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#ifdef COMPILER1
#include "c1/c1_LIRAssembler.hpp"
#include "c1/c1_MacroAssembler.hpp"
#include "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp"
#endif
+ #ifdef COMPILER2
+ #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
+ #endif
#define __ masm->
static void save_machine_state(MacroAssembler* masm, bool handle_gpr, bool handle_fp) {
if (handle_gpr) {
//
// Before reaching to resolve sequence, see if we can avoid the whole shebang
// with filters.
// Filter: when offending in-memory value is null, the failure is definitely legitimate
- __ testptr(oldval, oldval);
+ if (UseCompressedOops) {
+ __ testl(oldval, oldval);
+ } else {
+ __ testptr(oldval, oldval);
+ }
__ jcc(Assembler::zero, L_failure);
// Filter: when heap is stable, the failure is definitely legitimate
const Register thread = r15_thread;
Address gc_state(thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
__ movptr(res, 1);
__ bind(exit);
}
}
+ #ifdef COMPILER2
+ void ShenandoahBarrierSetAssembler::load_ref_barrier_c2(const MachNode* node, MacroAssembler* masm, Register obj, Register addr, Register tmp1, Register tmp2, Register tmp3, bool narrow) {
+ if (!ShenandoahLoadRefBarrierStubC2::needs_barrier(node)) {
+ return;
+ }
+ Assembler::InlineSkippedInstructionsCounter skip_counter(masm);
+
+ ShenandoahLoadRefBarrierStubC2* const stub = ShenandoahLoadRefBarrierStubC2::create(node, obj, addr, tmp1, tmp2, tmp3, narrow);
+ stub->dont_preserve(obj); // set at the end, no need to save
+ if (tmp1 != noreg) {
+ stub->dont_preserve(tmp1); // temp, no need to save
+ }
+ if (tmp2 != noreg) {
+ stub->dont_preserve(tmp2); // temp, no need to save
+ }
+ if (tmp3 != noreg) {
+ stub->dont_preserve(tmp3); // temp, no need to save
+ }
+
+ Address gc_state(r15_thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
+ int flags = ShenandoahHeap::HAS_FORWARDED;
+ bool is_strong = (node->barrier_data() & ShenandoahBarrierStrong) != 0;
+ if (!is_strong) {
+ flags |= ShenandoahHeap::WEAK_ROOTS;
+ }
+ __ testb(gc_state, flags);
+ __ jcc(Assembler::notZero, *stub->entry());
+ __ bind(*stub->continuation());
+ }
+
+ void ShenandoahBarrierSetAssembler::satb_barrier_c2(const MachNode* node, MacroAssembler* masm,
+ Register addr, Register preval, Register tmp) {
+ if (!ShenandoahSATBBarrierStubC2::needs_barrier(node)) {
+ return;
+ }
+ ShenandoahSATBBarrierStubC2* const stub = ShenandoahSATBBarrierStubC2::create(node, addr, preval, tmp);
+ Assembler::InlineSkippedInstructionsCounter skip_counter(masm);
+ Address gc_state(r15_thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
+ __ testb(gc_state, ShenandoahHeap::MARKING);
+ __ jcc(Assembler::notZero, *stub->entry());
+ __ bind(*stub->continuation());
+ }
+
+ void ShenandoahBarrierSetAssembler::card_barrier_c2(const MachNode* node, MacroAssembler* masm,
+ Register addr, Register addr_tmp, Register tmp) {
+ if (!ShenandoahCardBarrier ||
+ (node->barrier_data() & (ShenandoahBarrierCardMark | ShenandoahBarrierCardMarkNotNull)) == 0) {
+ return;
+ }
+ Assembler::InlineSkippedInstructionsCounter skip_counter(masm);
+ if (addr != noreg) {
+ __ mov(addr_tmp, addr);
+ }
+ __ shrptr(addr_tmp, CardTable::card_shift());
+
+ Address curr_ct_holder_addr(r15_thread, in_bytes(ShenandoahThreadLocalData::card_table_offset()));
+ __ movptr(tmp, curr_ct_holder_addr);
+ Address card_addr(tmp, addr_tmp, Address::times_1);
+
+ int dirty = CardTable::dirty_card_val();
+ if (UseCondCardMark) {
+ Label L_already_dirty;
+ __ cmpb(card_addr, dirty);
+ __ jccb(Assembler::equal, L_already_dirty);
+ __ movb(card_addr, dirty);
+ __ bind(L_already_dirty);
+ } else {
+ __ movb(card_addr, dirty);
+ }
+ }
+
+ void ShenandoahBarrierSetAssembler::cmpxchg_oop_c2(const MachNode* node, MacroAssembler* masm,
+ Register res, Address addr, Register oldval, Register newval, Register tmp1, Register tmp2,
+ bool exchange) {
+ assert(oldval == rax, "must be in rax for implicit use in cmpxchg");
+ assert_different_registers(oldval, tmp1, tmp2);
+ assert_different_registers(newval, tmp1, tmp2);
+
+ // Remember oldval for retry logic in slow path. We need to do it here,
+ // because it will be overwritten by the fast-path CAS.
+ if (ShenandoahCASBarrier) {
+ __ movptr(tmp2, oldval);
+ }
+
+ // Fast-path: Try to CAS optimistically. If successful, then we are done.
+ __ lock();
+ if (UseCompressedOops) {
+ __ cmpxchgl(newval, addr);
+ } else {
+ __ cmpxchgptr(newval, addr);
+ }
+
+ // If we need a boolean result out of CAS, set the flag appropriately and promote the result.
+ // This would be the final result if we do not go slow.
+ if (!exchange) {
+ assert(res != noreg, "need result register");
+ __ setcc(Assembler::equal, res);
+ } else {
+ assert(res == noreg, "no result expected");
+ }
+
+ if (ShenandoahCASBarrier) {
+ ShenandoahCASBarrierSlowStubC2* const slow_stub =
+ ShenandoahCASBarrierSlowStubC2::create(node, addr, oldval, newval, res, tmp1, tmp2, exchange);
+ if (res != noreg) {
+ slow_stub->dont_preserve(res); // set at the end, no need to save
+ }
+ slow_stub->dont_preserve(oldval); // saved explicitly
+ slow_stub->dont_preserve(tmp1); // temp, no need to save
+ slow_stub->dont_preserve(tmp2); // temp, no need to save
+
+ // On success, we do not need any additional handling.
+ __ jccb(Assembler::equal, *slow_stub->continuation());
+
+ // If GC is in progress, it is likely we need additional handling for false negatives.
+ Address gc_state(r15_thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
+ __ testb(gc_state, ShenandoahHeap::HAS_FORWARDED);
+ __ jcc(Assembler::notZero, *slow_stub->entry());
+
+ // Slow stub re-enters with result set correctly.
+ __ bind(*slow_stub->continuation());
+ }
+ }
+
+ #undef __
+ #define __ masm.
+
+ void ShenandoahLoadRefBarrierStubC2::emit_code(MacroAssembler& masm) {
+ Assembler::InlineSkippedInstructionsCounter skip_counter(&masm);
+ __ bind(*entry());
+
+ Register obj = _obj;
+ if (_narrow) {
+ __ movl(_tmp1, _obj);
+ __ decode_heap_oop(_tmp1);
+ obj = _tmp1;
+ }
+
+ // Weak/phantom loads always need to go to runtime.
+ if ((_node->barrier_data() & ShenandoahBarrierStrong) != 0) {
+ __ movptr(_tmp2, obj);
+ __ shrptr(_tmp2, ShenandoahHeapRegion::region_size_bytes_shift_jint());
+ __ movptr(_tmp3, (intptr_t) ShenandoahHeap::in_cset_fast_test_addr());
+ __ movbool(_tmp2, Address(_tmp2, _tmp3, Address::times_1));
+ __ testbool(_tmp2);
+ __ jcc(Assembler::zero, *continuation());
+ }
+
+ {
+ SaveLiveRegisters save_registers(&masm, this);
+ if (c_rarg0 != obj) {
+ if (c_rarg0 == _addr) {
+ __ movptr(_tmp2, _addr);
+ _addr = _tmp2;
+ }
+ __ movptr(c_rarg0, obj);
+ }
+ if (c_rarg1 != _addr) {
+ __ movptr(c_rarg1, _addr);
+ }
+
+ address entry;
+ if (_narrow) {
+ if ((_node->barrier_data() & ShenandoahBarrierStrong) != 0) {
+ entry = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow);
+ } else if ((_node->barrier_data() & ShenandoahBarrierWeak) != 0) {
+ entry = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak_narrow);
+ } else if ((_node->barrier_data() & ShenandoahBarrierPhantom) != 0) {
+ entry = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom_narrow);
+ }
+ } else {
+ if ((_node->barrier_data() & ShenandoahBarrierStrong) != 0) {
+ entry = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong);
+ } else if ((_node->barrier_data() & ShenandoahBarrierWeak) != 0) {
+ entry = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak);
+ } else if ((_node->barrier_data() & ShenandoahBarrierPhantom) != 0) {
+ entry = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom);
+ }
+ }
+ __ call(RuntimeAddress(entry), rax);
+ assert(!save_registers.contains(_obj), "must not save result register");
+ __ movptr(_obj, rax);
+ }
+ if (_narrow) {
+ __ encode_heap_oop(_obj);
+ }
+
+ __ jmp(*continuation());
+ }
+
+ void ShenandoahSATBBarrierStubC2::emit_code(MacroAssembler& masm) {
+ __ bind(*entry());
+ Address index(r15_thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()));
+ Address buffer(r15_thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()));
+
+ Label runtime;
+
+ // Do we need to load the previous value?
+ if (_addr != noreg) {
+ __ load_heap_oop(_preval, Address(_addr, 0), noreg, AS_RAW);
+ }
+ // Is the previous value null?
+ __ cmpptr(_preval, NULL_WORD);
+ __ jcc(Assembler::equal, *continuation());
+
+ // Can we store a value in the given thread's buffer?
+ // (The index field is typed as size_t.)
+ __ movptr(_tmp, index);
+ __ testptr(_tmp, _tmp);
+ __ jccb(Assembler::zero, runtime);
+ // The buffer is not full, store value into it.
+ __ subptr(_tmp, wordSize);
+ __ movptr(index, _tmp);
+ __ addptr(_tmp, buffer);
+ __ movptr(Address(_tmp, 0), _preval);
+
+ __ jmp(*continuation());
+
+ __ bind(runtime);
+ {
+ SaveLiveRegisters save_registers(&masm, this);
+ if (c_rarg0 != _preval) {
+ __ mov(c_rarg0, _preval);
+ }
+ // rax is a caller-saved, non-argument-passing register, so it does not
+ // interfere with c_rarg0 or c_rarg1. If it contained any live value before
+ // entering this stub, it is saved at this point, and restored after the
+ // call. If it did not contain any live value, it is free to be used. In
+ // either case, it is safe to use it here as a call scratch register.
+ __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_barrier_pre_c2)), rax);
+ }
+ __ jmp(*continuation());
+ }
+
+ void ShenandoahCASBarrierMidStubC2::emit_code(MacroAssembler& masm) {
+ // x86_64 does not implement this.
+ ShouldNotReachHere();
+ }
+
+ void ShenandoahCASBarrierSlowStubC2::emit_code(MacroAssembler& masm) {
+ __ bind(*entry());
+
+ // CAS has failed because the value held at addr does not match expected.
+ // This may be a false negative because the version in memory might be
+ // the from-space version of the same object we currently hold to-space
+ // reference for.
+ //
+ // To resolve this, we need to pass the location through the LRB fixup,
+ // this will make sure that the location has only to-space pointers.
+ // To avoid calling into runtime often, we cset-check the object first.
+ // We can inline most of the work here, but there is little point,
+ // as CAS failures over cset locations must be rare. This fast-slow split
+ // matches what we do for normal LRB.
+
+ assert(_expected == rax, "expected must be rax");
+
+ // Non-strong references should always go to runtime. We do not expect
+ // CASes over non-strong locations.
+ assert((_node->barrier_data() & ShenandoahBarrierStrong) != 0, "Only strong references for CASes");
+
+ Label L_final;
+
+ // Fast-path stashed original oldval to tmp2 for us. We need to save it
+ // for the final retry. This frees up tmp2 for cset check below.
+ __ push(_tmp2);
+
+ // (Compressed) failure witness is in _expected.
+ // Unpack it and check if it is in collection set.
+ __ movptr(_tmp1, _expected);
+ if (UseCompressedOops) {
+ __ decode_heap_oop(_tmp1);
+ }
+ __ shrptr(_tmp1, ShenandoahHeapRegion::region_size_bytes_shift_jint());
+ __ movptr(_tmp2, (intptr_t) ShenandoahHeap::in_cset_fast_test_addr());
+ __ movbool(_tmp1, Address(_tmp1, _tmp2, Address::times_1));
+ __ testbool(_tmp1);
+ __ jcc(Assembler::zero, L_final);
+
+ {
+ SaveLiveRegisters save_registers(&masm, this);
+ // Load up failure witness again.
+ if (c_rarg0 != _expected) {
+ __ movptr(c_rarg0, _expected);
+ }
+ if (UseCompressedOops) {
+ __ decode_heap_oop(c_rarg0);
+ }
+ __ lea(c_rarg1, _addr);
+
+ if (UseCompressedOops) {
+ __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow), 2);
+ } else {
+ __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong), 2);
+ }
+ // We have called LRB to fix up the heap location. We do not care about its result,
+ // as we will just try to CAS the location again.
+ }
+
+ __ bind(L_final);
+
+ // Try to CAS again with the original expected value.
+ // At this point, there can no longer be false negatives.
+ __ pop(_expected);
+ __ lock();
+ if (UseCompressedOops) {
+ __ cmpxchgl(_new_val, _addr);
+ } else {
+ __ cmpxchgptr(_new_val, _addr);
+ }
+ if (!_cae) {
+ assert(_result != noreg, "need result register");
+ __ setcc(Assembler::equal, _result);
+ } else {
+ assert(_result == noreg, "no result expected");
+ }
+ __ jmp(*continuation());
+ }
+
+ #undef __
+ #define __ masm->
+ #endif
+
#ifdef PRODUCT
#define BLOCK_COMMENT(str) /* nothing */
#else
#define BLOCK_COMMENT(str) __ block_comment(str)
#endif
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