public inbox for gcc-cvs@sourceware.org help / color / mirror / Atom feed
From: J?rgen Kvalsvik <jkv@gcc.gnu.org> To: gcc-cvs@gcc.gnu.org Subject: [gcc r14-9870] Guard function->cond_uids access [PR114601] Date: Tue, 9 Apr 2024 11:49:03 +0000 (GMT) [thread overview] Message-ID: <20240409114903.ECBCA385842A@sourceware.org> (raw) https://gcc.gnu.org/g:dd78e6a3cbd8f7c678d90ca0d05787faeb2e9c9a commit r14-9870-gdd78e6a3cbd8f7c678d90ca0d05787faeb2e9c9a Author: Jørgen Kvalsvik <j@lambda.is> Date: Tue Apr 9 13:39:03 2024 +0200 Guard function->cond_uids access [PR114601] PR114601 shows that it is possible to reach the condition_uid lookup without having also created the fn->cond_uids, through compiler-generated conditionals. Consider all lookups on non-existing maps misses, which they are from the perspective of the source code, to avoid the NULL access. PR gcov-profile/114601 gcc/ChangeLog: * tree-profile.cc (condition_uid): Guard fn->cond_uids access. gcc/testsuite/ChangeLog: * gcc.misc-tests/gcov-pr114601.c: New test. Diff: --- gcc/testsuite/gcc.misc-tests/gcov-pr114601.c | 11 +++++++++++ gcc/tree-profile.cc | 9 +++++++-- 2 files changed, 18 insertions(+), 2 deletions(-) diff --git a/gcc/testsuite/gcc.misc-tests/gcov-pr114601.c b/gcc/testsuite/gcc.misc-tests/gcov-pr114601.c new file mode 100644 index 00000000000..72248c8fd25 --- /dev/null +++ b/gcc/testsuite/gcc.misc-tests/gcov-pr114601.c @@ -0,0 +1,11 @@ +/* PR gcov-profile/114601 */ +/* { dg-do compile } */ +/* { dg-options "-fcondition-coverage -finstrument-functions-once" } */ + +/* -finstrument-functions-once inserts a hidden conditional expression into + this function which otherwise has none. This caused a crash on looking up + the condition as the cond->expr map is not created unless it necessary. */ +void +empty (void) +{ +} diff --git a/gcc/tree-profile.cc b/gcc/tree-profile.cc index b85111624fe..b87c121790c 100644 --- a/gcc/tree-profile.cc +++ b/gcc/tree-profile.cc @@ -359,12 +359,17 @@ condition_index (unsigned flag) min-max, etc., which leaves ghost identifiers in basic blocks that do not end with a conditional jump. They are not really meaningful for condition coverage anymore, but since coverage is unreliable under optimization anyway - this is not a big problem. */ + this is not a big problem. + + The cond_uids map in FN cannot be expected to exist. It will only be + created if it is needed, and a function may have gconds even though there + are none in source. This can be seen in PR gcov-profile/114601, when + -finstrument-functions-once is used and the function has no conditions. */ unsigned condition_uid (struct function *fn, basic_block b) { gimple *stmt = gsi_stmt (gsi_last_bb (b)); - if (!safe_is_a<gcond *> (stmt)) + if (!safe_is_a <gcond*> (stmt) || !fn->cond_uids) return 0; unsigned *v = fn->cond_uids->get (as_a <gcond*> (stmt));
reply other threads:[~2024-04-09 11:49 UTC|newest] Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20240409114903.ECBCA385842A@sourceware.org \ --to=jkv@gcc.gnu.org \ --cc=gcc-cvs@gcc.gnu.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).