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6916623: Align object to 16 bytes to use Compressed Oops with java heap up to 64Gb

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Added new product ObjectAlignmentInBytes flag to control object alignment.

Reviewed-by: twisti, ysr, iveresov
This commit is contained in:
Vladimir Kozlov 2010-05-27 18:01:56 -07:00
parent 05b4f2e796
commit cc18a50e59
29 changed files with 222 additions and 136 deletions
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17
hotspot/src/share/vm/oops/oop.inline.hpp
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@ -146,8 +146,13 @@ inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
// offset from the heap base. Saving the check for null can save instructions
// in inner GC loops so these are separated.
inline bool check_obj_alignment(oop obj) {
return (intptr_t)obj % MinObjAlignmentInBytes == 0;
}
inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
assert(!is_null(v), "oop value can never be zero");
assert(check_obj_alignment(v), "Address not aligned");
assert(Universe::heap()->is_in_reserved(v), "Address not in heap");
address base = Universe::narrow_oop_base();
int shift = Universe::narrow_oop_shift();
@ -167,7 +172,9 @@ inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
assert(!is_null(v), "narrow oop value can never be zero");
address base = Universe::narrow_oop_base();
int shift = Universe::narrow_oop_shift();
return (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
assert(check_obj_alignment(result), "Address not aligned");
return result;
}
inline oop oopDesc::decode_heap_oop(narrowOop v) {
@ -522,10 +529,6 @@ inline bool oopDesc::has_bias_pattern() const {
return mark()->has_bias_pattern();
}
inline bool check_obj_alignment(oop obj) {
return (intptr_t)obj % MinObjAlignmentInBytes == 0;
}
// used only for asserts
inline bool oopDesc::is_oop(bool ignore_mark_word) const {
@ -600,6 +603,8 @@ inline bool oopDesc::is_forwarded() const {
// Used by scavengers
inline void oopDesc::forward_to(oop p) {
assert(check_obj_alignment(p),
"forwarding to something not aligned");
assert(Universe::heap()->is_in_reserved(p),
"forwarding to something not in heap");
markOop m = markOopDesc::encode_pointer_as_mark(p);
@ -609,6 +614,8 @@ inline void oopDesc::forward_to(oop p) {
// Used by parallel scavengers
inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
assert(check_obj_alignment(p),
"forwarding to something not aligned");
assert(Universe::heap()->is_in_reserved(p),
"forwarding to something not in heap");
markOop m = markOopDesc::encode_pointer_as_mark(p);