.
- * doc/install.texi (--with-local-prefix): Further document usage of
+ * doc/cppopts.texi (-I): Update.
+ * doc/install.texi (--with-local-prefix): Further document usage of
this option.
* doc/invoke.texi (-I): Update.
2002-08-14 Dale Johannesen <dalej@apple.com>
- * explow.c (emit_stack_restore): Emit memory clobbers
+ * explow.c (emit_stack_restore): Emit memory clobbers
preceding the stack pop, to prevent the scheduler from
moving refs to variable arrays below this pop.
* reload1.c (reload): Preserve these clobbers for sched2.
2002-08-13 Denis Chertykov <denisc@overta.ru>
* config/avr/avr.md: Call CC_STATUS_INIT in all peepnoles
- which can change CC0.
+ which can change CC0.
Tue Aug 13 14:49:20 2002 J"orn Rennecke <joern.rennecke@superh.com>
2002-08-06 Aldy Hernandez <aldyh@redhat.com>
- * c-decl.c (duplicate_decls): Error out for incompatible TLS
- declarations.
+ * c-decl.c (duplicate_decls): Error out for incompatible TLS
+ declarations.
- * testsuite/gcc.dg/tls/diag-3.c: New.
+ * testsuite/gcc.dg/tls/diag-3.c: New.
2002-08-06 Jason Merrill <jason@redhat.com>
2002-08-06 Dale Johannesen <dalej@apple.com>
* c-common.c (fname_decl): Use line number 0 for
- __func__, to avoid confusing debuggers.
+ __func__, to avoid confusing debuggers.
2002-08-06 Nathan Sidwell <nathan@codesourcery.com>
/* The size of an object on a page of the indicated ORDER. */
#define OBJECT_SIZE(ORDER) object_size_table[ORDER]
+/* For speed, we avoid doing a general integer divide to locate the
+ offset in the allocation bitmap, by precalculating numbers M, S
+ such that (O * M) >> S == O / Z (modulo 2^32), for any offset O
+ within the page which is evenly divisible by the object size Z. */
+#define DIV_MULT(ORDER) inverse_table[ORDER].mult
+#define DIV_SHIFT(ORDER) inverse_table[ORDER].shift
+#define OFFSET_TO_BIT(OFFSET, ORDER) \
+ (((OFFSET) * DIV_MULT (ORDER)) >> DIV_SHIFT (ORDER))
+
/* The number of extra orders, not corresponding to power-of-two sized
objects. */
static size_t object_size_table[NUM_ORDERS];
+/* The Ith entry is a pair of numbers (mult, shift) such that
+ ((k * mult) >> shift) mod 2^32 == (k / OBJECT_SIZE(I)) mod 2^32,
+ for all k evenly divisible by OBJECT_SIZE(I). */
+
+static struct
+{
+ unsigned int mult;
+ unsigned int shift;
+}
+inverse_table[NUM_ORDERS];
+
/* A page_entry records the status of an allocation page. This
structure is dynamically sized to fit the bitmap in_use_p. */
typedef struct page_entry
static void clear_marks PARAMS ((void));
static void sweep_pages PARAMS ((void));
static void ggc_recalculate_in_use_p PARAMS ((page_entry *));
+static void compute_inverse PARAMS ((unsigned));
#ifdef GGC_POISON
static void poison_pages PARAMS ((void));
/* Calculate the index of the object on the page; this is its bit
position in the in_use_p bitmap. */
- bit = (((const char *) p) - entry->page) / OBJECT_SIZE (entry->order);
+ bit = OFFSET_TO_BIT (((const char *) p) - entry->page, entry->order);
word = bit / HOST_BITS_PER_LONG;
mask = (unsigned long) 1 << (bit % HOST_BITS_PER_LONG);
/* Calculate the index of the object on the page; this is its bit
position in the in_use_p bitmap. */
- bit = (((const char *) p) - entry->page) / OBJECT_SIZE (entry->order);
+ bit = OFFSET_TO_BIT (((const char *) p) - entry->page, entry->order);
word = bit / HOST_BITS_PER_LONG;
mask = (unsigned long) 1 << (bit % HOST_BITS_PER_LONG);
return OBJECT_SIZE (pe->order);
}
\f
-/* Initialize the ggc-mmap allocator. */
+/* Subroutine of init_ggc which computes the pair of numbers used to
+ perform division by OBJECT_SIZE (order) and fills in inverse_table[].
+
+ This algorithm is taken from Granlund and Montgomery's paper
+ "Division by Invariant Integers using Multiplication"
+ (Proc. SIGPLAN PLDI, 1994), section 9 (Exact division by
+ constants). */
+
+static void
+compute_inverse (order)
+ unsigned order;
+{
+ unsigned size, inv, e;
+
+ size = OBJECT_SIZE (order);
+ e = 0;
+ while (size % 2 == 0)
+ {
+ e++;
+ size >>= 1;
+ }
+ inv = size;
+ while (inv * size != 1)
+ inv = inv * (2 - inv*size);
+
+ DIV_MULT (order) = inv;
+ DIV_SHIFT (order) = e;
+}
+
+/* Initialize the ggc-mmap allocator. */
void
init_ggc ()
{
object_size_table[order] = s;
}
- /* Initialize the objects-per-page table. */
+ /* Initialize the objects-per-page and inverse tables. */
for (order = 0; order < NUM_ORDERS; ++order)
{
objects_per_page_table[order] = G.pagesize / OBJECT_SIZE (order);
if (objects_per_page_table[order] == 0)
objects_per_page_table[order] = 1;
+ compute_inverse (order);
}
/* Reset the size_lookup array to put appropriately sized objects in
git://gcc.gnu.org / gcc.git / commitdiff