On 10/13/2017 04:59 PM, Jeff Law wrote: > On 10/13/2017 07:02 AM, Martin Liška wrote: >> On 10/12/2017 11:54 PM, Jeff Law wrote: >>> On 10/11/2017 12:13 AM, Martin Liška wrote: >>>> 2017-10-10 Martin Liska <mli...@suse.cz> >>>> >>>> PR tree-optimization/82493 >>>> * sbitmap.c (bitmap_bit_in_range_p): Fix the implementation. >>>> (test_range_functions): New function. >>>> (sbitmap_c_tests): Likewise. >>>> * selftest-run-tests.c (selftest::run_tests): Run new tests. >>>> * selftest.h (sbitmap_c_tests): New function. >>> I went ahead and committed this along with a patch to fix the off-by-one >>> error in live_bytes_read. Bootstrapped and regression tested on x86. >>> >>> Actual patch attached for archival purposes. >>> >>> Jeff >>> >> >> Hello. >> >> I wrote a patch that adds various gcc_checking_asserts and I hit following: >> >> ./xgcc -B. >> /home/marxin/Programming/gcc/gcc/testsuite/gfortran.dg/char_result_12.f90 -c >> -O2 >> during GIMPLE pass: dse >> /home/marxin/Programming/gcc/gcc/testsuite/gfortran.dg/char_result_12.f90:7:0: >> >> program testat >> >> internal compiler error: in bitmap_check_index, at sbitmap.h:105 >> 0x1c014c1 bitmap_check_index >> ../../gcc/sbitmap.h:105 >> 0x1c01fa7 bitmap_bit_in_range_p(simple_bitmap_def const*, unsigned int, >> unsigned int) >> ../../gcc/sbitmap.c:335 >> 0x1179002 live_bytes_read >> ../../gcc/tree-ssa-dse.c:497 >> 0x117935a dse_classify_store >> ../../gcc/tree-ssa-dse.c:595 >> 0x1179947 dse_dom_walker::dse_optimize_stmt(gimple_stmt_iterator*) >> ../../gcc/tree-ssa-dse.c:786 >> 0x1179b6e dse_dom_walker::before_dom_children(basic_block_def*) >> ../../gcc/tree-ssa-dse.c:853 >> 0x1a6f659 dom_walker::walk(basic_block_def*) >> ../../gcc/domwalk.c:308 >> 0x1179cb9 execute >> ../../gcc/tree-ssa-dse.c:907 >> >> Where we call: >> Breakpoint 1, bitmap_bit_in_range_p (bmap=0x29d6cd0, start=0, end=515) at >> ../../gcc/sbitmap.c:335 >> 335 bitmap_check_index (bmap, end); >> (gdb) p *bmap >> $1 = {n_bits = 256, size = 4, elms = {255}} >> >> Is it a valid call or should caller check indices? > It doesn't look valid to me. I'll dig into it. > > In general the sbitmap interface requires callers to DTRT -- failure can > easily lead to an out of bounds read or write. It's one of the things I > really dislike about the sbitmap implementation. > > So it's safe to assume that I'm fully supportive of adding more testing > to catch this kind thing. > > Jeff >
Good. Should I prepare fix for the ICE I mentioned or have you been working on that? Thanks, Martin