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/*
! * Copyright (c) 1997, 2023, Oracle and/or its affiliates. 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.
/*
! * Copyright (c) 1997, 2024, Oracle and/or its affiliates. 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.
#include "runtime/stubRoutines.hpp"
#include "runtime/thread.hpp"
#include "utilities/macros.hpp"
#include "crc32c.h"
+ #ifdef COMPILER2
+ #include "opto/c2_CodeStubs.hpp"
+ #include "opto/compile.hpp"
+ #include "opto/output.hpp"
+ #endif
+
#ifdef PRODUCT
#define BLOCK_COMMENT(str) /* nothing */
#define STOP(error) stop(error)
#else
#define BLOCK_COMMENT(str) block_comment(str)
}
// Preserves the contents of address, destroys the contents length_in_bytes and temp.
void MacroAssembler::zero_memory(Register address, Register length_in_bytes, int offset_in_bytes, Register temp) {
assert(address != length_in_bytes && address != temp && temp != length_in_bytes, "registers must be different");
! assert((offset_in_bytes & (BytesPerWord - 1)) == 0, "offset must be a multiple of BytesPerWord");
Label done;
testptr(length_in_bytes, length_in_bytes);
jcc(Assembler::zero, done);
// initialize topmost word, divide index by 2, check if odd and test if zero
// note: for the remaining code to work, index must be a multiple of BytesPerWord
#ifdef ASSERT
{
Label L;
}
// Preserves the contents of address, destroys the contents length_in_bytes and temp.
void MacroAssembler::zero_memory(Register address, Register length_in_bytes, int offset_in_bytes, Register temp) {
assert(address != length_in_bytes && address != temp && temp != length_in_bytes, "registers must be different");
! assert((offset_in_bytes & (BytesPerInt - 1)) == 0, "offset must be a multiple of BytesPerInt");
Label done;
testptr(length_in_bytes, length_in_bytes);
jcc(Assembler::zero, done);
+ // Emit single 32bit store to clear leading bytes, if necessary.
+ xorptr(temp, temp); // use _zero reg to clear memory (shorter code)
+ #ifdef _LP64
+ if (!is_aligned(offset_in_bytes, BytesPerWord)) {
+ movl(Address(address, offset_in_bytes), temp);
+ offset_in_bytes += BytesPerInt;
+ decrement(length_in_bytes, BytesPerInt);
+ }
+ assert((offset_in_bytes & (BytesPerWord - 1)) == 0, "offset must be a multiple of BytesPerWord");
+ testptr(length_in_bytes, length_in_bytes);
+ jcc(Assembler::zero, done);
+ #endif
+
// initialize topmost word, divide index by 2, check if odd and test if zero
// note: for the remaining code to work, index must be a multiple of BytesPerWord
#ifdef ASSERT
{
Label L;
stop("length must be a multiple of BytesPerWord");
bind(L);
}
#endif
Register index = length_in_bytes;
- xorptr(temp, temp); // use _zero reg to clear memory (shorter code)
if (UseIncDec) {
shrptr(index, 3); // divide by 8/16 and set carry flag if bit 2 was set
} else {
shrptr(index, 2); // use 2 instructions to avoid partial flag stall
shrptr(index, 1);
movptr(holder, Address(method, Method::const_offset())); // ConstMethod*
movptr(holder, Address(holder, ConstMethod::constants_offset())); // ConstantPool*
movptr(holder, Address(holder, ConstantPool::pool_holder_offset_in_bytes())); // InstanceKlass*
}
! void MacroAssembler::load_klass(Register dst, Register src, Register tmp) {
assert_different_registers(src, tmp);
assert_different_registers(dst, tmp);
#ifdef _LP64
if (UseCompressedClassPointers) {
! movl(dst, Address(src, oopDesc::klass_offset_in_bytes()));
decode_klass_not_null(dst, tmp);
} else
#endif
movptr(dst, Address(src, oopDesc::klass_offset_in_bytes()));
}
movptr(holder, Address(method, Method::const_offset())); // ConstMethod*
movptr(holder, Address(holder, ConstMethod::constants_offset())); // ConstantPool*
movptr(holder, Address(holder, ConstantPool::pool_holder_offset_in_bytes())); // InstanceKlass*
}
! #ifdef _LP64
+ void MacroAssembler::load_nklass(Register dst, Register src) {
+ assert(UseCompressedClassPointers, "expect compressed class pointers");
+
+ if (!UseCompactObjectHeaders) {
+ movl(dst, Address(src, oopDesc::klass_offset_in_bytes()));
+ return;
+ }
+
+ Label fast;
+ movq(dst, Address(src, oopDesc::mark_offset_in_bytes()));
+ testb(dst, markWord::monitor_value);
+ jccb(Assembler::zero, fast);
+
+ // Fetch displaced header
+ movq(dst, Address(dst, OM_OFFSET_NO_MONITOR_VALUE_TAG(header)));
+
+ bind(fast);
+ shrq(dst, markWord::klass_shift);
+ }
+ #endif
+
+ void MacroAssembler::load_klass(Register dst, Register src, Register tmp, bool null_check_src) {
assert_different_registers(src, tmp);
assert_different_registers(dst, tmp);
+ if (null_check_src) {
+ if (UseCompactObjectHeaders) {
+ null_check(src, oopDesc::mark_offset_in_bytes());
+ } else {
+ null_check(src, oopDesc::klass_offset_in_bytes());
+ }
+ }
#ifdef _LP64
if (UseCompressedClassPointers) {
! load_nklass(dst, src);
decode_klass_not_null(dst, tmp);
} else
#endif
movptr(dst, Address(src, oopDesc::klass_offset_in_bytes()));
}
load_klass(dst, src, tmp);
movptr(dst, Address(dst, Klass::prototype_header_offset()));
}
void MacroAssembler::store_klass(Register dst, Register src, Register tmp) {
assert_different_registers(src, tmp);
assert_different_registers(dst, tmp);
#ifdef _LP64
if (UseCompressedClassPointers) {
encode_klass_not_null(src, tmp);
movl(Address(dst, oopDesc::klass_offset_in_bytes()), src);
} else
#endif
! movptr(Address(dst, oopDesc::klass_offset_in_bytes()), src);
}
void MacroAssembler::access_load_at(BasicType type, DecoratorSet decorators, Register dst, Address src,
Register tmp1, Register thread_tmp) {
BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
load_klass(dst, src, tmp);
movptr(dst, Address(dst, Klass::prototype_header_offset()));
}
void MacroAssembler::store_klass(Register dst, Register src, Register tmp) {
+ assert(!UseCompactObjectHeaders, "not with compact headers");
assert_different_registers(src, tmp);
assert_different_registers(dst, tmp);
#ifdef _LP64
if (UseCompressedClassPointers) {
encode_klass_not_null(src, tmp);
movl(Address(dst, oopDesc::klass_offset_in_bytes()), src);
} else
#endif
! movptr(Address(dst, oopDesc::klass_offset_in_bytes()), src);
+ }
+
+ void MacroAssembler::cmp_klass(Register klass, Register obj, Register tmp) {
+ #ifdef _LP64
+ if (UseCompactObjectHeaders) {
+ // NOTE: We need to deal with possible ObjectMonitor in object header.
+ // Eventually we might be able to do simple movl & cmpl like in
+ // the CCP path below.
+ load_nklass(tmp, obj);
+ cmpl(klass, tmp);
+ } else if (UseCompressedClassPointers) {
+ cmpl(klass, Address(obj, oopDesc::klass_offset_in_bytes()));
+ } else
+ #endif
+ {
+ cmpptr(klass, Address(obj, oopDesc::klass_offset_in_bytes()));
+ }
+ }
+
+ void MacroAssembler::cmp_klass(Register src, Register dst, Register tmp1, Register tmp2) {
+ #ifdef _LP64
+ if (UseCompactObjectHeaders) {
+ // NOTE: We need to deal with possible ObjectMonitor in object header.
+ // Eventually we might be able to do simple movl & cmpl like in
+ // the CCP path below.
+ assert(tmp2 != noreg, "need tmp2");
+ assert_different_registers(src, dst, tmp1, tmp2);
+ load_nklass(tmp1, src);
+ load_nklass(tmp2, dst);
+ cmpl(tmp1, tmp2);
+ } else if (UseCompressedClassPointers) {
+ movl(tmp1, Address(src, oopDesc::klass_offset_in_bytes()));
+ cmpl(tmp1, Address(dst, oopDesc::klass_offset_in_bytes()));
+ } else
+ #endif
+ {
+ movptr(tmp1, Address(src, oopDesc::klass_offset_in_bytes()));
+ cmpptr(tmp1, Address(dst, oopDesc::klass_offset_in_bytes()));
+ }
}
void MacroAssembler::access_load_at(BasicType type, DecoratorSet decorators, Register dst, Address src,
Register tmp1, Register thread_tmp) {
BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
pop(rax);
}
}
#endif // !WIN32 || _LP64
+
+ // Implements lightweight-locking.
+ //
+ // obj: the object to be locked
+ // reg_rax: rax
+ // thread: the thread which attempts to lock obj
+ // tmp: a temporary register
+ void MacroAssembler::lightweight_lock(Register obj, Register reg_rax, Register thread, Register tmp, Label& slow) {
+ assert(reg_rax == rax, "");
+ assert_different_registers(obj, reg_rax, thread, tmp);
+
+ Label push;
+ const Register top = tmp;
+
+ // Preload the markWord. It is important that this is the first
+ // instruction emitted as it is part of C1's null check semantics.
+ movptr(reg_rax, Address(obj, oopDesc::mark_offset_in_bytes()));
+
+ // Load top.
+ movl(top, Address(thread, JavaThread::lock_stack_top_offset()));
+
+ // Check if the lock-stack is full.
+ cmpl(top, LockStack::end_offset());
+ jcc(Assembler::greaterEqual, slow);
+
+ // Check for recursion.
+ cmpptr(obj, Address(thread, top, Address::times_1, -oopSize));
+ jcc(Assembler::equal, push);
+
+ // Check header for monitor (0b10).
+ testptr(reg_rax, markWord::monitor_value);
+ jcc(Assembler::notZero, slow);
+
+ // Try to lock. Transition lock bits 0b01 => 0b00
+ movptr(tmp, reg_rax);
+ andptr(tmp, ~(int32_t)markWord::unlocked_value);
+ orptr(reg_rax, markWord::unlocked_value);
+ lock(); cmpxchgptr(tmp, Address(obj, oopDesc::mark_offset_in_bytes()));
+ jcc(Assembler::notEqual, slow);
+
+ // Restore top, CAS clobbers register.
+ movl(top, Address(thread, JavaThread::lock_stack_top_offset()));
+
+ bind(push);
+ // After successful lock, push object on lock-stack.
+ movptr(Address(thread, top), obj);
+ incrementl(top, oopSize);
+ movl(Address(thread, JavaThread::lock_stack_top_offset()), top);
+ }
+
+ // Implements lightweight-unlocking.
+ //
+ // obj: the object to be unlocked
+ // reg_rax: rax
+ // thread: the thread
+ // tmp: a temporary register
+ //
+ // x86_32 Note: reg_rax and thread may alias each other due to limited register
+ // availiability.
+ void MacroAssembler::lightweight_unlock(Register obj, Register reg_rax, Register thread, Register tmp, Label& slow) {
+ assert(reg_rax == rax, "");
+ assert_different_registers(obj, reg_rax, tmp);
+ LP64_ONLY(assert_different_registers(obj, reg_rax, thread, tmp);)
+
+ Label unlocked, push_and_slow;
+ const Register top = tmp;
+
+ // Check if obj is top of lock-stack.
+ movl(top, Address(thread, JavaThread::lock_stack_top_offset()));
+ cmpptr(obj, Address(thread, top, Address::times_1, -oopSize));
+ jcc(Assembler::notEqual, slow);
+
+ // Pop lock-stack.
+ DEBUG_ONLY(movptr(Address(thread, top, Address::times_1, -oopSize), 0);)
+ subl(Address(thread, JavaThread::lock_stack_top_offset()), oopSize);
+
+ // Check if recursive.
+ cmpptr(obj, Address(thread, top, Address::times_1, -2 * oopSize));
+ jcc(Assembler::equal, unlocked);
+
+ // Not recursive. Check header for monitor (0b10).
+ movptr(reg_rax, Address(obj, oopDesc::mark_offset_in_bytes()));
+ testptr(reg_rax, markWord::monitor_value);
+ jcc(Assembler::notZero, push_and_slow);
+
+ #ifdef ASSERT
+ // Check header not unlocked (0b01).
+ Label not_unlocked;
+ testptr(reg_rax, markWord::unlocked_value);
+ jcc(Assembler::zero, not_unlocked);
+ stop("lightweight_unlock already unlocked");
+ bind(not_unlocked);
+ #endif
+
+ // Try to unlock. Transition lock bits 0b00 => 0b01
+ movptr(tmp, reg_rax);
+ orptr(tmp, markWord::unlocked_value);
+ lock(); cmpxchgptr(tmp, Address(obj, oopDesc::mark_offset_in_bytes()));
+ jcc(Assembler::equal, unlocked);
+
+ bind(push_and_slow);
+ // Restore lock-stack and handle the unlock in runtime.
+ if (thread == reg_rax) {
+ // On x86_32 we may lose the thread.
+ get_thread(thread);
+ }
+ #ifdef ASSERT
+ movl(top, Address(thread, JavaThread::lock_stack_top_offset()));
+ movptr(Address(thread, top), obj);
+ #endif
+ addl(Address(thread, JavaThread::lock_stack_top_offset()), oopSize);
+ jmp(slow);
+
+ bind(unlocked);
+ }
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