static void assert_params_ok(void* from, void* to, intptr_t log_align) { #ifdef ASSERT if (mask_bits((uintptr_t)from, right_n_bits(log_align)) != 0) basic_fatal("not aligned"); if (mask_bits((uintptr_t)to, right_n_bits(log_align)) != 0) basic_fatal("not aligned"); #endif }
static void pd_fill_to_words(HeapWord* tohw, size_t count, juint value) { #ifdef _LP64 guarantee(mask_bits((uintptr_t)tohw, right_n_bits(LogBytesPerLong)) == 0, "unaligned fill words"); julong* to = (julong*)tohw; julong v = ((julong)value << 32) | value; while (count-- > 0) { *to++ = v; } #else // _LP64 juint* to = (juint*)tohw; while (count-- > 0) { *to++ = value; } #endif // _LP64 }
enum { bit_index_length = 5, word_index_length = 3, block_index_length = 8 // not used }; // Derived constants used for manipulating the index bitfields enum { bit_index_offset = 0, // not used word_index_offset = bit_index_length, block_index_offset = bit_index_length + word_index_length, bits_per_word = 1 << bit_index_length, words_per_block = 1 << word_index_length, bits_per_block = bits_per_word * words_per_block, bit_index_mask = right_n_bits(bit_index_length), word_index_mask = right_n_bits(word_index_length) }; // These routines are used for extracting the block, word, and bit index // from an element. static uint get_block_index(uint element) { return element >> block_index_offset; } static uint get_word_index(uint element) { return mask_bits(element >> word_index_offset,word_index_mask); } static uint get_bit_index(uint element) { return mask_bits(element,bit_index_mask); }
bool G1BlockOffsetSharedArray::is_card_boundary(HeapWord* p) const { assert(p >= _reserved.start(), "just checking"); size_t delta = pointer_delta(p, _reserved.start()); return (delta & right_n_bits(LogN_words)) == (size_t)NoBits; }
// Action_mark - update the BOT for the block [blk_start, blk_end). // Current typical use is for splitting a block. // Action_single - update the BOT for an allocation. // Action_verify - BOT verification. void G1BlockOffsetArray::do_block_internal(HeapWord* blk_start, HeapWord* blk_end, Action action) { assert(Universe::heap()->is_in_reserved(blk_start), "reference must be into the heap"); assert(Universe::heap()->is_in_reserved(blk_end-1), "limit must be within the heap"); // This is optimized to make the test fast, assuming we only rarely // cross boundaries. uintptr_t end_ui = (uintptr_t)(blk_end - 1); uintptr_t start_ui = (uintptr_t)blk_start; // Calculate the last card boundary preceding end of blk intptr_t boundary_before_end = (intptr_t)end_ui; clear_bits(boundary_before_end, right_n_bits(LogN)); if (start_ui <= (uintptr_t)boundary_before_end) { // blk starts at or crosses a boundary // Calculate index of card on which blk begins size_t start_index = _array->index_for(blk_start); // Index of card on which blk ends size_t end_index = _array->index_for(blk_end - 1); // Start address of card on which blk begins HeapWord* boundary = _array->address_for_index(start_index); assert(boundary <= blk_start, "blk should start at or after boundary"); if (blk_start != boundary) { // blk starts strictly after boundary // adjust card boundary and start_index forward to next card boundary += N_words; start_index++; } assert(start_index <= end_index, "monotonicity of index_for()"); assert(boundary <= (HeapWord*)boundary_before_end, "tautology"); switch (action) { case Action_mark: { if (init_to_zero()) { _array->set_offset_array(start_index, boundary, blk_start); break; } // Else fall through to the next case } case Action_single: { _array->set_offset_array(start_index, boundary, blk_start); // We have finished marking the "offset card". We need to now // mark the subsequent cards that this blk spans. if (start_index < end_index) { HeapWord* rem_st = _array->address_for_index(start_index) + N_words; HeapWord* rem_end = _array->address_for_index(end_index) + N_words; set_remainder_to_point_to_start(rem_st, rem_end); } break; } case Action_check: { _array->check_offset_array(start_index, boundary, blk_start); // We have finished checking the "offset card". We need to now // check the subsequent cards that this blk spans. check_all_cards(start_index + 1, end_index); break; } default: ShouldNotReachHere(); } } }
* */ #ifndef SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_PROMOTIONINFO_HPP #define SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_PROMOTIONINFO_HPP #include "gc_implementation/concurrentMarkSweep/freeChunk.hpp" #include "memory/allocation.hpp" // Forward declarations class CompactibleFreeListSpace; class PromotedObject VALUE_OBJ_CLASS_SPEC { private: enum { promoted_mask = right_n_bits(2), // i.e. 0x3 displaced_mark = nth_bit(2), // i.e. 0x4 next_mask = ~(right_n_bits(3)) // i.e. ~(0x7) }; // Below, we want _narrow_next in the "higher" 32 bit slot, // whose position will depend on endian-ness of the platform. // This is so that there is no interference with the // cms_free_bit occupying bit position 7 (lsb == 0) // when we are using compressed oops; see FreeChunk::is_free(). // We cannot move the cms_free_bit down because currently // biased locking code assumes that age bits are contiguous // with the lock bits. Even if that assumption were relaxed, // the least position we could move this bit to would be // to bit position 3, which would require 16 byte alignment. typedef struct {
vmIntrinsics::Flags vmIntrinsics::flags_for(vmIntrinsics::ID id) { jlong info = intrinsic_info(id); int shift = 0, mask = right_n_bits(log2_FLAG_LIMIT); assert(((ID4(1021,1022,1023,15) >> shift) & mask) == 15, ""); return Flags( (info >> shift) & mask ); }
vmSymbols::SID vmIntrinsics::signature_for(vmIntrinsics::ID id) { jlong info = intrinsic_info(id); int shift = log2_FLAG_LIMIT, mask = right_n_bits(vmSymbols::log2_SID_LIMIT); assert(((ID4(1021,1022,1023,15) >> shift) & mask) == 1023, ""); return vmSymbols::SID( (info >> shift) & mask ); }
// more significant bits. The counter is incremented before a method is activated and an // action is triggered when when count() > limit(). class InvocationCounter VALUE_OBJ_CLASS_SPEC { friend class VMStructs; private: // bit no: |31 3| 2 | 1 0 | unsigned int _counter; // format: [count|carry|state] enum PrivateConstants { number_of_state_bits = 2, number_of_carry_bits = 1, number_of_noncount_bits = number_of_state_bits + number_of_carry_bits, number_of_count_bits = BitsPerInt - number_of_noncount_bits, state_limit = nth_bit(number_of_state_bits), count_grain = nth_bit(number_of_state_bits + number_of_carry_bits), carry_mask = right_n_bits(number_of_carry_bits) << number_of_state_bits, state_mask = right_n_bits(number_of_state_bits), status_mask = right_n_bits(number_of_state_bits + number_of_carry_bits), count_mask = ((int)(-1) ^ status_mask) }; public: static int InterpreterInvocationLimit; // CompileThreshold scaled for interpreter use static int InterpreterBackwardBranchLimit; // A separate threshold for on stack replacement static int InterpreterProfileLimit; // Profiling threshold scaled for interpreter use typedef address (*Action)(methodHandle method, TRAPS); enum PublicConstants { count_increment = count_grain, // use this value to increment the 32bit _counter word count_mask_value = count_mask, // use this value to mask the backedge counter
friend class StubGenerator; public: enum { nof_instance_allocators = 10 }; // allocator lock values enum { unlocked = 0, locked = 1 }; enum { v8_oop_lock_ignore_bits = 2, v8_oop_lock_bits = 4, nof_v8_oop_lock_cache_entries = 1 << (v8_oop_lock_bits+v8_oop_lock_ignore_bits), v8_oop_lock_mask = right_n_bits(v8_oop_lock_bits), v8_oop_lock_mask_in_place = v8_oop_lock_mask << v8_oop_lock_ignore_bits }; static int _v8_oop_lock_cache[nof_v8_oop_lock_cache_entries]; private: static address _test_stop_entry; static address _stop_subroutine_entry; static address _flush_callers_register_windows_entry; static address _copy_words_aligned8_lower_entry; static address _copy_words_aligned8_higher_entry; static address _set_words_aligned8_entry; static address _zero_words_aligned8_entry;
checked_bits = 1, instance_bits = 1, address_bits = BitsPerWord - checked_bits - instance_bits, large_offset_bits = address_bits, // unioned with address small_offset_bits = 7, klass_bits = address_bits - small_offset_bits, checked_shift = 0, instance_shift = checked_shift + checked_bits, address_shift = instance_shift + instance_bits, offset_shift = address_shift, // unioned with address klass_shift = offset_shift + small_offset_bits, checked_mask_in_place = right_n_bits(checked_bits) << checked_shift, instance_mask_in_place = right_n_bits(instance_bits) << instance_shift, #ifndef _WIN64 large_offset_mask = right_n_bits(large_offset_bits), small_offset_mask = right_n_bits(small_offset_bits), klass_mask = right_n_bits(klass_bits) #endif }; #ifdef _WIN64 // These values are too big for Win64 const static uintptr_t large_offset_mask = right_n_bits(large_offset_bits); const static uintptr_t small_offset_mask = right_n_bits(small_offset_bits); const static uintptr_t klass_mask = right_n_bits(klass_bits); #endif
checked_bits = 1, instance_bits = 1, address_bits = BitsPerWord - checked_bits - instance_bits, large_offset_bits = address_bits, // unioned with address small_offset_bits = 7, klass_bits = address_bits - small_offset_bits, checked_shift = 0, instance_shift = checked_shift + checked_bits, address_shift = instance_shift + instance_bits, offset_shift = address_shift, // unioned with address klass_shift = offset_shift + small_offset_bits, checked_mask_in_place = right_n_bits(checked_bits) << checked_shift, instance_mask_in_place = right_n_bits(instance_bits) << instance_shift, large_offset_mask = right_n_bits(large_offset_bits), small_offset_mask = right_n_bits(small_offset_bits), klass_mask = right_n_bits(klass_bits) }; // helper routines: static bool is_checked_jfieldID(jfieldID id) { uintptr_t as_uint = (uintptr_t) id; return ((as_uint & checked_mask_in_place) != 0); } static intptr_t encode_klass_hash(klassOop k, intptr_t offset); static bool klass_hash_ok(klassOop k, jfieldID id); static void verify_instance_jfieldID(klassOop k, jfieldID id);
// Helper to remove argument slots from the stack. // arg_slots must be a multiple of stack_move_unit() and >= 0 void MethodHandles::remove_arg_slots(MacroAssembler* _masm, RegisterOrConstant arg_slots, Register argslot_reg, Register temp_reg, Register temp2_reg, Register temp3_reg) { assert(temp3_reg != noreg, "temp3 required"); assert_different_registers(argslot_reg, temp_reg, temp2_reg, temp3_reg, (!arg_slots.is_register() ? Gargs : arg_slots.as_register())); RegisterOrConstant offset = __ regcon_sll_ptr(arg_slots, LogBytesPerWord, temp3_reg); #ifdef ASSERT // Verify that [argslot..argslot+size) lies within (Gargs, FP). __ add(argslot_reg, offset, temp2_reg); verify_argslot(_masm, temp2_reg, temp_reg, "deleted argument(s) must fall within current frame"); if (arg_slots.is_register()) { Label L_ok, L_bad; __ cmp(arg_slots.as_register(), (int32_t) NULL_WORD); __ br(Assembler::less, false, Assembler::pn, L_bad); __ delayed()->nop(); __ btst(-stack_move_unit() - 1, arg_slots.as_register()); __ br(Assembler::zero, false, Assembler::pt, L_ok); __ delayed()->nop(); __ bind(L_bad); __ stop("assert arg_slots >= 0 and clear low bits"); __ bind(L_ok); } else { assert(arg_slots.as_constant() >= 0, ""); assert(arg_slots.as_constant() % -stack_move_unit() == 0, ""); } #endif // ASSERT // Pull up everything shallower than argslot. // Then remove the excess space on the stack. // The stacked return address gets pulled up with everything else. // That is, copy [sp, argslot) upward by size words. In pseudo-code: // for (temp = argslot-1; temp >= sp; --temp) // temp[size] = temp[0] // argslot += size; // sp += size; __ sub(argslot_reg, wordSize, temp_reg); // source pointer for copy { Label loop; __ bind(loop); // pull one word up each time through the loop __ ld_ptr(Address(temp_reg, 0), temp2_reg); __ st_ptr(temp2_reg, Address(temp_reg, offset)); __ sub(temp_reg, wordSize, temp_reg); __ cmp(temp_reg, Gargs); __ brx(Assembler::greaterEqual, false, Assembler::pt, loop); __ delayed()->nop(); // FILLME } // Now move the argslot up, to point to the just-copied block. __ add(Gargs, offset, Gargs); // And adjust the argslot address to point at the deletion point. __ add(argslot_reg, offset, argslot_reg); // Keep the stack pointer 2*wordSize aligned. const int TwoWordAlignmentMask = right_n_bits(LogBytesPerWord + 1); RegisterOrConstant masked_offset = __ regcon_andn_ptr(offset, TwoWordAlignmentMask, temp_reg); __ add(SP, masked_offset, SP); }
// Helper to insert argument slots into the stack. // arg_slots must be a multiple of stack_move_unit() and <= 0 void MethodHandles::insert_arg_slots(MacroAssembler* _masm, RegisterOrConstant arg_slots, int arg_mask, Register argslot_reg, Register temp_reg, Register temp2_reg, Register temp3_reg) { assert(temp3_reg != noreg, "temp3 required"); assert_different_registers(argslot_reg, temp_reg, temp2_reg, temp3_reg, (!arg_slots.is_register() ? Gargs : arg_slots.as_register())); #ifdef ASSERT verify_argslot(_masm, argslot_reg, temp_reg, "insertion point must fall within current frame"); if (arg_slots.is_register()) { Label L_ok, L_bad; __ cmp(arg_slots.as_register(), (int32_t) NULL_WORD); __ br(Assembler::greater, false, Assembler::pn, L_bad); __ delayed()->nop(); __ btst(-stack_move_unit() - 1, arg_slots.as_register()); __ br(Assembler::zero, false, Assembler::pt, L_ok); __ delayed()->nop(); __ bind(L_bad); __ stop("assert arg_slots <= 0 and clear low bits"); __ bind(L_ok); } else { assert(arg_slots.as_constant() <= 0, ""); assert(arg_slots.as_constant() % -stack_move_unit() == 0, ""); } #endif // ASSERT #ifdef _LP64 if (arg_slots.is_register()) { // Was arg_slots register loaded as signed int? Label L_ok; __ sll(arg_slots.as_register(), BitsPerInt, temp_reg); __ sra(temp_reg, BitsPerInt, temp_reg); __ cmp(arg_slots.as_register(), temp_reg); __ br(Assembler::equal, false, Assembler::pt, L_ok); __ delayed()->nop(); __ stop("arg_slots register not loaded as signed int"); __ bind(L_ok); } #endif // Make space on the stack for the inserted argument(s). // Then pull down everything shallower than argslot_reg. // The stacked return address gets pulled down with everything else. // That is, copy [sp, argslot) downward by -size words. In pseudo-code: // sp -= size; // for (temp = sp + size; temp < argslot; temp++) // temp[-size] = temp[0] // argslot -= size; RegisterOrConstant offset = __ regcon_sll_ptr(arg_slots, LogBytesPerWord, temp3_reg); // Keep the stack pointer 2*wordSize aligned. const int TwoWordAlignmentMask = right_n_bits(LogBytesPerWord + 1); RegisterOrConstant masked_offset = __ regcon_andn_ptr(offset, TwoWordAlignmentMask, temp_reg); __ add(SP, masked_offset, SP); __ mov(Gargs, temp_reg); // source pointer for copy __ add(Gargs, offset, Gargs); { Label loop; __ bind(loop); // pull one word down each time through the loop __ ld_ptr(Address(temp_reg, 0), temp2_reg); __ st_ptr(temp2_reg, Address(temp_reg, offset)); __ add(temp_reg, wordSize, temp_reg); __ cmp(temp_reg, argslot_reg); __ brx(Assembler::less, false, Assembler::pt, loop); __ delayed()->nop(); // FILLME } // Now move the argslot down, to point to the opened-up space. __ add(argslot_reg, offset, argslot_reg); }