< prev index next > src/hotspot/cpu/x86/macroAssembler_x86.cpp
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}
// 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");
+ 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())); // 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) {
assert_different_registers(src, tmp);
assert_different_registers(dst, tmp);
#ifdef _LP64
if (UseCompressedClassPointers) {
- movl(dst, Address(src, oopDesc::klass_offset_in_bytes()));
+ load_nklass(dst, src);
decode_klass_not_null(dst, tmp);
} else
#endif
movptr(dst, Address(src, oopDesc::klass_offset_in_bytes()));
}
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);
+ 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();
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