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-rw-r--r--gcc/bitmap.c25
1 files changed, 19 insertions, 6 deletions
diff --git a/gcc/bitmap.c b/gcc/bitmap.c
index 97e60de..4fabdc9 100644
--- a/gcc/bitmap.c
+++ b/gcc/bitmap.c
@@ -595,9 +595,9 @@ bitmap_find_bit (bitmap head, unsigned int bit)
return element;
}
-/* Clear a single bit in a bitmap. */
+/* Clear a single bit in a bitmap. Return true if the bit changed. */
-void
+bool
bitmap_clear_bit (bitmap head, int bit)
{
bitmap_element *const ptr = bitmap_find_bit (head, bit);
@@ -606,17 +606,24 @@ bitmap_clear_bit (bitmap head, int bit)
{
unsigned bit_num = bit % BITMAP_WORD_BITS;
unsigned word_num = bit / BITMAP_WORD_BITS % BITMAP_ELEMENT_WORDS;
- ptr->bits[word_num] &= ~ (((BITMAP_WORD) 1) << bit_num);
+ BITMAP_WORD bit_val = ((BITMAP_WORD) 1) << bit_num;
+ bool res = (ptr->bits[word_num] & bit_val) != 0;
+ if (res)
+ ptr->bits[word_num] &= ~bit_val;
/* If we cleared the entire word, free up the element. */
if (bitmap_element_zerop (ptr))
bitmap_element_free (head, ptr);
+
+ return res;
}
+
+ return false;
}
-/* Set a single bit in a bitmap. */
+/* Set a single bit in a bitmap. Return true if the bit changed. */
-void
+bool
bitmap_set_bit (bitmap head, int bit)
{
bitmap_element *ptr = bitmap_find_bit (head, bit);
@@ -630,9 +637,15 @@ bitmap_set_bit (bitmap head, int bit)
ptr->indx = bit / BITMAP_ELEMENT_ALL_BITS;
ptr->bits[word_num] = bit_val;
bitmap_element_link (head, ptr);
+ return true;
}
else
- ptr->bits[word_num] |= bit_val;
+ {
+ bool res = (ptr->bits[word_num] & bit_val) == 0;
+ if (res)
+ ptr->bits[word_num] |= bit_val;
+ return res;
+ }
}
/* Return whether a bit is set within a bitmap. */