@@ -13433,6 +13433,10 @@ of iterations of a loop known, it adds a bonus of
@option{ipa-cp-loop-hint-bonus} to the profitability score of
the candidate.
+@item ipa-max-loop-predicates
+The maximum number of different predicates IPA will use to describe when
+loops in a function have known properties.
+
@item ipa-max-aa-steps
During its analysis of function bodies, IPA-CP employs alias analysis
in order to track values pointed to by function parameters. In order
@@ -3205,6 +3205,15 @@ hint_time_bonus (cgraph_node *node, const ipa_call_estimates &estimates)
ipa_hints hints = estimates.hints;
if (hints & (INLINE_HINT_loop_iterations | INLINE_HINT_loop_stride))
result += opt_for_fn (node->decl, param_ipa_cp_loop_hint_bonus);
+
+ sreal bonus_for_one = opt_for_fn (node->decl, param_ipa_cp_loop_hint_bonus);
+
+ if (hints & INLINE_HINT_loop_iterations)
+ result += (estimates.loops_with_known_iterations * bonus_for_one).to_int ();
+
+ if (hints & INLINE_HINT_loop_stride)
+ result += (estimates.loops_with_known_strides * bonus_for_one).to_int ();
+
return result;
}
@@ -310,6 +310,36 @@ set_hint_predicate (predicate **p, predicate new_predicate)
}
}
+/* Find if NEW_PREDICATE is already in V and if so, increment its freq.
+ Otherwise add a new item to the vector with this predicate and frerq equal
+ to add_freq, unless the number of predicates would exceed MAX_NUM_PREDICATES
+ in which case the function does nothing. */
+
+static void
+add_freqcounting_predicate (vec<ipa_freqcounting_predicate, va_gc> **v,
+ const predicate &new_predicate, sreal add_freq,
+ unsigned max_num_predicates)
+{
+ if (new_predicate == false || new_predicate == true)
+ return;
+ ipa_freqcounting_predicate *f;
+ for (int i = 0; vec_safe_iterate (*v, i, &f); i++)
+ if (new_predicate == f->predicate)
+ {
+ f->freq += add_freq;
+ return;
+ }
+ if (vec_safe_length (*v) >= max_num_predicates)
+ /* Too many different predicates to account for. */
+ return;
+
+ ipa_freqcounting_predicate fcp;
+ fcp.predicate = NULL;
+ set_hint_predicate (&fcp.predicate, new_predicate);
+ fcp.freq = add_freq;
+ vec_safe_push (*v, fcp);
+ return;
+}
/* Compute what conditions may or may not hold given information about
parameters. RET_CLAUSE returns truths that may hold in a specialized copy,
@@ -710,13 +740,17 @@ ipa_call_summary::~ipa_call_summary ()
ipa_fn_summary::~ipa_fn_summary ()
{
- if (loop_iterations)
- edge_predicate_pool.remove (loop_iterations);
- if (loop_stride)
- edge_predicate_pool.remove (loop_stride);
+ unsigned len = vec_safe_length (loop_iterations);
+ for (unsigned i = 0; i < len; i++)
+ edge_predicate_pool.remove ((*loop_iterations)[i].predicate);
+ len = vec_safe_length (loop_strides);
+ for (unsigned i = 0; i < len; i++)
+ edge_predicate_pool.remove ((*loop_strides)[i].predicate);
vec_free (conds);
vec_free (size_time_table);
vec_free (call_size_time_table);
+ vec_free (loop_iterations);
+ vec_free (loop_strides);
}
void
@@ -729,24 +763,33 @@ ipa_fn_summary_t::remove_callees (cgraph_node *node)
ipa_call_summaries->remove (e);
}
-/* Same as remap_predicate_after_duplication but handle hint predicate *P.
- Additionally care about allocating new memory slot for updated predicate
- and set it to NULL when it becomes true or false (and thus uninteresting).
- */
+/* Duplicate predicates in loop hint vector, allocating memory for them and
+ remove and deallocate any uninteresting (true or false) ones. Return the
+ result. */
-static void
-remap_hint_predicate_after_duplication (predicate **p,
- clause_t possible_truths)
+static vec<ipa_freqcounting_predicate, va_gc> *
+remap_freqcounting_preds_after_dup (vec<ipa_freqcounting_predicate, va_gc> *v,
+ clause_t possible_truths)
{
- predicate new_predicate;
+ if (vec_safe_length (v) == 0)
+ return NULL;
- if (!*p)
- return;
+ vec<ipa_freqcounting_predicate, va_gc> *res = v->copy ();
+ int len = res->length();
+ for (int i = len - 1; i >= 0; i--)
+ {
+ predicate new_predicate
+ = (*res)[i].predicate->remap_after_duplication (possible_truths);
+ /* We do not want to free previous predicate; it is used by node
+ origin. */
+ (*res)[i].predicate = NULL;
+ set_hint_predicate (&(*res)[i].predicate, new_predicate);
- new_predicate = (*p)->remap_after_duplication (possible_truths);
- /* We do not want to free previous predicate; it is used by node origin. */
- *p = NULL;
- set_hint_predicate (p, new_predicate);
+ if (!(*res)[i].predicate)
+ res->unordered_remove (i);
+ }
+
+ return res;
}
@@ -859,9 +902,11 @@ ipa_fn_summary_t::duplicate (cgraph_node *src,
optimized_out_size += es->call_stmt_size * ipa_fn_summary::size_scale;
edge_set_predicate (edge, &new_predicate);
}
- remap_hint_predicate_after_duplication (&info->loop_iterations,
+ info->loop_iterations
+ = remap_freqcounting_preds_after_dup (info->loop_iterations,
possible_truths);
- remap_hint_predicate_after_duplication (&info->loop_stride,
+ info->loop_strides
+ = remap_freqcounting_preds_after_dup (info->loop_strides,
possible_truths);
/* If inliner or someone after inliner will ever start producing
@@ -873,17 +918,21 @@ ipa_fn_summary_t::duplicate (cgraph_node *src,
else
{
info->size_time_table = vec_safe_copy (info->size_time_table);
- if (info->loop_iterations)
+ info->loop_iterations = vec_safe_copy (info->loop_iterations);
+ info->loop_strides = vec_safe_copy (info->loop_strides);
+
+ ipa_freqcounting_predicate *f;
+ for (int i = 0; vec_safe_iterate (info->loop_iterations, i, &f); i++)
{
- predicate p = *info->loop_iterations;
- info->loop_iterations = NULL;
- set_hint_predicate (&info->loop_iterations, p);
+ predicate p = *f->predicate;
+ f->predicate = NULL;
+ set_hint_predicate (&f->predicate, p);
}
- if (info->loop_stride)
+ for (int i = 0; vec_safe_iterate (info->loop_strides, i, &f); i++)
{
- predicate p = *info->loop_stride;
- info->loop_stride = NULL;
- set_hint_predicate (&info->loop_stride, p);
+ predicate p = *f->predicate;
+ f->predicate = NULL;
+ set_hint_predicate (&f->predicate, p);
}
}
if (!dst->inlined_to)
@@ -1045,15 +1094,28 @@ ipa_dump_fn_summary (FILE *f, struct cgraph_node *node)
}
fprintf (f, "\n");
}
- if (s->loop_iterations)
+ ipa_freqcounting_predicate *fcp;
+ bool first_fcp = true;
+ for (int i = 0; vec_safe_iterate (s->loop_iterations, i, &fcp); i++)
{
- fprintf (f, " loop iterations:");
- s->loop_iterations->dump (f, s->conds);
+ if (first_fcp)
+ {
+ fprintf (f, " loop iterations:");
+ first_fcp = false;
+ }
+ fprintf (f, " %3.2f for ", fcp->freq.to_double ());
+ fcp->predicate->dump (f, s->conds);
}
- if (s->loop_stride)
+ first_fcp = true;
+ for (int i = 0; vec_safe_iterate (s->loop_strides, i, &fcp); i++)
{
- fprintf (f, " loop stride:");
- s->loop_stride->dump (f, s->conds);
+ if (first_fcp)
+ {
+ fprintf (f, " loop strides:");
+ first_fcp = false;
+ }
+ fprintf (f, " %3.2f for :", fcp->freq.to_double ());
+ fcp->predicate->dump (f, s->conds);
}
fprintf (f, " calls:\n");
dump_ipa_call_summary (f, 4, node, s);
@@ -2543,12 +2605,13 @@ analyze_function_body (struct cgraph_node *node, bool early)
if (fbi.info)
compute_bb_predicates (&fbi, node, info, params_summary);
+ const profile_count entry_count = ENTRY_BLOCK_PTR_FOR_FN (cfun)->count;
order = XNEWVEC (int, n_basic_blocks_for_fn (cfun));
nblocks = pre_and_rev_post_order_compute (NULL, order, false);
for (n = 0; n < nblocks; n++)
{
bb = BASIC_BLOCK_FOR_FN (cfun, order[n]);
- freq = bb->count.to_sreal_scale (ENTRY_BLOCK_PTR_FOR_FN (cfun)->count);
+ freq = bb->count.to_sreal_scale (entry_count);
if (clobber_only_eh_bb_p (bb))
{
if (dump_file && (dump_flags & TDF_DETAILS))
@@ -2790,23 +2853,28 @@ analyze_function_body (struct cgraph_node *node, bool early)
if (nonconstant_names.exists () && !early)
{
+ ipa_fn_summary *s = ipa_fn_summaries->get (node);
class loop *loop;
- predicate loop_iterations = true;
- predicate loop_stride = true;
+ unsigned max_loop_predicates = opt_for_fn (node->decl,
+ param_ipa_max_loop_predicates);
if (dump_file && (dump_flags & TDF_DETAILS))
flow_loops_dump (dump_file, NULL, 0);
scev_initialize ();
FOR_EACH_LOOP (loop, 0)
{
+ predicate loop_iterations = true;
+ sreal header_freq;
edge ex;
unsigned int j;
class tree_niter_desc niter_desc;
- if (loop->header->aux)
- bb_predicate = *(predicate *) loop->header->aux;
- else
- bb_predicate = false;
+ if (!loop->header->aux)
+ continue;
+ profile_count phdr_count = loop_preheader_edge (loop)->count ();
+ sreal phdr_freq = phdr_count.to_sreal_scale (entry_count);
+
+ bb_predicate = *(predicate *) loop->header->aux;
auto_vec<edge> exits = get_loop_exit_edges (loop);
FOR_EACH_VEC_ELT (exits, j, ex)
if (number_of_iterations_exit (loop, ex, &niter_desc, false)
@@ -2821,10 +2889,10 @@ analyze_function_body (struct cgraph_node *node, bool early)
will_be_nonconstant = bb_predicate & will_be_nonconstant;
if (will_be_nonconstant != true
&& will_be_nonconstant != false)
- /* This is slightly inprecise. We may want to represent each
- loop with independent predicate. */
loop_iterations &= will_be_nonconstant;
}
+ add_freqcounting_predicate (&s->loop_iterations, loop_iterations,
+ phdr_freq, max_loop_predicates);
}
/* To avoid quadratic behavior we analyze stride predicates only
@@ -2833,14 +2901,17 @@ analyze_function_body (struct cgraph_node *node, bool early)
for (loop = loops_for_fn (cfun)->tree_root->inner;
loop != NULL; loop = loop->next)
{
+ predicate loop_stride = true;
basic_block *body = get_loop_body (loop);
+ profile_count phdr_count = loop_preheader_edge (loop)->count ();
+ sreal phdr_freq = phdr_count.to_sreal_scale (entry_count);
for (unsigned i = 0; i < loop->num_nodes; i++)
{
gimple_stmt_iterator gsi;
- if (body[i]->aux)
- bb_predicate = *(predicate *) body[i]->aux;
- else
- bb_predicate = false;
+ if (!body[i]->aux)
+ continue;
+
+ bb_predicate = *(predicate *) body[i]->aux;
for (gsi = gsi_start_bb (body[i]); !gsi_end_p (gsi);
gsi_next (&gsi))
{
@@ -2869,16 +2940,13 @@ analyze_function_body (struct cgraph_node *node, bool early)
will_be_nonconstant = bb_predicate & will_be_nonconstant;
if (will_be_nonconstant != true
&& will_be_nonconstant != false)
- /* This is slightly inprecise. We may want to represent
- each loop with independent predicate. */
loop_stride = loop_stride & will_be_nonconstant;
}
}
+ add_freqcounting_predicate (&s->loop_strides, loop_stride,
+ phdr_freq, max_loop_predicates);
free (body);
}
- ipa_fn_summary *s = ipa_fn_summaries->get (node);
- set_hint_predicate (&s->loop_iterations, loop_iterations);
- set_hint_predicate (&s->loop_stride, loop_stride);
scev_finalize ();
}
FOR_ALL_BB_FN (bb, my_function)
@@ -3551,6 +3619,8 @@ ipa_call_context::estimate_size_and_time (ipa_call_estimates *estimates,
sreal time = 0;
int min_size = 0;
ipa_hints hints = 0;
+ sreal loops_with_known_iterations = 0;
+ sreal loops_with_known_strides = 0;
int i;
if (dump_file && (dump_flags & TDF_DETAILS))
@@ -3643,16 +3713,27 @@ ipa_call_context::estimate_size_and_time (ipa_call_estimates *estimates,
if (est_hints)
{
- if (info->loop_iterations
- && !info->loop_iterations->evaluate (m_possible_truths))
- hints |= INLINE_HINT_loop_iterations;
- if (info->loop_stride
- && !info->loop_stride->evaluate (m_possible_truths))
- hints |= INLINE_HINT_loop_stride;
if (info->scc_no)
hints |= INLINE_HINT_in_scc;
if (DECL_DECLARED_INLINE_P (m_node->decl))
hints |= INLINE_HINT_declared_inline;
+
+ ipa_freqcounting_predicate *fcp;
+ for (i = 0; vec_safe_iterate (info->loop_iterations, i, &fcp); i++)
+ if (!fcp->predicate->evaluate (m_possible_truths))
+ {
+ hints |= INLINE_HINT_loop_iterations;
+ loops_with_known_iterations += fcp->freq;
+ }
+ estimates->loops_with_known_iterations = loops_with_known_iterations;
+
+ for (i = 0; vec_safe_iterate (info->loop_strides, i, &fcp); i++)
+ if (!fcp->predicate->evaluate (m_possible_truths))
+ {
+ hints |= INLINE_HINT_loop_stride;
+ loops_with_known_strides += fcp->freq;
+ }
+ estimates->loops_with_known_strides = loops_with_known_strides;
}
size = RDIV (size, ipa_fn_summary::size_scale);
@@ -3660,12 +3741,15 @@ ipa_call_context::estimate_size_and_time (ipa_call_estimates *estimates,
if (dump_file && (dump_flags & TDF_DETAILS))
{
+ fprintf (dump_file, "\n size:%i", (int) size);
if (est_times)
- fprintf (dump_file, "\n size:%i time:%f nonspec time:%f\n",
- (int) size, time.to_double (),
- nonspecialized_time.to_double ());
- else
- fprintf (dump_file, "\n size:%i (time not estimated)\n", (int) size);
+ fprintf (dump_file, " time:%f nonspec time:%f",
+ time.to_double (), nonspecialized_time.to_double ());
+ if (est_hints)
+ fprintf (dump_file, " loops with known iterations:%f "
+ "known strides:%f", loops_with_known_iterations.to_double (),
+ loops_with_known_strides.to_double ());
+ fprintf (dump_file, "\n");
}
if (est_times)
{
@@ -3865,32 +3949,29 @@ remap_edge_summaries (struct cgraph_edge *inlined_edge,
}
}
-/* Same as remap_predicate, but set result into hint *HINT. */
+/* Run remap_after_inlining on each predicate in V. */
static void
-remap_hint_predicate (class ipa_fn_summary *info,
- class ipa_node_params *params_summary,
- class ipa_fn_summary *callee_info,
- predicate **hint,
- vec<int> operand_map,
- vec<int> offset_map,
- clause_t possible_truths,
- predicate *toplev_predicate)
-{
- predicate p;
+remap_freqcounting_predicate (class ipa_fn_summary *info,
+ class ipa_node_params *params_summary,
+ class ipa_fn_summary *callee_info,
+ vec<ipa_freqcounting_predicate, va_gc> *v,
+ vec<int> operand_map,
+ vec<int> offset_map,
+ clause_t possible_truths,
+ predicate *toplev_predicate)
- if (!*hint)
- return;
- p = (*hint)->remap_after_inlining
- (info, params_summary, callee_info,
- operand_map, offset_map,
- possible_truths, *toplev_predicate);
- if (p != false && p != true)
+{
+ ipa_freqcounting_predicate *fcp;
+ for (int i = 0; vec_safe_iterate (v, i, &fcp); i++)
{
- if (!*hint)
- set_hint_predicate (hint, p);
- else
- **hint &= p;
+ predicate p
+ = fcp->predicate->remap_after_inlining (info, params_summary,
+ callee_info, operand_map,
+ offset_map, possible_truths,
+ *toplev_predicate);
+ if (p != false && p != true)
+ *fcp->predicate &= p;
}
}
@@ -3998,12 +4079,12 @@ ipa_merge_fn_summary_after_inlining (struct cgraph_edge *edge)
remap_edge_summaries (edge, edge->callee, info, params_summary,
callee_info, operand_map,
offset_map, clause, &toplev_predicate);
- remap_hint_predicate (info, params_summary, callee_info,
- &callee_info->loop_iterations,
- operand_map, offset_map, clause, &toplev_predicate);
- remap_hint_predicate (info, params_summary, callee_info,
- &callee_info->loop_stride,
- operand_map, offset_map, clause, &toplev_predicate);
+ remap_freqcounting_predicate (info, params_summary, callee_info,
+ info->loop_iterations, operand_map,
+ offset_map, clause, &toplev_predicate);
+ remap_freqcounting_predicate (info, params_summary, callee_info,
+ info->loop_strides, operand_map,
+ offset_map, clause, &toplev_predicate);
HOST_WIDE_INT stack_frame_offset = ipa_get_stack_frame_offset (edge->callee);
HOST_WIDE_INT peak = stack_frame_offset + callee_info->estimated_stack_size;
@@ -4334,12 +4415,34 @@ inline_read_section (struct lto_file_decl_data *file_data, const char *data,
info->size_time_table->quick_push (e);
}
- p.stream_in (&ib);
- if (info)
- set_hint_predicate (&info->loop_iterations, p);
- p.stream_in (&ib);
- if (info)
- set_hint_predicate (&info->loop_stride, p);
+ count2 = streamer_read_uhwi (&ib);
+ for (j = 0; j < count2; j++)
+ {
+ p.stream_in (&ib);
+ sreal fcp_freq = sreal::stream_in (&ib);
+ if (info)
+ {
+ ipa_freqcounting_predicate fcp;
+ fcp.predicate = NULL;
+ set_hint_predicate (&fcp.predicate, p);
+ fcp.freq = fcp_freq;
+ vec_safe_push (info->loop_iterations, fcp);
+ }
+ }
+ count2 = streamer_read_uhwi (&ib);
+ for (j = 0; j < count2; j++)
+ {
+ p.stream_in (&ib);
+ sreal fcp_freq = sreal::stream_in (&ib);
+ if (info)
+ {
+ ipa_freqcounting_predicate fcp;
+ fcp.predicate = NULL;
+ set_hint_predicate (&fcp.predicate, p);
+ fcp.freq = fcp_freq;
+ vec_safe_push (info->loop_strides, fcp);
+ }
+ }
for (e = node->callees; e; e = e->next_callee)
read_ipa_call_summary (&ib, e, info != NULL);
for (e = node->indirect_calls; e; e = e->next_callee)
@@ -4502,14 +4605,19 @@ ipa_fn_summary_write (void)
e->exec_predicate.stream_out (ob);
e->nonconst_predicate.stream_out (ob);
}
- if (info->loop_iterations)
- info->loop_iterations->stream_out (ob);
- else
- streamer_write_uhwi (ob, 0);
- if (info->loop_stride)
- info->loop_stride->stream_out (ob);
- else
- streamer_write_uhwi (ob, 0);
+ ipa_freqcounting_predicate *fcp;
+ streamer_write_uhwi (ob, vec_safe_length (info->loop_iterations));
+ for (i = 0; vec_safe_iterate (info->loop_iterations, i, &fcp); i++)
+ {
+ fcp->predicate->stream_out (ob);
+ fcp->freq.stream_out (ob);
+ }
+ streamer_write_uhwi (ob, vec_safe_length (info->loop_strides));
+ for (i = 0; vec_safe_iterate (info->loop_strides, i, &fcp); i++)
+ {
+ fcp->predicate->stream_out (ob);
+ fcp->freq.stream_out (ob);
+ }
for (edge = cnode->callees; edge; edge = edge->next_callee)
write_ipa_call_summary (ob, edge);
for (edge = cnode->indirect_calls; edge; edge = edge->next_callee)
@@ -101,6 +101,19 @@ public:
}
};
+/* Structure to capture how frequently some interesting events occur given a
+ particular predicate. The structure is used to estimate how often we
+ encounter loops with known iteration count or stride in various
+ contexts. */
+
+struct GTY(()) ipa_freqcounting_predicate
+{
+ /* The described event happens with this frequency... */
+ sreal freq;
+ /* ...when this predicate evaluates to false. */
+ class predicate * GTY((skip)) predicate;
+};
+
/* Function inlining information. */
class GTY(()) ipa_fn_summary
{
@@ -112,8 +125,9 @@ public:
inlinable (false), single_caller (false),
fp_expressions (false), estimated_stack_size (false),
time (0), conds (NULL),
- size_time_table (NULL), call_size_time_table (NULL), loop_iterations (NULL),
- loop_stride (NULL), growth (0), scc_no (0)
+ size_time_table (NULL), call_size_time_table (NULL),
+ loop_iterations (NULL), loop_strides (NULL),
+ growth (0), scc_no (0)
{
}
@@ -125,7 +139,7 @@ public:
estimated_stack_size (s.estimated_stack_size),
time (s.time), conds (s.conds), size_time_table (s.size_time_table),
call_size_time_table (NULL),
- loop_iterations (s.loop_iterations), loop_stride (s.loop_stride),
+ loop_iterations (s.loop_iterations), loop_strides (s.loop_strides),
growth (s.growth), scc_no (s.scc_no)
{}
@@ -164,12 +178,10 @@ public:
vec<size_time_entry, va_gc> *size_time_table;
vec<size_time_entry, va_gc> *call_size_time_table;
- /* Predicate on when some loop in the function becomes to have known
- bounds. */
- predicate * GTY((skip)) loop_iterations;
- /* Predicate on when some loop in the function becomes to have known
- stride. */
- predicate * GTY((skip)) loop_stride;
+ /* Predicates on when some loops in the function can have known bounds. */
+ vec<ipa_freqcounting_predicate, va_gc> *loop_iterations;
+ /* Predicates on when some loops in the function can have known strides. */
+ vec<ipa_freqcounting_predicate, va_gc> *loop_strides;
/* Estimated growth for inlining all copies of the function before start
of small functions inlining.
This value will get out of date as the callers are duplicated, but
@@ -308,6 +320,14 @@ struct ipa_call_estimates
/* Further discovered reasons why to inline or specialize the give calls. */
ipa_hints hints;
+
+ /* Frequency how often a loop with known number of iterations is encountered.
+ Calculated with hints. */
+ sreal loops_with_known_iterations;
+
+ /* Frequency how often a loop with known strides is encountered. Calculated
+ with hints. */
+ sreal loops_with_known_strides;
};
class ipa_cached_call_context;
@@ -234,6 +234,10 @@ Maximum number of aggregate content items for a parameter in jump functions and
Common Joined UInteger Var(param_ipa_max_param_expr_ops) Init(10) Param Optimization
Maximum number of operations in a parameter expression that can be handled by IPA analysis.
+-param=ipa-max-loop-predicates=
+Common Joined UInteger Var(param_ipa_max_loop_predicates) Init(16) Param Optimization
+Maximum number of different predicates used to track properties of loops in IPA analysis.
+
-param=ipa-max-switch-predicate-bounds=
Common Joined UInteger Var(param_ipa_max_switch_predicate_bounds) Init(5) Param Optimization
Maximal number of boundary endpoints of case ranges of switch statement used during IPA function summary generation.
new file mode 100644
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -fdump-ipa-cp-details" } */
+
+extern int *o, *p, *q, *r;
+
+#define FUNCTIONS fa(), fb(), fc(), fd(), fe(), ff(), fg()
+
+extern void FUNCTIONS;
+
+void foo (int c)
+{
+ FUNCTIONS;
+ FUNCTIONS;
+ for (int i = 0; i < 100; i++)
+ {
+ for (int j = 0; j < c; j++)
+ o[i] = p[i] + q[i] * r[i];
+ }
+ FUNCTIONS;
+ FUNCTIONS;
+}
+
+void bar()
+{
+ foo (8);
+ p[4]++;
+}
+
+/* { dg-final { scan-ipa-dump {with known iterations:[1-9]} "cp" } } */