public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
* [Bug target/108484] New: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 @ 2023-01-20 18:41 jsm28 at gcc dot gnu.org 2023-01-21 22:39 ` [Bug target/108484] " law at gcc dot gnu.org ` (7 more replies) 0 siblings, 8 replies; 9+ messages in thread From: jsm28 at gcc dot gnu.org @ 2023-01-20 18:41 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108484 Bug ID: 108484 Summary: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 Product: gcc Version: 13.0 Status: UNCONFIRMED Keywords: ice-on-valid-code Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: jsm28 at gcc dot gnu.org CC: aoliva at gcc dot gnu.org Target Milestone: --- Target: ia64*-*-* Created attachment 54319 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=54319&action=edit preprocessed source Compile the attached file (from glibc) with -g -O2 for ia64-linux-gnu. This produces the following ICE: during RTL pass: mach In file included from ../sysdeps/ia64/unwind-resume.c:18: ../sysdeps/generic/unwind-resume.c: In function '_Unwind_Resume': ../sysdeps/generic/unwind-resume.c:38:1: internal compiler error: in cselib_subst_to_values, at cselib.cc:2148 0x5fd409 cselib_subst_to_values(rtx_def*, machine_mode) /scratch/jmyers/glibc/many13/src/gcc/gcc/cselib.cc:2148 0x98c873 cselib_subst_to_values(rtx_def*, machine_mode) /scratch/jmyers/glibc/many13/src/gcc/gcc/cselib.cc:2193 0x98f761 cselib_subst_to_values_from_insn(rtx_def*, machine_mode, rtx_insn*) /scratch/jmyers/glibc/many13/src/gcc/gcc/cselib.cc:2264 0x18172aa add_insn_mem_dependence /scratch/jmyers/glibc/many13/src/gcc/gcc/sched-deps.cc:1741 0x181b230 sched_analyze_2 /scratch/jmyers/glibc/many13/src/gcc/gcc/sched-deps.cc:2688 0x181b267 sched_analyze_2 /scratch/jmyers/glibc/many13/src/gcc/gcc/sched-deps.cc:2806 0x181b9eb sched_analyze_insn /scratch/jmyers/glibc/many13/src/gcc/gcc/sched-deps.cc:2960 0x181ddb0 deps_analyze_insn(deps_desc*, rtx_insn*) /scratch/jmyers/glibc/many13/src/gcc/gcc/sched-deps.cc:3683 0x181e40e sched_analyze(deps_desc*, rtx_insn*, rtx_insn*) /scratch/jmyers/glibc/many13/src/gcc/gcc/sched-deps.cc:3836 0x1821870 schedule_ebb(rtx_insn*, rtx_insn*, bool) /scratch/jmyers/glibc/many13/src/gcc/gcc/sched-ebb.cc:505 0x1821da2 schedule_ebbs() /scratch/jmyers/glibc/many13/src/gcc/gcc/sched-ebb.cc:655 0x11b3346 ia64_reorg /scratch/jmyers/glibc/many13/src/gcc/gcc/config/ia64/ia64.cc:9862 0xdb527d execute /scratch/jmyers/glibc/many13/src/gcc/gcc/reorg.cc:3927 Please submit a full bug report, with preprocessed source (by using -freport-bug). Please include the complete backtrace with any bug report. See <https://gcc.gnu.org/bugs/> for instructions. Introduced by g:3c99493bf39a7fef9213e6f5af94b78bb15fcfdc commit 3c99493bf39a7fef9213e6f5af94b78bb15fcfdc Author: Alexandre Oliva <oliva@adacore.com> Date: Thu Jan 19 01:09:15 2023 -0300 [PR106746] drop cselib addr lookup in debug insn mem The testcase used to get scheduled differently depending on the presence of debug insns with MEMs. It's not clear to me why those MEMs affected scheduling, but the cselib pre-canonicalization of the MEM address is not used at all when analyzing debug insns, so the memory allocation and lookup are pure waste. Somehow, avoiding that waste fixes the problem, or makes it go latent. for gcc/ChangeLog PR debug/106746 * sched-deps.cc (sched_analyze_2): Skip cselib address lookup within debug insns. for gcc/testsuite/ChangeLog PR debug/106746 * gcc.target/i386/pr106746.c: New. ^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug target/108484] [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 2023-01-20 18:41 [Bug target/108484] New: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 jsm28 at gcc dot gnu.org @ 2023-01-21 22:39 ` law at gcc dot gnu.org 2023-01-21 22:40 ` law at gcc dot gnu.org ` (6 subsequent siblings) 7 siblings, 0 replies; 9+ messages in thread From: law at gcc dot gnu.org @ 2023-01-21 22:39 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108484 Jeffrey A. Law <law at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |law at gcc dot gnu.org --- Comment #1 from Jeffrey A. Law <law at gcc dot gnu.org> --- Created attachment 54325 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=54325&action=edit Testcase for c6x ^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug target/108484] [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 2023-01-20 18:41 [Bug target/108484] New: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 jsm28 at gcc dot gnu.org 2023-01-21 22:39 ` [Bug target/108484] " law at gcc dot gnu.org @ 2023-01-21 22:40 ` law at gcc dot gnu.org 2023-01-23 7:41 ` rguenth at gcc dot gnu.org ` (5 subsequent siblings) 7 siblings, 0 replies; 9+ messages in thread From: law at gcc dot gnu.org @ 2023-01-21 22:40 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108484 Jeffrey A. Law <law at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Last reconfirmed| |2023-01-21 Ever confirmed|0 |1 Status|UNCONFIRMED |NEW --- Comment #2 from Jeffrey A. Law <law at gcc dot gnu.org> --- I'm seeing this for c6x as well building libgcc. Testcase attached, compile with -O2 -g. ^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug target/108484] [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 2023-01-20 18:41 [Bug target/108484] New: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 jsm28 at gcc dot gnu.org 2023-01-21 22:39 ` [Bug target/108484] " law at gcc dot gnu.org 2023-01-21 22:40 ` law at gcc dot gnu.org @ 2023-01-23 7:41 ` rguenth at gcc dot gnu.org 2023-01-30 17:50 ` jakub at gcc dot gnu.org ` (4 subsequent siblings) 7 siblings, 0 replies; 9+ messages in thread From: rguenth at gcc dot gnu.org @ 2023-01-23 7:41 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108484 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|--- |13.0 ^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug target/108484] [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 2023-01-20 18:41 [Bug target/108484] New: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 jsm28 at gcc dot gnu.org ` (2 preceding siblings ...) 2023-01-23 7:41 ` rguenth at gcc dot gnu.org @ 2023-01-30 17:50 ` jakub at gcc dot gnu.org 2023-02-01 16:36 ` jakub at gcc dot gnu.org ` (3 subsequent siblings) 7 siblings, 0 replies; 9+ messages in thread From: jakub at gcc dot gnu.org @ 2023-01-30 17:50 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108484 Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jakub at gcc dot gnu.org --- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> --- See PR108463 and https://gcc.gnu.org/pipermail/gcc-patches/2023-January/610778.html ^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug target/108484] [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 2023-01-20 18:41 [Bug target/108484] New: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 jsm28 at gcc dot gnu.org ` (3 preceding siblings ...) 2023-01-30 17:50 ` jakub at gcc dot gnu.org @ 2023-02-01 16:36 ` jakub at gcc dot gnu.org 2023-02-02 12:56 ` cvs-commit at gcc dot gnu.org ` (2 subsequent siblings) 7 siblings, 0 replies; 9+ messages in thread From: jakub at gcc dot gnu.org @ 2023-02-01 16:36 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108484 Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- URL| |https://gcc.gnu.org/piperma | |il/gcc-patches/2023-January | |/610778.html --- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> --- I've just verified the https://gcc.gnu.org/pipermail/gcc-patches/2023-January/610778.html patch fixes both the #c0 ICE on ia64-linux and #c1 ICE on tic6x-uclinux (and without it both ICE for me). ^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug target/108484] [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 2023-01-20 18:41 [Bug target/108484] New: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 jsm28 at gcc dot gnu.org ` (4 preceding siblings ...) 2023-02-01 16:36 ` jakub at gcc dot gnu.org @ 2023-02-02 12:56 ` cvs-commit at gcc dot gnu.org 2023-02-02 12:57 ` jakub at gcc dot gnu.org 2023-02-02 12:59 ` sam at gentoo dot org 7 siblings, 0 replies; 9+ messages in thread From: cvs-commit at gcc dot gnu.org @ 2023-02-02 12:56 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108484 --- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>: https://gcc.gnu.org/g:465a9c51e7d5bafa7a81195b5af20f2a54f22210 commit r13-5652-g465a9c51e7d5bafa7a81195b5af20f2a54f22210 Author: Jakub Jelinek <jakub@redhat.com> Date: Thu Feb 2 13:52:45 2023 +0100 sched-deps, cselib: Fix up some -fcompare-debug issues and regressions [PR108463] On Sat, Jan 14, 2023 at 08:26:00AM -0300, Alexandre Oliva via Gcc-patches wrote: > The testcase used to get scheduled differently depending on the > presence of debug insns with MEMs. It's not clear to me why those > MEMs affected scheduling, but the cselib pre-canonicalization of the > MEM address is not used at all when analyzing debug insns, so the > memory allocation and lookup are pure waste. Somehow, avoiding that > waste fixes the problem, or makes it go latent. Unfortunately, this patch breaks the following testcase. The code in sched_analyze_2 did 2 things: 1) cselib_lookup_from_insn 2) shallow_copy_rtx + cselib_subst_to_values_from_insn Now, 1) is precondition of 2), we can only subst the VALUEs if we have actually looked the address up, but as can be seen on that testcase, we are relying on at least the 1) to be done because we subst the values later on even on DEBUG_INSNs and actually use those when needed. cselib_subst_to_values_from_insn mostly just replaces stuff in the returned rtx, except for: /* This used to happen for autoincrements, but we deal with them properly now. Remove the if stmt for the next release. */ if (! e) { /* Assign a value that doesn't match any other. */ e = new_cselib_val (next_uid, GET_MODE (x), x); } which is like that since 2011, I hope it is never reachable and we should in stage1 replace that with gcc_assert or just remove (then it will segfault on following return e->val_rtx; ). So, I (as done in the patch below) reinstalled the 1) and not 2) for DEBUG_INSNs. This fixed the new testcase, but broke again the PR106746 testcases. I've spent a day debugging that and found the problem is that as documented in a large comment in cselib.cc above n_useless_values variable definition, we spend quite a few effort on making sure that VALUEs created on DEBUG_INSNs don't affect the cselib decisions for non-DEBUG_INSNs such as pruning of useless values etc., but if a VALUE created that way is then looked up/needed from non-DEBUG_INSNs, we promote it to non-debug. The reason for -fcompare-debug failure is that there is one large DEBUG_INSN with 16 MEMs in it mostly with addresses that so far didn't appear in the IL otherwise. Later on, we see an instruction storing into MEM destination and invalidate that MEM. Unfortunately, there is a bug caused by the introduction of SP_DERIVED_VALUE_P where alias.cc isn't able to disambiguate MEMs with sp + optional offset in address vs. MEMs with address being a VALUE having SP_DERIVED_VALUE_P + constant (or the SP_DERIVED_VALUE_P itself), which ought to be possible when REG_VALUES (REGNO (stack_pointer_rtx)) has SP_DERIVED_VALUE_P + constant location. Not sure if I should try to fix that in stage4 or defer for stage1. Anyway, the cselib_invalidate_mem call because of this invalidates basically all MEMs with the exception of 5 which have MEM_EXPRs that guarantee non-aliasing with the sp based store. Unfortunately, n_useless_values which in my understanding should be always the same between -g and -g0 compilations diverges, has 3 more useless values for -g. Now, these were initially VALUEs created for DEBUG_INSN lookups. As I said, cselib.cc has code to promote such VALUEs (well, their location elements) to non-debug if they are looked up from non-DEBUG_INSNs. The problem is that when looking some completely unrelated MEM from a non-DEBUG_INSN we run into a hash collision and so call cselib_hasher::equal to check if the unrelated MEM is equal to the one from DEBUG_INSN only element. The equal static member function calls rtx_equal_for_cselib_1 and if that returns true, promotes the location to non-DEBUG, otherwise returns false. So far so good. But rtx_equal_for_cselib_1 internally performs various other cselib lookups, all done with the non-DEBUG_INSN cselib_current_insn, so they all promote to non-debug. And that is wrong, because if it was -g0 compilation, such hashtable entry wouldn't be there at all (or would be but wouldn't contain that locs element), so with -g0 we wouldn't call that rtx_equal_for_cselib_1 at all. So, I think we need to pretend that such lookup which only happens with -g and not -g0 actually comes from some DEBUG_INSN (note, the lookups rtx_equal_for_cselib_1 does are always with create = 0). The cselib.cc part of the patch does that. BTW, I'm not really sure how: if (num_mems < param_max_cselib_memory_locations && ! canon_anti_dependence (x, false, mem_rtx, GET_MODE (mem_rtx), mem_addr)) { has_mem = true; num_mems++; p = &(*p)->next; continue; } num_mems cap can actually work correctly for -fcompare-debug, I'd think we would need to differentiate between num_debug_mems and num_mems depending on if setting_insn is non-NULL DEBUG_INSN or not. That was one of my suspicions on this testcase, but the number of MEMs was small enough for the param in either case (especially because of the above mentioned missed non-aliasings). But as implemented, I think if we have tons of non-aliased MEMs from DEBUG_INSN setting_insns, we could unchain lots more non-DEBUG MEMs with -g than with -g0. 2023-02-02 Jakub Jelinek <jakub@redhat.com> PR debug/106746 PR rtl-optimization/108463 PR target/108484 * cselib.cc (cselib_current_insn): Move declaration earlier. (cselib_hasher::equal): For debug only locs, temporarily override cselib_current_insn to their l->setting_insn for the rtx_equal_for_cselib_1 call, so that unsuccessful comparisons don't promote some debug locs. * sched-deps.cc (sched_analyze_2) <case MEM>: For MEMs in DEBUG_INSNs when using cselib call cselib_lookup_from_insn on the address but don't substitute it. * gcc.dg/pr108463.c: New test. ^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug target/108484] [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 2023-01-20 18:41 [Bug target/108484] New: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 jsm28 at gcc dot gnu.org ` (5 preceding siblings ...) 2023-02-02 12:56 ` cvs-commit at gcc dot gnu.org @ 2023-02-02 12:57 ` jakub at gcc dot gnu.org 2023-02-02 12:59 ` sam at gentoo dot org 7 siblings, 0 replies; 9+ messages in thread From: jakub at gcc dot gnu.org @ 2023-02-02 12:57 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108484 Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED Resolution|--- |FIXED --- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Should be fixed now. ^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug target/108484] [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 2023-01-20 18:41 [Bug target/108484] New: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 jsm28 at gcc dot gnu.org ` (6 preceding siblings ...) 2023-02-02 12:57 ` jakub at gcc dot gnu.org @ 2023-02-02 12:59 ` sam at gentoo dot org 7 siblings, 0 replies; 9+ messages in thread From: sam at gentoo dot org @ 2023-02-02 12:59 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108484 --- Comment #7 from Sam James <sam at gentoo dot org> --- Could you add 108463 to See Also? Thanks. ^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2023-02-02 12:59 UTC | newest] Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2023-01-20 18:41 [Bug target/108484] New: [13 Regression] ICE building glibc for ia64 in cselib_subst_to_values, at cselib.cc:2148 jsm28 at gcc dot gnu.org 2023-01-21 22:39 ` [Bug target/108484] " law at gcc dot gnu.org 2023-01-21 22:40 ` law at gcc dot gnu.org 2023-01-23 7:41 ` rguenth at gcc dot gnu.org 2023-01-30 17:50 ` jakub at gcc dot gnu.org 2023-02-01 16:36 ` jakub at gcc dot gnu.org 2023-02-02 12:56 ` cvs-commit at gcc dot gnu.org 2023-02-02 12:57 ` jakub at gcc dot gnu.org 2023-02-02 12:59 ` sam at gentoo dot org
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).