/* Natural loop discovery code for GNU compiler.
- Copyright (C) 2000-2015 Free Software Foundation, Inc.
+ Copyright (C) 2000-2019 Free Software Foundation, Inc.
This file is part of GCC.
#include "system.h"
#include "coretypes.h"
#include "backend.h"
-#include "cfghooks.h"
+#include "rtl.h"
#include "tree.h"
#include "gimple.h"
-#include "rtl.h"
+#include "cfghooks.h"
+#include "gimple-ssa.h"
+#include "diagnostic-core.h"
#include "cfganal.h"
#include "cfgloop.h"
-#include "diagnostic-core.h"
-#include "flags.h"
-#include "fold-const.h"
-#include "internal-fn.h"
#include "gimple-iterator.h"
-#include "gimple-ssa.h"
#include "dumpfile.h"
static void flow_loops_cfg_dump (FILE *);
loop_depth (loop), (long) (loop_outer (loop)
? loop_outer (loop)->num : -1));
+ if (loop->latch)
+ {
+ bool read_profile_p;
+ gcov_type nit = expected_loop_iterations_unbounded (loop, &read_profile_p);
+ if (read_profile_p && !loop->any_estimate)
+ fprintf (file, ";; profile-based iteration count: %" PRIu64 "\n",
+ (uint64_t) nit);
+ }
+
fprintf (file, ";; nodes:");
bbs = get_loop_body (loop);
for (i = 0; i < loop->num_nodes; i++)
/* Add LOOP to the loop hierarchy tree where FATHER is father of the
added loop. If LOOP has some children, take care of that their
- pred field will be initialized correctly. */
+ pred field will be initialized correctly. If AFTER is non-null
+ then it's expected it's a pointer into FATHERs inner sibling
+ list and LOOP is added behind AFTER, otherwise it's added in front
+ of FATHERs siblings. */
void
-flow_loop_tree_node_add (struct loop *father, struct loop *loop)
+flow_loop_tree_node_add (struct loop *father, struct loop *loop,
+ struct loop *after)
{
- loop->next = father->inner;
- father->inner = loop;
+ if (after)
+ {
+ loop->next = after->next;
+ after->next = loop;
+ }
+ else
+ {
+ loop->next = father->inner;
+ father->inner = loop;
+ }
establish_preds (loop, father);
}
loop->exits = ggc_cleared_alloc<loop_exit> ();
loop->exits->next = loop->exits->prev = loop->exits;
loop->can_be_parallel = false;
+ loop->constraints = 0;
loop->nb_iterations_upper_bound = 0;
+ loop->nb_iterations_likely_upper_bound = 0;
loop->nb_iterations_estimate = 0;
return loop;
}
return loops;
}
+/* qsort helper for sort_sibling_loops. */
+
+static int *sort_sibling_loops_cmp_rpo;
+static int
+sort_sibling_loops_cmp (const void *la_, const void *lb_)
+{
+ const struct loop *la = *(const struct loop * const *)la_;
+ const struct loop *lb = *(const struct loop * const *)lb_;
+ return (sort_sibling_loops_cmp_rpo[la->header->index]
+ - sort_sibling_loops_cmp_rpo[lb->header->index]);
+}
+
+/* Sort sibling loops in RPO order. */
+
+void
+sort_sibling_loops (function *fn)
+{
+ /* Match flow_loops_find in the order we sort sibling loops. */
+ sort_sibling_loops_cmp_rpo = XNEWVEC (int, last_basic_block_for_fn (cfun));
+ int *rc_order = XNEWVEC (int, n_basic_blocks_for_fn (cfun));
+ pre_and_rev_post_order_compute_fn (fn, NULL, rc_order, false);
+ for (int i = 0; i < n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS; ++i)
+ sort_sibling_loops_cmp_rpo[rc_order[i]] = i;
+ free (rc_order);
+
+ auto_vec<loop_p, 3> siblings;
+ loop_p loop;
+ FOR_EACH_LOOP_FN (fn, loop, LI_INCLUDE_ROOT)
+ if (loop->inner && loop->inner->next)
+ {
+ loop_p sibling = loop->inner;
+ do
+ {
+ siblings.safe_push (sibling);
+ sibling = sibling->next;
+ }
+ while (sibling);
+ siblings.qsort (sort_sibling_loops_cmp);
+ loop_p *siblingp = &loop->inner;
+ for (unsigned i = 0; i < siblings.length (); ++i)
+ {
+ *siblingp = siblings[i];
+ siblingp = &(*siblingp)->next;
+ }
+ *siblingp = NULL;
+ siblings.truncate (0);
+ }
+
+ free (sort_sibling_loops_cmp_rpo);
+ sort_sibling_loops_cmp_rpo = NULL;
+}
+
/* Ratio of frequencies of edges so that one of more latch edges is
considered to belong to inner loop with same header. */
#define HEAVY_EDGE_RATIO 8
{
unsigned i;
edge e, me = NULL;
- gcov_type mcount = 0, tcount = 0;
+ profile_count mcount = profile_count::zero (), tcount = profile_count::zero ();
FOR_EACH_VEC_ELT (latches, i, e)
{
- if (e->count > mcount)
+ if (e->count ()> mcount)
{
me = e;
- mcount = e->count;
+ mcount = e->count();
}
- tcount += e->count;
+ tcount += e->count();
}
- if (tcount < HEAVY_EDGE_MIN_SAMPLES
- || (tcount - mcount) * HEAVY_EDGE_RATIO > tcount)
+ if (!tcount.initialized_p () || !(tcount.ipa () > HEAVY_EDGE_MIN_SAMPLES)
+ || (tcount - mcount).apply_scale (HEAVY_EDGE_RATIO, 1) > tcount)
return NULL;
if (dump_file)
{
basic_block *blocks;
basic_block bb;
- bitmap visited;
- unsigned int i = 0;
- unsigned int vc = 1;
+ unsigned int i = 1;
+ unsigned int vc = 0;
gcc_assert (loop->num_nodes);
gcc_assert (loop->latch != EXIT_BLOCK_PTR_FOR_FN (cfun));
blocks = XNEWVEC (basic_block, loop->num_nodes);
- visited = BITMAP_ALLOC (NULL);
-
- bb = loop->header;
+ auto_bitmap visited;
+ blocks[0] = loop->header;
+ bitmap_set_bit (visited, loop->header->index);
while (i < loop->num_nodes)
{
edge e;
edge_iterator ei;
-
- if (bitmap_set_bit (visited, bb->index))
- /* This basic block is now visited */
- blocks[i++] = bb;
+ gcc_assert (i > vc);
+ bb = blocks[vc++];
FOR_EACH_EDGE (e, ei, bb->succs)
{
if (flow_bb_inside_loop_p (loop, e->dest))
{
+ /* This bb is now visited. */
if (bitmap_set_bit (visited, e->dest->index))
blocks[i++] = e->dest;
}
}
-
- gcc_assert (i > vc);
-
- bb = blocks[vc++];
}
- BITMAP_FREE (visited);
return blocks;
}
/* Releases lists of loop exits. */
void
-release_recorded_exits (void)
+release_recorded_exits (function *fn)
{
- gcc_assert (loops_state_satisfies_p (LOOPS_HAVE_RECORDED_EXITS));
- current_loops->exits->empty ();
- current_loops->exits = NULL;
- loops_state_clear (LOOPS_HAVE_RECORDED_EXITS);
+ gcc_assert (loops_state_satisfies_p (fn, LOOPS_HAVE_RECORDED_EXITS));
+ loops_for_fn (fn)->exits->empty ();
+ loops_for_fn (fn)->exits = NULL;
+ loops_state_clear (fn, LOOPS_HAVE_RECORDED_EXITS);
}
/* Returns the list of the exit edges of a LOOP. */
verify_loop_structure (void)
{
unsigned *sizes, i, j;
- sbitmap irreds;
basic_block bb, *bbs;
struct loop *loop;
int err = 0;
unsigned num = number_of_loops (cfun);
struct loop_exit *exit, *mexit;
bool dom_available = dom_info_available_p (CDI_DOMINATORS);
- sbitmap visited;
if (loops_state_satisfies_p (LOOPS_NEED_FIXUP))
{
}
/* Check the recorded loop father and sizes of loops. */
- visited = sbitmap_alloc (last_basic_block_for_fn (cfun));
+ auto_sbitmap visited (last_basic_block_for_fn (cfun));
bitmap_clear (visited);
bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun));
FOR_EACH_LOOP (loop, LI_FROM_INNERMOST)
}
}
free (bbs);
- sbitmap_free (visited);
/* Check headers and latches. */
FOR_EACH_LOOP (loop, 0)
/* Check irreducible loops. */
if (loops_state_satisfies_p (LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS))
{
+ auto_edge_flag saved_irr_mask (cfun);
/* Record old info. */
- irreds = sbitmap_alloc (last_basic_block_for_fn (cfun));
+ auto_sbitmap irreds (last_basic_block_for_fn (cfun));
FOR_EACH_BB_FN (bb, cfun)
{
edge_iterator ei;
bitmap_clear_bit (irreds, bb->index);
FOR_EACH_EDGE (e, ei, bb->succs)
if (e->flags & EDGE_IRREDUCIBLE_LOOP)
- e->flags |= EDGE_ALL_FLAGS + 1;
+ e->flags |= saved_irr_mask;
}
/* Recount it. */
FOR_EACH_EDGE (e, ei, bb->succs)
{
if ((e->flags & EDGE_IRREDUCIBLE_LOOP)
- && !(e->flags & (EDGE_ALL_FLAGS + 1)))
+ && !(e->flags & saved_irr_mask))
{
error ("edge from %d to %d should be marked irreducible",
e->src->index, e->dest->index);
err = 1;
}
else if (!(e->flags & EDGE_IRREDUCIBLE_LOOP)
- && (e->flags & (EDGE_ALL_FLAGS + 1)))
+ && (e->flags & saved_irr_mask))
{
error ("edge from %d to %d should not be marked irreducible",
e->src->index, e->dest->index);
err = 1;
}
- e->flags &= ~(EDGE_ALL_FLAGS + 1);
+ e->flags &= ~saved_irr_mask;
}
}
- free (irreds);
}
/* Check the recorded loop exits. */
edge e;
edge_iterator ei;
- gcc_assert (loops_state_satisfies_p (LOOPS_HAVE_PREHEADERS));
+ gcc_assert (loops_state_satisfies_p (LOOPS_HAVE_PREHEADERS)
+ && ! loops_state_satisfies_p (LOOPS_MAY_HAVE_MULTIPLE_LATCHES));
FOR_EACH_EDGE (e, ei, loop->header->preds)
if (e->src != loop->latch)
break;
+ if (! e)
+ {
+ gcc_assert (! loop_outer (loop));
+ return single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun));
+ }
+
return e;
}
/* Return location corresponding to the loop control condition if possible. */
-location_t
+dump_user_location_t
get_loop_location (struct loop *loop)
{
rtx_insn *insn = NULL;
FOR_BB_INSNS_REVERSE (desc->in_edge->src, insn)
{
if (INSN_P (insn) && INSN_HAS_LOCATION (insn))
- return INSN_LOCATION (insn);
+ return insn;
}
}
/* If loop has a single exit, then the loop control branch
FOR_BB_INSNS_REVERSE (exit->src, insn)
{
if (INSN_P (insn) && INSN_HAS_LOCATION (insn))
- return INSN_LOCATION (insn);
+ return insn;
}
}
/* Next check the latch, to see if it is non-empty. */
FOR_BB_INSNS_REVERSE (loop->latch, insn)
{
if (INSN_P (insn) && INSN_HAS_LOCATION (insn))
- return INSN_LOCATION (insn);
+ return insn;
}
/* Finally, if none of the above identifies the loop control branch,
return the first location in the loop header. */
FOR_BB_INSNS (loop->header, insn)
{
if (INSN_P (insn) && INSN_HAS_LOCATION (insn))
- return INSN_LOCATION (insn);
+ return insn;
}
/* If all else fails, simply return the current function location. */
- return DECL_SOURCE_LOCATION (current_function_decl);
+ return dump_user_location_t::from_function_decl (current_function_decl);
}
/* Records that every statement in LOOP is executed I_BOUND times.
{
loop->any_upper_bound = true;
loop->nb_iterations_upper_bound = i_bound;
+ if (!loop->any_likely_upper_bound)
+ {
+ loop->any_likely_upper_bound = true;
+ loop->nb_iterations_likely_upper_bound = i_bound;
+ }
}
if (realistic
&& (!loop->any_estimate
loop->any_estimate = true;
loop->nb_iterations_estimate = i_bound;
}
+ if (!realistic
+ && (!loop->any_likely_upper_bound
+ || wi::ltu_p (i_bound, loop->nb_iterations_likely_upper_bound)))
+ {
+ loop->any_likely_upper_bound = true;
+ loop->nb_iterations_likely_upper_bound = i_bound;
+ }
/* If an upper bound is smaller than the realistic estimate of the
number of iterations, use the upper bound instead. */
&& wi::ltu_p (loop->nb_iterations_upper_bound,
loop->nb_iterations_estimate))
loop->nb_iterations_estimate = loop->nb_iterations_upper_bound;
+ if (loop->any_upper_bound
+ && loop->any_likely_upper_bound
+ && wi::ltu_p (loop->nb_iterations_upper_bound,
+ loop->nb_iterations_likely_upper_bound))
+ loop->nb_iterations_likely_upper_bound = loop->nb_iterations_upper_bound;
}
/* Similar to get_estimated_loop_iterations, but returns the estimate only
return snit < 0 ? -1 : snit;
}
+/* Returns an likely upper bound on the number of executions of statements
+ in the LOOP. For statements before the loop exit, this exceeds
+ the number of execution of the latch by one. */
+
+HOST_WIDE_INT
+likely_max_stmt_executions_int (struct loop *loop)
+{
+ HOST_WIDE_INT nit = get_likely_max_loop_iterations_int (loop);
+ HOST_WIDE_INT snit;
+
+ if (nit == -1)
+ return -1;
+
+ snit = (HOST_WIDE_INT) ((unsigned HOST_WIDE_INT) nit + 1);
+
+ /* If the computation overflows, return -1. */
+ return snit < 0 ? -1 : snit;
+}
+
/* Sets NIT to the estimated number of executions of the latch of the
LOOP. If we have no reliable estimate, the function returns false, otherwise
returns true. */
profile. */
if (!loop->any_estimate)
{
- if (loop->header->count)
+ if (loop->header->count.reliable_p ())
{
*nit = gcov_type_to_wide_int
(expected_loop_iterations_unbounded (loop) + 1);
false, otherwise returns true. */
bool
-get_max_loop_iterations (struct loop *loop, widest_int *nit)
+get_max_loop_iterations (const struct loop *loop, widest_int *nit)
{
if (!loop->any_upper_bound)
return false;
on the number of iterations of LOOP could not be derived, returns -1. */
HOST_WIDE_INT
-get_max_loop_iterations_int (struct loop *loop)
+get_max_loop_iterations_int (const struct loop *loop)
{
widest_int nit;
HOST_WIDE_INT hwi_nit;
return hwi_nit < 0 ? -1 : hwi_nit;
}
+/* Sets NIT to an upper bound for the maximum number of executions of the
+ latch of the LOOP. If we have no reliable estimate, the function returns
+ false, otherwise returns true. */
+
+bool
+get_likely_max_loop_iterations (struct loop *loop, widest_int *nit)
+{
+ if (!loop->any_likely_upper_bound)
+ return false;
+
+ *nit = loop->nb_iterations_likely_upper_bound;
+ return true;
+}
+
+/* Similar to get_max_loop_iterations, but returns the estimate only
+ if it fits to HOST_WIDE_INT. If this is not the case, or the estimate
+ on the number of iterations of LOOP could not be derived, returns -1. */
+
+HOST_WIDE_INT
+get_likely_max_loop_iterations_int (struct loop *loop)
+{
+ widest_int nit;
+ HOST_WIDE_INT hwi_nit;
+
+ if (!get_likely_max_loop_iterations (loop, &nit))
+ return -1;
+
+ if (!wi::fits_shwi_p (nit))
+ return -1;
+ hwi_nit = nit.to_shwi ();
+
+ return hwi_nit < 0 ? -1 : hwi_nit;
+}
+
/* Returns the loop depth of the loop BB belongs to. */
int