[Bug target/86838] [9 Regression] ICE in gen_aarch64_frecpe, at ./insn-opinit.h:571

["rsandifo at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86838

--- Comment #3 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> ---
Author: rsandifo
Date: Tue Aug  7 17:22:19 2018
New Revision: 263362

URL: https://gcc.gnu.org/viewcvs?rev=263362&root=gcc&view=rev
Log:
[AArch64] Fix -mlow-precision-div (PR 86838)

The "@" handling broke -mlow-precision-div, because the scalar forms of
the instruction were provided by a pattern that also provided FRECPX
(and so were parameterised on an unspec code as well as a mode),
while the SIMD versions had a dedicated FRECPE pattern.  This patch
moves the scalar FRECPE handling to the SIMD pattern too (as for FRECPS)
and uses a separate pattern for FRECPX.

The convention in aarch64-simd-builtins.def seemed to be to add
comments only if the mapping wasn't obvious (i.e. not just sticking
"aarch64_" on the beginning and "<mode>" on the end), so the patch
deletes the reference to the combined pattern instead of rewording it.

There didn't seem to be any coverage of -mlow-precision-div in the
testsuite, so the patch adds some tests for it.

2018-08-07  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
        PR target/86838
        * config/aarch64/iterators.md (FRECP, frecp_suffix): Delete.
        * config/aarch64/aarch64-simd.md
        (aarch64_frecp<FRECP:frecp_suffix><mode>): Fold FRECPE into...
        (@aarch64_frecpe<mode>): ...here and the move FRECPX to...
        (aarch64_frecpx<mode>): ...this new pattern.
        * config/aarch64/aarch64-simd-builtins.def: Remove comment
        about aarch64_frecp<FRECP:frecp_suffix><mode>.

gcc/testsuite/
        PR target/86838
        * gcc.target/aarch64/frecpe_1.c: New test.
        * gcc.target/aarch64/frecpe_2.c: Likewise.

Added:
    trunk/gcc/testsuite/gcc.target/aarch64/frecpe_1.c
    trunk/gcc/testsuite/gcc.target/aarch64/frecpe_2.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/aarch64/aarch64-simd-builtins.def
    trunk/gcc/config/aarch64/aarch64-simd.md
    trunk/gcc/config/aarch64/iterators.md
    trunk/gcc/testsuite/ChangeLog