Mercurial > hg > openjdk > hsx17
changeset 1335:d53d91cb378c
6953058: G1: A bigapp crashes with SIGSEGV in compiled code
Summary: In C2's G1 post write barrier, the loads of the buffer and index fields from the DirtyCardQueue structure may be moved across a safepoint. Use the current value of "control" in the C2 IR to limit how far these loads can move.
Reviewed-by: never, iveresov, kvn
| author | johnc |
|---|---|
| date | Mon, 07 Jun 2010 17:46:04 -0700 |
| parents | 193a468093fa |
| children | e835ff93bcc1 |
| files | src/share/vm/opto/graphKit.cpp |
| diffstat | 1 files changed, 4 insertions(+), 5 deletions(-) [+] |
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--- a/src/share/vm/opto/graphKit.cpp Wed May 26 00:30:39 2010 -0700 +++ b/src/share/vm/opto/graphKit.cpp Mon Jun 07 17:46:04 2010 -0700 @@ -3492,7 +3492,6 @@ Node* tls = __ thread(); // ThreadLocalStorage - Node* no_ctrl = NULL; Node* no_base = __ top(); float likely = PROB_LIKELY(0.999); float unlikely = PROB_UNLIKELY(0.999); @@ -3516,10 +3515,10 @@ Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset)); // Now some values - - Node* index = __ load(no_ctrl, index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw); - Node* buffer = __ load(no_ctrl, buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw); - + // Use ctrl to avoid hoisting these values past a safepoint, which could + // potentially reset these fields in the JavaThread. + Node* index = __ load(__ ctrl(), index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw); + Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw); // Convert the store obj pointer to an int prior to doing math on it // Must use ctrl to prevent "integerized oop" existing across safepoint