]> git.ipfire.org Git - thirdparty/gcc.git/commit
i386: Fix ICE caused by ix86_emit_i387_log1p [PR105214]
authorJakub Jelinek <jakub@redhat.com>
Tue, 12 Apr 2022 07:19:11 +0000 (09:19 +0200)
committerJakub Jelinek <jakub@redhat.com>
Wed, 13 Apr 2022 04:28:00 +0000 (06:28 +0200)
commit5b87d9f50b421e18be2a4ef95548182c8af2891e
treea0adfcad2975f93fa19eb2ca40d9ce0966fdce3d
parent1e4dd03e3a39c65aa5d75df7dd51f4b7fbcc8daa
i386: Fix ICE caused by ix86_emit_i387_log1p [PR105214]

The following testcase ICEs, because ix86_emit_i387_log1p attempts to
emit something like
  if (cond)
    some_code1;
  else
    some_code2;
and emits a conditional jump using emit_jump_insn (standard way in
the file) and an unconditional jump using emit_jump.
The problem with that is that if there is pending stack adjustment,
it isn't emitted before the conditional jump, but is before the
unconditional jump and therefore stack is adjusted only conditionally
(at the end of some_code1 above), which makes dwarf2 pass unhappy about it
but is a serious wrong-code even if it doesn't ICE.

This can be fixed either by emitting pending stack adjust before the
conditional jump as the following patch does, or by not using
  emit_jump (label2);
and instead hand inlining what that function does except for the
pending stack adjustment, like:
  emit_jump_insn (targetm.gen_jump (label2));
  emit_barrier ();
In that case there will be no stack adjustment in the sequence and
it will be done later on somewhere else.

2022-04-12  Jakub Jelinek  <jakub@redhat.com>

PR target/105214
* config/i386/i386-expand.c (ix86_emit_i387_log1p): Call
do_pending_stack_adjust.

* gcc.dg/asan/pr105214.c: New test.

(cherry picked from commit d481d13786cb84f6294833538133dbd6f39d2e55)
gcc/config/i386/i386-expand.c
gcc/testsuite/gcc.dg/asan/pr105214.c [new file with mode: 0644]