From patchwork Tue Nov 23 17:22:11 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: sched-deps.c deps->last_pending_memory_flush fix (PR rtl-optimization/46614) Date: Tue, 23 Nov 2010 07:22:11 -0000 From: Jakub Jelinek X-Patchwork-Id: 72704 Message-Id: <20101123172211.GT29412@tyan-ft48-01.lab.bos.redhat.com> To: Jeff Law , Vladimir Makarov Cc: gcc-patches@gcc.gnu.org Hi! As mentioned in the PR, the testcase is miscompiled, because both sched_analyze_insn and sched_analyze_2 assume that all JUMP_INSNs in the deps->last_pending_memory_flush list were added there in if (deps->pending_flush_length++ > MAX_PENDING_LIST_LENGTH) flush_pending_lists (deps, insn, true, true); else deps->last_pending_memory_flush = alloc_INSN_LIST (insn, deps->last_pending_memory_flush); <==== here and thus handles them as jumps. But, a JUMP_INSN may be added there also through flush_pending_lists, be it in the above listed call or in another spot, and at that point the JUMP_INSN doesn't stand solely for itself, but also for all memory stores etc. on which that insn depends. And such a JUMP_INSN should be handled like all non-JUMP_INSN insns on the flush last_pending_memory_flush list. Fixed by instead remembering if a JUMP_INSN stands only for itself and nothing else in the deps->last_pending_memory_flush list (such jumps have REG_NOTE_KIND set to REG_DEP_ANTI, could be anything but REG_DEP_TRUE which is the default and used for additions to the list from flush_pending_lists) and using REG_NOTE_KIND instead of JUMP_P checks in the two places which care about it. Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? 2010-11-23 Jakub Jelinek PR rtl-optimization/46614 * sched-deps.c (deps_analyze_insn): Mark JUMP_INSNs in last_pending_memory_flush that weren't added through flush_pending_lists with REG_DEP_ANTI. (sched_analyze_2, sched_analyze_insn): Check REG_NOTE_KIND on INSN_LIST instead of JUMP_P check on its operand. * sched-rgn.c (concat_INSN_LIST): Copy over REG_NOTE_KIND. * gcc.dg/pr46614.c: New test. Jakub --- gcc/sched-deps.c.jj 2010-11-01 09:07:23.000000000 +0100 +++ gcc/sched-deps.c 2010-11-23 15:59:44.000000000 +0100 @@ -2484,7 +2484,7 @@ sched_analyze_2 (struct deps_desc *deps, for (u = deps->last_pending_memory_flush; u; u = XEXP (u, 1)) { - if (! JUMP_P (XEXP (u, 0))) + if (REG_NOTE_KIND (u) != REG_DEP_ANTI) add_dependence (insn, XEXP (u, 0), REG_DEP_ANTI); else if (deps_may_trap_p (x)) { @@ -2796,7 +2796,7 @@ sched_analyze_insn (struct deps_desc *de REG_DEP_ANTI); for (u = deps->last_pending_memory_flush; u; u = XEXP (u, 1)) - if (! JUMP_P (XEXP (u, 0)) + if (REG_NOTE_KIND (u) != REG_DEP_ANTI || !sel_sched_p ()) add_dependence (insn, XEXP (u, 0), REG_DEP_ANTI); @@ -3242,8 +3242,12 @@ deps_analyze_insn (struct deps_desc *dep if (deps->pending_flush_length++ > MAX_PENDING_LIST_LENGTH) flush_pending_lists (deps, insn, true, true); else - deps->last_pending_memory_flush - = alloc_INSN_LIST (insn, deps->last_pending_memory_flush); + { + deps->last_pending_memory_flush + = alloc_INSN_LIST (insn, deps->last_pending_memory_flush); + PUT_REG_NOTE_KIND (deps->last_pending_memory_flush, + REG_DEP_ANTI); + } } sched_analyze_insn (deps, PATTERN (insn), insn); --- gcc/sched-rgn.c.jj 2010-11-01 09:07:24.000000000 +0100 +++ gcc/sched-rgn.c 2010-11-23 16:00:29.000000000 +0100 @@ -2574,7 +2574,10 @@ concat_INSN_LIST (rtx copy, rtx old) { rtx new_rtx = old; for (; copy ; copy = XEXP (copy, 1)) - new_rtx = alloc_INSN_LIST (XEXP (copy, 0), new_rtx); + { + new_rtx = alloc_INSN_LIST (XEXP (copy, 0), new_rtx); + PUT_REG_NOTE_KIND (new_rtx, REG_NOTE_KIND (copy)); + } return new_rtx; } --- gcc/testsuite/gcc.dg/pr46614.c.jj 2010-11-23 16:06:07.000000000 +0100 +++ gcc/testsuite/gcc.dg/pr46614.c 2010-11-23 16:05:44.000000000 +0100 @@ -0,0 +1,56 @@ +/* PR rtl-optimization/46614 */ +/* { dg-do run } */ +/* { dg-options "-O -fno-rename-registers -fsched2-use-superblocks -fschedule-insns2 -funroll-loops" } */ + +extern void abort (void); + +struct S +{ + unsigned char a; + unsigned char b; + unsigned int c; + unsigned int e; + unsigned char f; + unsigned int g; +}; + +void bar (struct S *x) +{ + int i; + struct S *p = x; + struct S r[16]; + unsigned j; + for (i = 0; i < 16; i++) + { + r[i].c = p->b + p->c; + j = p->c + p->f; + r[i].a = j + p->b; + r[i].f = p->f + p->e; + r[i].g = p->b + p->c; + } + for (i = 0; i < 16; i++) + { + if (r[i].c != x[i].b + x[i].c + || r[i].a != x[i].c + x[i].f + x[i].b + || r[i].f != x[i].f + x[i].e + || r[i].g != x[i].b + x[i].c) + abort (); + } + for (i = 0; i < 16; i++) + { + r[i].b = p->c; + if (r[i].b != x[i].c) + abort (); + } +} + +int +main () +{ + int i; + struct S x[16]; + for (i = 0; i < 16; i++) + x[i].b = x[i].c = x[i].e = x[i].f = 5; + bar (x); + return 0; +}