| Summary: | [4.9 Regression] ICE at -O2 and -O3 on x86_64-linux-gnu | ||
|---|---|---|---|
| Product: | gcc | Reporter: | Zhendong Su <su> |
| Component: | tree-optimization | Assignee: | Richard Biener <rguenth> |
| Status: | RESOLVED FIXED | ||
| Severity: | normal | ||
| Priority: | P2 | ||
| Version: | 6.0 | ||
| Target Milestone: | 4.9.4 | ||
| Host: | Target: | ||
| Build: | Known to work: | 5.2.0, 6.0 | |
| Known to fail: | 4.9.3, 5.1.0 | Last reconfirmed: | 2015-07-08 00:00:00 |
| Bug Depends on: | 66807 | ||
| Bug Blocks: | |||
So this means post-dominators are corrupt at then entry to DSE. Usually passes
should always release post-dominators - it seems there is at least one that fails to do that. isolate-paths in this case. Passes are not good at making sure
to release post-dom-info when they invalidate it.
The regression is due to extra checking.
Index: gcc/gimple-ssa-isolate-paths.c
===================================================================
--- gcc/gimple-ssa-isolate-paths.c (revision 225504)
+++ gcc/gimple-ssa-isolate-paths.c (working copy)
@@ -501,10 +501,10 @@ gimple_ssa_isolate_erroneous_paths (void
/* We scramble the CFG and loop structures a bit, clean up
appropriately. We really should incrementally update the
loop structures, in theory it shouldn't be that hard. */
+ free_dominance_info (CDI_POST_DOMINATORS);
if (cfg_altered)
{
free_dominance_info (CDI_DOMINATORS);
- free_dominance_info (CDI_POST_DOMINATORS);
loops_state_set (LOOPS_NEED_FIXUP);
return TODO_cleanup_cfg | TODO_update_ssa;
}
fixes it.
Author: rguenth Date: Wed Jul 8 11:47:42 2015 New Revision: 225545 URL: https://gcc.gnu.org/viewcvs?rev=225545&root=gcc&view=rev Log: 2015-07-08 Richard Biener <rguenther@suse.de> PR tree-optimization/66794 * passes.c (execute_function_todo): Assert that post-dominators are not computed. * gimple-ssa-isolate-paths.c (gimple_ssa_isolate_erroneous_paths): Free post-dominators. * gcc.dg/torture/pr66794.c: New testcase. Added: trunk/gcc/testsuite/gcc.dg/torture/pr66794.c Modified: trunk/gcc/ChangeLog trunk/gcc/gimple-ssa-isolate-paths.c trunk/gcc/passes.c trunk/gcc/testsuite/ChangeLog Fixed on trunk. The issue is latent on the branches though, possibly using broken post-dom info. Author: rguenth Date: Fri Jul 10 12:33:28 2015 New Revision: 225671 URL: https://gcc.gnu.org/viewcvs?rev=225671&root=gcc&view=rev Log: 2015-07-10 Richard Biener <rguenther@suse.de> Backport from mainline 2015-07-10 Richard Biener <rguenther@suse.de> PR tree-optimization/66823 * tree-if-conv.c (memrefs_read_or_written_unconditionally): Fix inverted predicate. * gcc.dg/vect/pr61194.c: Remove -ftree-loop-if-convert-stores which should not be necessary. XFAIL. 2015-07-08 Richard Biener <rguenther@suse.de> PR middle-end/43341 * toplev.c (compile_file): Reset maximum_field_alignment after parsing. 2015-07-08 Richard Biener <rguenther@suse.de> PR tree-optimization/66794 * gimple-ssa-isolate-paths.c (gimple_ssa_isolate_erroneous_paths): Free post-dominators. * gcc.dg/torture/pr66794.c: New testcase. Added: branches/gcc-5-branch/gcc/testsuite/gcc.dg/torture/pr66794.c Modified: branches/gcc-5-branch/gcc/ChangeLog branches/gcc-5-branch/gcc/gimple-ssa-isolate-paths.c branches/gcc-5-branch/gcc/testsuite/ChangeLog branches/gcc-5-branch/gcc/testsuite/gcc.dg/vect/pr61194.c branches/gcc-5-branch/gcc/toplev.c branches/gcc-5-branch/gcc/tree-if-conv.c Author: rguenth Date: Thu Feb 11 13:40:31 2016 New Revision: 233344 URL: https://gcc.gnu.org/viewcvs?rev=233344&root=gcc&view=rev Log: 2016-02-11 Richard Biener <rguenther@suse.de> Backport from mainline 2015-02-18 Richard Biener <rguenther@suse.de> PR tree-optimization/62217 * tree-ssa-dom.c (cprop_operand): Avoid propagating copies into BIVs. * gcc.dg/tree-ssa/cunroll-11.c: New testcase. 2015-06-18 Richard Biener <rguenther@suse.de> Backport from mainline 2015-06-03 Richard Biener <rguenther@suse.de> PR tree-optimization/66375 * tree-scalar-evolution.c (follow_ssa_edge_binary): First add to the evolution before following SSA edges. * gcc.dg/torture/pr66375.c: New testcase. 2015-06-23 Richard Biener <rguenther@suse.de> Backport from mainline 2015-06-09 Richard Biener <rguenther@suse.de> PR middle-end/66413 * tree-inline.c (insert_init_debug_bind): Unshare value. * gcc.dg/torture/pr66413.c: New testcase. 2015-07-08 Richard Biener <rguenther@suse.de> PR tree-optimization/66794 * gimple-ssa-isolate-paths.c (gimple_ssa_isolate_erroneous_paths): Free post-dominators. * gcc.dg/torture/pr66794.c: New testcase. 2015-07-10 Richard Biener <rguenther@suse.de> PR tree-optimization/66823 * tree-if-conv.c (memrefs_read_or_written_unconditionally): Fix inverted predicate. Added: branches/gcc-4_9-branch/gcc/testsuite/gcc.dg/torture/pr66375.c branches/gcc-4_9-branch/gcc/testsuite/gcc.dg/torture/pr66413.c branches/gcc-4_9-branch/gcc/testsuite/gcc.dg/torture/pr66794.c branches/gcc-4_9-branch/gcc/testsuite/gcc.dg/tree-ssa/cunroll-11.c Modified: branches/gcc-4_9-branch/gcc/ChangeLog branches/gcc-4_9-branch/gcc/gimple-ssa-isolate-paths.c branches/gcc-4_9-branch/gcc/gimple.c branches/gcc-4_9-branch/gcc/testsuite/ChangeLog branches/gcc-4_9-branch/gcc/tree-if-conv.c branches/gcc-4_9-branch/gcc/tree-inline.c branches/gcc-4_9-branch/gcc/tree-scalar-evolution.c branches/gcc-4_9-branch/gcc/tree-ssa-dom.c Fixed. |
The following code causes an ICE when compiled with the current gcc trunk at -O3 on x86_64-linux-gnu in both 32-bit and 64-bit modes. It is a regression from 5.1.x. $ gcc-trunk -v Using built-in specs. COLLECT_GCC=gcc-trunk COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-unknown-linux-gnu/6.0.0/lto-wrapper Target: x86_64-unknown-linux-gnu Configured with: ../gcc-trunk/configure --prefix=/usr/local/gcc-trunk --enable-languages=c,c++ --disable-werror --enable-multilib Thread model: posix gcc version 6.0.0 20150707 (experimental) [trunk revision 225501] (GCC) $ $ gcc-trunk -Os -c small.c small.c: In function ‘fn1’: small.c:18:10: warning: function returns address of local variable [-Wreturn-local-addr] return *c; ^ small.c:12:7: note: declared here int f, **g = &b; ^ $ gcc-5.1 -O2 -c small.c small.c: In function ‘fn1’: small.c:18:10: warning: function may return address of local variable [-Wreturn-local-addr] return *c; ^ small.c:12:7: note: declared here int f, **g = &b; ^ $ $ gcc-trunk -O2 -c small.c small.c: In function ‘fn1’: small.c:18:10: warning: function may return address of local variable [-Wreturn-local-addr] return *c; ^ small.c:12:7: note: declared here int f, **g = &b; ^ small.c:10:1: error: dominator of 4 status unknown fn1 () ^ small.c:10:1: internal compiler error: Segmentation fault 0xbb296f crash_signal ../../gcc-trunk/gcc/toplev.c:360 0x76ac43 verify_dominators(cdi_direction) ../../gcc-trunk/gcc/dominance.c:1059 0x76aed7 calculate_dominance_info(cdi_direction) ../../gcc-trunk/gcc/dominance.c:685 0xcd85e4 execute ../../gcc-trunk/gcc/tree-ssa-dse.c:404 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <http://gcc.gnu.org/bugs.html> for instructions. $ ------------------------------ int a, *b, e; static int **c = &b; struct { int f0; } d; int * fn1 () { int f, **g = &b; e = a; for (; a;) for (; d.f0; d.f0++) ; *g = &f; return *c; }