[Bug c/95142] ICE when compiling certain logic with -Ofast and -mpretend-cmove when dealing with floats

["gabravier at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95142

Gabriel Ravier <gabravier at gmail dot com> changed:

           What    |Removed                     |Added
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                 CC|                            |gabravier at gmail dot com

--- Comment #1 from Gabriel Ravier <gabravier at gmail dot com> ---
I can reproduce this on Fedora 32 with `sh-linux-gnu-gcc` (which uses GCC 9.2)
: 

$ sh-linux-gnu-gcc -Ofast -m4 -mpretend-cmove -c ice_sh4.c 
ice_sh4.c: In function ‘call_create’:
ice_sh4.c:48:1: error: unrecognizable insn:
   48 | }
      | ^
(insn 26 25 27 2 (parallel [
            (set (reg:SI 147 t)
                (ge:SI (reg/v:SF 170 [ size_1 ])
                    (reg/v:SF 167 [ size_0 ])))
            (clobber (reg:SI 155 fpscr1))
            (use (reg:SI 154 fpscr0))
        ]) "ice_sh4.c":41:29 -1
     (nil))
during RTL pass: vregs
ice_sh4.c:48:1: internal compiler error: in extract_insn, at recog.c:2310
0x7f37befd0041 __libc_start_main
        ../csu/libc-start.c:308
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://bugzilla.redhat.com/bugzilla/> for instructions.
The bug is not reproducible, so it is likely a hardware or OS problem.
$ sh-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=/usr/bin/sh-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/sh-linux-gnu/9/lto-wrapper
Target: sh-linux-gnu
Configured with: ../gcc-9.2.1-20190827/configure --bindir=/usr/bin
--build=x86_64-redhat-linux-gnu --datadir=/usr/share --disable-decimal-float
--disable-dependency-tracking --disable-gold --disable-libgcj --disable-libgomp
--disable-libmpx --disable-libquadmath --disable-libssp
--disable-libunwind-exceptions --disable-shared --disable-silent-rules
--disable-sjlj-exceptions --disable-threads --with-ld=/usr/bin/sh-linux-gnu-ld
--enable-__cxa_atexit --enable-checking=release --enable-gnu-unique-object
--enable-initfini-array --enable-languages=c,c++ --enable-linker-build-id
--enable-lto --enable-nls --enable-obsolete --enable-plugin
--enable-targets=all --exec-prefix=/usr --host=x86_64-redhat-linux-gnu
--includedir=/usr/include --infodir=/usr/share/info --libexecdir=/usr/libexec
--localstatedir=/var --mandir=/usr/share/man --prefix=/usr
--program-prefix=sh-linux-gnu- --sbindir=/usr/sbin --sharedstatedir=/var/lib
--sysconfdir=/etc --target=sh-linux-gnu
--with-bugurl=http://bugzilla.redhat.com/bugzilla/
--with-gcc-major-version-only --with-isl --with-newlib
--with-plugin-ld=/usr/bin/sh-linux-gnu-ld
--with-sysroot=/usr/sh-linux-gnu/sys-root --with-system-libunwind
--with-system-zlib --without-headers
--with-multilib-list=m1,m2,m2e,m2a,m2a-single,m4,m4-single,m4-single-only,m4-nofpu
--with-linker-hash-style=gnu
Thread model: single
gcc version 9.2.1 20190827 (Red Hat Cross 9.2.1-3) (GCC) 


Reproducing it requires `-m4` here (doesn't work with nothing or another
architecture like `-m3`), so it is most likely a bug specific to SH4-specific
code.