On Wed, 14 Jun 2017, Richard Biener wrote:
>
> niter estimates are not kept up-to-date (they reference gimple stmts
> and trees) in the keep-loop-stuff infrastructure so similar to the
> SCEV cache we rely on people freeing it after passes.
>
> The following brings us a step closer to that by freeing them whenever
> SCEV is invalidated (we only compute them when SCEV is active) plus
> removing the odd record-bounds pass that just computes them, leaving
> scavenging to following passes.
>
> Bootstrap and regtest running on x86_64-unknown-linux-gnu.
Some awkward interactions with peeling means I'm installing the
following less aggressive variant.
Bootstrapped and tested on x86_64-unknown-linux-gnu, applied.
Richard.
2017-06-16 Richard Biener <rguent...@suse.de>
PR tree-optimization/81090
* passes.def (pass_record_bounds): Remove.
* tree-pass.h (make_pass_record_bounds): Likewise.
* tree-ssa-loop.c (pass_data_record_bounds, pass_record_bounds,
make_pass_record_bounds): Likewise.
* tree-ssa-loop-ivcanon.c (canonicalize_induction_variables): Do
not free niter estimates at the beginning but at the end.
* tree-scalar-evolution.c (scev_finalize): Free niter estimates.
* gcc.dg/graphite/pr81090.c: New testcase.
Index: gcc/passes.def
===================================================================
--- gcc/passes.def (revision 249246)
+++ gcc/passes.def (working copy)
@@ -276,7 +276,6 @@ along with GCC; see the file COPYING3.
/* All unswitching, final value replacement and splitting can expose
empty loops. Remove them now. */
NEXT_PASS (pass_cd_dce);
- NEXT_PASS (pass_record_bounds);
NEXT_PASS (pass_iv_canon);
NEXT_PASS (pass_loop_distribution);
NEXT_PASS (pass_copy_prop);
Index: gcc/testsuite/gcc.dg/graphite/pr81090.c
===================================================================
--- gcc/testsuite/gcc.dg/graphite/pr81090.c (nonexistent)
+++ gcc/testsuite/gcc.dg/graphite/pr81090.c (working copy)
@@ -0,0 +1,27 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -floop-nest-optimize" } */
+
+int x3, za;
+int hg[1];
+
+void
+yw (int dq)
+{
+ const int r7 = 2;
+
+ while (dq < 1)
+ {
+ for (x3 = 0; x3 < r7; ++x3)
+ for (za = 0; za < r7; ++za)
+ hg[1] = 0;
+ ++dq;
+ }
+
+ x3 = 0;
+ while (x3 < r7)
+ {
+ ++x3;
+ if (x3 == 0)
+ break;
+ }
+}
Index: gcc/tree-pass.h
===================================================================
--- gcc/tree-pass.h (revision 249246)
+++ gcc/tree-pass.h (working copy)
@@ -373,7 +373,6 @@ extern gimple_opt_pass *make_pass_predco
extern gimple_opt_pass *make_pass_iv_canon (gcc::context *ctxt);
extern gimple_opt_pass *make_pass_scev_cprop (gcc::context *ctxt);
extern gimple_opt_pass *make_pass_empty_loop (gcc::context *ctxt);
-extern gimple_opt_pass *make_pass_record_bounds (gcc::context *ctxt);
extern gimple_opt_pass *make_pass_graphite (gcc::context *ctxt);
extern gimple_opt_pass *make_pass_graphite_transforms (gcc::context *ctxt);
extern gimple_opt_pass *make_pass_if_conversion (gcc::context *ctxt);
Index: gcc/tree-scalar-evolution.c
===================================================================
--- gcc/tree-scalar-evolution.c (revision 249246)
+++ gcc/tree-scalar-evolution.c (working copy)
@@ -3636,6 +3636,7 @@ scev_finalize (void)
return;
scalar_evolution_info->empty ();
scalar_evolution_info = NULL;
+ free_numbers_of_iterations_estimates (cfun);
}
/* Returns true if the expression EXPR is considered to be too expensive
Index: gcc/tree-ssa-loop-ivcanon.c
===================================================================
--- gcc/tree-ssa-loop-ivcanon.c (revision 249246)
+++ gcc/tree-ssa-loop-ivcanon.c (working copy)
@@ -1212,7 +1212,6 @@ canonicalize_induction_variables (void)
bool irred_invalidated = false;
bitmap loop_closed_ssa_invalidated = BITMAP_ALLOC (NULL);
- free_numbers_of_iterations_estimates (cfun);
estimate_numbers_of_iterations ();
FOR_EACH_LOOP (loop, LI_FROM_INNERMOST)
@@ -1230,6 +1229,7 @@ canonicalize_induction_variables (void)
/* Clean up the information about numbers of iterations, since brute force
evaluation could reveal new information. */
+ free_numbers_of_iterations_estimates (cfun);
scev_reset ();
if (!bitmap_empty_p (loop_closed_ssa_invalidated))
Index: gcc/tree-ssa-loop.c
===================================================================
--- gcc/tree-ssa-loop.c (revision 249246)
+++ gcc/tree-ssa-loop.c (working copy)
@@ -459,54 +459,6 @@ make_pass_scev_cprop (gcc::context *ctxt
return new pass_scev_cprop (ctxt);
}
-/* Record bounds on numbers of iterations of loops. */
-
-namespace {
-
-const pass_data pass_data_record_bounds =
-{
- GIMPLE_PASS, /* type */
- "*record_bounds", /* name */
- OPTGROUP_NONE, /* optinfo_flags */
- TV_TREE_LOOP_BOUNDS, /* tv_id */
- ( PROP_cfg | PROP_ssa ), /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- 0, /* todo_flags_start */
- 0, /* todo_flags_finish */
-};
-
-class pass_record_bounds : public gimple_opt_pass
-{
-public:
- pass_record_bounds (gcc::context *ctxt)
- : gimple_opt_pass (pass_data_record_bounds, ctxt)
- {}
-
- /* opt_pass methods: */
- virtual unsigned int execute (function *);
-
-}; // class pass_record_bounds
-
-unsigned int
-pass_record_bounds::execute (function *fun)
-{
- if (number_of_loops (fun) <= 1)
- return 0;
-
- estimate_numbers_of_iterations ();
- scev_reset ();
- return 0;
-}
-
-} // anon namespace
-
-gimple_opt_pass *
-make_pass_record_bounds (gcc::context *ctxt)
-{
- return new pass_record_bounds (ctxt);
-}
-
/* Induction variable optimizations. */
namespace {
