On Wed, Dec 13, 2017 at 03:25:07PM +0100, Jakub Jelinek wrote:
> I think there are 2 issues. One is that the ia64 backend emits
> the group barrier insns before BB_HEAD label, so it isn't part of a bb,
> but has BLOCK_FOR_INSN of the following block, that looks invalid to me
> and the ia64.c hunk ought to fix that, except that I don't have access to
> ia64 anymore and so can't test it. Andreas, could you try that?
>
> Another thing is that if we because of this end up with insns outside of
> basic blocks, the vt_initialize asserts will fire again. Here, first of
> all, IMNSHO we should assert that debug bind insns aren't outside of basic
> blocks, the other patches and checking should ensure that (and if any slips
> in, we want to fix that too rather than work-around).
> Another is that while walking from get_first_insn to one before BB_HEAD
> (bb->next_bb),
> we can encounter insns outside of bb not just before BB_HEAD (bb), but also
> after BB_END (bb), both cases are outside of a bb and thus we can
> expect BLOCK_FOR_INSN being NULL.
>
> Bootstrapped/regtested on x86_64-linux, i686-linux, powerpc64le-linux,
> regtest on powerpc64-linux pending. Ok for trunk perhaps without the
> ia64.c bits until that gets tested?
>
> Or, in the PR there is a variant patch which just doesn't do the asserts and
> doesn't have to track outside_bb.
Here is another variant, without trying to change ia64 backend which
apparently doesn't bootstrap for other reasons.
This patch instead ignores insns outside of basic blocks during var-tracking
exactly as it has been ignoring them before, and just processes the debug
begin stmt markers in there (and verifies no debug bind stmts appear in
between bbs).
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2017-12-13 Jakub Jelinek <ja...@redhat.com>
PR bootstrap/83396
* var-tracking.c (vt_initialize): Ignore non-DEBUG_INSNs outside of
basic blocks. Assert debug bind insns don't appear outside of bbs,
don't reset them. Assert insns without BLOCK_FOR_INSN are outside of
bb. Simplify.
* gcc.dg/pr83396.c: New test.
--- gcc/var-tracking.c.jj 2017-12-13 13:22:59.651783152 +0100
+++ gcc/var-tracking.c 2017-12-13 19:11:13.895699735 +0100
@@ -10157,25 +10157,31 @@ vt_initialize (void)
insns that might be before it too. Unfortunately,
BB_HEADER and BB_FOOTER are not set while we run this
pass. */
- insn = get_first_insn (bb);
- for (rtx_insn *next;
- insn != BB_HEAD (bb->next_bb)
- ? next = NEXT_INSN (insn), true : false;
+ rtx_insn *next;
+ bool outside_bb = true;
+ for (insn = get_first_insn (bb); insn != BB_HEAD (bb->next_bb);
insn = next)
{
+ if (insn == BB_HEAD (bb))
+ outside_bb = false;
+ else if (insn == NEXT_INSN (BB_END (bb)))
+ outside_bb = true;
+ next = NEXT_INSN (insn);
if (INSN_P (insn))
{
+ if (outside_bb)
+ {
+ /* Ignore non-debug insns outside of basic blocks. */
+ if (!DEBUG_INSN_P (insn))
+ continue;
+ /* Debug binds shouldn't appear outside of bbs. */
+ gcc_assert (!DEBUG_BIND_INSN_P (insn));
+ }
basic_block save_bb = BLOCK_FOR_INSN (insn);
if (!BLOCK_FOR_INSN (insn))
{
+ gcc_assert (outside_bb);
BLOCK_FOR_INSN (insn) = bb;
- gcc_assert (DEBUG_INSN_P (insn));
- /* Reset debug insns between basic blocks.
- Their location is not reliable, because they
- were probably not maintained up to date. */
- if (DEBUG_BIND_INSN_P (insn))
- INSN_VAR_LOCATION_LOC (insn)
- = gen_rtx_UNKNOWN_VAR_LOC ();
}
else
gcc_assert (BLOCK_FOR_INSN (insn) == bb);
--- gcc/testsuite/gcc.dg/pr83396.c.jj 2017-12-13 15:53:15.446687005 +0100
+++ gcc/testsuite/gcc.dg/pr83396.c 2017-12-13 15:53:15.446687005 +0100
@@ -0,0 +1,12 @@
+/* PR bootstrap/83396 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -g" } */
+
+int bar (int);
+int baz (int);
+
+int
+foo (int x)
+{
+ return bar (x) || baz (x) != 0;
+}
Jakub
