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shenandoahSupport.cpp
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shenandoahSupport.cpp
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/*
* Copyright (c) 2015, 2021, Red Hat, Inc. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "classfile/javaClasses.hpp"
#include "gc/shenandoah/c2/shenandoahSupport.hpp"
#include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
#include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
#include "gc/shenandoah/shenandoahForwarding.hpp"
#include "gc/shenandoah/shenandoahHeap.hpp"
#include "gc/shenandoah/shenandoahHeapRegion.hpp"
#include "gc/shenandoah/shenandoahRuntime.hpp"
#include "gc/shenandoah/shenandoahThreadLocalData.hpp"
#include "opto/arraycopynode.hpp"
#include "opto/block.hpp"
#include "opto/callnode.hpp"
#include "opto/castnode.hpp"
#include "opto/movenode.hpp"
#include "opto/phaseX.hpp"
#include "opto/rootnode.hpp"
#include "opto/runtime.hpp"
#include "opto/subnode.hpp"
bool ShenandoahBarrierC2Support::expand(Compile* C, PhaseIterGVN& igvn) {
ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
if ((state->iu_barriers_count() +
state->load_reference_barriers_count()) > 0) {
assert(C->post_loop_opts_phase(), "no loop opts allowed");
C->reset_post_loop_opts_phase(); // ... but we know what we are doing
bool attempt_more_loopopts = ShenandoahLoopOptsAfterExpansion;
C->clear_major_progress();
PhaseIdealLoop::optimize(igvn, LoopOptsShenandoahExpand);
if (C->failing()) return false;
PhaseIdealLoop::verify(igvn);
DEBUG_ONLY(verify_raw_mem(C->root());)
if (attempt_more_loopopts) {
C->set_major_progress();
if (!C->optimize_loops(igvn, LoopOptsShenandoahPostExpand)) {
return false;
}
C->clear_major_progress();
C->process_for_post_loop_opts_igvn(igvn);
}
C->set_post_loop_opts_phase(); // now for real!
}
return true;
}
bool ShenandoahBarrierC2Support::is_gc_state_test(Node* iff, int mask) {
if (!UseShenandoahGC) {
return false;
}
assert(iff->is_If(), "bad input");
if (iff->Opcode() != Op_If) {
return false;
}
Node* bol = iff->in(1);
if (!bol->is_Bool() || bol->as_Bool()->_test._test != BoolTest::ne) {
return false;
}
Node* cmp = bol->in(1);
if (cmp->Opcode() != Op_CmpI) {
return false;
}
Node* in1 = cmp->in(1);
Node* in2 = cmp->in(2);
if (in2->find_int_con(-1) != 0) {
return false;
}
if (in1->Opcode() != Op_AndI) {
return false;
}
in2 = in1->in(2);
if (in2->find_int_con(-1) != mask) {
return false;
}
in1 = in1->in(1);
return is_gc_state_load(in1);
}
bool ShenandoahBarrierC2Support::is_heap_stable_test(Node* iff) {
return is_gc_state_test(iff, ShenandoahHeap::HAS_FORWARDED);
}
bool ShenandoahBarrierC2Support::is_gc_state_load(Node *n) {
if (!UseShenandoahGC) {
return false;
}
if (n->Opcode() != Op_LoadB && n->Opcode() != Op_LoadUB) {
return false;
}
Node* addp = n->in(MemNode::Address);
if (!addp->is_AddP()) {
return false;
}
Node* base = addp->in(AddPNode::Address);
Node* off = addp->in(AddPNode::Offset);
if (base->Opcode() != Op_ThreadLocal) {
return false;
}
if (off->find_intptr_t_con(-1) != in_bytes(ShenandoahThreadLocalData::gc_state_offset())) {
return false;
}
return true;
}
bool ShenandoahBarrierC2Support::has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase) {
assert(phase->is_dominator(stop, start), "bad inputs");
ResourceMark rm;
Unique_Node_List wq;
wq.push(start);
for (uint next = 0; next < wq.size(); next++) {
Node *m = wq.at(next);
if (m == stop) {
continue;
}
if (m->is_SafePoint() && !m->is_CallLeaf()) {
return true;
}
if (m->is_Region()) {
for (uint i = 1; i < m->req(); i++) {
wq.push(m->in(i));
}
} else {
wq.push(m->in(0));
}
}
return false;
}
#ifdef ASSERT
bool ShenandoahBarrierC2Support::verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used) {
assert(phis.size() == 0, "");
while (true) {
if (in->bottom_type() == TypePtr::NULL_PTR) {
if (trace) {tty->print_cr("NULL");}
} else if (!in->bottom_type()->make_ptr()->make_oopptr()) {
if (trace) {tty->print_cr("Non oop");}
} else {
if (in->is_ConstraintCast()) {
in = in->in(1);
continue;
} else if (in->is_AddP()) {
assert(!in->in(AddPNode::Address)->is_top(), "no raw memory access");
in = in->in(AddPNode::Address);
continue;
} else if (in->is_Con()) {
if (trace) {
tty->print("Found constant");
in->dump();
}
} else if (in->Opcode() == Op_Parm) {
if (trace) {
tty->print("Found argument");
}
} else if (in->Opcode() == Op_CreateEx) {
if (trace) {
tty->print("Found create-exception");
}
} else if (in->Opcode() == Op_LoadP && in->adr_type() == TypeRawPtr::BOTTOM) {
if (trace) {
tty->print("Found raw LoadP (OSR argument?)");
}
} else if (in->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
if (t == ShenandoahOopStore) {
uint i = 0;
for (; i < phis.size(); i++) {
Node* n = phis.node_at(i);
if (n->Opcode() == Op_ShenandoahIUBarrier) {
break;
}
}
if (i == phis.size()) {
return false;
}
}
barriers_used.push(in);
if (trace) {tty->print("Found barrier"); in->dump();}
} else if (in->Opcode() == Op_ShenandoahIUBarrier) {
if (t != ShenandoahOopStore) {
in = in->in(1);
continue;
}
if (trace) {tty->print("Found enqueue barrier"); in->dump();}
phis.push(in, in->req());
in = in->in(1);
continue;
} else if (in->is_Proj() && in->in(0)->is_Allocate()) {
if (trace) {
tty->print("Found alloc");
in->in(0)->dump();
}
} else if (in->is_Proj() && (in->in(0)->Opcode() == Op_CallStaticJava || in->in(0)->Opcode() == Op_CallDynamicJava)) {
if (trace) {
tty->print("Found Java call");
}
} else if (in->is_Phi()) {
if (!visited.test_set(in->_idx)) {
if (trace) {tty->print("Pushed phi:"); in->dump();}
phis.push(in, 2);
in = in->in(1);
continue;
}
if (trace) {tty->print("Already seen phi:"); in->dump();}
} else if (in->Opcode() == Op_CMoveP || in->Opcode() == Op_CMoveN) {
if (!visited.test_set(in->_idx)) {
if (trace) {tty->print("Pushed cmovep:"); in->dump();}
phis.push(in, CMoveNode::IfTrue);
in = in->in(CMoveNode::IfFalse);
continue;
}
if (trace) {tty->print("Already seen cmovep:"); in->dump();}
} else if (in->Opcode() == Op_EncodeP || in->Opcode() == Op_DecodeN) {
in = in->in(1);
continue;
} else {
return false;
}
}
bool cont = false;
while (phis.is_nonempty()) {
uint idx = phis.index();
Node* phi = phis.node();
if (idx >= phi->req()) {
if (trace) {tty->print("Popped phi:"); phi->dump();}
phis.pop();
continue;
}
if (trace) {tty->print("Next entry(%d) for phi:", idx); phi->dump();}
in = phi->in(idx);
phis.set_index(idx+1);
cont = true;
break;
}
if (!cont) {
break;
}
}
return true;
}
void ShenandoahBarrierC2Support::report_verify_failure(const char* msg, Node* n1, Node* n2) {
if (n1 != NULL) {
n1->dump(+10);
}
if (n2 != NULL) {
n2->dump(+10);
}
fatal("%s", msg);
}
void ShenandoahBarrierC2Support::verify(RootNode* root) {
ResourceMark rm;
Unique_Node_List wq;
GrowableArray<Node*> barriers;
Unique_Node_List barriers_used;
Node_Stack phis(0);
VectorSet visited;
const bool trace = false;
const bool verify_no_useless_barrier = false;
wq.push(root);
for (uint next = 0; next < wq.size(); next++) {
Node *n = wq.at(next);
if (n->is_Load()) {
const bool trace = false;
if (trace) {tty->print("Verifying"); n->dump();}
if (n->Opcode() == Op_LoadRange || n->Opcode() == Op_LoadKlass || n->Opcode() == Op_LoadNKlass) {
if (trace) {tty->print_cr("Load range/klass");}
} else {
const TypePtr* adr_type = n->as_Load()->adr_type();
if (adr_type->isa_oopptr() && adr_type->is_oopptr()->offset() == oopDesc::mark_offset_in_bytes()) {
if (trace) {tty->print_cr("Mark load");}
} else if (adr_type->isa_instptr() &&
adr_type->is_instptr()->klass()->is_subtype_of(Compile::current()->env()->Reference_klass()) &&
adr_type->is_instptr()->offset() == java_lang_ref_Reference::referent_offset()) {
if (trace) {tty->print_cr("Reference.get()");}
} else if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahLoad, trace, barriers_used)) {
report_verify_failure("Shenandoah verification: Load should have barriers", n);
}
}
} else if (n->is_Store()) {
const bool trace = false;
if (trace) {tty->print("Verifying"); n->dump();}
if (n->in(MemNode::ValueIn)->bottom_type()->make_oopptr()) {
Node* adr = n->in(MemNode::Address);
bool verify = true;
if (adr->is_AddP() && adr->in(AddPNode::Base)->is_top()) {
adr = adr->in(AddPNode::Address);
if (adr->is_AddP()) {
assert(adr->in(AddPNode::Base)->is_top(), "");
adr = adr->in(AddPNode::Address);
if (adr->Opcode() == Op_LoadP &&
adr->in(MemNode::Address)->in(AddPNode::Base)->is_top() &&
adr->in(MemNode::Address)->in(AddPNode::Address)->Opcode() == Op_ThreadLocal &&
adr->in(MemNode::Address)->in(AddPNode::Offset)->find_intptr_t_con(-1) == in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset())) {
if (trace) {tty->print_cr("SATB prebarrier");}
verify = false;
}
}
}
if (verify && !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahIUBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
report_verify_failure("Shenandoah verification: Store should have barriers", n);
}
}
if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
report_verify_failure("Shenandoah verification: Store (address) should have barriers", n);
}
} else if (n->Opcode() == Op_CmpP) {
const bool trace = false;
Node* in1 = n->in(1);
Node* in2 = n->in(2);
if (in1->bottom_type()->isa_oopptr()) {
if (trace) {tty->print("Verifying"); n->dump();}
bool mark_inputs = false;
if (in1->bottom_type() == TypePtr::NULL_PTR || in2->bottom_type() == TypePtr::NULL_PTR ||
(in1->is_Con() || in2->is_Con())) {
if (trace) {tty->print_cr("Comparison against a constant");}
mark_inputs = true;
} else if ((in1->is_CheckCastPP() && in1->in(1)->is_Proj() && in1->in(1)->in(0)->is_Allocate()) ||
(in2->is_CheckCastPP() && in2->in(1)->is_Proj() && in2->in(1)->in(0)->is_Allocate())) {
if (trace) {tty->print_cr("Comparison with newly alloc'ed object");}
mark_inputs = true;
} else {
assert(in2->bottom_type()->isa_oopptr(), "");
if (!verify_helper(in1, phis, visited, ShenandoahStore, trace, barriers_used) ||
!verify_helper(in2, phis, visited, ShenandoahStore, trace, barriers_used)) {
report_verify_failure("Shenandoah verification: Cmp should have barriers", n);
}
}
if (verify_no_useless_barrier &&
mark_inputs &&
(!verify_helper(in1, phis, visited, ShenandoahValue, trace, barriers_used) ||
!verify_helper(in2, phis, visited, ShenandoahValue, trace, barriers_used))) {
phis.clear();
visited.reset();
}
}
} else if (n->is_LoadStore()) {
if (n->in(MemNode::ValueIn)->bottom_type()->make_ptr() &&
!verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahIUBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
report_verify_failure("Shenandoah verification: LoadStore (value) should have barriers", n);
}
if (n->in(MemNode::Address)->bottom_type()->make_oopptr() && !verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
report_verify_failure("Shenandoah verification: LoadStore (address) should have barriers", n);
}
} else if (n->Opcode() == Op_CallLeafNoFP || n->Opcode() == Op_CallLeaf) {
CallNode* call = n->as_Call();
static struct {
const char* name;
struct {
int pos;
verify_type t;
} args[6];
} calls[] = {
"aescrypt_encryptBlock",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"aescrypt_decryptBlock",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"multiplyToLen",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { TypeFunc::Parms+4, ShenandoahStore },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"squareToLen",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone},
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"montgomery_multiply",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
{ TypeFunc::Parms+6, ShenandoahStore }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"montgomery_square",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+5, ShenandoahStore },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"mulAdd",
{ { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"vectorizedMismatch",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"updateBytesCRC32",
{ { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"updateBytesAdler32",
{ { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"updateBytesCRC32C",
{ { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahLoad}, { -1, ShenandoahNone},
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"counterMode_AESCrypt",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
{ TypeFunc::Parms+3, ShenandoahStore }, { TypeFunc::Parms+5, ShenandoahStore }, { TypeFunc::Parms+6, ShenandoahStore } },
"cipherBlockChaining_encryptAESCrypt",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
{ TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"cipherBlockChaining_decryptAESCrypt",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
{ TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"shenandoah_clone_barrier",
{ { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"ghash_processBlocks",
{ { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"sha1_implCompress",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"sha256_implCompress",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"sha512_implCompress",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"sha1_implCompressMB",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"sha256_implCompressMB",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"sha512_implCompressMB",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"encodeBlock",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
"decodeBlock",
{ { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
{ -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
};
if (call->is_call_to_arraycopystub()) {
Node* dest = NULL;
const TypeTuple* args = n->as_Call()->_tf->domain();
for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
if (args->field_at(i)->isa_ptr()) {
j++;
if (j == 2) {
dest = n->in(i);
break;
}
}
}
if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahLoad, trace, barriers_used) ||
!verify_helper(dest, phis, visited, ShenandoahStore, trace, barriers_used)) {
report_verify_failure("Shenandoah verification: ArrayCopy should have barriers", n);
}
} else if (strlen(call->_name) > 5 &&
!strcmp(call->_name + strlen(call->_name) - 5, "_fill")) {
if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahStore, trace, barriers_used)) {
report_verify_failure("Shenandoah verification: _fill should have barriers", n);
}
} else if (!strcmp(call->_name, "shenandoah_wb_pre")) {
// skip
} else {
const int calls_len = sizeof(calls) / sizeof(calls[0]);
int i = 0;
for (; i < calls_len; i++) {
if (!strcmp(calls[i].name, call->_name)) {
break;
}
}
if (i != calls_len) {
const uint args_len = sizeof(calls[0].args) / sizeof(calls[0].args[0]);
for (uint j = 0; j < args_len; j++) {
int pos = calls[i].args[j].pos;
if (pos == -1) {
break;
}
if (!verify_helper(call->in(pos), phis, visited, calls[i].args[j].t, trace, barriers_used)) {
report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
}
}
for (uint j = TypeFunc::Parms; j < call->req(); j++) {
if (call->in(j)->bottom_type()->make_ptr() &&
call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
uint k = 0;
for (; k < args_len && calls[i].args[k].pos != (int)j; k++);
if (k == args_len) {
fatal("arg %d for call %s not covered", j, call->_name);
}
}
}
} else {
for (uint j = TypeFunc::Parms; j < call->req(); j++) {
if (call->in(j)->bottom_type()->make_ptr() &&
call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
fatal("%s not covered", call->_name);
}
}
}
}
} else if (n->Opcode() == Op_ShenandoahIUBarrier || n->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
// skip
} else if (n->is_AddP()
|| n->is_Phi()
|| n->is_ConstraintCast()
|| n->Opcode() == Op_Return
|| n->Opcode() == Op_CMoveP
|| n->Opcode() == Op_CMoveN
|| n->Opcode() == Op_Rethrow
|| n->is_MemBar()
|| n->Opcode() == Op_Conv2B
|| n->Opcode() == Op_SafePoint
|| n->is_CallJava()
|| n->Opcode() == Op_Unlock
|| n->Opcode() == Op_EncodeP
|| n->Opcode() == Op_DecodeN) {
// nothing to do
} else {
static struct {
int opcode;
struct {
int pos;
verify_type t;
} inputs[2];
} others[] = {
Op_FastLock,
{ { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
Op_Lock,
{ { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone} },
Op_ArrayCopy,
{ { ArrayCopyNode::Src, ShenandoahLoad }, { ArrayCopyNode::Dest, ShenandoahStore } },
Op_StrCompressedCopy,
{ { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
Op_StrInflatedCopy,
{ { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
Op_AryEq,
{ { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
Op_StrIndexOf,
{ { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
Op_StrComp,
{ { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
Op_StrEquals,
{ { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
Op_EncodeISOArray,
{ { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
Op_HasNegatives,
{ { 2, ShenandoahLoad }, { -1, ShenandoahNone} },
Op_CastP2X,
{ { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
Op_StrIndexOfChar,
{ { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
};
const int others_len = sizeof(others) / sizeof(others[0]);
int i = 0;
for (; i < others_len; i++) {
if (others[i].opcode == n->Opcode()) {
break;
}
}
uint stop = n->is_Call() ? n->as_Call()->tf()->domain()->cnt() : n->req();
if (i != others_len) {
const uint inputs_len = sizeof(others[0].inputs) / sizeof(others[0].inputs[0]);
for (uint j = 0; j < inputs_len; j++) {
int pos = others[i].inputs[j].pos;
if (pos == -1) {
break;
}
if (!verify_helper(n->in(pos), phis, visited, others[i].inputs[j].t, trace, barriers_used)) {
report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
}
}
for (uint j = 1; j < stop; j++) {
if (n->in(j) != NULL && n->in(j)->bottom_type()->make_ptr() &&
n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
uint k = 0;
for (; k < inputs_len && others[i].inputs[k].pos != (int)j; k++);
if (k == inputs_len) {
fatal("arg %d for node %s not covered", j, n->Name());
}
}
}
} else {
for (uint j = 1; j < stop; j++) {
if (n->in(j) != NULL && n->in(j)->bottom_type()->make_ptr() &&
n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
fatal("%s not covered", n->Name());
}
}
}
}
if (n->is_SafePoint()) {
SafePointNode* sfpt = n->as_SafePoint();
if (verify_no_useless_barrier && sfpt->jvms() != NULL) {
for (uint i = sfpt->jvms()->scloff(); i < sfpt->jvms()->endoff(); i++) {
if (!verify_helper(sfpt->in(i), phis, visited, ShenandoahLoad, trace, barriers_used)) {
phis.clear();
visited.reset();
}
}
}
}
}
if (verify_no_useless_barrier) {
for (int i = 0; i < barriers.length(); i++) {
Node* n = barriers.at(i);
if (!barriers_used.member(n)) {
tty->print("XXX useless barrier"); n->dump(-2);
ShouldNotReachHere();
}
}
}
}
#endif
bool ShenandoahBarrierC2Support::is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase) {
// That both nodes have the same control is not sufficient to prove
// domination, verify that there's no path from d to n
ResourceMark rm;
Unique_Node_List wq;
wq.push(d);
for (uint next = 0; next < wq.size(); next++) {
Node *m = wq.at(next);
if (m == n) {
return false;
}
if (m->is_Phi() && m->in(0)->is_Loop()) {
assert(phase->ctrl_or_self(m->in(LoopNode::EntryControl)) != c, "following loop entry should lead to new control");
} else {
if (m->is_Store() || m->is_LoadStore()) {
// Take anti-dependencies into account
Node* mem = m->in(MemNode::Memory);
for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) {
Node* u = mem->fast_out(i);
if (u->is_Load() && phase->C->can_alias(m->adr_type(), phase->C->get_alias_index(u->adr_type())) &&
phase->ctrl_or_self(u) == c) {
wq.push(u);
}
}
}
for (uint i = 0; i < m->req(); i++) {
if (m->in(i) != NULL && phase->ctrl_or_self(m->in(i)) == c) {
wq.push(m->in(i));
}
}
}
}
return true;
}
bool ShenandoahBarrierC2Support::is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase) {
if (d_c != n_c) {
return phase->is_dominator(d_c, n_c);
}
return is_dominator_same_ctrl(d_c, d, n, phase);
}
Node* next_mem(Node* mem, int alias) {
Node* res = NULL;
if (mem->is_Proj()) {
res = mem->in(0);
} else if (mem->is_SafePoint() || mem->is_MemBar()) {
res = mem->in(TypeFunc::Memory);
} else if (mem->is_Phi()) {
res = mem->in(1);
} else if (mem->is_MergeMem()) {
res = mem->as_MergeMem()->memory_at(alias);
} else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
assert(alias == Compile::AliasIdxRaw, "following raw memory can't lead to a barrier");
res = mem->in(MemNode::Memory);
} else {
#ifdef ASSERT
mem->dump();
#endif
ShouldNotReachHere();
}
return res;
}
Node* ShenandoahBarrierC2Support::no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase) {
Node* iffproj = NULL;
while (c != dom) {
Node* next = phase->idom(c);
assert(next->unique_ctrl_out() == c || c->is_Proj() || c->is_Region(), "multiple control flow out but no proj or region?");
if (c->is_Region()) {
ResourceMark rm;
Unique_Node_List wq;
wq.push(c);
for (uint i = 0; i < wq.size(); i++) {
Node *n = wq.at(i);
if (n == next) {
continue;
}
if (n->is_Region()) {
for (uint j = 1; j < n->req(); j++) {
wq.push(n->in(j));
}
} else {
wq.push(n->in(0));
}
}
for (uint i = 0; i < wq.size(); i++) {
Node *n = wq.at(i);
assert(n->is_CFG(), "");
if (n->is_Multi()) {
for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
Node* u = n->fast_out(j);
if (u->is_CFG()) {
if (!wq.member(u) && !u->as_Proj()->is_uncommon_trap_proj(Deoptimization::Reason_none)) {
return NodeSentinel;
}
}
}
}
}
} else if (c->is_Proj()) {
if (c->is_IfProj()) {
if (c->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) != NULL) {
// continue;
} else {
if (!allow_one_proj) {
return NodeSentinel;
}
if (iffproj == NULL) {
iffproj = c;
} else {
return NodeSentinel;
}
}
} else if (c->Opcode() == Op_JumpProj) {
return NodeSentinel; // unsupported
} else if (c->Opcode() == Op_CatchProj) {
return NodeSentinel; // unsupported
} else if (c->Opcode() == Op_CProj && next->Opcode() == Op_NeverBranch) {
return NodeSentinel; // unsupported
} else {
assert(next->unique_ctrl_out() == c, "unsupported branch pattern");
}
}
c = next;
}
return iffproj;
}
Node* ShenandoahBarrierC2Support::dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase) {
ResourceMark rm;
VectorSet wq;
wq.set(mem->_idx);
mem_ctrl = phase->ctrl_or_self(mem);
while (!phase->is_dominator(mem_ctrl, ctrl) || mem_ctrl == ctrl) {
mem = next_mem(mem, alias);
if (wq.test_set(mem->_idx)) {
return NULL;
}
mem_ctrl = phase->ctrl_or_self(mem);
}
if (mem->is_MergeMem()) {
mem = mem->as_MergeMem()->memory_at(alias);
mem_ctrl = phase->ctrl_or_self(mem);
}
return mem;
}
Node* ShenandoahBarrierC2Support::find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase) {
Node* mem = NULL;
Node* c = ctrl;
do {
if (c->is_Region()) {
for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax && mem == NULL; i++) {
Node* u = c->fast_out(i);
if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
if (u->adr_type() == TypePtr::BOTTOM) {
mem = u;
}
}
}
} else {
if (c->is_Call() && c->as_Call()->adr_type() != NULL) {
CallProjections projs;
c->as_Call()->extract_projections(&projs, true, false);
if (projs.fallthrough_memproj != NULL) {
if (projs.fallthrough_memproj->adr_type() == TypePtr::BOTTOM) {
if (projs.catchall_memproj == NULL) {
mem = projs.fallthrough_memproj;
} else {
if (phase->is_dominator(projs.fallthrough_catchproj, ctrl)) {
mem = projs.fallthrough_memproj;
} else {
assert(phase->is_dominator(projs.catchall_catchproj, ctrl), "one proj must dominate barrier");
mem = projs.catchall_memproj;
}
}
}
} else {
Node* proj = c->as_Call()->proj_out(TypeFunc::Memory);
if (proj != NULL &&
proj->adr_type() == TypePtr::BOTTOM) {
mem = proj;
}
}
} else {
for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
Node* u = c->fast_out(i);
if (u->is_Proj() &&
u->bottom_type() == Type::MEMORY &&
u->adr_type() == TypePtr::BOTTOM) {
assert(c->is_SafePoint() || c->is_MemBar() || c->is_Start(), "");
assert(mem == NULL, "only one proj");
mem = u;
}
}
assert(!c->is_Call() || c->as_Call()->adr_type() != NULL || mem == NULL, "no mem projection expected");
}
}
c = phase->idom(c);
} while (mem == NULL);
return mem;
}
void ShenandoahBarrierC2Support::follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase) {
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
Node* u = n->fast_out(i);
if (!u->is_CFG() && phase->get_ctrl(u) == ctrl && (!u->is_Phi() || !u->in(0)->is_Loop() || u->in(LoopNode::LoopBackControl) != n)) {
uses.push(u);
}
}
}
static void hide_strip_mined_loop(OuterStripMinedLoopNode* outer, CountedLoopNode* inner, PhaseIdealLoop* phase) {
OuterStripMinedLoopEndNode* le = inner->outer_loop_end();
Node* new_outer = new LoopNode(outer->in(LoopNode::EntryControl), outer->in(LoopNode::LoopBackControl));
phase->register_control(new_outer, phase->get_loop(outer), outer->in(LoopNode::EntryControl));
Node* new_le = new IfNode(le->in(0), le->in(1), le->_prob, le->_fcnt);
phase->register_control(new_le, phase->get_loop(le), le->in(0));
phase->lazy_replace(outer, new_outer);
phase->lazy_replace(le, new_le);
inner->clear_strip_mined();
}
void ShenandoahBarrierC2Support::test_gc_state(Node*& ctrl, Node* raw_mem, Node*& test_fail_ctrl,
PhaseIdealLoop* phase, int flags) {
PhaseIterGVN& igvn = phase->igvn();
Node* old_ctrl = ctrl;
Node* thread = new ThreadLocalNode();
Node* gc_state_offset = igvn.MakeConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
Node* gc_state_addr = new AddPNode(phase->C->top(), thread, gc_state_offset);
Node* gc_state = new LoadBNode(old_ctrl, raw_mem, gc_state_addr,
DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(NULL),
TypeInt::BYTE, MemNode::unordered);
Node* gc_state_and = new AndINode(gc_state, igvn.intcon(flags));
Node* gc_state_cmp = new CmpINode(gc_state_and, igvn.zerocon(T_INT));
Node* gc_state_bool = new BoolNode(gc_state_cmp, BoolTest::ne);
IfNode* gc_state_iff = new IfNode(old_ctrl, gc_state_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
ctrl = new IfTrueNode(gc_state_iff);
test_fail_ctrl = new IfFalseNode(gc_state_iff);
IdealLoopTree* loop = phase->get_loop(old_ctrl);
phase->register_control(gc_state_iff, loop, old_ctrl);
phase->register_control(ctrl, loop, gc_state_iff);
phase->register_control(test_fail_ctrl, loop, gc_state_iff);
phase->register_new_node(thread, old_ctrl);
phase->register_new_node(gc_state_addr, old_ctrl);
phase->register_new_node(gc_state, old_ctrl);
phase->register_new_node(gc_state_and, old_ctrl);
phase->register_new_node(gc_state_cmp, old_ctrl);
phase->register_new_node(gc_state_bool, old_ctrl);
phase->set_ctrl(gc_state_offset, phase->C->root());
assert(is_gc_state_test(gc_state_iff, flags), "Should match the shape");
}
void ShenandoahBarrierC2Support::test_null(Node*& ctrl, Node* val, Node*& null_ctrl, PhaseIdealLoop* phase) {
Node* old_ctrl = ctrl;
PhaseIterGVN& igvn = phase->igvn();
const Type* val_t = igvn.type(val);
if (val_t->meet(TypePtr::NULL_PTR) == val_t) {
Node* null_cmp = new CmpPNode(val, igvn.zerocon(T_OBJECT));
Node* null_test = new BoolNode(null_cmp, BoolTest::ne);
IfNode* null_iff = new IfNode(old_ctrl, null_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
ctrl = new IfTrueNode(null_iff);
null_ctrl = new IfFalseNode(null_iff);
IdealLoopTree* loop = phase->get_loop(old_ctrl);
phase->register_control(null_iff, loop, old_ctrl);
phase->register_control(ctrl, loop, null_iff);
phase->register_control(null_ctrl, loop, null_iff);
phase->register_new_node(null_cmp, old_ctrl);
phase->register_new_node(null_test, old_ctrl);
}
}
void ShenandoahBarrierC2Support::test_in_cset(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase) {
Node* old_ctrl = ctrl;
PhaseIterGVN& igvn = phase->igvn();
Node* raw_val = new CastP2XNode(old_ctrl, val);
Node* cset_idx = new URShiftXNode(raw_val, igvn.intcon(ShenandoahHeapRegion::region_size_bytes_shift_jint()));
// Figure out the target cset address with raw pointer math.
// This avoids matching AddP+LoadB that would emit inefficient code.
// See JDK-8245465.
Node* cset_addr_ptr = igvn.makecon(TypeRawPtr::make(ShenandoahHeap::in_cset_fast_test_addr()));
Node* cset_addr = new CastP2XNode(old_ctrl, cset_addr_ptr);
Node* cset_load_addr = new AddXNode(cset_addr, cset_idx);
Node* cset_load_ptr = new CastX2PNode(cset_load_addr);
Node* cset_load = new LoadBNode(old_ctrl, raw_mem, cset_load_ptr,
DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(NULL),
TypeInt::BYTE, MemNode::unordered);
Node* cset_cmp = new CmpINode(cset_load, igvn.zerocon(T_INT));
Node* cset_bool = new BoolNode(cset_cmp, BoolTest::ne);
IfNode* cset_iff = new IfNode(old_ctrl, cset_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
ctrl = new IfTrueNode(cset_iff);
not_cset_ctrl = new IfFalseNode(cset_iff);
IdealLoopTree *loop = phase->get_loop(old_ctrl);
phase->register_control(cset_iff, loop, old_ctrl);
phase->register_control(ctrl, loop, cset_iff);
phase->register_control(not_cset_ctrl, loop, cset_iff);
phase->set_ctrl(cset_addr_ptr, phase->C->root());
phase->register_new_node(raw_val, old_ctrl);
phase->register_new_node(cset_idx, old_ctrl);
phase->register_new_node(cset_addr, old_ctrl);
phase->register_new_node(cset_load_addr, old_ctrl);
phase->register_new_node(cset_load_ptr, old_ctrl);
phase->register_new_node(cset_load, old_ctrl);
phase->register_new_node(cset_cmp, old_ctrl);
phase->register_new_node(cset_bool, old_ctrl);
}
void ShenandoahBarrierC2Support::call_lrb_stub(Node*& ctrl, Node*& val, Node* load_addr, Node*& result_mem, Node* raw_mem,
DecoratorSet decorators, PhaseIdealLoop* phase) {
IdealLoopTree*loop = phase->get_loop(ctrl);
const TypePtr* obj_type = phase->igvn().type(val)->is_oopptr();
// The slow path stub consumes and produces raw memory in addition
// to the existing memory edges
Node* base = find_bottom_mem(ctrl, phase);
MergeMemNode* mm = MergeMemNode::make(base);
mm->set_memory_at(Compile::AliasIdxRaw, raw_mem);
phase->register_new_node(mm, ctrl);
address calladdr = NULL;
const char* name = NULL;
bool is_strong = ShenandoahBarrierSet::is_strong_access(decorators);
bool is_weak = ShenandoahBarrierSet::is_weak_access(decorators);
bool is_phantom = ShenandoahBarrierSet::is_phantom_access(decorators);
bool is_native = ShenandoahBarrierSet::is_native_access(decorators);
bool is_narrow = UseCompressedOops && !is_native;
if (is_strong) {
if (is_narrow) {
calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow);
name = "load_reference_barrier_strong_narrow";
} else {
calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong);
name = "load_reference_barrier_strong";
}
} else if (is_weak) {
if (is_narrow) {
calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak_narrow);
name = "load_reference_barrier_weak_narrow";
} else {
calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak);
name = "load_reference_barrier_weak";