[Bug target/99872] [11 Regression] optimizations sometimes lead to missing asm prefixes

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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99872

--- Comment #7 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:b51321bc5193b65b308a26663fc02f786ba6cc89

commit r11-8028-gb51321bc5193b65b308a26663fc02f786ba6cc89
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Wed Apr 7 15:51:15 2021 +0200

    varasm: Fix up constpool alias handling [PR99872]

    Last year, I have added in
r11-2944-g0106300f6c3f7bae5eb1c46dbd45aa07c94e1b15
    (aka PR54201 fix) code to find bitwise duplicates in constant pool and
output
    them as aliases instead of duplicating the data.

    Unfortunately this broke mingw32 -m32.
    On most targets, ASM_GENERATE_INTERNAL_LABEL with "LC" emits something like
    *.LC123 and the targets don't add user label prefixes, so the aliases
    that we print should be something like
            .set    .LC5, .LC6
    or
            .set    .LC5, .LC6 + 8
    and I wasn't sure if ASM_OUTPUT_DEF can handle the * and therefore I have
    stripped it.
    But, on mingw32 -m32, ASM_GENERATE_INTERNAL_LABEL with "LC" emits
    *LC123 and the target has user label prefixes, which means what I wrote
    results in
    LC6:
            ...
            .set    _LC5, _LC6
    which results in unresolved symbols.  I went through the ASM_OUTPUT_DEF
    definitions of all targets and all of them use assemble_name twice under
    the hood (with various differences on what they print before, in between or
    after those names).  And assemble_name handles the name encoding properly,
    so if we pass it ASM_OUTPUT_DEF (..., "*.LC123", "*.LC456+16") it will
    emit .LC123 and .LC456+16 and if we pass it "*LC789", it will emit
    LC789.

    2021-04-07  Jakub Jelinek  <jakub@redhat.com>

            PR target/99872
            * varasm.c (output_constant_pool_contents): Don't strip name
encoding
            from XSTR (desc->sym, 0) or from label before passing those to
            ASM_OUTPUT_DEF.