https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83926
--- Comment #3 from Will Schmidt <willschm at gcc dot gnu.org> ---
(In reply to Bill Schmidt from comment #2)
> Does this work on GCC 7 (obviously without -mno-fold-gimple)? If so, please
> mark as [8 regression] in title.
looks like No, this also fails on the gcc 7 branch.
(the -mno-fold-gimple option, as well as the vec_div folding, were both added
after gcc7 branched.)
(On a Power7)
# checkout
svn co svn://gcc.gnu.org/svn/gcc/branches/gcc-7-branch gcc-7-branch
# configure
../../gcc-7-branch/configure --enable-languages=c,c++,fortran,objc,obj-c++
--with-cpu=power7 --disable-multilib --with-long-double-128
--prefix=/home/willschm/gcc/install/gcc-7-branch --disable-bootstrap
# check version
~/gcc/build/gcc-7-branch> /home/willschm/gcc/build/gcc-7-branch/gcc/xgcc -v
Using built-in specs.
COLLECT_GCC=/home/willschm/gcc/build/gcc-7-branch/gcc/xgcc
Target: powerpc64-unknown-linux-gnu
Configured with: ../../gcc-7-branch/configure
--enable-languages=c,c++,fortran,objc,obj-c++ --with-cpu=power7
--disable-multilib --with-long-double-128
--prefix=/home/willschm/gcc/install/gcc-7-branch --disable-bootstrap
Thread model: posix
gcc version 7.2.1 20180124 (GCC)
# run
~/gcc/build/gcc-7-branch> /home/willschm/gcc/build/gcc-7-branch/gcc/xgcc
-B/home/willschm/gcc/build/gcc-7-branch/gcc/ /home/willschm/testme.c
-fno-diagnostics-show-caret -fdiagnostics-color=never -maltivec
-ffat-lto-objects -S -o testme.o -m32
/home/willschm/testme.c: In function ‘main’:
/home/willschm/testme.c:19:1: internal compiler error: in
elimination_costs_in_insn, at reload1.c:3617
0x10699b5b elimination_costs_in_insn
../../../gcc-7-branch/gcc/reload1.c:3614
0x1069a3db calculate_elim_costs_all_insns()
../../../gcc-7-branch/gcc/reload1.c:1607
0x10537343 ira_costs()
../../../gcc-7-branch/gcc/ira-costs.c:2261
0x1052f443 ira_build()
../../../gcc-7-branch/gcc/ira-build.c:3420
0x10524187 ira
../../../gcc-7-branch/gcc/ira.c:5308
0x10524187 execute
../../../gcc-7-branch/gcc/ira.c:5619
