8059241: C2: Excessive RemoveUseless passes during incremental inlining
Reviewed-by: roland, shade
--- a/src/hotspot/share/opto/callGenerator.cpp Thu Jan 31 13:36:31 2019 -0800
+++ b/src/hotspot/share/opto/callGenerator.cpp Thu Jan 31 17:48:25 2019 -0800
@@ -459,7 +459,7 @@
C->set_has_loops(C->has_loops() || _inline_cg->method()->has_loops());
C->env()->notice_inlined_method(_inline_cg->method());
C->set_inlining_progress(true);
-
+ C->set_do_cleanup(kit.stopped()); // path is dead; needs cleanup
kit.replace_call(call, result, true);
}
--- a/src/hotspot/share/opto/castnode.cpp Thu Jan 31 13:36:31 2019 -0800
+++ b/src/hotspot/share/opto/castnode.cpp Thu Jan 31 17:48:25 2019 -0800
@@ -410,11 +410,11 @@
Node* dispX,
bool negate = false) {
if (negate) {
- dispX = new SubXNode(phase->MakeConX(0), phase->transform(dispX));
+ dispX = phase->transform(new SubXNode(phase->MakeConX(0), dispX));
}
return new AddPNode(phase->C->top(),
phase->transform(new CastX2PNode(base)),
- phase->transform(dispX));
+ dispX);
}
Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) {
--- a/src/hotspot/share/opto/compile.cpp Thu Jan 31 13:36:31 2019 -0800
+++ b/src/hotspot/share/opto/compile.cpp Thu Jan 31 17:48:25 2019 -0800
@@ -648,6 +648,7 @@
_orig_pc_slot_offset_in_bytes(0),
_inlining_progress(false),
_inlining_incrementally(false),
+ _do_cleanup(false),
_has_reserved_stack_access(target->has_reserved_stack_access()),
#ifndef PRODUCT
_trace_opto_output(directive->TraceOptoOutputOption),
@@ -2051,52 +2052,49 @@
}
_boxing_late_inlines.trunc_to(0);
- {
- ResourceMark rm;
- PhaseRemoveUseless pru(gvn, for_igvn());
- }
-
- igvn = PhaseIterGVN(gvn);
- igvn.optimize();
-
- set_inlining_progress(false);
+ inline_incrementally_cleanup(igvn);
+
set_inlining_incrementally(false);
}
}
-void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
+bool Compile::inline_incrementally_one() {
assert(IncrementalInline, "incremental inlining should be on");
- PhaseGVN* gvn = initial_gvn();
+
+ TracePhase tp("incrementalInline_inline", &timers[_t_incrInline_inline]);
+ set_inlining_progress(false);
+ set_do_cleanup(false);
+ int i = 0;
+ for (; i <_late_inlines.length() && !inlining_progress(); i++) {
+ CallGenerator* cg = _late_inlines.at(i);
+ _late_inlines_pos = i+1;
+ cg->do_late_inline();
+ if (failing()) return false;
+ }
+ int j = 0;
+ for (; i < _late_inlines.length(); i++, j++) {
+ _late_inlines.at_put(j, _late_inlines.at(i));
+ }
+ _late_inlines.trunc_to(j);
+ assert(inlining_progress() || _late_inlines.length() == 0, "");
+
+ bool needs_cleanup = do_cleanup() || over_inlining_cutoff();
set_inlining_progress(false);
- for_igvn()->clear();
- gvn->replace_with(&igvn);
-
- {
- TracePhase tp("incrementalInline_inline", &timers[_t_incrInline_inline]);
- int i = 0;
- for (; i <_late_inlines.length() && !inlining_progress(); i++) {
- CallGenerator* cg = _late_inlines.at(i);
- _late_inlines_pos = i+1;
- cg->do_late_inline();
- if (failing()) return;
- }
- int j = 0;
- for (; i < _late_inlines.length(); i++, j++) {
- _late_inlines.at_put(j, _late_inlines.at(i));
- }
- _late_inlines.trunc_to(j);
- }
-
+ set_do_cleanup(false);
+ return (_late_inlines.length() > 0) && !needs_cleanup;
+}
+
+void Compile::inline_incrementally_cleanup(PhaseIterGVN& igvn) {
{
TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
ResourceMark rm;
- PhaseRemoveUseless pru(gvn, for_igvn());
+ PhaseRemoveUseless pru(initial_gvn(), for_igvn());
}
-
{
TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
- igvn = PhaseIterGVN(gvn);
+ igvn = PhaseIterGVN(initial_gvn());
+ igvn.optimize();
}
}
@@ -2104,14 +2102,10 @@
void Compile::inline_incrementally(PhaseIterGVN& igvn) {
TracePhase tp("incrementalInline", &timers[_t_incrInline]);
- PhaseGVN* gvn = initial_gvn();
-
set_inlining_incrementally(true);
- set_inlining_progress(true);
uint low_live_nodes = 0;
- while(inlining_progress() && _late_inlines.length() > 0) {
-
+ while (_late_inlines.length() > 0) {
if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
TracePhase tp("incrementalInline_ideal", &timers[_t_incrInline_ideal]);
@@ -2125,22 +2119,23 @@
}
if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
- break;
+ break; // finish
}
}
- inline_incrementally_one(igvn);
-
- if (failing()) return;
-
- {
- TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
- igvn.optimize();
+ for_igvn()->clear();
+ initial_gvn()->replace_with(&igvn);
+
+ while (inline_incrementally_one()) {
+ assert(!failing(), "inconsistent");
}
if (failing()) return;
+
+ inline_incrementally_cleanup(igvn);
+
+ if (failing()) return;
}
-
assert( igvn._worklist.size() == 0, "should be done with igvn" );
if (_string_late_inlines.length() > 0) {
@@ -2152,17 +2147,7 @@
if (failing()) return;
- {
- TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
- ResourceMark rm;
- PhaseRemoveUseless pru(initial_gvn(), for_igvn());
- }
-
- {
- TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
- igvn = PhaseIterGVN(gvn);
- igvn.optimize();
- }
+ inline_incrementally_cleanup(igvn);
}
set_inlining_incrementally(false);
--- a/src/hotspot/share/opto/compile.hpp Thu Jan 31 13:36:31 2019 -0800
+++ b/src/hotspot/share/opto/compile.hpp Thu Jan 31 17:48:25 2019 -0800
@@ -383,6 +383,7 @@
int _major_progress; // Count of something big happening
bool _inlining_progress; // progress doing incremental inlining?
bool _inlining_incrementally;// Are we doing incremental inlining (post parse)
+ bool _do_cleanup; // Cleanup is needed before proceeding with incremental inlining
bool _has_loops; // True if the method _may_ have some loops
bool _has_split_ifs; // True if the method _may_ have some split-if
bool _has_unsafe_access; // True if the method _may_ produce faults in unsafe loads or stores.
@@ -653,6 +654,8 @@
int inlining_progress() const { return _inlining_progress; }
void set_inlining_incrementally(bool z) { _inlining_incrementally = z; }
int inlining_incrementally() const { return _inlining_incrementally; }
+ void set_do_cleanup(bool z) { _do_cleanup = z; }
+ int do_cleanup() const { return _do_cleanup; }
void set_major_progress() { _major_progress++; }
void clear_major_progress() { _major_progress = 0; }
int max_inline_size() const { return _max_inline_size; }
@@ -1075,7 +1078,11 @@
if (!inlining_incrementally()) {
return unique() > (uint)NodeCountInliningCutoff;
} else {
- return live_nodes() > (uint)LiveNodeCountInliningCutoff;
+ // Give some room for incremental inlining algorithm to "breathe"
+ // and avoid thrashing when live node count is close to the limit.
+ // Keep in mind that live_nodes() isn't accurate during inlining until
+ // dead node elimination step happens (see Compile::inline_incrementally).
+ return live_nodes() > (uint)LiveNodeCountInliningCutoff * 11 / 10;
}
}
@@ -1083,7 +1090,8 @@
void dec_number_of_mh_late_inlines() { assert(_number_of_mh_late_inlines > 0, "_number_of_mh_late_inlines < 0 !"); _number_of_mh_late_inlines--; }
bool has_mh_late_inlines() const { return _number_of_mh_late_inlines > 0; }
- void inline_incrementally_one(PhaseIterGVN& igvn);
+ bool inline_incrementally_one();
+ void inline_incrementally_cleanup(PhaseIterGVN& igvn);
void inline_incrementally(PhaseIterGVN& igvn);
void inline_string_calls(bool parse_time);
void inline_boxing_calls(PhaseIterGVN& igvn);