diff --git a/gcc/bitmap.cc b/gcc/bitmap.cc
index 20de562caac07d2716ff96a1a61ded3ed8dc32c1..d1d0324b633e7a118a53e6861bee97bf8ba8bf91 100644
--- a/gcc/bitmap.cc
+++ b/gcc/bitmap.cc
@@ -1217,12 +1217,12 @@ bitmap_single_bit_set_p (const_bitmap a)
/* Return the bit number of the first set bit in the bitmap. The
- bitmap must be non-empty. */
+ bitmap must be non-empty. When CLEAR is true it clears the bit. */
-unsigned
-bitmap_first_set_bit (const_bitmap a)
+static unsigned
+bitmap_first_set_bit_worker (bitmap a, bool clear)
{
- const bitmap_element *elt = a->first;
+ bitmap_element *elt = a->first;
unsigned bit_no;
BITMAP_WORD word;
unsigned ix;
@@ -1269,9 +1269,42 @@ bitmap_first_set_bit (const_bitmap a)
gcc_checking_assert (word & 1);
#endif
+
+ if (clear)
+ {
+ elt->bits[ix] &= ~((BITMAP_WORD) 1 << (bit_no % BITMAP_WORD_BITS));
+ /* If we cleared the entire word, free up the element. */
+ if (!elt->bits[ix]
+ && bitmap_element_zerop (elt))
+ {
+ if (!a->tree_form)
+ bitmap_list_unlink_element (a, elt);
+ else
+ bitmap_tree_unlink_element (a, elt);
+ }
+ }
+
return bit_no;
}
+/* Return the bit number of the first set bit in the bitmap. The
+ bitmap must be non-empty. */
+
+unsigned
+bitmap_first_set_bit (const_bitmap a)
+{
+ return bitmap_first_set_bit_worker (const_cast<bitmap> (a), false);
+}
+
+/* Return and clear the bit number of the first set bit in the bitmap. The
+ bitmap must be non-empty. */
+
+unsigned
+bitmap_clear_first_set_bit (bitmap a)
+{
+ return bitmap_first_set_bit_worker (a, true);
+}
+
/* Return the bit number of the first set bit in the bitmap. The
bitmap must be non-empty. */
diff --git a/gcc/bitmap.h b/gcc/bitmap.h
index 43337d2e9d9ed8c1be2c230221f2c8e7204d9f8f..5432f386dbd4509bcf2bc4780f7dba8cc43e56fd 100644
--- a/gcc/bitmap.h
+++ b/gcc/bitmap.h
@@ -110,6 +110,7 @@ along with GCC; see the file COPYING3. If not see
* clear : bitmap_clear
* smallest_member : bitmap_first_set_bit
+ * pop_smallest : bitmap_clear_first_set_bit
* choose_one : (not implemented, but could be
in constant time)
@@ -133,6 +134,7 @@ along with GCC; see the file COPYING3. If not see
amortized time with O(E) worst-case behavior.
* smallest_member
+ * pop_smallest
* largest_member
* set_size
* member_p
@@ -501,6 +503,7 @@ extern void debug (const bitmap_head &ref);
extern void debug (const bitmap_head *ptr);
extern unsigned bitmap_first_set_bit (const_bitmap);
+extern unsigned bitmap_clear_first_set_bit (bitmap);
extern unsigned bitmap_last_set_bit (const_bitmap);
/* Compute bitmap hash (for purposes of hashing etc.) */
diff --git a/gcc/df-core.cc b/gcc/df-core.cc
index 38f69ac57431381ac569b3761bb36a6ab84f3a74..3286ffda2ce82f0e0b5a5d5cbcb79fa2c7fad360 100644
--- a/gcc/df-core.cc
+++ b/gcc/df-core.cc
@@ -1040,8 +1040,7 @@ df_worklist_dataflow_doublequeue (struct dataflow *dataflow,
do
{
- unsigned index = bitmap_first_set_bit (worklist);
- bitmap_clear_bit (worklist, index);
+ unsigned index = bitmap_clear_first_set_bit (worklist);
unsigned bb_index;
dcount++;
diff --git a/gcc/graphite-scop-detection.cc b/gcc/graphite-scop-detection.cc
index f976451949d4d0dfa372c58ba4fca9776ec6dffd..99551990e5445f583439d43920e6d4a1a94f5c88 100644
--- a/gcc/graphite-scop-detection.cc
+++ b/gcc/graphite-scop-detection.cc
@@ -469,8 +469,7 @@ scop_detection::merge_sese (sese_l first, sese_l second) const
its border it acts more like a visited bitmap. */
do
{
- int index = bitmap_first_set_bit (worklist);
- bitmap_clear_bit (worklist, index);
+ int index = bitmap_clear_first_set_bit (worklist);
basic_block bb = BASIC_BLOCK_FOR_FN (cfun, index);
edge_iterator ei;
edge e;
diff --git a/gcc/sanopt.cc b/gcc/sanopt.cc
index 85489739507e43fc3b8fe463f14cc1f7a6ee9e96..ce8393b951872e571aed77b6a8a6806f21607a9c 100644
--- a/gcc/sanopt.cc
+++ b/gcc/sanopt.cc
@@ -1012,8 +1012,7 @@ sanitize_asan_mark_unpoison (void)
/* 2) Propagate the information to all reachable blocks. */
while (!bitmap_empty_p (worklist))
{
- unsigned i = bitmap_first_set_bit (worklist);
- bitmap_clear_bit (worklist, i);
+ unsigned i = bitmap_clear_first_set_bit (worklist);
basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i);
gcc_assert (bb);
@@ -1109,8 +1108,7 @@ sanitize_asan_mark_poison (void)
/* 2) Propagate the information to all definitions blocks. */
while (!bitmap_empty_p (worklist))
{
- unsigned i = bitmap_first_set_bit (worklist);
- bitmap_clear_bit (worklist, i);
+ unsigned i = bitmap_clear_first_set_bit (worklist);
basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i);
gcc_assert (bb);
diff --git a/gcc/tree-cfgcleanup.cc b/gcc/tree-cfgcleanup.cc
index 64ff16fc45bab5a91e6b1e05cb4651c3aede28b0..42b253121220251c630fb27a564af51ed59698fb 100644
--- a/gcc/tree-cfgcleanup.cc
+++ b/gcc/tree-cfgcleanup.cc
@@ -1133,8 +1133,7 @@ cleanup_tree_cfg_noloop (unsigned ssa_update_flags)
/* Now process the altered blocks, as long as any are available. */
while (!bitmap_empty_p (cfgcleanup_altered_bbs))
{
- unsigned i = bitmap_first_set_bit (cfgcleanup_altered_bbs);
- bitmap_clear_bit (cfgcleanup_altered_bbs, i);
+ unsigned i = bitmap_clear_first_set_bit (cfgcleanup_altered_bbs);
if (i < NUM_FIXED_BLOCKS)
continue;
diff --git a/gcc/tree-into-ssa.cc b/gcc/tree-into-ssa.cc
index 2e3229904565117faa8d2581beceaa6a552c5ea6..5cfe7c516cc95b9d9f6c38cc7a9ad31826cb0803 100644
--- a/gcc/tree-into-ssa.cc
+++ b/gcc/tree-into-ssa.cc
@@ -2348,8 +2348,7 @@ rewrite_blocks (basic_block entry, enum rewrite_mode what)
}
while (!bitmap_empty_p (worklist))
{
- int idx = bitmap_first_set_bit (worklist);
- bitmap_clear_bit (worklist, idx);
+ int idx = bitmap_clear_first_set_bit (worklist);
basic_block bb = BASIC_BLOCK_FOR_FN (cfun, idx);
bb->flags |= in_region;
extra_rgn.safe_push (bb);
diff --git a/gcc/tree-ssa-dce.cc b/gcc/tree-ssa-dce.cc
index 0ae998f86f9839ba5a95c5fc1a22cd2f12b5cdad..bda780876f3afd3a69351699f7a58c423ed997ed 100644
--- a/gcc/tree-ssa-dce.cc
+++ b/gcc/tree-ssa-dce.cc
@@ -2102,8 +2102,7 @@ simple_dce_from_worklist (bitmap worklist)
while (! bitmap_empty_p (worklist))
{
/* Pop item. */
- unsigned i = bitmap_first_set_bit (worklist);
- bitmap_clear_bit (worklist, i);
+ unsigned i = bitmap_clear_first_set_bit (worklist);
tree def = ssa_name (i);
/* Removed by somebody else or still in use. */
diff --git a/gcc/tree-ssa-sccvn.cc b/gcc/tree-ssa-sccvn.cc
index 9692911e31b2567f112aa97f5a7e2e94112f5b4b..7fa2a154e840c115fd225e6848fef951c49186f0 100644
--- a/gcc/tree-ssa-sccvn.cc
+++ b/gcc/tree-ssa-sccvn.cc
@@ -8491,8 +8491,7 @@ do_rpo_vn_1 (function *fn, edge entry, bitmap exit_bbs,
bitmap_set_bit (worklist, 0);
while (!bitmap_empty_p (worklist))
{
- int idx = bitmap_first_set_bit (worklist);
- bitmap_clear_bit (worklist, idx);
+ int idx = bitmap_clear_first_set_bit (worklist);
basic_block bb = BASIC_BLOCK_FOR_FN (fn, rpo[idx]);
gcc_assert ((bb->flags & BB_EXECUTABLE)
&& !rpo_state[idx].visited);