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From: Bart V. A. <bar...@gm...> - 2008-03-11 20:36:42
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On Tue, Mar 11, 2008 at 12:59 PM, Julian Seward <js...@ac...> wrote: > > > view of Helgrind and DRD. Can you explain the purpose of the libgomp > > patch ? > > Without that patch, the libgomp barrier routine has inter thread > dependencies controlled by the value of a shared variable. Neither > drd nor helgrind will see those. The patch adds an extra semaphore > which generates just enough new inter-thread dependencies via > post/wait events, that the overall hb graph for the barrier as a > whole has correct dependencies. I investigated this by dumping the hb > graph to a file and using xvcg to look at it. I found another way to handle libgomp barriers: by intercepting them. Unfortunately this only works when libgomp.so contains debug information. Bart. |