--- a/hotspot/src/share/vm/c1/c1_Runtime1.cpp Tue Jan 28 15:05:46 2014 +0100
+++ b/hotspot/src/share/vm/c1/c1_Runtime1.cpp Mon Mar 03 15:54:45 2014 +0400
@@ -809,11 +809,10 @@
int bci = vfst.bci();
Bytecodes::Code code = caller_method()->java_code_at(bci);
-#ifndef PRODUCT
// this is used by assertions in the access_field_patching_id
BasicType patch_field_type = T_ILLEGAL;
-#endif // PRODUCT
bool deoptimize_for_volatile = false;
+ bool deoptimize_for_atomic = false;
int patch_field_offset = -1;
KlassHandle init_klass(THREAD, NULL); // klass needed by load_klass_patching code
KlassHandle load_klass(THREAD, NULL); // klass needed by load_klass_patching code
@@ -839,11 +838,24 @@
// is the path for patching field offsets. load_klass is only
// used for patching references to oops which don't need special
// handling in the volatile case.
+
deoptimize_for_volatile = result.access_flags().is_volatile();
-#ifndef PRODUCT
+ // If we are patching a field which should be atomic, then
+ // the generated code is not correct either, force deoptimizing.
+ // We need to only cover T_LONG and T_DOUBLE fields, as we can
+ // break access atomicity only for them.
+
+ // Strictly speaking, the deoptimizaation on 64-bit platforms
+ // is unnecessary, and T_LONG stores on 32-bit platforms need
+ // to be handled by special patching code when AlwaysAtomicAccesses
+ // becomes product feature. At this point, we are still going
+ // for the deoptimization for consistency against volatile
+ // accesses.
+
patch_field_type = result.field_type();
-#endif
+ deoptimize_for_atomic = (AlwaysAtomicAccesses && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG));
+
} else if (load_klass_or_mirror_patch_id) {
Klass* k = NULL;
switch (code) {
@@ -918,13 +930,19 @@
ShouldNotReachHere();
}
- if (deoptimize_for_volatile) {
- // At compile time we assumed the field wasn't volatile but after
- // loading it turns out it was volatile so we have to throw the
+ if (deoptimize_for_volatile || deoptimize_for_atomic) {
+ // At compile time we assumed the field wasn't volatile/atomic but after
+ // loading it turns out it was volatile/atomic so we have to throw the
// compiled code out and let it be regenerated.
if (TracePatching) {
- tty->print_cr("Deoptimizing for patching volatile field reference");
+ if (deoptimize_for_volatile) {
+ tty->print_cr("Deoptimizing for patching volatile field reference");
+ }
+ if (deoptimize_for_atomic) {
+ tty->print_cr("Deoptimizing for patching atomic field reference");
+ }
}
+
// It's possible the nmethod was invalidated in the last
// safepoint, but if it's still alive then make it not_entrant.
nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());