In do_warn_aggressive_loop_optimizations, we convert to a tree just to print a
widest_int. Apart from overly complicated, this results in printing '3u'
instead of just '3'.
Unfortunately, adding a printf-like conversion specifier would require making
pretty-print.c link with wide-int.cc, which will include a lot of new
dependencies into several other programs (gcov-tool for example). It would be
possible to add the conversion specifier to every FE pretty-printer, but this
still would require updating c-format.c, which is far from trivial. A simpler
approach is to convert to a string rather than to a tree.
In addition, "iteration 3 invokes undefined behavior within this loop"
seems to me clearer than "iteration 3 invokes undefined behavior;
containing loop".
Boot&tested in x86_64-linux-gnu
OK?
gcc/testsuite/ChangeLog:
2015-09-20 Manuel López-Ibáñez <m...@gcc.gnu.org>
PR middle-end/60832
* gcc.dg/pr53265.c: Update.
gcc/ChangeLog:
2015-09-20 Manuel López-Ibáñez <m...@gcc.gnu.org>
PR middle-end/60832
* tree-ssa-loop-niter.c (do_warn_aggressive_loop_optimizations):
Print i_bound without converting it to a tree.
Index: gcc/tree-ssa-loop-niter.c
===================================================================
--- gcc/tree-ssa-loop-niter.c (revision 227878)
+++ gcc/tree-ssa-loop-niter.c (working copy)
@@ -2909,15 +2909,16 @@ do_warn_aggressive_loop_optimizations (s
edge e = single_exit (loop);
if (e == NULL)
return;
gimple estmt = last_stmt (e->src);
+ char buf[WIDE_INT_PRINT_BUFFER_SIZE];
+ print_dec (i_bound, buf, TYPE_UNSIGNED (TREE_TYPE (loop->nb_iterations))
+ ? UNSIGNED : SIGNED);
if (warning_at (gimple_location (stmt), OPT_Waggressive_loop_optimizations,
- "iteration %E invokes undefined behavior",
- wide_int_to_tree (TREE_TYPE (loop->nb_iterations),
- i_bound)))
- inform (gimple_location (estmt), "containing loop");
+ "iteration %s invokes undefined behavior", buf))
+ inform (gimple_location (estmt), "within this loop");
loop->warned_aggressive_loop_optimizations = true;
}
/* Records that AT_STMT is executed at most BOUND + 1 times in LOOP. IS_EXIT
is true if the loop is exited immediately after STMT, and this exit
Index: gcc/testsuite/gcc.dg/pr53265.c
===================================================================
--- gcc/testsuite/gcc.dg/pr53265.c (revision 227878)
+++ gcc/testsuite/gcc.dg/pr53265.c (working copy)
@@ -10,36 +10,36 @@ void
fn1 (void)
{
unsigned int a[128];
int i;
- for (i = 0; i < 128; ++i) /* { dg-message "note: containing loop" } */
- a[i] = i * 0x02000001; /* { dg-warning "invokes undefined behavior" }
*/
+ for (i = 0; i < 128; ++i) /* { dg-message "note: within this loop" } */
+ a[i] = i * 0x02000001; /* { dg-warning "64 invokes undefined behavior"
} */
bar (a);
}
void
fn2 (void)
{
unsigned long long a[128];
int i;
- for (i = 0; i < 128; i++) /* { dg-message "note:
containing loop" } */
- a[i] = (i + 1LL) * 0x0123456789ABCDEFLL; /* { dg-warning "invokes
undefined behavior" } */
+ for (i = 0; i < 128; i++) /* { dg-message "note: within
this loop" } */
+ a[i] = (i + 1LL) * 0x0123456789ABCDEFLL; /* { dg-warning "112 invokes
undefined behavior" } */
bar (a);
}
void
fn3 (void)
{
unsigned char a[16], b[16], c[16];
int i;
bar (b);
- for (i = 0; i < (int) (sizeof (a) / sizeof (a[0])); i++) /* { dg-message
"note: containing loop" } */
+ for (i = 0; i < (int) (sizeof (a) / sizeof (a[0])); i++) /* { dg-message
"note: within this loop" } */
{
- c[i + 8] = b[i]; /* { dg-warning "invokes undefined behavior" } */
+ c[i + 8] = b[i]; /* { dg-warning "8 invokes undefined behavior" } */
a[i + 8] = b[i + 8];
}
bar (a);
bar (c);
}
@@ -48,13 +48,13 @@ void
fn4 (void)
{
unsigned int *a[32], *o, i;
bar (a);
- for (i = 0; i <= sizeof (a) / sizeof (a[0]); i++) /* { dg-message "note:
containing loop" "" } */
+ for (i = 0; i <= sizeof (a) / sizeof (a[0]); i++) /* { dg-message "note:
within this loop" "" } */
{
- o = a[i]; /* { dg-warning "invokes undefined behavior" "" } */
+ o = a[i]; /* { dg-warning "32 invokes undefined behavior" "" } */
bar (o);
}
}
void
@@ -63,36 +63,36 @@ fn5 (void)
unsigned short a[23940];
unsigned int b[1140];
int j;
bar (b);
- for (j = 0; j < 1140; j++) /* { dg-message "note: containing loop" } */
- a[23940 + j - 950] = b[j]; /* { dg-warning "invokes undefined behavior" }
*/
+ for (j = 0; j < 1140; j++) /* { dg-message "note: within this loop" } */
+ a[23940 + j - 950] = b[j]; /* { dg-warning "950 invokes undefined
behavior" } */
bar (a);
}
void
fn6 (void)
{
double a[4][3], b[12];
int i;
bar (b);
- for (i = 0; i < 12; i++) /* { dg-message "note: containing loop" } */
- a[0][i] = b[i] / 10000.0; /* { dg-warning "invokes undefined behavior" }
*/
+ for (i = 0; i < 12; i++) /* { dg-message "note: within this loop" } */
+ a[0][i] = b[i] / 10000.0; /* { dg-warning "3 invokes undefined behavior"
} */
bar (a);
}
void
fn7 (void)
{
int a[16], b, c;
bar (a);
- for (b = a[c = 0]; c < 16; b = a[++c]) /* { dg-warning "invokes
undefined behavior" "" } */
+ for (b = a[c = 0]; c < 16; b = a[++c]) /* { dg-warning "15 invokes
undefined behavior" "" } */
baz (b);
}
-/* { dg-message "note: containing loop" "" { target *-*-* } 89 } */
+/* { dg-message "note: within this loop" "" { target *-*-* } 89 } */
const void *va, *vb, *vc, *vd, *ve;
const void *vf[4];
void
fn8 (void)
@@ -132,12 +132,12 @@ int xa[18];
void
fn10 (void)
{
int i;
- for (i = 16; i < 32; i++) /* { dg-message "note: containing loop" } */
- xa[i] = 26; /* { dg-warning "invokes undefined
behavior" } */
+ for (i = 16; i < 32; i++) /* { dg-message "note: within this loop" } */
+ xa[i] = 26; /* { dg-warning "2 invokes undefined
behavior" } */
}
__attribute__((noinline)) static void
fn11 (int x)
{
