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src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp
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rev 54995 : 8224675: Late GC barrier insertion for ZGC
Reviewed-by:
*** 20,38 ****
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
#include "precompiled.hpp"
- #include "opto/compile.hpp"
#include "opto/castnode.hpp"
#include "opto/escape.hpp"
#include "opto/graphKit.hpp"
- #include "opto/idealKit.hpp"
#include "opto/loopnode.hpp"
#include "opto/macro.hpp"
#include "opto/node.hpp"
#include "opto/type.hpp"
#include "utilities/macros.hpp"
#include "gc/z/zBarrierSet.hpp"
#include "gc/z/c2/zBarrierSetC2.hpp"
#include "gc/z/zThreadLocalData.hpp"
#include "gc/z/zBarrierSetRuntime.hpp"
--- 20,45 ----
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
#include "precompiled.hpp"
#include "opto/castnode.hpp"
+ #include "opto/compile.hpp"
#include "opto/escape.hpp"
#include "opto/graphKit.hpp"
#include "opto/loopnode.hpp"
+ #include "opto/machnode.hpp"
#include "opto/macro.hpp"
+ #include "opto/memnode.hpp"
+ #include "opto/movenode.hpp"
#include "opto/node.hpp"
+ #include "opto/phase.hpp"
+ #include "opto/phaseX.hpp"
+ #include "opto/rootnode.hpp"
#include "opto/type.hpp"
+ #include "utilities/copy.hpp"
+ #include "utilities/growableArray.hpp"
#include "utilities/macros.hpp"
#include "gc/z/zBarrierSet.hpp"
#include "gc/z/c2/zBarrierSetC2.hpp"
#include "gc/z/zThreadLocalData.hpp"
#include "gc/z/zBarrierSetRuntime.hpp"
*** 82,92 ****
// 3. This step checks for the phi corresponding to an optimized load barrier expansion
if (node->is_Phi()) {
PhiNode* phi = node->as_Phi();
Node* n = phi->in(1);
! if (n != NULL && (n->is_LoadBarrierSlowReg() || n->is_LoadBarrierWeakSlowReg())) {
return true;
}
}
return false;
--- 89,99 ----
// 3. This step checks for the phi corresponding to an optimized load barrier expansion
if (node->is_Phi()) {
PhiNode* phi = node->as_Phi();
Node* n = phi->in(1);
! if (n != NULL && n->is_LoadBarrierSlowReg()) {
return true;
}
}
return false;
*** 119,186 ****
if (node->is_LoadBarrier() && !node->as_LoadBarrier()->has_true_uses()) {
igvn->_worklist.push(node);
}
}
- void ZBarrierSetC2::find_dominating_barriers(PhaseIterGVN& igvn) {
- // Look for dominating barriers on the same address only once all
- // other loop opts are over. Loop opts may cause a safepoint to be
- // inserted between a barrier and its dominating barrier.
- Compile* C = Compile::current();
- ZBarrierSetC2* bs = (ZBarrierSetC2*)BarrierSet::barrier_set()->barrier_set_c2();
- ZBarrierSetC2State* s = bs->state();
- if (s->load_barrier_count() >= 2) {
- Compile::TracePhase tp("idealLoop", &C->timers[Phase::_t_idealLoop]);
- PhaseIdealLoop::optimize(igvn, LoopOptsLastRound);
- if (C->major_progress()) C->print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
- }
- }
-
- void ZBarrierSetC2::add_users_to_worklist(Unique_Node_List* worklist) const {
- // Permanent temporary workaround
- // Loadbarriers may have non-obvious dead uses keeping them alive during parsing. The use is
- // removed by RemoveUseless (after parsing, before optimize) but the barriers won't be added to
- // the worklist. Unless we add them explicitly they are not guaranteed to end up there.
- ZBarrierSetC2State* s = state();
-
- for (int i = 0; i < s->load_barrier_count(); i++) {
- LoadBarrierNode* n = s->load_barrier_node(i);
- worklist->push(n);
- }
- }
-
- const TypeFunc* ZBarrierSetC2::load_barrier_Type() const {
- const Type** fields;
-
- // Create input types (domain)
- fields = TypeTuple::fields(2);
- fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL;
- fields[TypeFunc::Parms+1] = TypeOopPtr::BOTTOM;
- const TypeTuple *domain = TypeTuple::make(TypeFunc::Parms+2, fields);
-
- // Create result type (range)
- fields = TypeTuple::fields(1);
- fields[TypeFunc::Parms+0] = TypeInstPtr::BOTTOM;
- const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+1, fields);
-
- return TypeFunc::make(domain, range);
- }
-
// == LoadBarrierNode ==
LoadBarrierNode::LoadBarrierNode(Compile* C,
Node* c,
Node* mem,
Node* val,
Node* adr,
! bool weak,
! bool writeback,
! bool oop_reload_allowed) :
MultiNode(Number_of_Inputs),
! _weak(weak),
! _writeback(writeback),
! _oop_reload_allowed(oop_reload_allowed) {
init_req(Control, c);
init_req(Memory, mem);
init_req(Oop, val);
init_req(Address, adr);
init_req(Similar, C->top());
--- 126,145 ----
if (node->is_LoadBarrier() && !node->as_LoadBarrier()->has_true_uses()) {
igvn->_worklist.push(node);
}
}
// == LoadBarrierNode ==
LoadBarrierNode::LoadBarrierNode(Compile* C,
Node* c,
Node* mem,
Node* val,
Node* adr,
! bool weak) :
MultiNode(Number_of_Inputs),
! _weak(weak) {
init_req(Control, c);
init_req(Memory, mem);
init_req(Oop, val);
init_req(Address, adr);
init_req(Similar, C->top());
*** 236,245 ****
--- 195,209 ----
return false;
}
LoadBarrierNode* LoadBarrierNode::has_dominating_barrier(PhaseIdealLoop* phase, bool linear_only, bool look_for_similar) {
+ if (is_weak()) {
+ // Weak barriers can't be eliminated
+ return NULL;
+ }
+
Node* val = in(LoadBarrierNode::Oop);
if (in(Similar)->is_Proj() && in(Similar)->in(0)->is_LoadBarrier()) {
LoadBarrierNode* lb = in(Similar)->in(0)->as_LoadBarrier();
assert(lb->in(Address) == in(Address), "");
// Load barrier on Similar edge dominates so if it now has the Oop field it can replace this barrier.
*** 264,274 ****
return u->as_LoadBarrier();
}
}
}
! if (ZVerifyLoadBarriers || can_be_eliminated()) {
return NULL;
}
if (!look_for_similar) {
return NULL;
--- 228,238 ----
return u->as_LoadBarrier();
}
}
}
! if (can_be_eliminated()) {
return NULL;
}
if (!look_for_similar) {
return NULL;
*** 326,335 ****
--- 290,300 ----
return NULL;
}
void LoadBarrierNode::push_dominated_barriers(PhaseIterGVN* igvn) const {
// Change to that barrier may affect a dominated barrier so re-push those
+ assert(!is_weak(), "sanity");
Node* val = in(LoadBarrierNode::Oop);
for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
Node* u = val->fast_out(i);
if (u != this && u->is_LoadBarrier() && u->in(Oop) == val) {
*** 353,369 ****
}
}
}
Node *LoadBarrierNode::Identity(PhaseGVN *phase) {
- if (!phase->C->directive()->ZOptimizeLoadBarriersOption) {
- return this;
- }
-
- bool redundant_addr = false;
LoadBarrierNode* dominating_barrier = has_dominating_barrier(NULL, true, false);
if (dominating_barrier != NULL) {
assert(dominating_barrier->in(Oop) == in(Oop), "");
return dominating_barrier;
}
return this;
--- 318,330 ----
}
}
}
Node *LoadBarrierNode::Identity(PhaseGVN *phase) {
LoadBarrierNode* dominating_barrier = has_dominating_barrier(NULL, true, false);
if (dominating_barrier != NULL) {
+ assert(!is_weak(), "Weak barriers cant be eliminated");
assert(dominating_barrier->in(Oop) == in(Oop), "");
return dominating_barrier;
}
return this;
*** 372,408 ****
Node *LoadBarrierNode::Ideal(PhaseGVN *phase, bool can_reshape) {
if (remove_dead_region(phase, can_reshape)) {
return this;
}
! Node* val = in(Oop);
! Node* mem = in(Memory);
! Node* ctrl = in(Control);
! Node* adr = in(Address);
assert(val->Opcode() != Op_LoadN, "");
if (mem->is_MergeMem()) {
! Node* new_mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
set_req(Memory, new_mem);
if (mem->outcnt() == 0 && can_reshape) {
phase->is_IterGVN()->_worklist.push(mem);
}
-
return this;
}
! bool optimizeLoadBarriers = phase->C->directive()->ZOptimizeLoadBarriersOption;
! LoadBarrierNode* dominating_barrier = optimizeLoadBarriers ? has_dominating_barrier(NULL, !can_reshape, !phase->C->major_progress()) : NULL;
if (dominating_barrier != NULL && dominating_barrier->in(Oop) != in(Oop)) {
assert(in(Address) == dominating_barrier->in(Address), "");
set_req(Similar, dominating_barrier->proj_out(Oop));
return this;
}
! bool eliminate = (optimizeLoadBarriers && !(val->is_Phi() || val->Opcode() == Op_LoadP || val->Opcode() == Op_GetAndSetP || val->is_DecodeN())) ||
! (can_reshape && (dominating_barrier != NULL || !has_true_uses()));
!
if (eliminate) {
if (can_reshape) {
PhaseIterGVN* igvn = phase->is_IterGVN();
Node* out_ctrl = proj_out_or_null(Control);
Node* out_res = proj_out_or_null(Oop);
--- 333,369 ----
Node *LoadBarrierNode::Ideal(PhaseGVN *phase, bool can_reshape) {
if (remove_dead_region(phase, can_reshape)) {
return this;
}
! Node *val = in(Oop);
! Node *mem = in(Memory);
! Node *ctrl = in(Control);
!
assert(val->Opcode() != Op_LoadN, "");
+ assert(val->Opcode() != Op_DecodeN, "");
if (mem->is_MergeMem()) {
! Node *new_mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
set_req(Memory, new_mem);
if (mem->outcnt() == 0 && can_reshape) {
phase->is_IterGVN()->_worklist.push(mem);
}
return this;
}
! LoadBarrierNode *dominating_barrier = NULL;
! if (!is_weak()) {
! dominating_barrier = has_dominating_barrier(NULL, !can_reshape, !phase->C->major_progress());
if (dominating_barrier != NULL && dominating_barrier->in(Oop) != in(Oop)) {
assert(in(Address) == dominating_barrier->in(Address), "");
set_req(Similar, dominating_barrier->proj_out(Oop));
return this;
}
+ }
! bool eliminate = can_reshape && (dominating_barrier != NULL || !has_true_uses());
if (eliminate) {
if (can_reshape) {
PhaseIterGVN* igvn = phase->is_IterGVN();
Node* out_ctrl = proj_out_or_null(Control);
Node* out_res = proj_out_or_null(Oop);
*** 413,440 ****
// That transformation may cause the Similar edge on the load barrier to be invalid
fix_similar_in_uses(igvn);
if (out_res != NULL) {
if (dominating_barrier != NULL) {
igvn->replace_node(out_res, dominating_barrier->proj_out(Oop));
} else {
igvn->replace_node(out_res, val);
}
}
}
-
return new ConINode(TypeInt::ZERO);
}
// If the Similar edge is no longer a load barrier, clear it
Node* similar = in(Similar);
if (!similar->is_top() && !(similar->is_Proj() && similar->in(0)->is_LoadBarrier())) {
set_req(Similar, phase->C->top());
return this;
}
! if (can_reshape) {
// If this barrier is linked through the Similar edge by a
// dominated barrier and both barriers have the same Oop field,
// the dominated barrier can go away, so push it for reprocessing.
// We also want to avoid a barrier to depend on another dominating
// barrier through its Similar edge that itself depend on another
--- 374,401 ----
// That transformation may cause the Similar edge on the load barrier to be invalid
fix_similar_in_uses(igvn);
if (out_res != NULL) {
if (dominating_barrier != NULL) {
+ assert(!is_weak(), "Sanity");
igvn->replace_node(out_res, dominating_barrier->proj_out(Oop));
} else {
igvn->replace_node(out_res, val);
}
}
}
return new ConINode(TypeInt::ZERO);
}
// If the Similar edge is no longer a load barrier, clear it
Node* similar = in(Similar);
if (!similar->is_top() && !(similar->is_Proj() && similar->in(0)->is_LoadBarrier())) {
set_req(Similar, phase->C->top());
return this;
}
! if (can_reshape && !is_weak()) {
// If this barrier is linked through the Similar edge by a
// dominated barrier and both barriers have the same Oop field,
// the dominated barrier can go away, so push it for reprocessing.
// We also want to avoid a barrier to depend on another dominating
// barrier through its Similar edge that itself depend on another
*** 444,457 ****
Node* out_res = proj_out(Oop);
for (DUIterator_Fast imax, i = out_res->fast_outs(imax); i < imax; i++) {
Node* u = out_res->fast_out(i);
if (u->is_LoadBarrier() && u->in(Similar) == out_res &&
(u->in(Oop) == val || !u->in(Similar)->is_top())) {
igvn->_worklist.push(u);
}
}
-
push_dominated_barriers(igvn);
}
return NULL;
}
--- 405,418 ----
Node* out_res = proj_out(Oop);
for (DUIterator_Fast imax, i = out_res->fast_outs(imax); i < imax; i++) {
Node* u = out_res->fast_out(i);
if (u->is_LoadBarrier() && u->in(Similar) == out_res &&
(u->in(Oop) == val || !u->in(Similar)->is_top())) {
+ assert(!u->as_LoadBarrier()->is_weak(), "Sanity");
igvn->_worklist.push(u);
}
}
push_dominated_barriers(igvn);
}
return NULL;
}
*** 477,689 ****
}
}
bool LoadBarrierNode::has_true_uses() const {
Node* out_res = proj_out_or_null(Oop);
! if (out_res == NULL) {
! return false;
! }
!
for (DUIterator_Fast imax, i = out_res->fast_outs(imax); i < imax; i++) {
! Node* u = out_res->fast_out(i);
if (!u->is_LoadBarrier() || u->in(Similar) != out_res) {
return true;
}
}
-
- return false;
- }
-
- // == Accesses ==
-
- Node* ZBarrierSetC2::make_cas_loadbarrier(C2AtomicParseAccess& access) const {
- assert(!UseCompressedOops, "Not allowed");
- CompareAndSwapNode* cas = (CompareAndSwapNode*)access.raw_access();
- PhaseGVN& gvn = access.gvn();
- Compile* C = Compile::current();
- GraphKit* kit = access.kit();
-
- Node* in_ctrl = cas->in(MemNode::Control);
- Node* in_mem = cas->in(MemNode::Memory);
- Node* in_adr = cas->in(MemNode::Address);
- Node* in_val = cas->in(MemNode::ValueIn);
- Node* in_expected = cas->in(LoadStoreConditionalNode::ExpectedIn);
-
- float likely = PROB_LIKELY(0.999);
-
- const TypePtr *adr_type = gvn.type(in_adr)->isa_ptr();
- Compile::AliasType* alias_type = C->alias_type(adr_type);
- int alias_idx = C->get_alias_index(adr_type);
-
- // Outer check - true: continue, false: load and check
- Node* region = new RegionNode(3);
- Node* phi = new PhiNode(region, TypeInt::BOOL);
- Node* phi_mem = new PhiNode(region, Type::MEMORY, adr_type);
-
- // Inner check - is the healed ref equal to the expected
- Node* region2 = new RegionNode(3);
- Node* phi2 = new PhiNode(region2, TypeInt::BOOL);
- Node* phi_mem2 = new PhiNode(region2, Type::MEMORY, adr_type);
-
- // CAS node returns 0 or 1
- Node* cmp = gvn.transform(new CmpINode(cas, kit->intcon(0)));
- Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::ne))->as_Bool();
- IfNode* iff = gvn.transform(new IfNode(in_ctrl, bol, likely, COUNT_UNKNOWN))->as_If();
- Node* then = gvn.transform(new IfTrueNode(iff));
- Node* elsen = gvn.transform(new IfFalseNode(iff));
-
- Node* scmemproj1 = gvn.transform(new SCMemProjNode(cas));
-
- kit->set_memory(scmemproj1, alias_idx);
- phi_mem->init_req(1, scmemproj1);
- phi_mem2->init_req(2, scmemproj1);
-
- // CAS fail - reload and heal oop
- Node* reload = kit->make_load(elsen, in_adr, TypeOopPtr::BOTTOM, T_OBJECT, MemNode::unordered);
- Node* barrier = gvn.transform(new LoadBarrierNode(C, elsen, scmemproj1, reload, in_adr, false, true, false));
- Node* barrierctrl = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Control));
- Node* barrierdata = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Oop));
-
- // Check load
- Node* tmpX = gvn.transform(new CastP2XNode(NULL, barrierdata));
- Node* in_expX = gvn.transform(new CastP2XNode(NULL, in_expected));
- Node* cmp2 = gvn.transform(new CmpXNode(tmpX, in_expX));
- Node *bol2 = gvn.transform(new BoolNode(cmp2, BoolTest::ne))->as_Bool();
- IfNode* iff2 = gvn.transform(new IfNode(barrierctrl, bol2, likely, COUNT_UNKNOWN))->as_If();
- Node* then2 = gvn.transform(new IfTrueNode(iff2));
- Node* elsen2 = gvn.transform(new IfFalseNode(iff2));
-
- // redo CAS
- Node* cas2 = gvn.transform(new CompareAndSwapPNode(elsen2, kit->memory(alias_idx), in_adr, in_val, in_expected, cas->order()));
- Node* scmemproj2 = gvn.transform(new SCMemProjNode(cas2));
- kit->set_control(elsen2);
- kit->set_memory(scmemproj2, alias_idx);
-
- // Merge inner flow - check if healed oop was equal too expected.
- region2->set_req(1, kit->control());
- region2->set_req(2, then2);
- phi2->set_req(1, cas2);
- phi2->set_req(2, kit->intcon(0));
- phi_mem2->init_req(1, scmemproj2);
- kit->set_memory(phi_mem2, alias_idx);
-
- // Merge outer flow - then check if first CAS succeeded
- region->set_req(1, then);
- region->set_req(2, region2);
- phi->set_req(1, kit->intcon(1));
- phi->set_req(2, phi2);
- phi_mem->init_req(2, phi_mem2);
- kit->set_memory(phi_mem, alias_idx);
-
- gvn.transform(region2);
- gvn.transform(phi2);
- gvn.transform(phi_mem2);
- gvn.transform(region);
- gvn.transform(phi);
- gvn.transform(phi_mem);
-
- kit->set_control(region);
- kit->insert_mem_bar(Op_MemBarCPUOrder);
-
- return phi;
- }
-
- Node* ZBarrierSetC2::make_cmpx_loadbarrier(C2AtomicParseAccess& access) const {
- CompareAndExchangePNode* cmpx = (CompareAndExchangePNode*)access.raw_access();
- GraphKit* kit = access.kit();
- PhaseGVN& gvn = kit->gvn();
- Compile* C = Compile::current();
-
- Node* in_ctrl = cmpx->in(MemNode::Control);
- Node* in_mem = cmpx->in(MemNode::Memory);
- Node* in_adr = cmpx->in(MemNode::Address);
- Node* in_val = cmpx->in(MemNode::ValueIn);
- Node* in_expected = cmpx->in(LoadStoreConditionalNode::ExpectedIn);
-
- float likely = PROB_LIKELY(0.999);
-
- const TypePtr *adr_type = cmpx->get_ptr_type();
- Compile::AliasType* alias_type = C->alias_type(adr_type);
- int alias_idx = C->get_alias_index(adr_type);
-
- // Outer check - true: continue, false: load and check
- Node* region = new RegionNode(3);
- Node* phi = new PhiNode(region, adr_type);
-
- // Inner check - is the healed ref equal to the expected
- Node* region2 = new RegionNode(3);
- Node* phi2 = new PhiNode(region2, adr_type);
-
- // Check if cmpx succeeded
- Node* cmp = gvn.transform(new CmpPNode(cmpx, in_expected));
- Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::eq))->as_Bool();
- IfNode* iff = gvn.transform(new IfNode(in_ctrl, bol, likely, COUNT_UNKNOWN))->as_If();
- Node* then = gvn.transform(new IfTrueNode(iff));
- Node* elsen = gvn.transform(new IfFalseNode(iff));
-
- Node* scmemproj1 = gvn.transform(new SCMemProjNode(cmpx));
- kit->set_memory(scmemproj1, alias_idx);
-
- // CAS fail - reload and heal oop
- Node* reload = kit->make_load(elsen, in_adr, TypeOopPtr::BOTTOM, T_OBJECT, MemNode::unordered);
- Node* barrier = gvn.transform(new LoadBarrierNode(C, elsen, scmemproj1, reload, in_adr, false, true, false));
- Node* barrierctrl = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Control));
- Node* barrierdata = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Oop));
-
- // Check load
- Node* tmpX = gvn.transform(new CastP2XNode(NULL, barrierdata));
- Node* in_expX = gvn.transform(new CastP2XNode(NULL, in_expected));
- Node* cmp2 = gvn.transform(new CmpXNode(tmpX, in_expX));
- Node *bol2 = gvn.transform(new BoolNode(cmp2, BoolTest::ne))->as_Bool();
- IfNode* iff2 = gvn.transform(new IfNode(barrierctrl, bol2, likely, COUNT_UNKNOWN))->as_If();
- Node* then2 = gvn.transform(new IfTrueNode(iff2));
- Node* elsen2 = gvn.transform(new IfFalseNode(iff2));
-
- // Redo CAS
- Node* cmpx2 = gvn.transform(new CompareAndExchangePNode(elsen2, kit->memory(alias_idx), in_adr, in_val, in_expected, adr_type, cmpx->get_ptr_type(), cmpx->order()));
- Node* scmemproj2 = gvn.transform(new SCMemProjNode(cmpx2));
- kit->set_control(elsen2);
- kit->set_memory(scmemproj2, alias_idx);
-
- // Merge inner flow - check if healed oop was equal too expected.
- region2->set_req(1, kit->control());
- region2->set_req(2, then2);
- phi2->set_req(1, cmpx2);
- phi2->set_req(2, barrierdata);
-
- // Merge outer flow - then check if first cas succeeded
- region->set_req(1, then);
- region->set_req(2, region2);
- phi->set_req(1, cmpx);
- phi->set_req(2, phi2);
-
- gvn.transform(region2);
- gvn.transform(phi2);
- gvn.transform(region);
- gvn.transform(phi);
-
- kit->set_control(region);
- kit->set_memory(in_mem, alias_idx);
- kit->insert_mem_bar(Op_MemBarCPUOrder);
-
- return phi;
- }
-
- Node* ZBarrierSetC2::load_barrier(GraphKit* kit, Node* val, Node* adr, bool weak, bool writeback, bool oop_reload_allowed) const {
- PhaseGVN& gvn = kit->gvn();
- Node* barrier = new LoadBarrierNode(Compile::current(), kit->control(), kit->memory(TypeRawPtr::BOTTOM), val, adr, weak, writeback, oop_reload_allowed);
- Node* transformed_barrier = gvn.transform(barrier);
-
- if (transformed_barrier->is_LoadBarrier()) {
- if (barrier == transformed_barrier) {
- kit->set_control(gvn.transform(new ProjNode(barrier, LoadBarrierNode::Control)));
- }
- Node* result = gvn.transform(new ProjNode(transformed_barrier, LoadBarrierNode::Oop));
- return result;
- } else {
- return val;
}
}
static bool barrier_needed(C2Access& access) {
return ZBarrierSet::barrier_needed(access.decorators(), access.type());
}
--- 438,456 ----
}
}
bool LoadBarrierNode::has_true_uses() const {
Node* out_res = proj_out_or_null(Oop);
! if (out_res != NULL) {
for (DUIterator_Fast imax, i = out_res->fast_outs(imax); i < imax; i++) {
! Node *u = out_res->fast_out(i);
if (!u->is_LoadBarrier() || u->in(Similar) != out_res) {
return true;
}
}
}
+ return false;
}
static bool barrier_needed(C2Access& access) {
return ZBarrierSet::barrier_needed(access.decorators(), access.type());
}
*** 693,962 ****
if (!barrier_needed(access)) {
return p;
}
bool weak = (access.decorators() & ON_WEAK_OOP_REF) != 0;
-
assert(access.is_parse_access(), "entry not supported at optimization time");
! C2ParseAccess& parse_access = static_cast<C2ParseAccess&>(access);
! GraphKit* kit = parse_access.kit();
! PhaseGVN& gvn = kit->gvn();
! Node* adr = access.addr().node();
! Node* heap_base_oop = access.base();
! bool unsafe = (access.decorators() & C2_UNSAFE_ACCESS) != 0;
! if (unsafe) {
! if (!ZVerifyLoadBarriers) {
! p = load_barrier(kit, p, adr);
! } else {
! if (!TypePtr::NULL_PTR->higher_equal(gvn.type(heap_base_oop))) {
! p = load_barrier(kit, p, adr);
! } else {
! IdealKit ideal(kit);
! IdealVariable res(ideal);
! #define __ ideal.
! __ declarations_done();
! __ set(res, p);
! __ if_then(heap_base_oop, BoolTest::ne, kit->null(), PROB_UNLIKELY(0.999)); {
! kit->sync_kit(ideal);
! p = load_barrier(kit, p, adr);
! __ set(res, p);
! __ sync_kit(kit);
! } __ end_if();
! kit->final_sync(ideal);
! p = __ value(res);
! #undef __
! }
}
return p;
- } else {
- return load_barrier(parse_access.kit(), p, access.addr().node(), weak, true, true);
- }
}
Node* ZBarrierSetC2::atomic_cmpxchg_val_at_resolved(C2AtomicParseAccess& access, Node* expected_val,
Node* new_val, const Type* val_type) const {
Node* result = BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, val_type);
! if (!barrier_needed(access)) {
! return result;
}
!
! access.set_needs_pinning(false);
! return make_cmpx_loadbarrier(access);
}
Node* ZBarrierSetC2::atomic_cmpxchg_bool_at_resolved(C2AtomicParseAccess& access, Node* expected_val,
Node* new_val, const Type* value_type) const {
Node* result = BarrierSetC2::atomic_cmpxchg_bool_at_resolved(access, expected_val, new_val, value_type);
! if (!barrier_needed(access)) {
! return result;
}
!
! Node* load_store = access.raw_access();
! bool weak_cas = (access.decorators() & C2_WEAK_CMPXCHG) != 0;
! bool expected_is_null = (expected_val->get_ptr_type() == TypePtr::NULL_PTR);
!
! if (!expected_is_null) {
! if (weak_cas) {
! access.set_needs_pinning(false);
! load_store = make_cas_loadbarrier(access);
! } else {
! access.set_needs_pinning(false);
! load_store = make_cas_loadbarrier(access);
! }
! }
!
! return load_store;
}
Node* ZBarrierSetC2::atomic_xchg_at_resolved(C2AtomicParseAccess& access, Node* new_val, const Type* val_type) const {
Node* result = BarrierSetC2::atomic_xchg_at_resolved(access, new_val, val_type);
! if (!barrier_needed(access)) {
! return result;
}
!
! Node* load_store = access.raw_access();
! Node* adr = access.addr().node();
!
! assert(access.is_parse_access(), "entry not supported at optimization time");
! C2ParseAccess& parse_access = static_cast<C2ParseAccess&>(access);
! return load_barrier(parse_access.kit(), load_store, adr, false, false, false);
}
// == Macro Expansion ==
void ZBarrierSetC2::expand_loadbarrier_node(PhaseMacroExpand* phase, LoadBarrierNode* barrier) const {
- Node* in_ctrl = barrier->in(LoadBarrierNode::Control);
- Node* in_mem = barrier->in(LoadBarrierNode::Memory);
- Node* in_val = barrier->in(LoadBarrierNode::Oop);
- Node* in_adr = barrier->in(LoadBarrierNode::Address);
-
- Node* out_ctrl = barrier->proj_out(LoadBarrierNode::Control);
- Node* out_res = barrier->proj_out(LoadBarrierNode::Oop);
-
PhaseIterGVN &igvn = phase->igvn();
-
- if (ZVerifyLoadBarriers) {
- igvn.replace_node(out_res, in_val);
- igvn.replace_node(out_ctrl, in_ctrl);
- return;
- }
-
- if (barrier->can_be_eliminated()) {
- // Clone and pin the load for this barrier below the dominating
- // barrier: the load cannot be allowed to float above the
- // dominating barrier
- Node* load = in_val;
-
- if (load->is_Load()) {
- Node* new_load = load->clone();
- Node* addp = new_load->in(MemNode::Address);
- assert(addp->is_AddP() || addp->is_Phi() || addp->is_Load(), "bad address");
- Node* cast = new CastPPNode(addp, igvn.type(addp), true);
- Node* ctrl = NULL;
- Node* similar = barrier->in(LoadBarrierNode::Similar);
- if (similar->is_Phi()) {
- // already expanded
- ctrl = similar->in(0);
- } else {
- assert(similar->is_Proj() && similar->in(0)->is_LoadBarrier(), "unexpected graph shape");
- ctrl = similar->in(0)->as_LoadBarrier()->proj_out(LoadBarrierNode::Control);
- }
- assert(ctrl != NULL, "bad control");
- cast->set_req(0, ctrl);
- igvn.transform(cast);
- new_load->set_req(MemNode::Address, cast);
- igvn.transform(new_load);
-
- igvn.replace_node(out_res, new_load);
- igvn.replace_node(out_ctrl, in_ctrl);
- return;
- }
- // cannot eliminate
- }
-
- // There are two cases that require the basic loadbarrier
- // 1) When the writeback of a healed oop must be avoided (swap)
- // 2) When we must guarantee that no reload of is done (swap, cas, cmpx)
- if (!barrier->is_writeback()) {
- assert(!barrier->oop_reload_allowed(), "writeback barriers should be marked as requires oop");
- }
-
- if (!barrier->oop_reload_allowed()) {
- expand_loadbarrier_basic(phase, barrier);
- } else {
- expand_loadbarrier_optimized(phase, barrier);
- }
- }
-
- // Basic loadbarrier using conventional argument passing
- void ZBarrierSetC2::expand_loadbarrier_basic(PhaseMacroExpand* phase, LoadBarrierNode *barrier) const {
- PhaseIterGVN &igvn = phase->igvn();
-
- Node* in_ctrl = barrier->in(LoadBarrierNode::Control);
- Node* in_mem = barrier->in(LoadBarrierNode::Memory);
- Node* in_val = barrier->in(LoadBarrierNode::Oop);
- Node* in_adr = barrier->in(LoadBarrierNode::Address);
-
- Node* out_ctrl = barrier->proj_out(LoadBarrierNode::Control);
- Node* out_res = barrier->proj_out(LoadBarrierNode::Oop);
-
float unlikely = PROB_UNLIKELY(0.999);
- const Type* in_val_maybe_null_t = igvn.type(in_val);
-
- Node* jthread = igvn.transform(new ThreadLocalNode());
- Node* adr = phase->basic_plus_adr(jthread, in_bytes(ZThreadLocalData::address_bad_mask_offset()));
- Node* bad_mask = igvn.transform(LoadNode::make(igvn, in_ctrl, in_mem, adr, TypeRawPtr::BOTTOM, TypeX_X, TypeX_X->basic_type(), MemNode::unordered));
- Node* cast = igvn.transform(new CastP2XNode(in_ctrl, in_val));
- Node* obj_masked = igvn.transform(new AndXNode(cast, bad_mask));
- Node* cmp = igvn.transform(new CmpXNode(obj_masked, igvn.zerocon(TypeX_X->basic_type())));
- Node *bol = igvn.transform(new BoolNode(cmp, BoolTest::ne))->as_Bool();
- IfNode* iff = igvn.transform(new IfNode(in_ctrl, bol, unlikely, COUNT_UNKNOWN))->as_If();
- Node* then = igvn.transform(new IfTrueNode(iff));
- Node* elsen = igvn.transform(new IfFalseNode(iff));
-
- Node* result_region;
- Node* result_val;
-
- result_region = new RegionNode(3);
- result_val = new PhiNode(result_region, TypeInstPtr::BOTTOM);
-
- result_region->set_req(1, elsen);
- Node* res = igvn.transform(new CastPPNode(in_val, in_val_maybe_null_t));
- res->init_req(0, elsen);
- result_val->set_req(1, res);
-
- const TypeFunc *tf = load_barrier_Type();
- Node* call;
- if (barrier->is_weak()) {
- call = new CallLeafNode(tf,
- ZBarrierSetRuntime::load_barrier_on_weak_oop_field_preloaded_addr(),
- "ZBarrierSetRuntime::load_barrier_on_weak_oop_field_preloaded",
- TypeRawPtr::BOTTOM);
- } else {
- call = new CallLeafNode(tf,
- ZBarrierSetRuntime::load_barrier_on_oop_field_preloaded_addr(),
- "ZBarrierSetRuntime::load_barrier_on_oop_field_preloaded",
- TypeRawPtr::BOTTOM);
- }
-
- call->init_req(TypeFunc::Control, then);
- call->init_req(TypeFunc::I_O , phase->top());
- call->init_req(TypeFunc::Memory , in_mem);
- call->init_req(TypeFunc::FramePtr, phase->top());
- call->init_req(TypeFunc::ReturnAdr, phase->top());
- call->init_req(TypeFunc::Parms+0, in_val);
- if (barrier->is_writeback()) {
- call->init_req(TypeFunc::Parms+1, in_adr);
- } else {
- // When slow path is called with a null address, the healed oop will not be written back
- call->init_req(TypeFunc::Parms+1, igvn.zerocon(T_OBJECT));
- }
- call = igvn.transform(call);
-
- Node* ctrl = igvn.transform(new ProjNode(call, TypeFunc::Control));
- res = igvn.transform(new ProjNode(call, TypeFunc::Parms));
- res = igvn.transform(new CheckCastPPNode(ctrl, res, in_val_maybe_null_t));
-
- result_region->set_req(2, ctrl);
- result_val->set_req(2, res);
-
- result_region = igvn.transform(result_region);
- result_val = igvn.transform(result_val);
-
- if (out_ctrl != NULL) { // Added if cond
- igvn.replace_node(out_ctrl, result_region);
- }
- igvn.replace_node(out_res, result_val);
- }
-
- // Optimized, low spill, loadbarrier variant using stub specialized on register used
- void ZBarrierSetC2::expand_loadbarrier_optimized(PhaseMacroExpand* phase, LoadBarrierNode *barrier) const {
- PhaseIterGVN &igvn = phase->igvn();
- #ifdef PRINT_NODE_TRAVERSALS
- Node* preceding_barrier_node = barrier->in(LoadBarrierNode::Oop);
- #endif
Node* in_ctrl = barrier->in(LoadBarrierNode::Control);
Node* in_mem = barrier->in(LoadBarrierNode::Memory);
Node* in_val = barrier->in(LoadBarrierNode::Oop);
Node* in_adr = barrier->in(LoadBarrierNode::Address);
! Node* out_ctrl = barrier->proj_out(LoadBarrierNode::Control);
Node* out_res = barrier->proj_out(LoadBarrierNode::Oop);
assert(barrier->in(LoadBarrierNode::Oop) != NULL, "oop to loadbarrier node cannot be null");
- #ifdef PRINT_NODE_TRAVERSALS
- tty->print("\n\n\nBefore barrier optimization:\n");
- traverse(barrier, out_ctrl, out_res, -1);
-
- tty->print("\nBefore barrier optimization: preceding_barrier_node\n");
- traverse(preceding_barrier_node, out_ctrl, out_res, -1);
- #endif
-
- float unlikely = PROB_UNLIKELY(0.999);
-
Node* jthread = igvn.transform(new ThreadLocalNode());
Node* adr = phase->basic_plus_adr(jthread, in_bytes(ZThreadLocalData::address_bad_mask_offset()));
Node* bad_mask = igvn.transform(LoadNode::make(igvn, in_ctrl, in_mem, adr,
TypeRawPtr::BOTTOM, TypeX_X, TypeX_X->basic_type(),
MemNode::unordered));
--- 460,522 ----
if (!barrier_needed(access)) {
return p;
}
bool weak = (access.decorators() & ON_WEAK_OOP_REF) != 0;
assert(access.is_parse_access(), "entry not supported at optimization time");
! if (p->isa_Load()) {
! p->as_Load()->set_barrier(weak);
}
return p;
}
Node* ZBarrierSetC2::atomic_cmpxchg_val_at_resolved(C2AtomicParseAccess& access, Node* expected_val,
Node* new_val, const Type* val_type) const {
Node* result = BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, val_type);
! LoadStoreNode* lsn = result->as_LoadStore();
! if (barrier_needed(access)) {
! lsn->set_has_barrier();
}
! return lsn;
}
Node* ZBarrierSetC2::atomic_cmpxchg_bool_at_resolved(C2AtomicParseAccess& access, Node* expected_val,
Node* new_val, const Type* value_type) const {
Node* result = BarrierSetC2::atomic_cmpxchg_bool_at_resolved(access, expected_val, new_val, value_type);
! LoadStoreNode* lsn = result->as_LoadStore();
! if (barrier_needed(access)) {
! lsn->set_has_barrier();
}
! return lsn;
}
Node* ZBarrierSetC2::atomic_xchg_at_resolved(C2AtomicParseAccess& access, Node* new_val, const Type* val_type) const {
Node* result = BarrierSetC2::atomic_xchg_at_resolved(access, new_val, val_type);
! LoadStoreNode* lsn = result->as_LoadStore();
! if (barrier_needed(access)) {
! lsn->set_has_barrier();
}
! return lsn;
}
// == Macro Expansion ==
+ // Optimized, low spill, loadbarrier variant using stub specialized on register used
void ZBarrierSetC2::expand_loadbarrier_node(PhaseMacroExpand* phase, LoadBarrierNode* barrier) const {
PhaseIterGVN &igvn = phase->igvn();
float unlikely = PROB_UNLIKELY(0.999);
Node* in_ctrl = barrier->in(LoadBarrierNode::Control);
Node* in_mem = barrier->in(LoadBarrierNode::Memory);
Node* in_val = barrier->in(LoadBarrierNode::Oop);
Node* in_adr = barrier->in(LoadBarrierNode::Address);
! Node* out_ctrl = barrier->proj_out_or_null(LoadBarrierNode::Control);
Node* out_res = barrier->proj_out(LoadBarrierNode::Oop);
assert(barrier->in(LoadBarrierNode::Oop) != NULL, "oop to loadbarrier node cannot be null");
Node* jthread = igvn.transform(new ThreadLocalNode());
Node* adr = phase->basic_plus_adr(jthread, in_bytes(ZThreadLocalData::address_bad_mask_offset()));
Node* bad_mask = igvn.transform(LoadNode::make(igvn, in_ctrl, in_mem, adr,
TypeRawPtr::BOTTOM, TypeX_X, TypeX_X->basic_type(),
MemNode::unordered));
*** 966,1026 ****
Node *bol = igvn.transform(new BoolNode(cmp, BoolTest::ne))->as_Bool();
IfNode* iff = igvn.transform(new IfNode(in_ctrl, bol, unlikely, COUNT_UNKNOWN))->as_If();
Node* then = igvn.transform(new IfTrueNode(iff));
Node* elsen = igvn.transform(new IfFalseNode(iff));
! Node* slow_path_surrogate;
! if (!barrier->is_weak()) {
! slow_path_surrogate = igvn.transform(new LoadBarrierSlowRegNode(then, in_mem, in_adr, in_val->adr_type(),
! (const TypePtr*) in_val->bottom_type(), MemNode::unordered));
! } else {
! slow_path_surrogate = igvn.transform(new LoadBarrierWeakSlowRegNode(then, in_mem, in_adr, in_val->adr_type(),
! (const TypePtr*) in_val->bottom_type(), MemNode::unordered));
! }
- Node *new_loadp;
- new_loadp = slow_path_surrogate;
// Create the final region/phi pair to converge cntl/data paths to downstream code
Node* result_region = igvn.transform(new RegionNode(3));
result_region->set_req(1, then);
result_region->set_req(2, elsen);
Node* result_phi = igvn.transform(new PhiNode(result_region, TypeInstPtr::BOTTOM));
result_phi->set_req(1, new_loadp);
result_phi->set_req(2, barrier->in(LoadBarrierNode::Oop));
! // Finally, connect the original outputs to the barrier region and phi to complete the expansion/substitution
! // igvn.replace_node(out_ctrl, result_region);
! if (out_ctrl != NULL) { // added if cond
igvn.replace_node(out_ctrl, result_region);
}
igvn.replace_node(out_res, result_phi);
assert(barrier->outcnt() == 0,"LoadBarrier macro node has non-null outputs after expansion!");
! #ifdef PRINT_NODE_TRAVERSALS
! tty->print("\nAfter barrier optimization: old out_ctrl\n");
! traverse(out_ctrl, out_ctrl, out_res, -1);
! tty->print("\nAfter barrier optimization: old out_res\n");
! traverse(out_res, out_ctrl, out_res, -1);
! tty->print("\nAfter barrier optimization: old barrier\n");
! traverse(barrier, out_ctrl, out_res, -1);
! tty->print("\nAfter barrier optimization: preceding_barrier_node\n");
! traverse(preceding_barrier_node, result_region, result_phi, -1);
! #endif
assert(is_gc_barrier_node(result_phi), "sanity");
assert(step_over_gc_barrier(result_phi) == in_val, "sanity");
}
bool ZBarrierSetC2::expand_barriers(Compile* C, PhaseIterGVN& igvn) const {
ZBarrierSetC2State* s = state();
if (s->load_barrier_count() > 0) {
PhaseMacroExpand macro(igvn);
! #ifdef ASSERT
! verify_gc_barriers(false);
! #endif
int skipped = 0;
while (s->load_barrier_count() > skipped) {
int load_barrier_count = s->load_barrier_count();
LoadBarrierNode * n = s->load_barrier_node(load_barrier_count-1-skipped);
if (igvn.type(n) == Type::TOP || (n->in(0) != NULL && n->in(0)->is_top())) {
--- 526,569 ----
Node *bol = igvn.transform(new BoolNode(cmp, BoolTest::ne))->as_Bool();
IfNode* iff = igvn.transform(new IfNode(in_ctrl, bol, unlikely, COUNT_UNKNOWN))->as_If();
Node* then = igvn.transform(new IfTrueNode(iff));
Node* elsen = igvn.transform(new IfFalseNode(iff));
! Node* new_loadp = igvn.transform(new LoadBarrierSlowRegNode(then, in_mem, in_adr, in_val->adr_type(),
! (const TypePtr*) in_val->bottom_type(), MemNode::unordered, barrier->is_weak()));
// Create the final region/phi pair to converge cntl/data paths to downstream code
Node* result_region = igvn.transform(new RegionNode(3));
result_region->set_req(1, then);
result_region->set_req(2, elsen);
Node* result_phi = igvn.transform(new PhiNode(result_region, TypeInstPtr::BOTTOM));
result_phi->set_req(1, new_loadp);
result_phi->set_req(2, barrier->in(LoadBarrierNode::Oop));
! if (out_ctrl != NULL) {
igvn.replace_node(out_ctrl, result_region);
}
igvn.replace_node(out_res, result_phi);
assert(barrier->outcnt() == 0,"LoadBarrier macro node has non-null outputs after expansion!");
! igvn.remove_dead_node(barrier);
! igvn.remove_dead_node(out_ctrl);
! igvn.remove_dead_node(out_res);
assert(is_gc_barrier_node(result_phi), "sanity");
assert(step_over_gc_barrier(result_phi) == in_val, "sanity");
+
+ phase->C->print_method(PHASE_BARRIER_EXPANSION, 4, barrier->_idx);
}
bool ZBarrierSetC2::expand_barriers(Compile* C, PhaseIterGVN& igvn) const {
ZBarrierSetC2State* s = state();
if (s->load_barrier_count() > 0) {
PhaseMacroExpand macro(igvn);
!
int skipped = 0;
while (s->load_barrier_count() > skipped) {
int load_barrier_count = s->load_barrier_count();
LoadBarrierNode * n = s->load_barrier_node(load_barrier_count-1-skipped);
if (igvn.type(n) == Type::TOP || (n->in(0) != NULL && n->in(0)->is_top())) {
*** 1057,1435 ****
}
return false;
}
- // == Loop optimization ==
-
- static bool replace_with_dominating_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, bool last_round) {
- PhaseIterGVN &igvn = phase->igvn();
- Compile* C = Compile::current();
-
- LoadBarrierNode* lb2 = lb->has_dominating_barrier(phase, false, last_round);
- if (lb2 == NULL) {
- return false;
- }
-
- if (lb->in(LoadBarrierNode::Oop) != lb2->in(LoadBarrierNode::Oop)) {
- assert(lb->in(LoadBarrierNode::Address) == lb2->in(LoadBarrierNode::Address), "Invalid address");
- igvn.replace_input_of(lb, LoadBarrierNode::Similar, lb2->proj_out(LoadBarrierNode::Oop));
- C->set_major_progress();
- return false;
- }
-
- // That transformation may cause the Similar edge on dominated load barriers to be invalid
- lb->fix_similar_in_uses(&igvn);
-
- Node* val = lb->proj_out(LoadBarrierNode::Oop);
- assert(lb2->has_true_uses(), "Invalid uses");
- assert(lb2->in(LoadBarrierNode::Oop) == lb->in(LoadBarrierNode::Oop), "Invalid oop");
- phase->lazy_update(lb, lb->in(LoadBarrierNode::Control));
- phase->lazy_replace(lb->proj_out(LoadBarrierNode::Control), lb->in(LoadBarrierNode::Control));
- igvn.replace_node(val, lb2->proj_out(LoadBarrierNode::Oop));
-
- return true;
- }
-
- static Node* find_dominating_memory(PhaseIdealLoop* phase, Node* mem, Node* dom, int i) {
- assert(dom->is_Region() || i == -1, "");
-
- Node* m = mem;
- while(phase->is_dominator(dom, phase->has_ctrl(m) ? phase->get_ctrl(m) : m->in(0))) {
- if (m->is_Mem()) {
- assert(m->as_Mem()->adr_type() == TypeRawPtr::BOTTOM, "");
- m = m->in(MemNode::Memory);
- } else if (m->is_MergeMem()) {
- m = m->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
- } else if (m->is_Phi()) {
- if (m->in(0) == dom && i != -1) {
- m = m->in(i);
- break;
- } else {
- m = m->in(LoopNode::EntryControl);
- }
- } else if (m->is_Proj()) {
- m = m->in(0);
- } else if (m->is_SafePoint() || m->is_MemBar()) {
- m = m->in(TypeFunc::Memory);
- } else {
- #ifdef ASSERT
- m->dump();
- #endif
- ShouldNotReachHere();
- }
- }
-
- return m;
- }
-
- static LoadBarrierNode* clone_load_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, Node* ctl, Node* mem, Node* oop_in) {
- PhaseIterGVN &igvn = phase->igvn();
- Compile* C = Compile::current();
- Node* the_clone = lb->clone();
- the_clone->set_req(LoadBarrierNode::Control, ctl);
- the_clone->set_req(LoadBarrierNode::Memory, mem);
- if (oop_in != NULL) {
- the_clone->set_req(LoadBarrierNode::Oop, oop_in);
- }
-
- LoadBarrierNode* new_lb = the_clone->as_LoadBarrier();
- igvn.register_new_node_with_optimizer(new_lb);
- IdealLoopTree *loop = phase->get_loop(new_lb->in(0));
- phase->set_ctrl(new_lb, new_lb->in(0));
- phase->set_loop(new_lb, loop);
- phase->set_idom(new_lb, new_lb->in(0), phase->dom_depth(new_lb->in(0))+1);
- if (!loop->_child) {
- loop->_body.push(new_lb);
- }
-
- Node* proj_ctl = new ProjNode(new_lb, LoadBarrierNode::Control);
- igvn.register_new_node_with_optimizer(proj_ctl);
- phase->set_ctrl(proj_ctl, proj_ctl->in(0));
- phase->set_loop(proj_ctl, loop);
- phase->set_idom(proj_ctl, new_lb, phase->dom_depth(new_lb)+1);
- if (!loop->_child) {
- loop->_body.push(proj_ctl);
- }
-
- Node* proj_oop = new ProjNode(new_lb, LoadBarrierNode::Oop);
- phase->register_new_node(proj_oop, new_lb);
-
- if (!new_lb->in(LoadBarrierNode::Similar)->is_top()) {
- LoadBarrierNode* similar = new_lb->in(LoadBarrierNode::Similar)->in(0)->as_LoadBarrier();
- if (!phase->is_dominator(similar, ctl)) {
- igvn.replace_input_of(new_lb, LoadBarrierNode::Similar, C->top());
- }
- }
-
- return new_lb;
- }
-
- static void replace_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, Node* new_val) {
- PhaseIterGVN &igvn = phase->igvn();
- Node* val = lb->proj_out(LoadBarrierNode::Oop);
- igvn.replace_node(val, new_val);
- phase->lazy_update(lb, lb->in(LoadBarrierNode::Control));
- phase->lazy_replace(lb->proj_out(LoadBarrierNode::Control), lb->in(LoadBarrierNode::Control));
- }
-
- static bool split_barrier_thru_phi(PhaseIdealLoop* phase, LoadBarrierNode* lb) {
- PhaseIterGVN &igvn = phase->igvn();
- Compile* C = Compile::current();
-
- if (lb->in(LoadBarrierNode::Oop)->is_Phi()) {
- Node* oop_phi = lb->in(LoadBarrierNode::Oop);
-
- if ((oop_phi->req() != 3) || (oop_phi->in(2) == oop_phi)) {
- // Ignore phis with only one input
- return false;
- }
-
- if (phase->is_dominator(phase->get_ctrl(lb->in(LoadBarrierNode::Address)),
- oop_phi->in(0)) && phase->get_ctrl(lb->in(LoadBarrierNode::Address)) != oop_phi->in(0)) {
- // That transformation may cause the Similar edge on dominated load barriers to be invalid
- lb->fix_similar_in_uses(&igvn);
-
- RegionNode* region = oop_phi->in(0)->as_Region();
-
- int backedge = LoopNode::LoopBackControl;
- if (region->is_Loop() && region->in(backedge)->is_Proj() && region->in(backedge)->in(0)->is_If()) {
- Node* c = region->in(backedge)->in(0)->in(0);
- assert(c->unique_ctrl_out() == region->in(backedge)->in(0), "");
- Node* oop = lb->in(LoadBarrierNode::Oop)->in(backedge);
- Node* oop_c = phase->has_ctrl(oop) ? phase->get_ctrl(oop) : oop;
- if (!phase->is_dominator(oop_c, c)) {
- return false;
- }
- }
-
- // If the node on the backedge above the phi is the node itself - we have a self loop.
- // Don't clone - this will be folded later.
- if (oop_phi->in(LoopNode::LoopBackControl) == lb->proj_out(LoadBarrierNode::Oop)) {
- return false;
- }
-
- bool is_strip_mined = region->is_CountedLoop() && region->as_CountedLoop()->is_strip_mined();
- Node *phi = oop_phi->clone();
-
- for (uint i = 1; i < region->req(); i++) {
- Node* ctrl = region->in(i);
- if (ctrl != C->top()) {
- assert(!phase->is_dominator(ctrl, region) || region->is_Loop(), "");
-
- Node* mem = lb->in(LoadBarrierNode::Memory);
- Node* m = find_dominating_memory(phase, mem, region, i);
-
- if (region->is_Loop() && i == LoopNode::LoopBackControl && ctrl->is_Proj() && ctrl->in(0)->is_If()) {
- ctrl = ctrl->in(0)->in(0);
- } else if (region->is_Loop() && is_strip_mined) {
- // If this is a strip mined loop, control must move above OuterStripMinedLoop
- assert(i == LoopNode::EntryControl, "check");
- assert(ctrl->is_OuterStripMinedLoop(), "sanity");
- ctrl = ctrl->as_OuterStripMinedLoop()->in(LoopNode::EntryControl);
- }
-
- LoadBarrierNode* new_lb = clone_load_barrier(phase, lb, ctrl, m, lb->in(LoadBarrierNode::Oop)->in(i));
- Node* out_ctrl = new_lb->proj_out(LoadBarrierNode::Control);
-
- if (is_strip_mined && (i == LoopNode::EntryControl)) {
- assert(region->in(i)->is_OuterStripMinedLoop(), "");
- igvn.replace_input_of(region->in(i), i, out_ctrl);
- phase->set_idom(region->in(i), out_ctrl, phase->dom_depth(out_ctrl));
- } else if (ctrl == region->in(i)) {
- igvn.replace_input_of(region, i, out_ctrl);
- // Only update the idom if is the loop entry we are updating
- // - A loop backedge doesn't change the idom
- if (region->is_Loop() && i == LoopNode::EntryControl) {
- phase->set_idom(region, out_ctrl, phase->dom_depth(out_ctrl));
- }
- } else {
- Node* iff = region->in(i)->in(0);
- igvn.replace_input_of(iff, 0, out_ctrl);
- phase->set_idom(iff, out_ctrl, phase->dom_depth(out_ctrl)+1);
- }
- phi->set_req(i, new_lb->proj_out(LoadBarrierNode::Oop));
- }
- }
- phase->register_new_node(phi, region);
- replace_barrier(phase, lb, phi);
-
- if (region->is_Loop()) {
- // Load barrier moved to the back edge of the Loop may now
- // have a safepoint on the path to the barrier on the Similar
- // edge
- igvn.replace_input_of(phi->in(LoopNode::LoopBackControl)->in(0), LoadBarrierNode::Similar, C->top());
- Node* head = region->in(LoopNode::EntryControl);
- phase->set_idom(region, head, phase->dom_depth(head)+1);
- phase->recompute_dom_depth();
- if (head->is_CountedLoop() && head->as_CountedLoop()->is_main_loop()) {
- head->as_CountedLoop()->set_normal_loop();
- }
- }
-
- return true;
- }
- }
-
- return false;
- }
-
- static bool move_out_of_loop(PhaseIdealLoop* phase, LoadBarrierNode* lb) {
- PhaseIterGVN &igvn = phase->igvn();
- IdealLoopTree *lb_loop = phase->get_loop(lb->in(0));
- if (lb_loop != phase->ltree_root() && !lb_loop->_irreducible) {
- Node* oop_ctrl = phase->get_ctrl(lb->in(LoadBarrierNode::Oop));
- IdealLoopTree *oop_loop = phase->get_loop(oop_ctrl);
- IdealLoopTree* adr_loop = phase->get_loop(phase->get_ctrl(lb->in(LoadBarrierNode::Address)));
- if (!lb_loop->is_member(oop_loop) && !lb_loop->is_member(adr_loop)) {
- // That transformation may cause the Similar edge on dominated load barriers to be invalid
- lb->fix_similar_in_uses(&igvn);
-
- Node* head = lb_loop->_head;
- assert(head->is_Loop(), "");
-
- if (phase->is_dominator(head, oop_ctrl)) {
- assert(oop_ctrl->Opcode() == Op_CProj && oop_ctrl->in(0)->Opcode() == Op_NeverBranch, "");
- assert(lb_loop->is_member(phase->get_loop(oop_ctrl->in(0)->in(0))), "");
- return false;
- }
-
- if (head->is_CountedLoop()) {
- CountedLoopNode* cloop = head->as_CountedLoop();
- if (cloop->is_main_loop()) {
- cloop->set_normal_loop();
- }
- // When we are moving barrier out of a counted loop,
- // make sure we move it all the way out of the strip mined outer loop.
- if (cloop->is_strip_mined()) {
- head = cloop->outer_loop();
- }
- }
-
- Node* mem = lb->in(LoadBarrierNode::Memory);
- Node* m = find_dominating_memory(phase, mem, head, -1);
-
- LoadBarrierNode* new_lb = clone_load_barrier(phase, lb, head->in(LoopNode::EntryControl), m, NULL);
-
- assert(phase->idom(head) == head->in(LoopNode::EntryControl), "");
- Node* proj_ctl = new_lb->proj_out(LoadBarrierNode::Control);
- igvn.replace_input_of(head, LoopNode::EntryControl, proj_ctl);
- phase->set_idom(head, proj_ctl, phase->dom_depth(proj_ctl) + 1);
-
- replace_barrier(phase, lb, new_lb->proj_out(LoadBarrierNode::Oop));
-
- phase->recompute_dom_depth();
-
- return true;
- }
- }
-
- return false;
- }
-
- static bool common_barriers(PhaseIdealLoop* phase, LoadBarrierNode* lb) {
- PhaseIterGVN &igvn = phase->igvn();
- Node* in_val = lb->in(LoadBarrierNode::Oop);
- for (DUIterator_Fast imax, i = in_val->fast_outs(imax); i < imax; i++) {
- Node* u = in_val->fast_out(i);
- if (u != lb && u->is_LoadBarrier() && u->as_LoadBarrier()->has_true_uses()) {
- Node* this_ctrl = lb->in(LoadBarrierNode::Control);
- Node* other_ctrl = u->in(LoadBarrierNode::Control);
-
- Node* lca = phase->dom_lca(this_ctrl, other_ctrl);
- bool ok = true;
-
- Node* proj1 = NULL;
- Node* proj2 = NULL;
-
- while (this_ctrl != lca && ok) {
- if (this_ctrl->in(0) != NULL &&
- this_ctrl->in(0)->is_MultiBranch()) {
- if (this_ctrl->in(0)->in(0) == lca) {
- assert(proj1 == NULL, "");
- assert(this_ctrl->is_Proj(), "");
- proj1 = this_ctrl;
- } else if (!(this_ctrl->in(0)->is_If() && this_ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none))) {
- ok = false;
- }
- }
- this_ctrl = phase->idom(this_ctrl);
- }
- while (other_ctrl != lca && ok) {
- if (other_ctrl->in(0) != NULL &&
- other_ctrl->in(0)->is_MultiBranch()) {
- if (other_ctrl->in(0)->in(0) == lca) {
- assert(other_ctrl->is_Proj(), "");
- assert(proj2 == NULL, "");
- proj2 = other_ctrl;
- } else if (!(other_ctrl->in(0)->is_If() && other_ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none))) {
- ok = false;
- }
- }
- other_ctrl = phase->idom(other_ctrl);
- }
- assert(proj1 == NULL || proj2 == NULL || proj1->in(0) == proj2->in(0), "");
- if (ok && proj1 && proj2 && proj1 != proj2 && proj1->in(0)->is_If()) {
- // That transformation may cause the Similar edge on dominated load barriers to be invalid
- lb->fix_similar_in_uses(&igvn);
- u->as_LoadBarrier()->fix_similar_in_uses(&igvn);
-
- Node* split = lca->unique_ctrl_out();
- assert(split->in(0) == lca, "");
-
- Node* mem = lb->in(LoadBarrierNode::Memory);
- Node* m = find_dominating_memory(phase, mem, split, -1);
- LoadBarrierNode* new_lb = clone_load_barrier(phase, lb, lca, m, NULL);
-
- Node* proj_ctl = new_lb->proj_out(LoadBarrierNode::Control);
- igvn.replace_input_of(split, 0, new_lb->proj_out(LoadBarrierNode::Control));
- phase->set_idom(split, proj_ctl, phase->dom_depth(proj_ctl)+1);
-
- Node* proj_oop = new_lb->proj_out(LoadBarrierNode::Oop);
- replace_barrier(phase, lb, proj_oop);
- replace_barrier(phase, u->as_LoadBarrier(), proj_oop);
-
- phase->recompute_dom_depth();
-
- return true;
- }
- }
- }
-
- return false;
- }
-
- void ZBarrierSetC2::loop_optimize_gc_barrier(PhaseIdealLoop* phase, Node* node, bool last_round) {
- if (!Compile::current()->directive()->ZOptimizeLoadBarriersOption) {
- return;
- }
-
- if (!node->is_LoadBarrier()) {
- return;
- }
-
- if (!node->as_LoadBarrier()->has_true_uses()) {
- return;
- }
-
- if (replace_with_dominating_barrier(phase, node->as_LoadBarrier(), last_round)) {
- return;
- }
-
- if (split_barrier_thru_phi(phase, node->as_LoadBarrier())) {
- return;
- }
-
- if (move_out_of_loop(phase, node->as_LoadBarrier())) {
- return;
- }
-
- if (common_barriers(phase, node->as_LoadBarrier())) {
- return;
- }
- }
-
Node* ZBarrierSetC2::step_over_gc_barrier(Node* c) const {
Node* node = c;
// 1. This step follows potential oop projections of a load barrier before expansion
if (node->is_Proj()) {
--- 600,609 ----
*** 1443,1453 ****
// 3. This step checks for the phi corresponding to an optimized load barrier expansion
if (node->is_Phi()) {
PhiNode* phi = node->as_Phi();
Node* n = phi->in(1);
! if (n != NULL && (n->is_LoadBarrierSlowReg() || n->is_LoadBarrierWeakSlowReg())) {
assert(c == node, "projections from step 1 should only be seen before macro expansion");
return phi->in(2);
}
}
--- 617,627 ----
// 3. This step checks for the phi corresponding to an optimized load barrier expansion
if (node->is_Phi()) {
PhiNode* phi = node->as_Phi();
Node* n = phi->in(1);
! if (n != NULL && n->is_LoadBarrierSlowReg()) {
assert(c == node, "projections from step 1 should only be seen before macro expansion");
return phi->in(2);
}
}
*** 1457,1495 ****
bool ZBarrierSetC2::array_copy_requires_gc_barriers(bool tightly_coupled_alloc, BasicType type, bool is_clone, ArrayCopyPhase phase) const {
return type == T_OBJECT || type == T_ARRAY;
}
bool ZBarrierSetC2::final_graph_reshaping(Compile* compile, Node* n, uint opcode) const {
! if (opcode != Op_LoadBarrierSlowReg &&
! opcode != Op_LoadBarrierWeakSlowReg) {
! return false;
! }
!
#ifdef ASSERT
if (VerifyOptoOopOffsets) {
! MemNode* mem = n->as_Mem();
// Check to see if address types have grounded out somehow.
! const TypeInstPtr* tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
! ciInstanceKlass* k = tp->klass()->as_instance_klass();
bool oop_offset_is_sane = k->contains_field_offset(tp->offset());
assert(!tp || oop_offset_is_sane, "");
}
#endif
-
return true;
}
bool ZBarrierSetC2::matcher_find_shared_visit(Matcher* matcher, Matcher::MStack& mstack, Node* n, uint opcode, bool& mem_op, int& mem_addr_idx) const {
! if (opcode == Op_CallLeaf &&
! (n->as_Call()->entry_point() == ZBarrierSetRuntime::load_barrier_on_oop_field_preloaded_addr() ||
! n->as_Call()->entry_point() == ZBarrierSetRuntime::load_barrier_on_weak_oop_field_preloaded_addr())) {
mem_op = true;
mem_addr_idx = TypeFunc::Parms + 1;
return true;
}
return false;
}
// == Verification ==
#ifdef ASSERT
--- 631,710 ----
bool ZBarrierSetC2::array_copy_requires_gc_barriers(bool tightly_coupled_alloc, BasicType type, bool is_clone, ArrayCopyPhase phase) const {
return type == T_OBJECT || type == T_ARRAY;
}
bool ZBarrierSetC2::final_graph_reshaping(Compile* compile, Node* n, uint opcode) const {
! switch (opcode) {
! case Op_LoadBarrier:
! assert(0, "There should be no load barriers left");
! case Op_ZGetAndSetP:
! case Op_ZCompareAndExchangeP:
! case Op_ZCompareAndSwapP:
! case Op_ZWeakCompareAndSwapP:
! case Op_LoadBarrierSlowReg:
#ifdef ASSERT
if (VerifyOptoOopOffsets) {
! MemNode *mem = n->as_Mem();
// Check to see if address types have grounded out somehow.
! const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
! ciInstanceKlass *k = tp->klass()->as_instance_klass();
bool oop_offset_is_sane = k->contains_field_offset(tp->offset());
assert(!tp || oop_offset_is_sane, "");
}
#endif
return true;
+ default:
+ return false;
+ }
}
bool ZBarrierSetC2::matcher_find_shared_visit(Matcher* matcher, Matcher::MStack& mstack, Node* n, uint opcode, bool& mem_op, int& mem_addr_idx) const {
! switch(opcode) {
! case Op_CallLeaf:
! if (n->as_Call()->entry_point() == ZBarrierSetRuntime::load_barrier_on_oop_field_preloaded_addr() ||
! n->as_Call()->entry_point() == ZBarrierSetRuntime::load_barrier_on_weak_oop_field_preloaded_addr()) {
mem_op = true;
mem_addr_idx = TypeFunc::Parms + 1;
return true;
}
+ return false;
+ default:
+ return false;
+ }
+ }
+
+ bool ZBarrierSetC2::matcher_find_shared_post_visit(Matcher* matcher, Node* n, uint opcode) const {
+ switch(opcode) {
+ case Op_ZCompareAndExchangeP:
+ case Op_ZCompareAndSwapP:
+ case Op_ZWeakCompareAndSwapP: {
+ Node *mem = n->in(MemNode::Address);
+ Node *keepalive = n->in(5);
+ Node *pair1 = new BinaryNode(mem, keepalive);
+
+ Node *newval = n->in(MemNode::ValueIn);
+ Node *oldval = n->in(LoadStoreConditionalNode::ExpectedIn);
+ Node *pair2 = new BinaryNode(oldval, newval);
+
+ n->set_req(MemNode::Address, pair1);
+ n->set_req(MemNode::ValueIn, pair2);
+ n->del_req(5);
+ n->del_req(LoadStoreConditionalNode::ExpectedIn);
+ return true;
+ }
+ case Op_ZGetAndSetP: {
+ Node *keepalive = n->in(4);
+ Node *newval = n->in(MemNode::ValueIn);
+ Node *pair = new BinaryNode(newval, keepalive);
+ n->set_req(MemNode::ValueIn, pair);
+ n->del_req(4);
+ return true;
+ }
+ default:
return false;
+ }
}
// == Verification ==
#ifdef ASSERT
*** 1518,1537 ****
return true;
}
void ZBarrierSetC2::verify_gc_barriers(Compile* compile, CompilePhase phase) const {
! if (phase == BarrierSetC2::BeforeCodeGen) return;
! bool post_parse = phase == BarrierSetC2::BeforeOptimize;
! verify_gc_barriers(post_parse);
}
void ZBarrierSetC2::verify_gc_barriers(bool post_parse) const {
ZBarrierSetC2State* s = state();
Compile* C = Compile::current();
ResourceMark rm;
VectorSet visited(Thread::current()->resource_area());
for (int i = 0; i < s->load_barrier_count(); i++) {
LoadBarrierNode* n = s->load_barrier_node(i);
// The dominating barrier on the same address if it exists and
// this barrier must not be applied on the value from the same
--- 733,768 ----
return true;
}
void ZBarrierSetC2::verify_gc_barriers(Compile* compile, CompilePhase phase) const {
! switch(phase) {
! case BarrierSetC2::BeforeOptimize:
! case BarrierSetC2::BeforeLateInsertion:
! assert(state()->load_barrier_count() == 0, "No barriers inserted yet");
! break;
! case BarrierSetC2::BeforeMacroExpand:
! // Barrier placement should be set by now.
! verify_gc_barriers(false /*post_parse*/);
! break;
! case BarrierSetC2::BeforeCodeGen:
! // Barriers has been fully expanded.
! assert(state()->load_barrier_count() == 0, "No more macro barriers");
! break;
! default:
! assert(0, "Phase without verification");
! }
}
+ // post_parse implies that there might be loadbarrers without uses after parsing
+ // That only applies when adding barriers at parse time.
void ZBarrierSetC2::verify_gc_barriers(bool post_parse) const {
ZBarrierSetC2State* s = state();
Compile* C = Compile::current();
ResourceMark rm;
VectorSet visited(Thread::current()->resource_area());
+
for (int i = 0; i < s->load_barrier_count(); i++) {
LoadBarrierNode* n = s->load_barrier_node(i);
// The dominating barrier on the same address if it exists and
// this barrier must not be applied on the value from the same
*** 1541,1551 ****
(n->in(LoadBarrierNode::Similar)->in(0)->is_LoadBarrier() &&
n->in(LoadBarrierNode::Similar)->in(0)->in(LoadBarrierNode::Address) == n->in(LoadBarrierNode::Address) &&
n->in(LoadBarrierNode::Similar)->in(0)->in(LoadBarrierNode::Oop) != n->in(LoadBarrierNode::Oop)),
"broken similar edge");
! assert(post_parse || n->as_LoadBarrier()->has_true_uses(),
"found unneeded load barrier");
// Several load barrier nodes chained through their Similar edge
// break the code that remove the barriers in final graph reshape.
assert(n->in(LoadBarrierNode::Similar)->is_top() ||
--- 772,782 ----
(n->in(LoadBarrierNode::Similar)->in(0)->is_LoadBarrier() &&
n->in(LoadBarrierNode::Similar)->in(0)->in(LoadBarrierNode::Address) == n->in(LoadBarrierNode::Address) &&
n->in(LoadBarrierNode::Similar)->in(0)->in(LoadBarrierNode::Oop) != n->in(LoadBarrierNode::Oop)),
"broken similar edge");
! assert(n->as_LoadBarrier()->has_true_uses(),
"found unneeded load barrier");
// Several load barrier nodes chained through their Similar edge
// break the code that remove the barriers in final graph reshape.
assert(n->in(LoadBarrierNode::Similar)->is_top() ||
*** 1556,1644 ****
if (!n->in(LoadBarrierNode::Similar)->is_top()) {
ResourceMark rm;
Unique_Node_List wq;
Node* other = n->in(LoadBarrierNode::Similar)->in(0);
wq.push(n);
- bool ok = true;
- bool dom_found = false;
for (uint next = 0; next < wq.size(); ++next) {
! Node *n = wq.at(next);
! assert(n->is_CFG(), "");
! assert(!n->is_SafePoint(), "");
! if (n == other) {
continue;
}
! if (n->is_Region()) {
! for (uint i = 1; i < n->req(); i++) {
! Node* m = n->in(i);
if (m != NULL) {
wq.push(m);
}
}
} else {
! Node* m = n->in(0);
if (m != NULL) {
wq.push(m);
}
}
}
}
! if (ZVerifyLoadBarriers) {
! if ((n->is_Load() || n->is_LoadStore()) && n->bottom_type()->make_oopptr() != NULL) {
! visited.Clear();
! bool found = look_for_barrier(n, post_parse, visited);
! if (!found) {
! n->dump(1);
! n->dump(-3);
! stringStream ss;
! C->method()->print_short_name(&ss);
! tty->print_cr("-%s-", ss.as_string());
! assert(found, "");
}
}
}
}
}
! #endif
! bool ZBarrierSetC2::escape_add_to_con_graph(ConnectionGraph* conn_graph, PhaseGVN* gvn, Unique_Node_List* delayed_worklist, Node* n, uint opcode) const {
! switch (opcode) {
! case Op_LoadBarrierSlowReg:
! case Op_LoadBarrierWeakSlowReg:
! conn_graph->add_objload_to_connection_graph(n, delayed_worklist);
! return true;
! case Op_Proj:
! if (n->as_Proj()->_con != LoadBarrierNode::Oop || !n->in(0)->is_LoadBarrier()) {
! return false;
}
- conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0)->in(LoadBarrierNode::Oop), delayed_worklist);
- return true;
}
! return false;
}
! bool ZBarrierSetC2::escape_add_final_edges(ConnectionGraph* conn_graph, PhaseGVN* gvn, Node* n, uint opcode) const {
! switch (opcode) {
! case Op_LoadBarrierSlowReg:
! case Op_LoadBarrierWeakSlowReg:
! if (gvn->type(n)->make_ptr() == NULL) {
return false;
}
! conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(MemNode::Address), NULL);
! return true;
! case Op_Proj:
! if (n->as_Proj()->_con != LoadBarrierNode::Oop || !n->in(0)->is_LoadBarrier()) {
! return false;
}
! conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0)->in(LoadBarrierNode::Oop), NULL);
! return true;
}
return false;
}
--- 787,1576 ----
if (!n->in(LoadBarrierNode::Similar)->is_top()) {
ResourceMark rm;
Unique_Node_List wq;
Node* other = n->in(LoadBarrierNode::Similar)->in(0);
wq.push(n);
for (uint next = 0; next < wq.size(); ++next) {
! Node *nn = wq.at(next);
! assert(nn->is_CFG(), "");
! assert(!nn->is_SafePoint(), "");
! if (nn == other) {
continue;
}
! if (nn->is_Region()) {
! for (uint i = 1; i < nn->req(); i++) {
! Node* m = nn->in(i);
if (m != NULL) {
wq.push(m);
}
}
} else {
! Node* m = nn->in(0);
if (m != NULL) {
wq.push(m);
}
}
}
}
+ }
+ }
+
+ #endif // end verification code
+
+ // This code is cloning all uses of a load that is between a call and the catch blocks,
+ // to each use.
+
+ static int fixup_uses_in_catch(PhaseIdealLoop *phase, Node *start_ctrl, Node *node) {
+
+ if (!phase->has_ctrl(node)) {
+ // This node is floating - doesn't need to be cloned.
+ assert(node != start_ctrl, "check");
+ return 0; // Unwind - 0 successors
+ }
+
+ Node* ctrl = phase->get_ctrl(node);
+ if (ctrl != start_ctrl) {
+ // We are in a successor block - the node is ok.
+ return 0; // Unwind - 0 successors
+ }
+
+ // Process successor nodes
+ int outcnt = node->outcnt();
+ for (int i = 0; i < outcnt; i++) {
+ Node* n = node->raw_out(0);
+ assert(!n->is_LoadBarrier(), "Sanity");
+ // Calling recursively, visiting leafs first
+ fixup_uses_in_catch(phase, start_ctrl, n);
+ }
+
+ // Now all successors are outside
+ // - Clone this node to both successors
+ int no_succs = node->outcnt();
+ for (DUIterator_Fast jmax, i = node->fast_outs(jmax); i < jmax; i++) {
+ Node* use = node->fast_out(i);
+ Node* clone = node->clone();
+ assert(clone->outcnt() == 0, "");
+
+ assert(use->find_edge(node) != -1, "check");
+ phase->igvn().rehash_node_delayed(use);
+ use->replace_edge(node, clone);
+
+ Node* new_ctrl;
+ if (use->is_block_start()) {
+ new_ctrl = use;
+ } else if (use->is_CFG()) {
+ new_ctrl = use->in(0);
+ assert (new_ctrl != NULL, "");
+ } else {
+ new_ctrl = phase->get_ctrl(use);
+ }
+
+ phase->set_ctrl(clone, new_ctrl);
+
+ if (phase->C->directive()->ZTraceLoadBarriersOption) tty->print_cr(" Clone op %i as %i to control %i", node->_idx, clone->_idx, new_ctrl->_idx);
+ phase->igvn().register_new_node_with_optimizer(clone);
+ --i, --jmax;
+ }
+ assert(node->outcnt() == 0, "must be empty now");
+
+ // Node node is dead.
+ phase->igvn().remove_dead_node(node);
+
+ return no_succs; // unwind - returning number of nodes that were cloned
+ }
+
+ // Clone a load to a specific catch_proj
+ static Node* clone_load_to_catchproj(PhaseIdealLoop* phase, Node* load, Node* catch_proj) {
+ Node* cloned_load = load->clone();
+ cloned_load->set_req(0, catch_proj); // set explicit control
+ phase->set_ctrl(cloned_load, catch_proj); // update
+ if (phase->C->directive()->ZTraceLoadBarriersOption) tty->print_cr(" Clone LOAD %i as %i to control %i", load->_idx, cloned_load->_idx, catch_proj->_idx);
+ phase->igvn().register_new_node_with_optimizer(cloned_load);
+ return cloned_load;
+ }
+
+ static Node* get_dominating_region(PhaseIdealLoop* phase, Node* node, Node* stop) {
+ Node* region = node;
+ while (!region->isa_Region()) {
+ Node *up = phase->idom(region);
+ assert(up != region, "Must not loop");
+ assert(up != stop, "Must not find original control");
+ region = up;
+ }
+ return region;
+ }
+
+ // Clone this load to each catch block
+ static void call_catch_cleanup_one(PhaseIdealLoop* phase, LoadNode* load, Node* ctrl) {
+ bool trace = phase->C->directive()->ZTraceLoadBarriersOption;
+ phase->igvn().set_delay_transform(true);
+
+ // Verify pre conditions
+ assert(ctrl->isa_Proj() && ctrl->in(0)->isa_Call(), "Must be a call proj");
+ assert(ctrl->raw_out(0)->isa_Catch(), "Must be a catch");
+
+ if (ctrl->raw_out(0)->isa_Catch()->outcnt() == 1) {
+ if (trace) tty->print_cr("Cleaning up catch: Skipping load %i, call with single catch", load->_idx);
+ return;
+ }
+
+ // Process the loads successor nodes - if any is between
+ // the call and the catch blocks, they need to be cloned to.
+ // This is done recursively
+ int outcnt = load->outcnt();
+ int index = 0;
+ for (int i = 0; i < outcnt; i++) {
+ Node* n = load->raw_out(index);
+ assert(!n->is_LoadBarrier(), "Sanity");
+ int removed = fixup_uses_in_catch(phase, ctrl, n);
+ if (removed == 0 ) { // if no successor was cloned, progress to next out.
+ index++;
+ }
+ }
+
+ // Now all the loads uses has been cloned down
+ // Only thing left is to clone the loads, but they must end up
+ // first in the catch blocks.
+
+ // We clone the loads oo the catch blocks only when needed.
+ // An array is used to map the catch blocks to each lazily cloned load.
+ // In that way no extra unnecessary loads are cloned.
+
+ // Any use dominated by original block must have an phi and a region added
+
+ Node* catch_node = ctrl->raw_out(0);
+ int number_of_catch_projs = catch_node->outcnt();
+ Node** proj_to_load_mapping = NEW_RESOURCE_ARRAY(Node*, number_of_catch_projs);
+ Copy::zero_to_bytes(proj_to_load_mapping, sizeof(Node*) * number_of_catch_projs);
+
+ for (unsigned int i = 0; i < load->outcnt(); i++) {
+ Node* load_use_control = NULL;
+ Node* load_use = load->raw_out(i);
+
+ if (phase->has_ctrl(load_use)) {
+ load_use_control = phase->get_ctrl(load_use);
+ } else {
+ load_use_control = load_use->in(0);
+ }
+ assert(load_use_control != NULL, "sanity");
+ if (trace) tty->print_cr(" Handling use: %i, with control: %i", load_use->_idx, load_use_control->_idx);
! // Some times the loads use is a phi. For them we need to determine from which catch block
! // the use is defined.
! bool load_use_is_phi = false;
! unsigned int load_use_phi_index = 0;
! Node* phi_ctrl = NULL;
! if (load_use->is_Phi()) {
! // Find phi input that matches load
! for (unsigned int u = 1; u < load_use->req(); u++) {
! if (load_use->in(u) == load) {
! load_use_is_phi = true;
! load_use_phi_index = u;
! assert(load_use->in(0)->is_Region(), "Region or broken");
! phi_ctrl = load_use->in(0)->in(u);
! assert(phi_ctrl->is_CFG(), "check");
! assert(phi_ctrl != load, "check");
! break;
}
}
+ assert(load_use_is_phi, "must find");
+ assert(load_use_phi_index > 0, "sanity");
}
+
+ // For each load use, see witch catch projs dominates, create load clone lazily and reconnect
+ bool found_dominating_catchproj = false;
+ for (int c = 0; c < number_of_catch_projs; c++) {
+ Node* catchproj = catch_node->raw_out(c);
+ assert(catchproj != NULL && catchproj->isa_CatchProj(), "Sanity");
+
+ if (!phase->is_dominator(catchproj, load_use_control)) {
+ if (load_use_is_phi && phase->is_dominator(catchproj, phi_ctrl)) {
+ // The loads use is local to the catchproj.
+ // fall out and replace load with catch-local load clone.
+ } else {
+ continue;
+ }
+ }
+ assert(!found_dominating_catchproj, "Max one should match");
+
+ // Clone loads to catch projs
+ Node* load_clone = proj_to_load_mapping[c];
+ if (load_clone == NULL) {
+ load_clone = clone_load_to_catchproj(phase, load, catchproj);
+ proj_to_load_mapping[c] = load_clone;
+ }
+ phase->igvn().rehash_node_delayed(load_use);
+
+ if (load_use_is_phi) {
+ // phis are special - the load is defined from a specific control flow
+ load_use->set_req(load_use_phi_index, load_clone);
+ } else {
+ // Multipe edges can be replaced at once - on calls for example
+ load_use->replace_edge(load, load_clone);
+ }
+ --i; // more than one edge can have been removed, but the next is in later iterations
+
+ // We could break the for-loop after finding a dominating match.
+ // But keep iterating to catch any bad idom early.
+ found_dominating_catchproj = true;
+ }
+
+ // We found no single catchproj that dominated the use - The use is at a point after
+ // where control flow from multiple catch projs have merged. We will have to create
+ // phi nodes before the use and tie the output from the cloned loads together. It
+ // can be a single phi or a number of chained phis, depending on control flow
+ if (!found_dominating_catchproj) {
+
+ // Use phi-control if use is a phi
+ if (load_use_is_phi) {
+ load_use_control = phi_ctrl;
+ }
+ assert(phase->is_dominator(ctrl, load_use_control), "Common use but no dominator");
+
+ // Clone a load on all paths
+ for (int c = 0; c < number_of_catch_projs; c++) {
+ Node* catchproj = catch_node->raw_out(c);
+ Node* load_clone = proj_to_load_mapping[c];
+ if (load_clone == NULL) {
+ load_clone = clone_load_to_catchproj(phase, load, catchproj);
+ proj_to_load_mapping[c] = load_clone;
+ }
+ }
+
+ // Move up dominator tree from use until dom front is reached
+ Node* next_region = get_dominating_region(phase, load_use_control, ctrl);
+ while (phase->idom(next_region) != catch_node) {
+ next_region = phase->idom(next_region);
+ }
+ assert(phase->is_dominator(catch_node, next_region), "Sanity");
+
+ // Create a phi node that will collect all cloned loads and feed it to the use.
+ PhiNode* next_phi = new PhiNode(next_region, load->type());
+ phase->igvn().rehash_node_delayed(load_use);
+ load_use->replace_edge(load, next_phi);
+
+ int dominators_of_region = 0;
+ do {
+ // New phi, connect to region and add all loads as in.
+ Node* region = next_region;
+ assert(region->isa_Region() && region->req() > 2, "Catch dead region nodes");
+ PhiNode* new_phi = next_phi;
+
+ if (trace) tty->print_cr("Created Phi %i on load %i with control %i", new_phi->_idx, load->_idx, region->_idx);
+
+ // Need to add all cloned loads to the phi, taking care that the right path is matched
+ dominators_of_region = 0; // reset for new region
+ for (unsigned int reg_i = 1; reg_i < region->req(); reg_i++) {
+ Node* region_pred = region->in(reg_i);
+ assert(region_pred->is_CFG(), "check");
+ bool pred_has_dominator = false;
+ for (int c = 0; c < number_of_catch_projs; c++) {
+ Node* catchproj = catch_node->raw_out(c);
+ if (phase->is_dominator(catchproj, region_pred)) {
+ new_phi->set_req(reg_i, proj_to_load_mapping[c]);
+ if (trace) tty->print_cr(" - Phi in(%i) set to load %i", reg_i, proj_to_load_mapping[c]->_idx);
+ pred_has_dominator = true;
+ dominators_of_region++;
+ break;
+ }
+ }
+
+ // Sometimes we need to chain several phis.
+ if (!pred_has_dominator) {
+ assert(dominators_of_region <= 1, "More than one region can't require extra phi");
+ if (trace) tty->print_cr(" - Region %i pred %i not dominated by catch proj", region->_idx, region_pred->_idx);
+ // Continue search on on this region_pred
+ // - walk up to next region
+ // - create a new phi and connect to first new_phi
+ next_region = get_dominating_region(phase, region_pred, ctrl);
+ next_phi = new PhiNode(next_region, load->type());
+ new_phi->set_req(reg_i, next_phi);
+ }
+ }
+
+ new_phi->set_req(0, region);
+ phase->igvn().register_new_node_with_optimizer(new_phi);
+ phase->set_ctrl(new_phi, region);
+
+ assert(dominators_of_region != 0, "Must have found one this iteration");
+ } while (dominators_of_region == 1);
+
+ --i;
}
+ } // end of loop over uses
+
+ assert(load->outcnt() == 0, "All uses should be handled");
+ phase->igvn().remove_dead_node(load);
+ phase->C->print_method(PHASE_CALL_CATCH_CLEANUP, 4, load->_idx);
+
+ // Now we should be home
+ phase->igvn().set_delay_transform(false);
}
! // Sort out the loads that are between a call ant its catch blocks
! static void process_catch_cleanup_candidate(PhaseIdealLoop* phase, LoadNode* load) {
! bool trace = phase->C->directive()->ZTraceLoadBarriersOption;
! Node* ctrl = phase->get_ctrl(load);
! if (!ctrl->is_Proj() || (ctrl->in(0) == NULL) || !ctrl->in(0)->isa_Call()) {
! return;
! }
! Node* catch_node = ctrl->isa_Proj()->raw_out(0);
! if (catch_node->is_Catch()) {
! if (catch_node->outcnt() > 1) {
! call_catch_cleanup_one(phase, load, ctrl);
! } else {
! if (trace) tty->print_cr("Call catch cleanup with only one catch: load %i ", load->_idx);
}
}
+ }
! void ZBarrierSetC2::barrier_insertion_phase(PhaseIterGVN& igvn) const {
! PhaseIdealLoop ideal_loop(igvn, LoopOptsBarrierInsertion);
! igvn.C->clear_major_progress();
}
! void ZBarrierSetC2::barrier_insertion(PhaseIdealLoop* phase) const {
! // First make sure all loads between call and catch are moved to the catch block
! clean_catch_blocks(phase);
!
! // Then expand barriers on all loads
! insert_load_barriers(phase);
!
! // Handle all Unsafe that need barriers.
! insert_barriers_on_unsafe(phase);
! }
!
! static bool can_simplify_cas(LoadStoreNode* node) {
! if (node->isa_LoadStoreConditional()) {
! Node *expected_in = node->as_LoadStoreConditional()->in(LoadStoreConditionalNode::ExpectedIn);
! return (expected_in->get_ptr_type() == TypePtr::NULL_PTR);
! } else {
return false;
}
! }
! static void insert_barrier_before_unsafe(PhaseIdealLoop* phase, LoadStoreNode* old_node) {
!
! Compile *C = phase->C;
! PhaseIterGVN &igvn = phase->igvn();
! LoadStoreNode* zclone = NULL;
! bool is_weak = false;
!
! Node *in_ctrl = old_node->in(MemNode::Control);
! Node *in_mem = old_node->in(MemNode::Memory);
! Node *in_adr = old_node->in(MemNode::Address);
! Node *in_val = old_node->in(MemNode::ValueIn);
! const TypePtr *adr_type = old_node->adr_type();
! const TypePtr* load_type = TypeOopPtr::BOTTOM; // The type for the load we are adding
!
! switch (old_node->Opcode()) {
! case Op_CompareAndExchangeP: {
! zclone = new ZCompareAndExchangePNode(in_ctrl, in_mem, in_adr, in_val, old_node->in(LoadStoreConditionalNode::ExpectedIn),
! adr_type, old_node->get_ptr_type(), ((CompareAndExchangeNode*)old_node)->order());
! load_type = old_node->bottom_type()->is_ptr();
! break;
! }
! case Op_WeakCompareAndSwapP: {
! if (can_simplify_cas(old_node)) {
! break;
! }
! is_weak = true;
! zclone = new ZWeakCompareAndSwapPNode(in_ctrl, in_mem, in_adr, in_val, old_node->in(LoadStoreConditionalNode::ExpectedIn),
! ((CompareAndSwapNode*)old_node)->order());
! adr_type = TypePtr::BOTTOM;
! break;
! }
! case Op_CompareAndSwapP: {
! if (can_simplify_cas(old_node)) {
! break;
! }
! zclone = new ZCompareAndSwapPNode(in_ctrl, in_mem, in_adr, in_val, old_node->in(LoadStoreConditionalNode::ExpectedIn),
! ((CompareAndSwapNode*)old_node)->order());
! adr_type = TypePtr::BOTTOM;
! break;
! }
! case Op_GetAndSetP: {
! zclone = new ZGetAndSetPNode(in_ctrl, in_mem, in_adr, in_val, old_node->adr_type(), old_node->get_ptr_type());
! load_type = old_node->bottom_type()->is_ptr();
! break;
! }
! }
! if (zclone != NULL) {
! igvn.register_new_node_with_optimizer(zclone, old_node);
!
! // Make load
! LoadPNode *load = new LoadPNode(NULL, in_mem, in_adr, adr_type, load_type, MemNode::unordered,
! LoadNode::DependsOnlyOnTest);
! load->set_barrier_expanded();
! igvn.register_new_node_with_optimizer(load);
! igvn.replace_node(old_node, zclone);
!
! Node *barrier = new LoadBarrierNode(C, NULL, in_mem, load, in_adr, is_weak);
! Node *barrier_val = new ProjNode(barrier, LoadBarrierNode::Oop);
! Node *barrier_ctrl = new ProjNode(barrier, LoadBarrierNode::Control);
!
! igvn.register_new_node_with_optimizer(barrier);
! igvn.register_new_node_with_optimizer(barrier_val);
! igvn.register_new_node_with_optimizer(barrier_ctrl);
!
! // loop over all of in_ctrl usages and move to barrier_ctrl
! for (DUIterator_Last imin, i = in_ctrl->last_outs(imin); i >= imin; --i) {
! Node *use = in_ctrl->last_out(i);
! uint l;
! for (l = 0; use->in(l) != in_ctrl; l++) {}
! igvn.replace_input_of(use, l, barrier_ctrl);
! }
!
! load->set_req(MemNode::Control, in_ctrl);
! barrier->set_req(LoadBarrierNode::Control, in_ctrl);
! zclone->add_req(barrier_val); // add req as keep alive.
!
! C->print_method(PHASE_ADD_UNSAFE_BARRIER, 4, zclone->_idx);
! }
! }
!
! void ZBarrierSetC2::insert_barriers_on_unsafe(PhaseIdealLoop* phase) const {
! Compile *C = phase->C;
! PhaseIterGVN &igvn = phase->igvn();
! uint new_ids = C->unique();
! VectorSet visited(Thread::current()->resource_area());
! GrowableArray<Node *> nodeStack(Thread::current()->resource_area(), 0, 0, NULL);
! nodeStack.push(C->root());
! visited.test_set(C->root()->_idx);
!
! // Traverse all nodes, visit all unsafe ops that require a barrier
! while (nodeStack.length() > 0) {
! Node *n = nodeStack.pop();
!
! bool is_old_node = (n->_idx < new_ids); // don't process nodes that were created during cleanup
! if (is_old_node) {
! if (n->is_LoadStore()) {
! LoadStoreNode* lsn = n->as_LoadStore();
! if (lsn->has_barrier()) {
! BasicType bt = lsn->in(MemNode::Address)->bottom_type()->basic_type();
! assert ((bt == T_OBJECT || bt == T_ARRAY), "Sanity test");
! insert_barrier_before_unsafe(phase, lsn);
! }
! }
! }
! for (uint i = 0; i < n->len(); i++) {
! if (n->in(i)) {
! if (!visited.test_set(n->in(i)->_idx)) {
! nodeStack.push(n->in(i));
! }
! }
! }
! }
!
! igvn.optimize();
! C->print_method(PHASE_ADD_UNSAFE_BARRIER, 2);
! }
!
! // The purpose of ZBarrierSetC2::clean_catch_blocks is to prepare the IR for
! // splicing in load barrier nodes.
! //
! // The problem is that we might have instructions between a call and its catch nodes.
! // (This is usually handled in PhaseCFG:call_catch_cleanup, which clones mach nodes in
! // already scheduled blocks.) We can't have loads that require barriers there,
! // because we need to splice in new control flow, and that would violate the IR.
! //
! // clean_catch_blocks find all Loads that require a barrier and clone them and any
! // dependent instructions to each use. The loads must be in the beginning of the catch block
! // before any store.
! //
! // Sometimes the loads use will be at a place dominated by all catch blocks, then we need
! // a load in each catch block, and a Phi at the dominated use.
!
! void ZBarrierSetC2::clean_catch_blocks(PhaseIdealLoop* phase) const {
!
! Compile *C = phase->C;
! uint new_ids = C->unique();
! PhaseIterGVN &igvn = phase->igvn();
! VectorSet visited(Thread::current()->resource_area());
! GrowableArray<Node *> nodeStack(Thread::current()->resource_area(), 0, 0, NULL);
! nodeStack.push(C->root());
! visited.test_set(C->root()->_idx);
!
! // Traverse all nodes, visit all loads that require a barrier
! while(nodeStack.length() > 0) {
! Node *n = nodeStack.pop();
!
! bool is_old_node = (n->_idx < new_ids); // don't process nodes that were created during cleanup
! if (n->is_Load() && is_old_node) {
! LoadNode* load = n->isa_Load();
! // only care about loads that will have a barrier
! if (load->is_barrier_required()) {
! process_catch_cleanup_candidate(phase, load);
! }
! }
!
! for (uint i = 0; i < n->len(); i++) {
! if (n->in(i)) {
! if (!visited.test_set(n->in(i)->_idx)) {
! nodeStack.push(n->in(i));
! }
! }
! }
! }
!
! C->print_method(PHASE_CALL_CATCH_CLEANUP, 2);
! }
!
! class DomDepthCompareClosure : public CompareClosure<LoadNode*> {
! PhaseIdealLoop* _phase;
!
! public:
! DomDepthCompareClosure(PhaseIdealLoop* phase) : _phase(phase) { }
!
! int do_compare(LoadNode* const &n1, LoadNode* const &n2) {
! int d1 = _phase->dom_depth(_phase->get_ctrl(n1));
! int d2 = _phase->dom_depth(_phase->get_ctrl(n2));
! if (d1 == d2) {
! // Compare index if the depth is the same, ensures all entries are unique.
! return n1->_idx - n2->_idx;
! } else {
! return d2 - d1;
! }
! }
! };
!
! // Traverse graph and add all loadPs to list, sorted by dom depth
! void gather_loadnodes_sorted(PhaseIdealLoop* phase, GrowableArray<LoadNode*>* loadList) {
!
! VectorSet visited(Thread::current()->resource_area());
! GrowableArray<Node *> nodeStack(Thread::current()->resource_area(), 0, 0, NULL);
! DomDepthCompareClosure ddcc(phase);
!
! nodeStack.push(phase->C->root());
! while(nodeStack.length() > 0) {
! Node *n = nodeStack.pop();
! if (visited.test(n->_idx)) {
! continue;
! }
!
! if (n->isa_Load()) {
! LoadNode *load = n->as_Load();
! if (load->is_barrier_required()) {
! assert(phase->get_ctrl(load) != NULL, "sanity");
! assert(phase->dom_depth(phase->get_ctrl(load)) != 0, "sanity");
! loadList->insert_sorted(&ddcc, load);
! }
! }
!
! visited.set(n->_idx);
! for (uint i = 0; i < n->req(); i++) {
! if (n->in(i)) {
! if (!visited.test(n->in(i)->_idx)) {
! nodeStack.push(n->in(i));
! }
! }
}
! }
! }
!
! // Add LoadBarriers to all LoadPs
! void ZBarrierSetC2::insert_load_barriers(PhaseIdealLoop* phase) const {
!
! bool trace = phase->C->directive()->ZTraceLoadBarriersOption;
! GrowableArray<LoadNode *> loadList(Thread::current()->resource_area(), 0, 0, NULL);
! gather_loadnodes_sorted(phase, &loadList);
!
! PhaseIterGVN &igvn = phase->igvn();
! int count = 0;
!
! for (GrowableArrayIterator<LoadNode *> loadIter = loadList.begin(); loadIter != loadList.end(); ++loadIter) {
! LoadNode *load = *loadIter;
!
! if (load->is_barrier_expanded()) {
! continue;
! }
!
! do {
! // Insert a barrier on a loadP
! // if another load is found that needs to be expanded first, retry on that one
! LoadNode* result = insert_one_loadbarrier(phase, load, phase->get_ctrl(load));
! while (result != NULL) {
! result = insert_one_loadbarrier(phase, result, phase->get_ctrl(result));
! }
! } while (!load->is_barrier_expanded());
! }
!
! phase->C->print_method(PHASE_INSERT_BARRIER, 2);
! }
!
! void push_antidependent_stores(PhaseIdealLoop* phase, Node_Stack& nodestack, LoadNode* start_load) {
! // push all stores on the same mem, that can_alias
! // Any load found must be handled first
! PhaseIterGVN &igvn = phase->igvn();
! int load_alias_idx = igvn.C->get_alias_index(start_load->adr_type());
!
! Node *mem = start_load->in(1);
! for (DUIterator_Fast imax, u = mem->fast_outs(imax); u < imax; u++) {
! Node *mem_use = mem->fast_out(u);
!
! if (mem_use == start_load) continue;
! if (!mem_use->is_Store()) continue;
! if (!phase->has_ctrl(mem_use)) continue;
! if (phase->get_ctrl(mem_use) != phase->get_ctrl(start_load)) continue;
!
! // add any aliasing store in this block
! StoreNode *store = mem_use->isa_Store();
! const TypePtr *adr_type = store->adr_type();
! if (igvn.C->can_alias(adr_type, load_alias_idx)) {
! nodestack.push(store, 0);
! }
! }
! }
!
! LoadNode* ZBarrierSetC2::insert_one_loadbarrier(PhaseIdealLoop* phase, LoadNode* start_load, Node* ctrl) const {
! bool trace = phase->C->directive()->ZTraceLoadBarriersOption;
! PhaseIterGVN &igvn = phase->igvn();
!
! // Check for other loadPs at the same loop depth that is reachable by a DFS
! // - if found - return it. It needs to be inserted first
! // - otherwise proceed and insert barrier
!
! VectorSet visited(Thread::current()->resource_area());
! Node_Stack nodestack(100);
!
! nodestack.push(start_load, 0);
! push_antidependent_stores(phase, nodestack, start_load);
!
! while(!nodestack.is_empty()) {
! Node* n = nodestack.node(); // peek
! nodestack.pop();
! if (visited.test(n->_idx)) {
! continue;
! }
!
! if (n->is_Load() && n != start_load && n->as_Load()->is_barrier_required() && !n->as_Load()->is_barrier_expanded()) {
! // Found another load that needs a barrier in the same block. Must expand later loads first.
! if (trace) tty->print_cr(" * Found LoadP %i on DFS", n->_idx);
! return n->as_Load(); // return node that should be expanded first
}
+ if (!phase->has_ctrl(n)) continue;
+ if (phase->get_ctrl(n) != phase->get_ctrl(start_load)) continue;
+ if (n->is_Phi()) continue;
+
+ visited.set(n->_idx);
+ // push all children
+ for (DUIterator_Fast imax, ii = n->fast_outs(imax); ii < imax; ii++) {
+ Node* c = n->fast_out(ii);
+ if (c != NULL) {
+ nodestack.push(c, 0);
+ }
+ }
+ }
+
+ insert_one_loadbarrier_inner(phase, start_load, ctrl, visited);
+ return NULL;
+ }
+
+ void ZBarrierSetC2::insert_one_loadbarrier_inner(PhaseIdealLoop* phase, LoadNode* load, Node* ctrl, VectorSet visited2) const {
+ PhaseIterGVN &igvn = phase->igvn();
+ Compile* C = igvn.C;
+ bool trace = C->directive()->ZTraceLoadBarriersOption;
+
+ // create barrier
+ Node* barrier = new LoadBarrierNode(C, NULL, load->in(LoadNode::Memory), NULL, load->in(LoadNode::Address), load->is_barrier_weak());
+ Node* barrier_val = new ProjNode(barrier, LoadBarrierNode::Oop);
+ Node* barrier_ctrl = new ProjNode(barrier, LoadBarrierNode::Control);
+
+ if (trace) tty->print_cr("Insert load %i with barrier: %i and ctrl : %i", load->_idx, barrier->_idx, ctrl->_idx);
+
+ // Splice control
+ // - insert barrier control diamond between loads ctrl and ctrl successor on path to block end.
+ // - If control successor is a catch, step over to next.
+ Node* ctrl_succ = NULL;
+ for (DUIterator_Fast imax, j = ctrl->fast_outs(imax); j < imax; j++) {
+ Node* tmp = ctrl->fast_out(j);
+
+ // - CFG nodes is the ones we are going to splice (1 only!)
+ // - Phi nodes will continue to hang from the region node!
+ // - self loops should be skipped
+ if (tmp->is_Phi() || tmp == ctrl) {
+ continue;
+ }
+
+ if (tmp->is_CFG()) {
+ assert(ctrl_succ == NULL, "There can be only one");
+ ctrl_succ = tmp;
+ continue;
+ }
+ }
+
+ // Now splice control
+ assert(ctrl_succ != load, "sanity");
+ assert(ctrl_succ != NULL, "Broken IR");
+ bool found = false;
+ for(uint k = 0; k < ctrl_succ->req(); k++) {
+ if (ctrl_succ->in(k) == ctrl) {
+ assert(!found, "sanity");
+ if (trace) tty->print_cr(" Move CFG ctrl_succ %i to barrier_ctrl", ctrl_succ->_idx);
+ igvn.replace_input_of(ctrl_succ, k, barrier_ctrl);
+ found = true;
+ k--;
+ }
+ }
+
+ // For all successors of ctrl - move all visited to become successors of barrier_ctrl instead
+ for (DUIterator_Fast imax, r = ctrl->fast_outs(imax); r < imax; r++) {
+ Node* tmp = ctrl->fast_out(r);
+ if (visited2.test(tmp->_idx) && (tmp != load)) {
+ if (trace) tty->print_cr(" Move ctrl_succ %i to barrier_ctrl", tmp->_idx);
+ igvn.replace_input_of(tmp, 0, barrier_ctrl);
+ --r; --imax;
+ }
+ }
+
+ // Move the loads user to the barrier
+ for (DUIterator_Fast imax, i = load->fast_outs(imax); i < imax; i++) {
+ Node* u = load->fast_out(i);
+ if (u->isa_LoadBarrier()) {
+ continue;
+ }
+
+ // find correct input - replace with iterator?
+ for(uint j = 0; j < u->req(); j++) {
+ if (u->in(j) == load) {
+ igvn.replace_input_of(u, j, barrier_val);
+ --i; --imax; // Adjust the iterator of the *outer* loop
+ break; // some nodes (calls) might have several uses from the same node
+ }
+ }
+ }
+
+ // Connect barrier to load and control
+ barrier->set_req(LoadBarrierNode::Oop, load);
+ barrier->set_req(LoadBarrierNode::Control, ctrl);
+
+ igvn.rehash_node_delayed(load);
+ igvn.register_new_node_with_optimizer(barrier);
+ igvn.register_new_node_with_optimizer(barrier_val);
+ igvn.register_new_node_with_optimizer(barrier_ctrl);
+ load->set_barrier_expanded();
+
+ C->print_method(PHASE_INSERT_BARRIER, 3, load->_idx);
+ }
+
+ // The bad_mask in the ThreadLocalData shouldn't have an anti-dep-check.
+ // The bad_mask address if of type TypeRawPtr, but that will alias
+ // InitializeNodes until the type system is expanded.
+ bool ZBarrierSetC2::needs_anti_dependence_check(const Node* node) const {
+ MachNode* mnode = node->as_Mach();
+ if (mnode != NULL) {
+ intptr_t offset = 0;
+ const TypePtr *adr_type2 = NULL;
+ const Node* base = mnode->get_base_and_disp(offset, adr_type2);
+ if ((base != NULL) &&
+ (base->is_Mach() && base->as_Mach()->ideal_Opcode() == Op_ThreadLocal) &&
+ (offset == in_bytes(ZThreadLocalData::address_bad_mask_offset()))) {
return false;
+ }
+ }
+ return true;
}
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