On Tue, Jul 18, 2017 at 9:31 AM, Richard Biener
<richard.guent...@gmail.com> wrote:
> On Tue, Jul 18, 2017 at 10:00 AM, Bin Cheng <bin.ch...@arm.com> wrote:
>> Hi,
>> I removed unsafe loop optimization on TREE level last year, so GCC doesn't
>> do unsafe
>> loop optimizations on TREE now. All "unsafe loop optimizations" warnings
>> reported by
>> TREE optimizers are simply missed optimizations. This patch turns such
>> warning into
>> missed optimization messages. I didn't change when this will be dumped, for
>> now it is
>> when called from ivopts.
>> Bootstrap and test on x86_64 and AArch64. Is it OK?
>
> Ok but can you change the testcase to not scan the ivopts dump but use
> -fopt-info-loop-missed?
> You should be able to match the output with dg-message.
Thanks for reviewing. New patch with test case updated accordingly. Is it OK?
Thanks,
bin
>
> Thanks,
> Richard.
>
>> Thanks,
>> bin
>> 2017-07-13 Bin Cheng <bin.ch...@arm.com>
>>
>> PR target/81408
>> * tree-ssa-loop-niter.c (number_of_iterations_exit): Dump missed
>> optimization for loop niter analysis.
>>
>> gcc/testsuite/ChangeLog
>> 2017-07-13 Bin Cheng <bin.ch...@arm.com>
>>
>> PR target/81408
>> * g++.dg/tree-ssa/pr81408.C: New.
>> * gcc.dg/tree-ssa/pr19210-1.c: Check dump message rather than
>> warning.
diff --git a/gcc/testsuite/g++.dg/tree-ssa/pr81408.C
b/gcc/testsuite/g++.dg/tree-ssa/pr81408.C
new file mode 100644
index 0000000..f94544b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/tree-ssa/pr81408.C
@@ -0,0 +1,92 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -std=gnu++11 -fopt-info-loop-missed
-Wunsafe-loop-optimizations" } */
+
+namespace a {
+void b () __attribute__ ((__noreturn__));
+template <typename> struct d;
+template <typename e> struct d<e *>
+{
+ typedef e f;
+};
+struct g
+{
+ template <typename h> using i = h *;
+};
+}
+using a::d;
+template <typename j, typename> class k
+{
+ j l;
+
+public:
+ typename d<j>::f operator* () {}
+ void operator++ () { ++l; }
+ j
+ aa ()
+ {
+ return l;
+ }
+};
+template <typename m, typename n, typename ab>
+bool
+operator!= (k<m, ab> o, k<n, ab> p2)
+{
+ return o.aa () != p2.aa ();
+}
+struct p;
+namespace a {
+struct F
+{
+ struct q
+ {
+ using ai = g::i<p>;
+ };
+ using r = q::ai;
+};
+class H
+{
+public:
+ k<F::r, int> begin ();
+ k<F::r, int> end ();
+};
+int s;
+class I
+{
+public:
+ void
+ aq (char)
+ {
+ if (s)
+ b ();
+ }
+};
+class u : public I
+{
+public:
+ void
+ operator<< (u o (u))
+ {
+ o (*this);
+ }
+ u operator<< (void *);
+};
+template <typename at, typename au>
+at
+av (au o)
+{
+ o.aq ('\n');
+}
+u ax;
+}
+struct p
+{
+ char *ay;
+};
+a::H t;
+void
+ShowHelpListCommands ()
+{
+ for (auto c : t) /* { dg-message "note: missed loop optimization: niters
analysis .*" } */
+ a::ax << c.ay << a::av;
+}
+
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr19210-1.c
b/gcc/testsuite/gcc.dg/tree-ssa/pr19210-1.c
index 3c8ee06..0fa5600 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/pr19210-1.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr19210-1.c
@@ -1,15 +1,15 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -Wunsafe-loop-optimizations" } */
+/* { dg-options "-O2 -fopt-info-loop-missed -Wunsafe-loop-optimizations" } */
extern void g(void);
void
f (unsigned n)
{
unsigned k;
- for(k = 0;k <= n;k++) /* { dg-warning "missed loop optimization.*overflow" }
*/
+ for(k = 0;k <= n;k++) /* { dg-message "note: missed loop optimization:
niters analysis .*" } */
g();
- for(k = 0;k <= n;k += 4) /* { dg-warning "missed loop
optimization.*overflow" } */
+ for(k = 0;k <= n;k += 4) /* { dg-message "note: missed loop optimization:
niters analysis .*" } */
g();
/* We used to get warning for this loop. However, since then # of iterations
@@ -21,9 +21,9 @@ f (unsigned n)
g();
/* So we need the following loop, instead. */
- for(k = 4;k <= n;k += 5) /* { dg-warning "missed loop
optimization.*overflow" } */
+ for(k = 4;k <= n;k += 5) /* { dg-message "note: missed loop optimization:
niters analysis .*" } */
g();
- for(k = 15;k >= n;k--) /* { dg-warning "missed loop optimization.*overflow"
} */
+ for(k = 15;k >= n;k--) /* { dg-message "note: missed loop optimization:
niters analysis .*" } */
g();
}
diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c
index 5a7cab5..1421002 100644
--- a/gcc/tree-ssa-loop-niter.c
+++ b/gcc/tree-ssa-loop-niter.c
@@ -2378,9 +2378,9 @@ number_of_iterations_exit (struct loop *loop, edge exit,
return true;
if (warn)
- warning_at (gimple_location_safe (stmt),
- OPT_Wunsafe_loop_optimizations,
- "missed loop optimization, the loop counter may overflow");
+ dump_printf_loc (MSG_MISSED_OPTIMIZATION, gimple_location_safe (stmt),
+ "missed loop optimization: niters analysis ends up "
+ "with assumptions.\n");
return false;
}
