Message ID | alpine.LNX.2.20.13.1902282043500.30425@monopod.intra.ispras.ru |
---|---|
State | New |
Headers | show |
Series | haifa-sched: handle fallthru edge to EXIT block (PR 85899) | expand |
On Thu, 28 Feb 2019, Alexander Monakov wrote: > Hi, > > in PR 85899 an assert is failing in find_fallthru_edge_from because the code > tries to verify the invariant e->dest == e->src->next_bb for a fallthru edge > and does not anticipate that it will fail if e->dest is the exit block (bb 1): > in this case next_bb is fairly arbitrary (it's just the next bb that appears > in the insn sequence and has nothing to do with the "fake" fallthru to exit). Or is the bug in out-of-cfglayout code creating such bogus fallthru edge? Thanks. Alexander
> So it looks to me that the assert has to allow this. I've bootstrapped the > following (not that it matters much as it simply relaxes the assert) and > verified it fixes the testcase. Yes, fallthrough edges to the exit block exist in RTL, see could_fall_through. > OK for trunk? > > * haifa-sched.c (find_fallthru_edge_from): Relax assert to account for > fallthru edges leading to the exit block. > > * gcc.dg/pr85899.c: New test. OK, thanks.
diff --git a/gcc/haifa-sched.c b/gcc/haifa-sched.c index 72178b68999..5025aae421d 100644 --- a/gcc/haifa-sched.c +++ b/gcc/haifa-sched.c @@ -8082,7 +8082,7 @@ find_fallthru_edge_from (basic_block pred) if (e) { - gcc_assert (e->dest == succ); + gcc_assert (e->dest == succ || e->dest->index == EXIT_BLOCK); return e; } } diff --git a/gcc/testsuite/gcc.dg/pr85899.c b/gcc/testsuite/gcc.dg/pr85899.c index e69de29bb2d..eb2b175339c 100644 --- a/gcc/testsuite/gcc.dg/pr85899.c +++ b/gcc/testsuite/gcc.dg/pr85899.c @@ -0,0 +1,17 @@ +/* { dg-do compile { target powerpc*-*-* ia64-*-* i?86-*-* x86_64-*-* } } */ +/* { dg-options "-O2 -fschedule-insns -fselective-scheduling -funroll-loops -fno-gcse -fno-if-conversion -fno-ivopts" } */ + +#define N 4096 +int cb[N]; +int cc[N]; +int cd[N]; + +void init () +{ + int i; + for (i = 0; i < N; ++i) { + cb[i] = 3 * i - 2048; + cc[i] = -5 * i + 93; + cd[i] = i % 2 ? 1 : -1; + } +}