https://gcc.gnu.org/g:0fe35e9b93a286de78dd5b80d8d58e9ef0591f03
commit r15-7067-g0fe35e9b93a286de78dd5b80d8d58e9ef0591f03
Author: Andrew Pinski <quic_apin...@quicinc.com>
Date: Sun Jan 19 16:07:10 2025 -0800
inline: Purge the abnormal edges as needed in fold_marked_statements
[PR118077]
While fixing PR target/117665, I had noticed that fold_marked_statements
would not purge the abnormal edges which could not be taken any more due
to folding a call (devirtualization or simplification of a [target]
builtin).
Devirutalization could also cause a call that used to be able to have an
abornal edge become one not needing one too so this was needed for GCC 15.
Bootstrapped and tested on x86_64-linux-gnu
PR tree-optimization/118077
PR tree-optimization/117668
gcc/ChangeLog:
* tree-inline.cc (fold_marked_statements): Purge abnormal edges
as needed.
gcc/testsuite/ChangeLog:
* g++.dg/opt/devirt6.C: New test.
Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com>
Diff:
---
gcc/testsuite/g++.dg/opt/devirt6.C | 23 +++++++++++++++++++++++
gcc/tree-inline.cc | 22 ++++++++++++++++++++--
2 files changed, 43 insertions(+), 2 deletions(-)
diff --git a/gcc/testsuite/g++.dg/opt/devirt6.C
b/gcc/testsuite/g++.dg/opt/devirt6.C
new file mode 100644
index 000000000000..5caf9da78910
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/devirt6.C
@@ -0,0 +1,23 @@
+// { dg-do compile { target c++11 } }
+// { dg-options "-O3" }
+
+// PR tree-optimization/118077
+
+// This used to ICE because the devirtualization call
+// of bb inside f1 (which was inlined into f2) became
+// a direct call to c1::bb but the abnormal edge
+// was not removed even though bb was const.
+
+int f() __attribute__((returns_twice));
+struct c1 {
+ virtual int bb(void) const { return 0; }
+ bool f1(int a)
+ {
+ return a && !bb();
+ }
+};
+struct c2 final : c1 { void f2(int); };
+void c2::f2(int a) {
+ if (!f1(a))
+ f();
+}
diff --git a/gcc/tree-inline.cc b/gcc/tree-inline.cc
index 11278e5c4832..5b3539009a38 100644
--- a/gcc/tree-inline.cc
+++ b/gcc/tree-inline.cc
@@ -5430,6 +5430,7 @@ static void
fold_marked_statements (int first, hash_set<gimple *> *statements)
{
auto_bitmap to_purge;
+ auto_bitmap to_purge_abnormal;
auto_vec<edge, 20> stack (n_basic_blocks_for_fn (cfun) + 2);
auto_sbitmap visited (last_basic_block_for_fn (cfun));
@@ -5456,8 +5457,16 @@ fold_marked_statements (int first, hash_set<gimple *>
*statements)
continue;
gimple *old_stmt = gsi_stmt (gsi);
- tree old_decl = (is_gimple_call (old_stmt)
- ? gimple_call_fndecl (old_stmt) : 0);
+ bool can_make_abnormal_goto = false;
+ tree old_decl = NULL_TREE;
+
+ if (is_gimple_call (old_stmt))
+ {
+ old_decl = gimple_call_fndecl (old_stmt);
+ if (stmt_can_make_abnormal_goto (old_stmt))
+ can_make_abnormal_goto = true;
+ }
+
if (old_decl && fndecl_built_in_p (old_decl))
{
/* Folding builtins can create multiple instructions,
@@ -5473,6 +5482,8 @@ fold_marked_statements (int first, hash_set<gimple *>
*statements)
{
cgraph_update_edges_for_call_stmt (old_stmt,
old_decl, NULL);
+ if (can_make_abnormal_goto)
+ bitmap_set_bit (to_purge_abnormal, dest->index);
break;
}
if (gsi_end_p (i2))
@@ -5501,6 +5512,9 @@ fold_marked_statements (int first, hash_set<gimple *>
*statements)
if (maybe_clean_or_replace_eh_stmt (old_stmt,
new_stmt))
bitmap_set_bit (to_purge, dest->index);
+ if (can_make_abnormal_goto
+ && !stmt_can_make_abnormal_goto (new_stmt))
+ bitmap_set_bit (to_purge_abnormal, dest->index);
break;
}
gsi_next (&i2);
@@ -5521,6 +5535,9 @@ fold_marked_statements (int first, hash_set<gimple *>
*statements)
if (maybe_clean_or_replace_eh_stmt (old_stmt, new_stmt))
bitmap_set_bit (to_purge, dest->index);
+ if (can_make_abnormal_goto
+ && !stmt_can_make_abnormal_goto (new_stmt))
+ bitmap_set_bit (to_purge_abnormal, dest->index);
}
}
@@ -5542,6 +5559,7 @@ fold_marked_statements (int first, hash_set<gimple *>
*statements)
}
gimple_purge_all_dead_eh_edges (to_purge);
+ gimple_purge_all_dead_abnormal_call_edges (to_purge_abnormal);
}
/* Expand calls to inline functions in the body of FN. */
