Mercurial > hg > truffle
changeset 17951:6a0ad2977919
8039042: G1: Phantom zeros in cardtable
Reviewed-by: tschatzl, mgerdin
author | pliden |
---|---|
date | Tue, 20 May 2014 10:24:30 +0200 |
parents | 8a140676873f |
children | 09619752c16d |
files | src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.cpp |
diffstat | 1 files changed, 9 insertions(+), 1 deletions(-) [+] |
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--- a/src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.cpp Wed May 14 14:32:23 2014 +0200 +++ b/src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.cpp Tue May 20 10:24:30 2014 +0200 @@ -95,7 +95,15 @@ jbyte *const first = byte_for(mr.start()); jbyte *const last = byte_after(mr.last()); - memset(first, g1_young_gen, last - first); + // Below we may use an explicit loop instead of memset() because on + // certain platforms memset() can give concurrent readers phantom zeros. + if (UseMemSetInBOT) { + memset(first, g1_young_gen, last - first); + } else { + for (jbyte* i = first; i < last; i++) { + *i = g1_young_gen; + } + } } #ifndef PRODUCT