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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/51752] trans-mem: publication safety violated Date: Thu, 09 Feb 2012 16:44:00 -0000 [thread overview] Message-ID: <bug-51752-4-uJixf5Q61g@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-51752-4@http.gcc.gnu.org/bugzilla/> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51752 --- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-02-09 16:43:40 UTC --- But isn't with __transaction_atomic { for (i = 0; i < 10; i++) if (x[i]) x[i] += data; } and __transaction_atomic { x[9] = 1; } occuring concurrently the loop transaction terminated? Thus, __transaction_atomic { tem = data; for (i = 0; i < 10; i++) if (x[i]) x[i] += tem; } equivalent? We don't hoist out of the transaction region (well, as far as I can see - the transaction region seems to be specified in a very weak way, without virtual operands or any IL barrier or such). <bb 2>: # .MEM_2 = VDEF <.MEM_1(D)> data = 23; __transaction_atomic // SUBCODE=[ GTMA_HAVE_STORE ] <bb 3>: # .MEM_3 = VDEF <.MEM_2> x[9] = 1; # .MEM_4 = VDEF <.MEM_3> __builtin__ITM_commitTransaction (); <bb 4>: # VUSE <.MEM_4> return; the __transaction_atomic // SUBCODE=[ GTMA_HAVE_STORE ] statement looks like an overly optimistic way to start a transaction in my quick view.
next prev parent reply other threads:[~2012-02-09 16:44 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top 2012-01-04 14:18 [Bug middle-end/51752] New: " torvald at gcc dot gnu.org 2012-01-04 19:18 ` [Bug middle-end/51752] " torvald at gcc dot gnu.org 2012-01-05 14:30 ` aldyh at gcc dot gnu.org 2012-01-06 14:03 ` torvald at gcc dot gnu.org 2012-02-09 16:24 ` aldyh at gcc dot gnu.org 2012-02-09 16:44 ` rguenth at gcc dot gnu.org [this message] 2012-02-09 17:40 ` rth at gcc dot gnu.org 2012-02-09 18:41 ` torvald at gcc dot gnu.org 2012-02-28 20:10 ` aldyh at gcc dot gnu.org 2012-03-16 19:15 ` aldyh at gcc dot gnu.org
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