--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/oops/methodDataOop.hpp Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,1341 @@
+/*
+ * Copyright 2000-2007 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+class BytecodeStream;
+
+// The MethodData object collects counts and other profile information
+// during zeroth-tier (interpretive) and first-tier execution.
+// The profile is used later by compilation heuristics. Some heuristics
+// enable use of aggressive (or "heroic") optimizations. An aggressive
+// optimization often has a down-side, a corner case that it handles
+// poorly, but which is thought to be rare. The profile provides
+// evidence of this rarity for a given method or even BCI. It allows
+// the compiler to back out of the optimization at places where it
+// has historically been a poor choice. Other heuristics try to use
+// specific information gathered about types observed at a given site.
+//
+// All data in the profile is approximate. It is expected to be accurate
+// on the whole, but the system expects occasional inaccuraces, due to
+// counter overflow, multiprocessor races during data collection, space
+// limitations, missing MDO blocks, etc. Bad or missing data will degrade
+// optimization quality but will not affect correctness. Also, each MDO
+// is marked with its birth-date ("creation_mileage") which can be used
+// to assess the quality ("maturity") of its data.
+//
+// Short (<32-bit) counters are designed to overflow to a known "saturated"
+// state. Also, certain recorded per-BCI events are given one-bit counters
+// which overflow to a saturated state which applied to all counters at
+// that BCI. In other words, there is a small lattice which approximates
+// the ideal of an infinite-precision counter for each event at each BCI,
+// and the lattice quickly "bottoms out" in a state where all counters
+// are taken to be indefinitely large.
+//
+// The reader will find many data races in profile gathering code, starting
+// with invocation counter incrementation. None of these races harm correct
+// execution of the compiled code.
+
+// DataLayout
+//
+// Overlay for generic profiling data.
+class DataLayout VALUE_OBJ_CLASS_SPEC {
+private:
+ // Every data layout begins with a header. This header
+ // contains a tag, which is used to indicate the size/layout
+ // of the data, 4 bits of flags, which can be used in any way,
+ // 4 bits of trap history (none/one reason/many reasons),
+ // and a bci, which is used to tie this piece of data to a
+ // specific bci in the bytecodes.
+ union {
+ intptr_t _bits;
+ struct {
+ u1 _tag;
+ u1 _flags;
+ u2 _bci;
+ } _struct;
+ } _header;
+
+ // The data layout has an arbitrary number of cells, each sized
+ // to accomodate a pointer or an integer.
+ intptr_t _cells[1];
+
+ // Some types of data layouts need a length field.
+ static bool needs_array_len(u1 tag);
+
+public:
+ enum {
+ counter_increment = 1
+ };
+
+ enum {
+ cell_size = sizeof(intptr_t)
+ };
+
+ // Tag values
+ enum {
+ no_tag,
+ bit_data_tag,
+ counter_data_tag,
+ jump_data_tag,
+ receiver_type_data_tag,
+ virtual_call_data_tag,
+ ret_data_tag,
+ branch_data_tag,
+ multi_branch_data_tag
+ };
+
+ enum {
+ // The _struct._flags word is formatted as [trap_state:4 | flags:4].
+ // The trap state breaks down further as [recompile:1 | reason:3].
+ // This further breakdown is defined in deoptimization.cpp.
+ // See Deoptimization::trap_state_reason for an assert that
+ // trap_bits is big enough to hold reasons < Reason_RECORDED_LIMIT.
+ //
+ // The trap_state is collected only if ProfileTraps is true.
+ trap_bits = 1+3, // 3: enough to distinguish [0..Reason_RECORDED_LIMIT].
+ trap_shift = BitsPerByte - trap_bits,
+ trap_mask = right_n_bits(trap_bits),
+ trap_mask_in_place = (trap_mask << trap_shift),
+ flag_limit = trap_shift,
+ flag_mask = right_n_bits(flag_limit),
+ first_flag = 0
+ };
+
+ // Size computation
+ static int header_size_in_bytes() {
+ return cell_size;
+ }
+ static int header_size_in_cells() {
+ return 1;
+ }
+
+ static int compute_size_in_bytes(int cell_count) {
+ return header_size_in_bytes() + cell_count * cell_size;
+ }
+
+ // Initialization
+ void initialize(u1 tag, u2 bci, int cell_count);
+
+ // Accessors
+ u1 tag() {
+ return _header._struct._tag;
+ }
+
+ // Return a few bits of trap state. Range is [0..trap_mask].
+ // The state tells if traps with zero, one, or many reasons have occurred.
+ // It also tells whether zero or many recompilations have occurred.
+ // The associated trap histogram in the MDO itself tells whether
+ // traps are common or not. If a BCI shows that a trap X has
+ // occurred, and the MDO shows N occurrences of X, we make the
+ // simplifying assumption that all N occurrences can be blamed
+ // on that BCI.
+ int trap_state() {
+ return ((_header._struct._flags >> trap_shift) & trap_mask);
+ }
+
+ void set_trap_state(int new_state) {
+ assert(ProfileTraps, "used only under +ProfileTraps");
+ uint old_flags = (_header._struct._flags & flag_mask);
+ _header._struct._flags = (new_state << trap_shift) | old_flags;
+ assert(trap_state() == new_state, "sanity");
+ }
+
+ u1 flags() {
+ return _header._struct._flags;
+ }
+
+ u2 bci() {
+ return _header._struct._bci;
+ }
+
+ void set_header(intptr_t value) {
+ _header._bits = value;
+ }
+ void release_set_header(intptr_t value) {
+ OrderAccess::release_store_ptr(&_header._bits, value);
+ }
+ intptr_t header() {
+ return _header._bits;
+ }
+ void set_cell_at(int index, intptr_t value) {
+ _cells[index] = value;
+ }
+ void release_set_cell_at(int index, intptr_t value) {
+ OrderAccess::release_store_ptr(&_cells[index], value);
+ }
+ intptr_t cell_at(int index) {
+ return _cells[index];
+ }
+ intptr_t* adr_cell_at(int index) {
+ return &_cells[index];
+ }
+ oop* adr_oop_at(int index) {
+ return (oop*)&(_cells[index]);
+ }
+
+ void set_flag_at(int flag_number) {
+ assert(flag_number < flag_limit, "oob");
+ _header._struct._flags |= (0x1 << flag_number);
+ }
+ bool flag_at(int flag_number) {
+ assert(flag_number < flag_limit, "oob");
+ return (_header._struct._flags & (0x1 << flag_number)) != 0;
+ }
+
+ // Low-level support for code generation.
+ static ByteSize header_offset() {
+ return byte_offset_of(DataLayout, _header);
+ }
+ static ByteSize tag_offset() {
+ return byte_offset_of(DataLayout, _header._struct._tag);
+ }
+ static ByteSize flags_offset() {
+ return byte_offset_of(DataLayout, _header._struct._flags);
+ }
+ static ByteSize bci_offset() {
+ return byte_offset_of(DataLayout, _header._struct._bci);
+ }
+ static ByteSize cell_offset(int index) {
+ return byte_offset_of(DataLayout, _cells[index]);
+ }
+ // Return a value which, when or-ed as a byte into _flags, sets the flag.
+ static int flag_number_to_byte_constant(int flag_number) {
+ assert(0 <= flag_number && flag_number < flag_limit, "oob");
+ DataLayout temp; temp.set_header(0);
+ temp.set_flag_at(flag_number);
+ return temp._header._struct._flags;
+ }
+ // Return a value which, when or-ed as a word into _header, sets the flag.
+ static intptr_t flag_mask_to_header_mask(int byte_constant) {
+ DataLayout temp; temp.set_header(0);
+ temp._header._struct._flags = byte_constant;
+ return temp._header._bits;
+ }
+};
+
+
+// ProfileData class hierarchy
+class ProfileData;
+class BitData;
+class CounterData;
+class ReceiverTypeData;
+class VirtualCallData;
+class RetData;
+class JumpData;
+class BranchData;
+class ArrayData;
+class MultiBranchData;
+
+
+// ProfileData
+//
+// A ProfileData object is created to refer to a section of profiling
+// data in a structured way.
+class ProfileData : public ResourceObj {
+private:
+#ifndef PRODUCT
+ enum {
+ tab_width_one = 16,
+ tab_width_two = 36
+ };
+#endif // !PRODUCT
+
+ // This is a pointer to a section of profiling data.
+ DataLayout* _data;
+
+protected:
+ DataLayout* data() { return _data; }
+
+ enum {
+ cell_size = DataLayout::cell_size
+ };
+
+public:
+ // How many cells are in this?
+ virtual int cell_count() {
+ ShouldNotReachHere();
+ return -1;
+ }
+
+ // Return the size of this data.
+ int size_in_bytes() {
+ return DataLayout::compute_size_in_bytes(cell_count());
+ }
+
+protected:
+ // Low-level accessors for underlying data
+ void set_intptr_at(int index, intptr_t value) {
+ assert(0 <= index && index < cell_count(), "oob");
+ data()->set_cell_at(index, value);
+ }
+ void release_set_intptr_at(int index, intptr_t value) {
+ assert(0 <= index && index < cell_count(), "oob");
+ data()->release_set_cell_at(index, value);
+ }
+ intptr_t intptr_at(int index) {
+ assert(0 <= index && index < cell_count(), "oob");
+ return data()->cell_at(index);
+ }
+ void set_uint_at(int index, uint value) {
+ set_intptr_at(index, (intptr_t) value);
+ }
+ void release_set_uint_at(int index, uint value) {
+ release_set_intptr_at(index, (intptr_t) value);
+ }
+ uint uint_at(int index) {
+ return (uint)intptr_at(index);
+ }
+ void set_int_at(int index, int value) {
+ set_intptr_at(index, (intptr_t) value);
+ }
+ void release_set_int_at(int index, int value) {
+ release_set_intptr_at(index, (intptr_t) value);
+ }
+ int int_at(int index) {
+ return (int)intptr_at(index);
+ }
+ int int_at_unchecked(int index) {
+ return (int)data()->cell_at(index);
+ }
+ void set_oop_at(int index, oop value) {
+ set_intptr_at(index, (intptr_t) value);
+ }
+ oop oop_at(int index) {
+ return (oop)intptr_at(index);
+ }
+ oop* adr_oop_at(int index) {
+ assert(0 <= index && index < cell_count(), "oob");
+ return data()->adr_oop_at(index);
+ }
+
+ void set_flag_at(int flag_number) {
+ data()->set_flag_at(flag_number);
+ }
+ bool flag_at(int flag_number) {
+ return data()->flag_at(flag_number);
+ }
+
+ // two convenient imports for use by subclasses:
+ static ByteSize cell_offset(int index) {
+ return DataLayout::cell_offset(index);
+ }
+ static int flag_number_to_byte_constant(int flag_number) {
+ return DataLayout::flag_number_to_byte_constant(flag_number);
+ }
+
+ ProfileData(DataLayout* data) {
+ _data = data;
+ }
+
+public:
+ // Constructor for invalid ProfileData.
+ ProfileData();
+
+ u2 bci() {
+ return data()->bci();
+ }
+
+ address dp() {
+ return (address)_data;
+ }
+
+ int trap_state() {
+ return data()->trap_state();
+ }
+ void set_trap_state(int new_state) {
+ data()->set_trap_state(new_state);
+ }
+
+ // Type checking
+ virtual bool is_BitData() { return false; }
+ virtual bool is_CounterData() { return false; }
+ virtual bool is_JumpData() { return false; }
+ virtual bool is_ReceiverTypeData(){ return false; }
+ virtual bool is_VirtualCallData() { return false; }
+ virtual bool is_RetData() { return false; }
+ virtual bool is_BranchData() { return false; }
+ virtual bool is_ArrayData() { return false; }
+ virtual bool is_MultiBranchData() { return false; }
+
+ BitData* as_BitData() {
+ assert(is_BitData(), "wrong type");
+ return is_BitData() ? (BitData*) this : NULL;
+ }
+ CounterData* as_CounterData() {
+ assert(is_CounterData(), "wrong type");
+ return is_CounterData() ? (CounterData*) this : NULL;
+ }
+ JumpData* as_JumpData() {
+ assert(is_JumpData(), "wrong type");
+ return is_JumpData() ? (JumpData*) this : NULL;
+ }
+ ReceiverTypeData* as_ReceiverTypeData() {
+ assert(is_ReceiverTypeData(), "wrong type");
+ return is_ReceiverTypeData() ? (ReceiverTypeData*)this : NULL;
+ }
+ VirtualCallData* as_VirtualCallData() {
+ assert(is_VirtualCallData(), "wrong type");
+ return is_VirtualCallData() ? (VirtualCallData*)this : NULL;
+ }
+ RetData* as_RetData() {
+ assert(is_RetData(), "wrong type");
+ return is_RetData() ? (RetData*) this : NULL;
+ }
+ BranchData* as_BranchData() {
+ assert(is_BranchData(), "wrong type");
+ return is_BranchData() ? (BranchData*) this : NULL;
+ }
+ ArrayData* as_ArrayData() {
+ assert(is_ArrayData(), "wrong type");
+ return is_ArrayData() ? (ArrayData*) this : NULL;
+ }
+ MultiBranchData* as_MultiBranchData() {
+ assert(is_MultiBranchData(), "wrong type");
+ return is_MultiBranchData() ? (MultiBranchData*)this : NULL;
+ }
+
+
+ // Subclass specific initialization
+ virtual void post_initialize(BytecodeStream* stream, methodDataOop mdo) {}
+
+ // GC support
+ virtual void follow_contents() {}
+ virtual void oop_iterate(OopClosure* blk) {}
+ virtual void oop_iterate_m(OopClosure* blk, MemRegion mr) {}
+ virtual void adjust_pointers() {}
+
+#ifndef SERIALGC
+ // Parallel old support
+ virtual void follow_contents(ParCompactionManager* cm) {}
+ virtual void update_pointers() {}
+ virtual void update_pointers(HeapWord* beg_addr, HeapWord* end_addr) {}
+#endif // SERIALGC
+
+ // CI translation: ProfileData can represent both MethodDataOop data
+ // as well as CIMethodData data. This function is provided for translating
+ // an oop in a ProfileData to the ci equivalent. Generally speaking,
+ // most ProfileData don't require any translation, so we provide the null
+ // translation here, and the required translators are in the ci subclasses.
+ virtual void translate_from(ProfileData* data) {}
+
+ virtual void print_data_on(outputStream* st) {
+ ShouldNotReachHere();
+ }
+
+#ifndef PRODUCT
+ void print_shared(outputStream* st, const char* name);
+ void tab(outputStream* st);
+#endif
+};
+
+// BitData
+//
+// A BitData holds a flag or two in its header.
+class BitData : public ProfileData {
+protected:
+ enum {
+ // null_seen:
+ // saw a null operand (cast/aastore/instanceof)
+ null_seen_flag = DataLayout::first_flag + 0
+ };
+ enum { bit_cell_count = 0 }; // no additional data fields needed.
+public:
+ BitData(DataLayout* layout) : ProfileData(layout) {
+ }
+
+ virtual bool is_BitData() { return true; }
+
+ static int static_cell_count() {
+ return bit_cell_count;
+ }
+
+ virtual int cell_count() {
+ return static_cell_count();
+ }
+
+ // Accessor
+
+ // The null_seen flag bit is specially known to the interpreter.
+ // Consulting it allows the compiler to avoid setting up null_check traps.
+ bool null_seen() { return flag_at(null_seen_flag); }
+ void set_null_seen() { set_flag_at(null_seen_flag); }
+
+
+ // Code generation support
+ static int null_seen_byte_constant() {
+ return flag_number_to_byte_constant(null_seen_flag);
+ }
+
+ static ByteSize bit_data_size() {
+ return cell_offset(bit_cell_count);
+ }
+
+#ifndef PRODUCT
+ void print_data_on(outputStream* st);
+#endif
+};
+
+// CounterData
+//
+// A CounterData corresponds to a simple counter.
+class CounterData : public BitData {
+protected:
+ enum {
+ count_off,
+ counter_cell_count
+ };
+public:
+ CounterData(DataLayout* layout) : BitData(layout) {}
+
+ virtual bool is_CounterData() { return true; }
+
+ static int static_cell_count() {
+ return counter_cell_count;
+ }
+
+ virtual int cell_count() {
+ return static_cell_count();
+ }
+
+ // Direct accessor
+ uint count() {
+ return uint_at(count_off);
+ }
+
+ // Code generation support
+ static ByteSize count_offset() {
+ return cell_offset(count_off);
+ }
+ static ByteSize counter_data_size() {
+ return cell_offset(counter_cell_count);
+ }
+
+#ifndef PRODUCT
+ void print_data_on(outputStream* st);
+#endif
+};
+
+// JumpData
+//
+// A JumpData is used to access profiling information for a direct
+// branch. It is a counter, used for counting the number of branches,
+// plus a data displacement, used for realigning the data pointer to
+// the corresponding target bci.
+class JumpData : public ProfileData {
+protected:
+ enum {
+ taken_off_set,
+ displacement_off_set,
+ jump_cell_count
+ };
+
+ void set_displacement(int displacement) {
+ set_int_at(displacement_off_set, displacement);
+ }
+
+public:
+ JumpData(DataLayout* layout) : ProfileData(layout) {
+ assert(layout->tag() == DataLayout::jump_data_tag ||
+ layout->tag() == DataLayout::branch_data_tag, "wrong type");
+ }
+
+ virtual bool is_JumpData() { return true; }
+
+ static int static_cell_count() {
+ return jump_cell_count;
+ }
+
+ virtual int cell_count() {
+ return static_cell_count();
+ }
+
+ // Direct accessor
+ uint taken() {
+ return uint_at(taken_off_set);
+ }
+ // Saturating counter
+ uint inc_taken() {
+ uint cnt = taken() + 1;
+ // Did we wrap? Will compiler screw us??
+ if (cnt == 0) cnt--;
+ set_uint_at(taken_off_set, cnt);
+ return cnt;
+ }
+
+ int displacement() {
+ return int_at(displacement_off_set);
+ }
+
+ // Code generation support
+ static ByteSize taken_offset() {
+ return cell_offset(taken_off_set);
+ }
+
+ static ByteSize displacement_offset() {
+ return cell_offset(displacement_off_set);
+ }
+
+ // Specific initialization.
+ void post_initialize(BytecodeStream* stream, methodDataOop mdo);
+
+#ifndef PRODUCT
+ void print_data_on(outputStream* st);
+#endif
+};
+
+// ReceiverTypeData
+//
+// A ReceiverTypeData is used to access profiling information about a
+// dynamic type check. It consists of a counter which counts the total times
+// that the check is reached, and a series of (klassOop, count) pairs
+// which are used to store a type profile for the receiver of the check.
+class ReceiverTypeData : public CounterData {
+protected:
+ enum {
+ receiver0_offset = counter_cell_count,
+ count0_offset,
+ receiver_type_row_cell_count = (count0_offset + 1) - receiver0_offset
+ };
+
+public:
+ ReceiverTypeData(DataLayout* layout) : CounterData(layout) {
+ assert(layout->tag() == DataLayout::receiver_type_data_tag ||
+ layout->tag() == DataLayout::virtual_call_data_tag, "wrong type");
+ }
+
+ virtual bool is_ReceiverTypeData() { return true; }
+
+ static int static_cell_count() {
+ return counter_cell_count + (uint) TypeProfileWidth * receiver_type_row_cell_count;
+ }
+
+ virtual int cell_count() {
+ return static_cell_count();
+ }
+
+ // Direct accessors
+ static uint row_limit() {
+ return TypeProfileWidth;
+ }
+ static int receiver_cell_index(uint row) {
+ return receiver0_offset + row * receiver_type_row_cell_count;
+ }
+ static int receiver_count_cell_index(uint row) {
+ return count0_offset + row * receiver_type_row_cell_count;
+ }
+
+ // Get the receiver at row. The 'unchecked' version is needed by parallel old
+ // gc; it does not assert the receiver is a klass. During compaction of the
+ // perm gen, the klass may already have moved, so the is_klass() predicate
+ // would fail. The 'normal' version should be used whenever possible.
+ klassOop receiver_unchecked(uint row) {
+ assert(row < row_limit(), "oob");
+ oop recv = oop_at(receiver_cell_index(row));
+ return (klassOop)recv;
+ }
+
+ klassOop receiver(uint row) {
+ klassOop recv = receiver_unchecked(row);
+ assert(recv == NULL || ((oop)recv)->is_klass(), "wrong type");
+ return recv;
+ }
+
+ uint receiver_count(uint row) {
+ assert(row < row_limit(), "oob");
+ return uint_at(receiver_count_cell_index(row));
+ }
+
+ // Code generation support
+ static ByteSize receiver_offset(uint row) {
+ return cell_offset(receiver_cell_index(row));
+ }
+ static ByteSize receiver_count_offset(uint row) {
+ return cell_offset(receiver_count_cell_index(row));
+ }
+ static ByteSize receiver_type_data_size() {
+ return cell_offset(static_cell_count());
+ }
+
+ // GC support
+ virtual void follow_contents();
+ virtual void oop_iterate(OopClosure* blk);
+ virtual void oop_iterate_m(OopClosure* blk, MemRegion mr);
+ virtual void adjust_pointers();
+
+#ifndef SERIALGC
+ // Parallel old support
+ virtual void follow_contents(ParCompactionManager* cm);
+ virtual void update_pointers();
+ virtual void update_pointers(HeapWord* beg_addr, HeapWord* end_addr);
+#endif // SERIALGC
+
+ oop* adr_receiver(uint row) {
+ return adr_oop_at(receiver_cell_index(row));
+ }
+
+#ifndef PRODUCT
+ void print_receiver_data_on(outputStream* st);
+ void print_data_on(outputStream* st);
+#endif
+};
+
+// VirtualCallData
+//
+// A VirtualCallData is used to access profiling information about a
+// virtual call. For now, it has nothing more than a ReceiverTypeData.
+class VirtualCallData : public ReceiverTypeData {
+public:
+ VirtualCallData(DataLayout* layout) : ReceiverTypeData(layout) {
+ assert(layout->tag() == DataLayout::virtual_call_data_tag, "wrong type");
+ }
+
+ virtual bool is_VirtualCallData() { return true; }
+
+ static int static_cell_count() {
+ // At this point we could add more profile state, e.g., for arguments.
+ // But for now it's the same size as the base record type.
+ return ReceiverTypeData::static_cell_count();
+ }
+
+ virtual int cell_count() {
+ return static_cell_count();
+ }
+
+ // Direct accessors
+ static ByteSize virtual_call_data_size() {
+ return cell_offset(static_cell_count());
+ }
+
+#ifndef PRODUCT
+ void print_data_on(outputStream* st);
+#endif
+};
+
+// RetData
+//
+// A RetData is used to access profiling information for a ret bytecode.
+// It is composed of a count of the number of times that the ret has
+// been executed, followed by a series of triples of the form
+// (bci, count, di) which count the number of times that some bci was the
+// target of the ret and cache a corresponding data displacement.
+class RetData : public CounterData {
+protected:
+ enum {
+ bci0_offset = counter_cell_count,
+ count0_offset,
+ displacement0_offset,
+ ret_row_cell_count = (displacement0_offset + 1) - bci0_offset
+ };
+
+ void set_bci(uint row, int bci) {
+ assert((uint)row < row_limit(), "oob");
+ set_int_at(bci0_offset + row * ret_row_cell_count, bci);
+ }
+ void release_set_bci(uint row, int bci) {
+ assert((uint)row < row_limit(), "oob");
+ // 'release' when setting the bci acts as a valid flag for other
+ // threads wrt bci_count and bci_displacement.
+ release_set_int_at(bci0_offset + row * ret_row_cell_count, bci);
+ }
+ void set_bci_count(uint row, uint count) {
+ assert((uint)row < row_limit(), "oob");
+ set_uint_at(count0_offset + row * ret_row_cell_count, count);
+ }
+ void set_bci_displacement(uint row, int disp) {
+ set_int_at(displacement0_offset + row * ret_row_cell_count, disp);
+ }
+
+public:
+ RetData(DataLayout* layout) : CounterData(layout) {
+ assert(layout->tag() == DataLayout::ret_data_tag, "wrong type");
+ }
+
+ virtual bool is_RetData() { return true; }
+
+ enum {
+ no_bci = -1 // value of bci when bci1/2 are not in use.
+ };
+
+ static int static_cell_count() {
+ return counter_cell_count + (uint) BciProfileWidth * ret_row_cell_count;
+ }
+
+ virtual int cell_count() {
+ return static_cell_count();
+ }
+
+ static uint row_limit() {
+ return BciProfileWidth;
+ }
+ static int bci_cell_index(uint row) {
+ return bci0_offset + row * ret_row_cell_count;
+ }
+ static int bci_count_cell_index(uint row) {
+ return count0_offset + row * ret_row_cell_count;
+ }
+ static int bci_displacement_cell_index(uint row) {
+ return displacement0_offset + row * ret_row_cell_count;
+ }
+
+ // Direct accessors
+ int bci(uint row) {
+ return int_at(bci_cell_index(row));
+ }
+ uint bci_count(uint row) {
+ return uint_at(bci_count_cell_index(row));
+ }
+ int bci_displacement(uint row) {
+ return int_at(bci_displacement_cell_index(row));
+ }
+
+ // Interpreter Runtime support
+ address fixup_ret(int return_bci, methodDataHandle mdo);
+
+ // Code generation support
+ static ByteSize bci_offset(uint row) {
+ return cell_offset(bci_cell_index(row));
+ }
+ static ByteSize bci_count_offset(uint row) {
+ return cell_offset(bci_count_cell_index(row));
+ }
+ static ByteSize bci_displacement_offset(uint row) {
+ return cell_offset(bci_displacement_cell_index(row));
+ }
+
+ // Specific initialization.
+ void post_initialize(BytecodeStream* stream, methodDataOop mdo);
+
+#ifndef PRODUCT
+ void print_data_on(outputStream* st);
+#endif
+};
+
+// BranchData
+//
+// A BranchData is used to access profiling data for a two-way branch.
+// It consists of taken and not_taken counts as well as a data displacement
+// for the taken case.
+class BranchData : public JumpData {
+protected:
+ enum {
+ not_taken_off_set = jump_cell_count,
+ branch_cell_count
+ };
+
+ void set_displacement(int displacement) {
+ set_int_at(displacement_off_set, displacement);
+ }
+
+public:
+ BranchData(DataLayout* layout) : JumpData(layout) {
+ assert(layout->tag() == DataLayout::branch_data_tag, "wrong type");
+ }
+
+ virtual bool is_BranchData() { return true; }
+
+ static int static_cell_count() {
+ return branch_cell_count;
+ }
+
+ virtual int cell_count() {
+ return static_cell_count();
+ }
+
+ // Direct accessor
+ uint not_taken() {
+ return uint_at(not_taken_off_set);
+ }
+
+ uint inc_not_taken() {
+ uint cnt = not_taken() + 1;
+ // Did we wrap? Will compiler screw us??
+ if (cnt == 0) cnt--;
+ set_uint_at(not_taken_off_set, cnt);
+ return cnt;
+ }
+
+ // Code generation support
+ static ByteSize not_taken_offset() {
+ return cell_offset(not_taken_off_set);
+ }
+ static ByteSize branch_data_size() {
+ return cell_offset(branch_cell_count);
+ }
+
+ // Specific initialization.
+ void post_initialize(BytecodeStream* stream, methodDataOop mdo);
+
+#ifndef PRODUCT
+ void print_data_on(outputStream* st);
+#endif
+};
+
+// ArrayData
+//
+// A ArrayData is a base class for accessing profiling data which does
+// not have a statically known size. It consists of an array length
+// and an array start.
+class ArrayData : public ProfileData {
+protected:
+ friend class DataLayout;
+
+ enum {
+ array_len_off_set,
+ array_start_off_set
+ };
+
+ uint array_uint_at(int index) {
+ int aindex = index + array_start_off_set;
+ return uint_at(aindex);
+ }
+ int array_int_at(int index) {
+ int aindex = index + array_start_off_set;
+ return int_at(aindex);
+ }
+ oop array_oop_at(int index) {
+ int aindex = index + array_start_off_set;
+ return oop_at(aindex);
+ }
+ void array_set_int_at(int index, int value) {
+ int aindex = index + array_start_off_set;
+ set_int_at(aindex, value);
+ }
+
+ // Code generation support for subclasses.
+ static ByteSize array_element_offset(int index) {
+ return cell_offset(array_start_off_set + index);
+ }
+
+public:
+ ArrayData(DataLayout* layout) : ProfileData(layout) {}
+
+ virtual bool is_ArrayData() { return true; }
+
+ static int static_cell_count() {
+ return -1;
+ }
+
+ int array_len() {
+ return int_at_unchecked(array_len_off_set);
+ }
+
+ virtual int cell_count() {
+ return array_len() + 1;
+ }
+
+ // Code generation support
+ static ByteSize array_len_offset() {
+ return cell_offset(array_len_off_set);
+ }
+ static ByteSize array_start_offset() {
+ return cell_offset(array_start_off_set);
+ }
+};
+
+// MultiBranchData
+//
+// A MultiBranchData is used to access profiling information for
+// a multi-way branch (*switch bytecodes). It consists of a series
+// of (count, displacement) pairs, which count the number of times each
+// case was taken and specify the data displacment for each branch target.
+class MultiBranchData : public ArrayData {
+protected:
+ enum {
+ default_count_off_set,
+ default_disaplacement_off_set,
+ case_array_start
+ };
+ enum {
+ relative_count_off_set,
+ relative_displacement_off_set,
+ per_case_cell_count
+ };
+
+ void set_default_displacement(int displacement) {
+ array_set_int_at(default_disaplacement_off_set, displacement);
+ }
+ void set_displacement_at(int index, int displacement) {
+ array_set_int_at(case_array_start +
+ index * per_case_cell_count +
+ relative_displacement_off_set,
+ displacement);
+ }
+
+public:
+ MultiBranchData(DataLayout* layout) : ArrayData(layout) {
+ assert(layout->tag() == DataLayout::multi_branch_data_tag, "wrong type");
+ }
+
+ virtual bool is_MultiBranchData() { return true; }
+
+ static int compute_cell_count(BytecodeStream* stream);
+
+ int number_of_cases() {
+ int alen = array_len() - 2; // get rid of default case here.
+ assert(alen % per_case_cell_count == 0, "must be even");
+ return (alen / per_case_cell_count);
+ }
+
+ uint default_count() {
+ return array_uint_at(default_count_off_set);
+ }
+ int default_displacement() {
+ return array_int_at(default_disaplacement_off_set);
+ }
+
+ uint count_at(int index) {
+ return array_uint_at(case_array_start +
+ index * per_case_cell_count +
+ relative_count_off_set);
+ }
+ int displacement_at(int index) {
+ return array_int_at(case_array_start +
+ index * per_case_cell_count +
+ relative_displacement_off_set);
+ }
+
+ // Code generation support
+ static ByteSize default_count_offset() {
+ return array_element_offset(default_count_off_set);
+ }
+ static ByteSize default_displacement_offset() {
+ return array_element_offset(default_disaplacement_off_set);
+ }
+ static ByteSize case_count_offset(int index) {
+ return case_array_offset() +
+ (per_case_size() * index) +
+ relative_count_offset();
+ }
+ static ByteSize case_array_offset() {
+ return array_element_offset(case_array_start);
+ }
+ static ByteSize per_case_size() {
+ return in_ByteSize(per_case_cell_count) * cell_size;
+ }
+ static ByteSize relative_count_offset() {
+ return in_ByteSize(relative_count_off_set) * cell_size;
+ }
+ static ByteSize relative_displacement_offset() {
+ return in_ByteSize(relative_displacement_off_set) * cell_size;
+ }
+
+ // Specific initialization.
+ void post_initialize(BytecodeStream* stream, methodDataOop mdo);
+
+#ifndef PRODUCT
+ void print_data_on(outputStream* st);
+#endif
+};
+
+// methodDataOop
+//
+// A methodDataOop holds information which has been collected about
+// a method. Its layout looks like this:
+//
+// -----------------------------
+// | header |
+// | klass |
+// -----------------------------
+// | method |
+// | size of the methodDataOop |
+// -----------------------------
+// | Data entries... |
+// | (variable size) |
+// | |
+// . .
+// . .
+// . .
+// | |
+// -----------------------------
+//
+// The data entry area is a heterogeneous array of DataLayouts. Each
+// DataLayout in the array corresponds to a specific bytecode in the
+// method. The entries in the array are sorted by the corresponding
+// bytecode. Access to the data is via resource-allocated ProfileData,
+// which point to the underlying blocks of DataLayout structures.
+//
+// During interpretation, if profiling in enabled, the interpreter
+// maintains a method data pointer (mdp), which points at the entry
+// in the array corresponding to the current bci. In the course of
+// intepretation, when a bytecode is encountered that has profile data
+// associated with it, the entry pointed to by mdp is updated, then the
+// mdp is adjusted to point to the next appropriate DataLayout. If mdp
+// is NULL to begin with, the interpreter assumes that the current method
+// is not (yet) being profiled.
+//
+// In methodDataOop parlance, "dp" is a "data pointer", the actual address
+// of a DataLayout element. A "di" is a "data index", the offset in bytes
+// from the base of the data entry array. A "displacement" is the byte offset
+// in certain ProfileData objects that indicate the amount the mdp must be
+// adjusted in the event of a change in control flow.
+//
+
+class methodDataOopDesc : public oopDesc {
+ friend class VMStructs;
+private:
+ friend class ProfileData;
+
+ // Back pointer to the methodOop
+ methodOop _method;
+
+ // Size of this oop in bytes
+ int _size;
+
+ // Cached hint for bci_to_dp and bci_to_data
+ int _hint_di;
+
+ // Whole-method sticky bits and flags
+public:
+ enum {
+ _trap_hist_limit = 16, // decoupled from Deoptimization::Reason_LIMIT
+ _trap_hist_mask = max_jubyte,
+ _extra_data_count = 4 // extra DataLayout headers, for trap history
+ }; // Public flag values
+private:
+ uint _nof_decompiles; // count of all nmethod removals
+ uint _nof_overflow_recompiles; // recompile count, excluding recomp. bits
+ uint _nof_overflow_traps; // trap count, excluding _trap_hist
+ union {
+ intptr_t _align;
+ u1 _array[_trap_hist_limit];
+ } _trap_hist;
+
+ // Support for interprocedural escape analysis, from Thomas Kotzmann.
+ intx _eflags; // flags on escape information
+ intx _arg_local; // bit set of non-escaping arguments
+ intx _arg_stack; // bit set of stack-allocatable arguments
+ intx _arg_returned; // bit set of returned arguments
+
+ int _creation_mileage; // method mileage at MDO creation
+
+ // Size of _data array in bytes. (Excludes header and extra_data fields.)
+ int _data_size;
+
+ // Beginning of the data entries
+ intptr_t _data[1];
+
+ // Helper for size computation
+ static int compute_data_size(BytecodeStream* stream);
+ static int bytecode_cell_count(Bytecodes::Code code);
+ enum { no_profile_data = -1, variable_cell_count = -2 };
+
+ // Helper for initialization
+ DataLayout* data_layout_at(int data_index) {
+ assert(data_index % sizeof(intptr_t) == 0, "unaligned");
+ return (DataLayout*) (((address)_data) + data_index);
+ }
+
+ // Initialize an individual data segment. Returns the size of
+ // the segment in bytes.
+ int initialize_data(BytecodeStream* stream, int data_index);
+
+ // Helper for data_at
+ DataLayout* limit_data_position() {
+ return (DataLayout*)((address)data_base() + _data_size);
+ }
+ bool out_of_bounds(int data_index) {
+ return data_index >= data_size();
+ }
+
+ // Give each of the data entries a chance to perform specific
+ // data initialization.
+ void post_initialize(BytecodeStream* stream);
+
+ // hint accessors
+ int hint_di() const { return _hint_di; }
+ void set_hint_di(int di) {
+ assert(!out_of_bounds(di), "hint_di out of bounds");
+ _hint_di = di;
+ }
+ ProfileData* data_before(int bci) {
+ // avoid SEGV on this edge case
+ if (data_size() == 0)
+ return NULL;
+ int hint = hint_di();
+ if (data_layout_at(hint)->bci() <= bci)
+ return data_at(hint);
+ return first_data();
+ }
+
+ // What is the index of the first data entry?
+ int first_di() { return 0; }
+
+ // Find or create an extra ProfileData:
+ ProfileData* bci_to_extra_data(int bci, bool create_if_missing);
+
+public:
+ static int header_size() {
+ return sizeof(methodDataOopDesc)/wordSize;
+ }
+
+ // Compute the size of a methodDataOop before it is created.
+ static int compute_allocation_size_in_bytes(methodHandle method);
+ static int compute_allocation_size_in_words(methodHandle method);
+ static int compute_extra_data_count(int data_size, int empty_bc_count);
+
+ // Determine if a given bytecode can have profile information.
+ static bool bytecode_has_profile(Bytecodes::Code code) {
+ return bytecode_cell_count(code) != no_profile_data;
+ }
+
+ // Perform initialization of a new methodDataOop
+ void initialize(methodHandle method);
+
+ // My size
+ int object_size_in_bytes() { return _size; }
+ int object_size() {
+ return align_object_size(align_size_up(_size, BytesPerWord)/BytesPerWord);
+ }
+
+ int creation_mileage() const { return _creation_mileage; }
+ void set_creation_mileage(int x) { _creation_mileage = x; }
+ bool is_mature() const; // consult mileage and ProfileMaturityPercentage
+ static int mileage_of(methodOop m);
+
+ // Support for interprocedural escape analysis, from Thomas Kotzmann.
+ enum EscapeFlag {
+ estimated = 1 << 0,
+ return_local = 1 << 1
+ };
+
+ intx eflags() { return _eflags; }
+ intx arg_local() { return _arg_local; }
+ intx arg_stack() { return _arg_stack; }
+ intx arg_returned() { return _arg_returned; }
+
+ void set_eflags(intx v) { _eflags = v; }
+ void set_arg_local(intx v) { _arg_local = v; }
+ void set_arg_stack(intx v) { _arg_stack = v; }
+ void set_arg_returned(intx v) { _arg_returned = v; }
+
+ void clear_escape_info() { _eflags = _arg_local = _arg_stack = _arg_returned = 0; }
+
+ // Location and size of data area
+ address data_base() const {
+ return (address) _data;
+ }
+ int data_size() {
+ return _data_size;
+ }
+
+ // Accessors
+ methodOop method() { return _method; }
+
+ // Get the data at an arbitrary (sort of) data index.
+ ProfileData* data_at(int data_index);
+
+ // Walk through the data in order.
+ ProfileData* first_data() { return data_at(first_di()); }
+ ProfileData* next_data(ProfileData* current);
+ bool is_valid(ProfileData* current) { return current != NULL; }
+
+ // Convert a dp (data pointer) to a di (data index).
+ int dp_to_di(address dp) {
+ return dp - ((address)_data);
+ }
+
+ address di_to_dp(int di) {
+ return (address)data_layout_at(di);
+ }
+
+ // bci to di/dp conversion.
+ address bci_to_dp(int bci);
+ int bci_to_di(int bci) {
+ return dp_to_di(bci_to_dp(bci));
+ }
+
+ // Get the data at an arbitrary bci, or NULL if there is none.
+ ProfileData* bci_to_data(int bci);
+
+ // Same, but try to create an extra_data record if one is needed:
+ ProfileData* allocate_bci_to_data(int bci) {
+ ProfileData* data = bci_to_data(bci);
+ return (data != NULL) ? data : bci_to_extra_data(bci, true);
+ }
+
+ // Add a handful of extra data records, for trap tracking.
+ DataLayout* extra_data_base() { return limit_data_position(); }
+ DataLayout* extra_data_limit() { return (DataLayout*)((address)this + object_size_in_bytes()); }
+ int extra_data_size() { return (address)extra_data_limit()
+ - (address)extra_data_base(); }
+ static DataLayout* next_extra(DataLayout* dp) { return (DataLayout*)((address)dp + in_bytes(DataLayout::cell_offset(0))); }
+
+ // Return (uint)-1 for overflow.
+ uint trap_count(int reason) const {
+ assert((uint)reason < _trap_hist_limit, "oob");
+ return (int)((_trap_hist._array[reason]+1) & _trap_hist_mask) - 1;
+ }
+ // For loops:
+ static uint trap_reason_limit() { return _trap_hist_limit; }
+ static uint trap_count_limit() { return _trap_hist_mask; }
+ uint inc_trap_count(int reason) {
+ // Count another trap, anywhere in this method.
+ assert(reason >= 0, "must be single trap");
+ if ((uint)reason < _trap_hist_limit) {
+ uint cnt1 = 1 + _trap_hist._array[reason];
+ if ((cnt1 & _trap_hist_mask) != 0) { // if no counter overflow...
+ _trap_hist._array[reason] = cnt1;
+ return cnt1;
+ } else {
+ return _trap_hist_mask + (++_nof_overflow_traps);
+ }
+ } else {
+ // Could not represent the count in the histogram.
+ return (++_nof_overflow_traps);
+ }
+ }
+
+ uint overflow_trap_count() const {
+ return _nof_overflow_traps;
+ }
+ uint overflow_recompile_count() const {
+ return _nof_overflow_recompiles;
+ }
+ void inc_overflow_recompile_count() {
+ _nof_overflow_recompiles += 1;
+ }
+ uint decompile_count() const {
+ return _nof_decompiles;
+ }
+ void inc_decompile_count() {
+ _nof_decompiles += 1;
+ }
+
+ // Support for code generation
+ static ByteSize data_offset() {
+ return byte_offset_of(methodDataOopDesc, _data[0]);
+ }
+
+ // GC support
+ oop* adr_method() const { return (oop*)&_method; }
+ bool object_is_parsable() const { return _size != 0; }
+ void set_object_is_parsable(int object_size_in_bytes) { _size = object_size_in_bytes; }
+
+#ifndef PRODUCT
+ // printing support for method data
+ void print_data_on(outputStream* st);
+#endif
+
+ // verification
+ void verify_data_on(outputStream* st);
+};