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Fix PR 56077


Hello,

As found by Jakub and explained in the PR audit trail by Alexander, this patch fixes the selective scheduler merge glitch of 2008 that added the unnecessary JUMP_P check to the flush_pending_lists call. I have removed the check and expanded the binary negation for clarity.

The patch was tested on x86-64, ia64, and ppc64 to be safe. The patch should be conservatively safe at this stage as it adds more flushes and thus more dependencies to the scheduler. The original test is fixed, but I don't know how to add the test checking assembly insns order to the testsuite.

OK for trunk?

Andrey

2012-02-22  Alexander Monakov  <amonakov@ispras.ru>
	    Andrey Belevantsev  <abel@ispras.ru>

	PR middle-end/56077
	* sched-deps.c (sched_analyze_insn): When reg_pending_barrier,
	flush pending lists also on non-jumps.
Index: gcc/sched-deps.c
===================================================================
*** gcc/sched-deps.c	(revision 196136)
--- gcc/sched-deps.c	(working copy)
*************** sched_analyze_insn (struct deps_desc *de
*** 3318,3325 ****
            }
  
        /* Flush pending lists on jumps, but not on speculative checks.  */
!       if (JUMP_P (insn) && !(sel_sched_p ()
!                              && sel_insn_is_speculation_check (insn)))
  	flush_pending_lists (deps, insn, true, true);
  
        reg_pending_barrier = NOT_A_BARRIER;
--- 3318,3324 ----
            }
  
        /* Flush pending lists on jumps, but not on speculative checks.  */
!       if (!sel_sched_p () || !sel_insn_is_speculation_check (insn))
  	flush_pending_lists (deps, insn, true, true);
  
        reg_pending_barrier = NOT_A_BARRIER;

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