--- a/hotspot/src/cpu/x86/vm/macroAssembler_x86.cpp Thu Jun 18 10:47:34 2015 -0400
+++ b/hotspot/src/cpu/x86/vm/macroAssembler_x86.cpp Fri Jun 19 09:41:49 2015 +0200
@@ -4260,31 +4260,24 @@
//////////////////////////////////////////////////////////////////////////////////
+void MacroAssembler::store_check(Register obj, Address dst) {
+ store_check(obj);
+}
+
void MacroAssembler::store_check(Register obj) {
// Does a store check for the oop in register obj. The content of
// register obj is destroyed afterwards.
- store_check_part_1(obj);
- store_check_part_2(obj);
-}
-
-void MacroAssembler::store_check(Register obj, Address dst) {
- store_check(obj);
-}
-
-
-// split the store check operation so that other instructions can be scheduled inbetween
-void MacroAssembler::store_check_part_1(Register obj) {
+
BarrierSet* bs = Universe::heap()->barrier_set();
assert(bs->kind() == BarrierSet::CardTableModRef, "Wrong barrier set kind");
- shrptr(obj, CardTableModRefBS::card_shift);
-}
-
-void MacroAssembler::store_check_part_2(Register obj) {
- BarrierSet* bs = Universe::heap()->barrier_set();
- assert(bs->kind() == BarrierSet::CardTableModRef, "Wrong barrier set kind");
+
CardTableModRefBS* ct = barrier_set_cast<CardTableModRefBS>(bs);
assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust this code");
+ shrptr(obj, CardTableModRefBS::card_shift);
+
+ Address card_addr;
+
// The calculation for byte_map_base is as follows:
// byte_map_base = _byte_map - (uintptr_t(low_bound) >> card_shift);
// So this essentially converts an address to a displacement and it will
@@ -4292,8 +4285,7 @@
// large for a 32bit displacement.
intptr_t disp = (intptr_t) ct->byte_map_base;
if (is_simm32(disp)) {
- Address cardtable(noreg, obj, Address::times_1, disp);
- movb(cardtable, 0);
+ card_addr = Address(noreg, obj, Address::times_1, disp);
} else {
// By doing it as an ExternalAddress 'disp' could be converted to a rip-relative
// displacement and done in a single instruction given favorable mapping and a
@@ -4301,7 +4293,18 @@
// entry and that entry is not properly handled by the relocation code.
AddressLiteral cardtable((address)ct->byte_map_base, relocInfo::none);
Address index(noreg, obj, Address::times_1);
- movb(as_Address(ArrayAddress(cardtable, index)), 0);
+ card_addr = as_Address(ArrayAddress(cardtable, index));
+ }
+
+ int dirty = CardTableModRefBS::dirty_card_val();
+ if (UseCondCardMark) {
+ Label L_already_dirty;
+ cmpb(card_addr, dirty);
+ jcc(Assembler::equal, L_already_dirty);
+ movb(card_addr, dirty);
+ bind(L_already_dirty);
+ } else {
+ movb(card_addr, dirty);
}
}