Re: [PATCH] Fix another reg-stack recovery bug (PR target/84828)

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Tue, Mar 13, 2018 at 12:55 AM, Uros Bizjak <ubizjak@gmail.com> wrote:
> On Mon, Mar 12, 2018 at 10:10 PM, Jakub Jelinek <jakub@redhat.com> wrote:
>> Hi!
>>
>> As Martin reported, the same testcase added recently ICEs differently
>> with different options on x86_64-linux, the problem is that we
>> sometimes emit insns before a CODE_LABEL of the next bb rather than after
>> the last insn in the previous bb, and expect we can just fix up BB_END
>> of the previous bb; fortunately that doesn't change BB_HEAD of the next
>> bb, but still we need to at least update INSN_BLOCK and make sure df knows
>> that too.
>>
>> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
>> trunk?
>>
>> The testcase still ICEs on i686-linux (preexisting bug, ICEs the same
>> without this patch or even before the previous patch), will handle that
>> tomorrow.
>>
>> 2018-03-12  Jakub Jelinek  <jakub@redhat.com>
>>
>>         PR target/84828
>>         * reg-stack.c (change_stack): Change update_end var from int to
>>         rtx_insn *, if non-NULL don't update just BB_END (current_block), but
>>         also call set_block_for_insn on the newly added insns and rescan.
>>
>>         * g++.dg/ext/pr84828.C: New test.
>
> LGTM.
>
> Uros.
>

I got:

spawn -ignore SIGHUP
/export/gnu/import/git/gcc-test/bld/gcc/testsuite/g++/../../xg++
-B/export/gnu/import/git/gcc-test/bld/gcc/testsuite/g++/../../
/export/gnu/import/git/gcc-test/src-trunk/gcc/testsuite/g++.dg/ext/pr84828.C
-fno-diagnostics-show-caret -fdiagnostics-color=never -nostdinc++
-I/export/gnu/import/git/gcc-test/bld/x86_64-pc-linux-gnu/libstdc++-v3/include/x86_64-pc-linux-gnu
-I/export/gnu/import/git/gcc-test/bld/x86_64-pc-linux-gnu/libstdc++-v3/include
-I/export/gnu/import/git/gcc-test/src-trunk/libstdc++-v3/libsupc++
-I/export/gnu/import/git/gcc-test/src-trunk/libstdc++-v3/include/backward
-I/export/gnu/import/git/gcc-test/src-trunk/libstdc++-v3/testsuite/util
-fmessage-length=0 -std=gnu++98 -Og -mno-sse2 -S -o pr84828.s^M
/export/gnu/import/git/gcc-test/src-trunk/gcc/testsuite/g++.dg/ext/pr84828.C:
In function 'void foo(float, double)':^M
/export/gnu/import/git/gcc-test/src-trunk/gcc/testsuite/g++.dg/ext/pr84828.C:10:35:
error: output constraint 0 must specify a single register^M
during RTL pass: stack^M
/export/gnu/import/git/gcc-test/src-trunk/gcc/testsuite/g++.dg/ext/pr84828.C:13:1:
internal compiler error: in move_for_stack_reg, at reg-stack.c:1108^M
0xeaf075 move_for_stack_reg^M
        ../../src-trunk/gcc/reg-stack.c:1108^M
0xeb26ea subst_stack_regs^M
        ../../src-trunk/gcc/reg-stack.c:2438^M
0xeb2950 convert_regs_1^M
        ../../src-trunk/gcc/reg-stack.c:3072^M
0xeb2950 convert_regs_2^M
        ../../src-trunk/gcc/reg-stack.c:3207^M
0xeb4798 convert_regs^M
        ../../src-trunk/gcc/reg-stack.c:3242^M
0xeb4798 reg_to_stack^M
        ../../src-trunk/gcc/reg-stack.c:3367^M
0xeb4798 rest_of_handle_stack_regs^M
        ../../src-trunk/gcc/reg-stack.c:3422^M
0xeb4798 execute^M
        ../../src-trunk/gcc/reg-stack.c:3453^M
Please submit a full bug report,^M
with preprocessed source if appropriate.^M
Please include the complete backtrace with any bug report.^M
See <https://gcc.gnu.org/bugs/> for instructions.^M
compiler exited with status 1
FAIL: g++.dg/ext/pr84828.C  -std=gnu++98 (internal compiler error)
PASS: g++.dg/ext/pr84828.C  -std=gnu++98  (test for errors, line 10)
FAIL: g++.dg/ext/pr84828.C  -std=gnu++98 (test for excess errors)

-- 
H.J.