https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87218
Bug ID: 87218
Summary: Extremely long compile time with 710 line Fortran code
using -O2
Product: gcc
Version: 8.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: toon at moene dot org
Target Milestone: ---
Created attachment 44660
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44660&action=edit
Source of Fortran routine taking 12+ minutes to compile
Attached file compiled with:
toon@moene:~/src$ gfortran -v -ftime-report -O2 -S suafn.f90
Using built-in specs.
COLLECT_GCC=gfortran
OFFLOAD_TARGET_NAMES=nvptx-none
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 8.2.0-4'
--with-bugurl=file:///usr/share/doc/gcc-8/README.Bugs
--enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++ --prefix=/usr
--with-gcc-major-version-only --program-suffix=-8
--program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes
--with-default-libstdcxx-abi=new --enable-gnu-unique-object
--disable-vtable-verify --enable-libmpx --enable-plugin --enable-default-pie
--with-system-zlib --with-target-system-zlib --enable-objc-gc=auto
--enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64
--with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic
--enable-offload-targets=nvptx-none --without-cuda-driver
--enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu
--target=x86_64-linux-gnu
Thread model: posix
gcc version 8.2.0 (Debian 8.2.0-4)
COLLECT_GCC_OPTIONS='-v' '-ftime-report' '-O2' '-S' '-mtune=generic'
'-march=x86-64'
/usr/lib/gcc/x86_64-linux-gnu/8/f951 suafn.f90 -quiet -dumpbase suafn.f90
-mtune=generic -march=x86-64 -auxbase suafn -O2 -version -ftime-report -o
suafn.s -fintrinsic-modules-path /usr/lib/gcc/x86_64-linux-gnu/8/finclude
GNU Fortran (Debian 8.2.0-4) version 8.2.0 (x86_64-linux-gnu)
compiled by GNU C version 8.2.0, GMP version 6.1.2, MPFR version 4.0.1,
MPC version 1.1.0, isl version isl-0.20-GMP
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
GNU Fortran2008 (Debian 8.2.0-4) version 8.2.0 (x86_64-linux-gnu)
compiled by GNU C version 8.2.0, GMP version 6.1.2, MPFR version 4.0.1,
MPC version 1.1.0, isl version isl-0.20-GMP
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
gives this time report:
Time variable usr sys wall
GGC
phase setup : 0.00 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
182 kB ( 0%)
phase parsing : 0.05 ( 0%) 0.00 ( 0%) 0.08 ( 0%)
7841 kB ( 6%)
phase opt and generate : 534.57 (100%) 0.45 (100%) 553.90 (100%)
127110 kB ( 94%)
dump files : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
0 kB ( 0%)
callgraph construction : 0.03 ( 0%) 0.00 ( 0%) 0.06 ( 0%)
4906 kB ( 4%)
ipa function summary : 0.13 ( 0%) 0.00 ( 0%) 0.09 ( 0%)
5 kB ( 0%)
ipa pure const : 0.00 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
ipa icf : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
ipa free inline summary : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
0 kB ( 0%)
cfg cleanup : 487.98 ( 91%) 0.04 ( 9%) 503.57 ( 91%)
1045 kB ( 1%)
trivially dead code : 0.10 ( 0%) 0.00 ( 0%) 0.10 ( 0%)
0 kB ( 0%)
df scan insns : 0.08 ( 0%) 0.03 ( 7%) 0.10 ( 0%)
0 kB ( 0%)
df multiple defs : 0.10 ( 0%) 0.00 ( 0%) 0.10 ( 0%)
0 kB ( 0%)
df reaching defs : 0.29 ( 0%) 0.01 ( 2%) 0.31 ( 0%)
0 kB ( 0%)
df live regs : 1.07 ( 0%) 0.00 ( 0%) 1.14 ( 0%)
0 kB ( 0%)
df live&initialized regs : 0.26 ( 0%) 0.00 ( 0%) 0.29 ( 0%)
0 kB ( 0%)
df must-initialized regs : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
0 kB ( 0%)
df use-def / def-use chains : 0.12 ( 0%) 0.00 ( 0%) 0.12 ( 0%)
0 kB ( 0%)
df live reg subwords : 0.02 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
df reg dead/unused notes : 0.79 ( 0%) 0.01 ( 2%) 0.87 ( 0%)
4881 kB ( 4%)
register information : 0.19 ( 0%) 0.00 ( 0%) 0.19 ( 0%)
0 kB ( 0%)
alias analysis : 0.26 ( 0%) 0.00 ( 0%) 0.26 ( 0%)
8707 kB ( 6%)
alias stmt walking : 24.54 ( 5%) 0.16 ( 36%) 27.03 ( 5%)
429 kB ( 0%)
register scan : 0.05 ( 0%) 0.00 ( 0%) 0.05 ( 0%)
0 kB ( 0%)
rebuild jump labels : 0.06 ( 0%) 0.00 ( 0%) 0.05 ( 0%)
0 kB ( 0%)
parser (global) : 0.05 ( 0%) 0.00 ( 0%) 0.08 ( 0%)
7773 kB ( 6%)
inline parameters : 0.19 ( 0%) 0.00 ( 0%) 0.11 ( 0%)
516 kB ( 0%)
tree gimplify : 0.48 ( 0%) 0.01 ( 2%) 0.59 ( 0%)
6059 kB ( 4%)
tree eh : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
0 kB ( 0%)
tree VRP : 0.04 ( 0%) 0.00 ( 0%) 0.05 ( 0%)
6 kB ( 0%)
tree Early VRP : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
3 kB ( 0%)
tree copy propagation : 0.00 ( 0%) 0.01 ( 2%) 0.00 ( 0%)
0 kB ( 0%)
tree PTA : 0.45 ( 0%) 0.01 ( 2%) 0.46 ( 0%)
1290 kB ( 1%)
tree SSA rewrite : 0.01 ( 0%) 0.01 ( 2%) 0.00 ( 0%)
2444 kB ( 2%)
tree operand scan : 0.02 ( 0%) 0.01 ( 2%) 0.05 ( 0%)
1095 kB ( 1%)
dominator optimization : 0.03 ( 0%) 0.01 ( 2%) 0.04 ( 0%)
5347 kB ( 4%)
tree SRA : 0.03 ( 0%) 0.00 ( 0%) 0.03 ( 0%)
0 kB ( 0%)
tree CCP : 0.02 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
tree reassociation : 0.01 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
tree PRE : 0.12 ( 0%) 0.00 ( 0%) 0.12 ( 0%)
3964 kB ( 3%)
tree FRE : 0.16 ( 0%) 0.00 ( 0%) 0.17 ( 0%)
2792 kB ( 2%)
tree code sinking : 0.01 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
tree forward propagate : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
tree conservative DCE : 0.03 ( 0%) 0.01 ( 2%) 0.07 ( 0%)
0 kB ( 0%)
tree aggressive DCE : 0.02 ( 0%) 0.02 ( 4%) 0.04 ( 0%)
6 kB ( 0%)
tree DSE : 0.10 ( 0%) 0.00 ( 0%) 0.10 ( 0%)
2838 kB ( 2%)
tree strlen optimization : 8.29 ( 2%) 0.00 ( 0%) 8.66 ( 2%)
312 kB ( 0%)
expand : 0.14 ( 0%) 0.02 ( 4%) 0.17 ( 0%)
24881 kB ( 18%)
post expand cleanups : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
lower subreg : 0.02 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
forward prop : 0.35 ( 0%) 0.01 ( 2%) 0.51 ( 0%)
3274 kB ( 2%)
CSE : 0.54 ( 0%) 0.00 ( 0%) 0.54 ( 0%)
1759 kB ( 1%)
dead code elimination : 0.14 ( 0%) 0.00 ( 0%) 0.13 ( 0%)
0 kB ( 0%)
dead store elim1 : 0.24 ( 0%) 0.00 ( 0%) 0.23 ( 0%)
1141 kB ( 1%)
dead store elim2 : 0.19 ( 0%) 0.01 ( 2%) 0.19 ( 0%)
1551 kB ( 1%)
CPROP : 0.64 ( 0%) 0.00 ( 0%) 0.64 ( 0%)
2882 kB ( 2%)
PRE : 0.02 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
CSE 2 : 0.27 ( 0%) 0.00 ( 0%) 0.28 ( 0%)
736 kB ( 1%)
combiner : 1.20 ( 0%) 0.00 ( 0%) 1.27 ( 0%)
5700 kB ( 4%)
if-conversion : 0.00 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
integrated RA : 1.42 ( 0%) 0.01 ( 2%) 1.51 ( 0%)
13454 kB ( 10%)
LRA non-specific : 0.33 ( 0%) 0.00 ( 0%) 0.35 ( 0%)
2055 kB ( 2%)
LRA virtuals elimination : 0.08 ( 0%) 0.00 ( 0%) 0.07 ( 0%)
264 kB ( 0%)
LRA reload inheritance : 0.06 ( 0%) 0.00 ( 0%) 0.05 ( 0%)
309 kB ( 0%)
LRA create live ranges : 0.21 ( 0%) 0.00 ( 0%) 0.21 ( 0%)
369 kB ( 0%)
LRA hard reg assignment : 0.02 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
LRA rematerialization : 0.06 ( 0%) 0.00 ( 0%) 0.06 ( 0%)
0 kB ( 0%)
reload CSE regs : 0.30 ( 0%) 0.00 ( 0%) 0.30 ( 0%)
2289 kB ( 2%)
ree : 0.02 ( 0%) 0.00 ( 0%) 0.03 ( 0%)
0 kB ( 0%)
thread pro- & epilogue : 0.04 ( 0%) 0.00 ( 0%) 0.04 ( 0%)
7 kB ( 0%)
if-conversion 2 : 0.05 ( 0%) 0.00 ( 0%) 0.05 ( 0%)
0 kB ( 0%)
peephole 2 : 0.06 ( 0%) 0.00 ( 0%) 0.06 ( 0%)
1687 kB ( 1%)
hard reg cprop : 0.06 ( 0%) 0.00 ( 0%) 0.06 ( 0%)
150 kB ( 0%)
scheduling 2 : 1.30 ( 0%) 0.06 ( 13%) 1.51 ( 0%)
9237 kB ( 7%)
machine dep reorg : 0.08 ( 0%) 0.00 ( 0%) 0.08 ( 0%)
0 kB ( 0%)
reorder blocks : 0.07 ( 0%) 0.00 ( 0%) 0.07 ( 0%)
0 kB ( 0%)
shorten branches : 0.09 ( 0%) 0.00 ( 0%) 0.09 ( 0%)
0 kB ( 0%)
final : 0.13 ( 0%) 0.00 ( 0%) 0.14 ( 0%)
2362 kB ( 2%)
variable output : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
9 kB ( 0%)
straight-line strength reduction : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
0 kB ( 0%)
store merging : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
698 kB ( 1%)
rest of compilation : 0.22 ( 0%) 0.00 ( 0%) 0.22 ( 0%)
4823 kB ( 4%)
remove unused locals : 0.02 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
address taken : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
TOTAL : 534.62 0.45 553.99
135134 kB
COMPILER_PATH=/usr/lib/gcc/x86_64-linux-gnu/8/:/usr/lib/gcc/x86_64-linux-gnu/8/:/usr/lib/gcc/x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/8/:/usr/lib/gcc/x86_64-linux-gnu/
LIBRARY_PATH=/usr/lib/gcc/x86_64-linux-gnu/8/:/usr/lib/gcc/x86_64-linux-gnu/8/../../../x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/8/../../../../lib/:/lib/x86_64-linux-gnu/:/lib/../lib/:/usr/lib/x86_64-linux-gnu/:/usr/lib/../lib/:/usr/lib/gcc/x86_64-linux-gnu/8/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-v' '-ftime-report' '-O2' '-S' '-mtune=generic'
'-march=x86-64'
