[PATCH 05/12] Convert the unavailable to be bit based.

Andrew Burgess
2013-08-12T12:24:06Z

The unavailable vector currently stores byte ranges within the value.
However, the optimized out interface allows for bit ranges to be
optimized out.

This patch changes the unavailable vector to be bit based, and at the
same time moves the code that actually inserts into the vector into a
helper function.

OK to apply?

Thanks,
Andrew

gdb/ChangeLog

2013-08-12 Andrew Burgess <aburgess@broadcom.com>

* value.c (insert_into_bit_range_vector): New function for
inserting into the vector.
(mark_value_bytes_unavailable): Use new function to build
the unavailable vector in bits rather than bytes.
(value_available_contents_eq): Take account of parameters being
bytes, but the unavailable range now being in bits.
(value_contents_copy_raw): Likewise, change to accommodate the
unavailable vector being in bits.
(value_bytes_available): Convert byte values to bits.

diff --git a/gdb/value.c b/gdb/value.c
index 64c9d78..e28c213 100644
--- a/gdb/value.c
+++ b/gdb/value.c
@@ -337,7 +337,9 @@ value_bytes_available (const struct value *value,
int offset
{
gdb_assert (!value->lazy);
- return !ranges_contain (value->unavailable, offset, length);
+ return !ranges_contain (value->unavailable,
+ offset * TARGET_CHAR_BIT,
+ length * TARGET_CHAR_BIT);
}
int
@@ -353,8 +353,11 @@ value_entirely_available (struct value *value)
return 0;
}
-void
-mark_value_bytes_unavailable (struct value *value, int offset, int length)
+/* Insert into the vector pointed to by VECTORP the bit range starting of
+ OFFSET bits, and extending for the next LENGTH bits. */
+
+static void
+insert_into_bit_range_vector (VEC(range_s) **vectorp, int offset, int
length)
{
range_s newr;
int i;
@@ -445,10 +448,10 @@ mark_value_bytes_unavailable (struct value *value,
int offset, int length)
*/
- i = VEC_lower_bound (range_s, value->unavailable, &newr,
range_lessthan);
+ i = VEC_lower_bound (range_s, *vectorp, &newr, range_lessthan);
if (i > 0)
{
- struct range *bef = VEC_index (range_s, value->unavailable, i - 1);
+ struct range *bef = VEC_index (range_s, *vectorp, i - 1);
if (ranges_overlap (bef->offset, bef->length, offset, length))
{
@@ -469,18 +472,18 @@ mark_value_bytes_unavailable (struct value *value,
int offset, int length)
else
{
/* #3 */
- VEC_safe_insert (range_s, value->unavailable, i, &newr);
+ VEC_safe_insert (range_s, *vectorp, i, &newr);
}
}
else
{
/* #4 */
- VEC_safe_insert (range_s, value->unavailable, i, &newr);
+ VEC_safe_insert (range_s, *vectorp, i, &newr);
}
/* Check whether the ranges following the one we've just added or
touched can be folded in (#5 above). */
- if (i + 1 < VEC_length (range_s, value->unavailable))
+ if (i + 1 < VEC_length (range_s, *vectorp))
{
struct range *t;
struct range *r;
@@ -488,11 +491,11 @@ mark_value_bytes_unavailable (struct value *value,
int offset, int length)
int next = i + 1;
/* Get the range we just touched. */
- t = VEC_index (range_s, value->unavailable, i);
+ t = VEC_index (range_s, *vectorp, i);
removed = 0;
i = next;
- for (; VEC_iterate (range_s, value->unavailable, i, r); i++)
+ for (; VEC_iterate (range_s, *vectorp, i, r); i++)
if (r->offset <= t->offset + t->length)
{
ULONGEST l, h;
@@ -514,10 +517,18 @@ mark_value_bytes_unavailable (struct value *value,
int offset, int length)
}
if (removed != 0)
- VEC_block_remove (range_s, value->unavailable, next, removed);
+ VEC_block_remove (range_s, *vectorp, next, removed);
}
}
+void
+mark_value_bytes_unavailable (struct value *value, int offset, int length)
+{
+ insert_into_bit_range_vector (&value->unavailable,
+ offset * TARGET_CHAR_BIT,
+ length * TARGET_CHAR_BIT);
+}
+
/* Find the first range in RANGES that overlaps the range defined by
OFFSET and LENGTH, starting at element POS in the RANGES vector,
Returns the index into RANGES where such overlapping range was
@@ -547,6 +558,12 @@ value_available_contents_eq (const struct value
*val1, int offset1,
/* See function description in value.h. */
gdb_assert (!val1->lazy && !val2->lazy);
+ /* The offsets and length parameters are all byte based, but we
store the
+ unavailable data in a bit based list. */
+ offset1 *= TARGET_CHAR_BIT;
+ offset2 *= TARGET_CHAR_BIT;
+ length *= TARGET_CHAR_BIT;
+
while (length > 0)
{
range_s *r1, *r2;
@@ -560,9 +577,9 @@ value_available_contents_eq (const struct value
*val1, int offset1,
/* The usual case is for both values to be completely available. */
if (idx1 == -1 && idx2 == -1)
- return (memcmp (val1->contents + offset1,
- val2->contents + offset2,
- length) == 0);
+ return (memcmp (val1->contents + (offset1 / TARGET_CHAR_BIT),
+ val2->contents + (offset2 / TARGET_CHAR_BIT),
+ (length / TARGET_CHAR_BIT)) == 0);
/* The contents only match equal if the available set matches as
well. */
else if (idx1 == -1 || idx2 == -1)
@@ -595,9 +612,9 @@ value_available_contents_eq (const struct value
*val1, int offset1,
return 0;
/* Compare the _available_ contents. */
- if (memcmp (val1->contents + offset1,
- val2->contents + offset2,
- l1) != 0)
+ if (memcmp (val1->contents + (offset1 / TARGET_CHAR_BIT),
+ val2->contents + (offset2 / TARGET_CHAR_BIT),
+ (l1 / TARGET_CHAR_BIT)) != 0)
return 0;
length -= h1;
@@ -938,6 +955,7 @@ value_contents_copy_raw (struct value *dst, int
dst_offset,
{
range_s *r;
int i;
+ int src_bit_offset, dst_bit_offset, bit_length;
/* A lazy DST would make that this copy operation useless, since as
soon as DST's contents were un-lazied (by a later value_contents
@@ -956,16 +974,19 @@ value_contents_copy_raw (struct value *dst, int
dst_offset,
length);
/* Copy the meta-data, adjusted. */
+ src_bit_offset = src_offset * TARGET_CHAR_BIT;
+ dst_bit_offset = dst_offset * TARGET_CHAR_BIT;
+ bit_length = length * TARGET_CHAR_BIT;
for (i = 0; VEC_iterate (range_s, src->unavailable, i, r); i++)
{
ULONGEST h, l;
- l = max (r->offset, src_offset);
- h = min (r->offset + r->length, src_offset + length);
+ l = max (r->offset, src_bit_offset);
+ h = min (r->offset + r->length, src_bit_offset + bit_length);
if (l < h)
- mark_value_bytes_unavailable (dst,
- dst_offset + (l - src_offset),
+ insert_into_bit_range_vector (&dst->unavailable,
+ dst_bit_offset + (l - src_bit_offset),
h - l);
}
}