[Bug target/113995] ICE: in change_address_1, at emit-rtl.cc:2299 with [[arm::streaming_compatible]] and -march=armv9-a+sve -finstrument-functions -fstack-clash-protection

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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113995

--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Richard Sandiford <rsandifo@gcc.gnu.org>:

https://gcc.gnu.org/g:ad4df8cd080c9be738f61b5e91cc70a594c4419d

commit r14-9098-gad4df8cd080c9be738f61b5e91cc70a594c4419d
Author: Richard Sandiford <richard.sandiford@arm.com>
Date:   Wed Feb 21 11:12:27 2024 +0000

    aarch64: Stack-clash prologues and VG saves [PR113995]

    This patch fixes an ICE for a combination of:

    - -fstack-clash-protection
    - a frame that has SVE save slots
    - a frame that has no GPR save slots
    - a frame that has a VG save slot

    The allocation code was folding the SVE save slot allocation into
    the initial frame allocation, so that we had one allocation of
    size <size of SVE registers> + 16.  But the VG save code itself
    expected the allocations to remain separate, since it wants to
    store at a constant offset from SP or FP.

    The VG save isn't shrink-wrapped and so acts as a probe of the
    initial allocations.  It should therefore be safe to keep separate
    allocations in this case.

    The scans in locally_streaming_1.c expect no stack clash protection,
    so the patch forces that and adds a separate compile-only test for
    when protection is enabled.

    gcc/
            PR target/113995
            * config/aarch64/aarch64.cc (aarch64_expand_prologue): Don't
            fold the SVE allocation into the initial allocation if the
            initial allocation includes a VG save.

    gcc/testsuite/
            PR target/113995
            * gcc.target/aarch64/sme/locally_streaming_1.c: Require
            -fno-stack-clash-protection.
            * gcc.target/aarch64/sme/locally_streaming_1_scp.c: New test.