Re: [PATCH] Fix ICE with -fno-if-conversion (PR rtl-optimization/68730)

[Jakub Jelinek <jakub@redhat.com>]

On Fri, Dec 11, 2015 at 07:30:59AM +0100, Richard Biener wrote:
> >So, to fix ICE on the following testcase, we can either do what the
> >patch
> >does, or could conditionalize both the calculate_dominance_info and
> >free_dominance_info in the convert_scalars_to_vector function (stv
> >pass)
> >on the dominance info not being computed (like other places in gcc do),
> >or we could stick free_dominance_info into all passes that break the
> >dominators just in case it would be computed (out_of_cfglayout is one
> >example).
> 
> We rely on this everywhere else so that would be preferred.

So like this instead?  Bootstrapped/regtested on x86_64-linux and
i686-linux, ok for trunk?

2015-12-10  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/68730
	* cfgrtl.c (cfg_layout_finalize): Free dominators.

	* gcc.dg/pr68730.c: New test.

--- gcc/cfgrtl.c.jj	2015-11-04 11:12:20.000000000 +0100
+++ gcc/cfgrtl.c	2015-12-11 09:34:58.864893607 +0100
@@ -4299,6 +4299,7 @@ void
 cfg_layout_finalize (void)
 {
   checking_verify_flow_info ();
+  free_dominance_info (CDI_DOMINATORS);
   force_one_exit_fallthru ();
   rtl_register_cfg_hooks ();
   if (reload_completed && !targetm.have_epilogue ())
--- gcc/testsuite/gcc.dg/pr68730.c.jj	2015-12-11 09:25:06.022268146 +0100
+++ gcc/testsuite/gcc.dg/pr68730.c	2015-12-11 09:25:06.022268146 +0100
@@ -0,0 +1,51 @@
+/* PR rtl-optimization/68730 */
+/* { dg-do compile } */
+/* { dg-options "-O3 -fno-if-conversion" } */
+/* { dg-additional-options "-march=x86-64" { target { i?86-*-* x86_64-*-* } } } */
+
+int b, d, e;
+unsigned long long c = 4100543410106915;
+
+void
+foo (void)
+{
+  short f, g = 4 % c;
+  int h = c;
+  if (h)
+    {
+      int i = ~c;
+      if (~c)
+	i = 25662;
+      f = g = i;
+      h = c - g + ~-f;
+      c = ~(c * h - f);
+    }
+  f = g;
+  unsigned long long k = g || c;
+  short l = c ^ g ^ k;
+  if (g > 25662 || c == 74074520320 || !(g < 2))
+    {
+      k = c;
+      l = g;
+      c = ~((k && c) + ~l);
+      f = ~(f * (c ^ k) | l);
+      if (c > k)
+	__builtin_printf ("%d\n", f);
+    }
+  short m = -f;
+  unsigned long long n = c;
+  c = m * f | n % c;
+  if (n)
+    __builtin_printf ("%d\n", f);
+  while (f < -31807)
+    ;
+  c = ~(n | c) | f;
+  if (n < c)
+    __builtin_printf ("%lld\n", (long long) f);
+  for (; d;)
+    for (; e;)
+      for (;;)
+	;
+  c = h;
+  c = l % c;
+}


	Jakub