wrong code with opt "-mem2reg -loop-rotate -simplifycfg -instcombine -newgvn" on x86_64-linux-gnu #35581
Description
| Bugzilla Link | 36233 |
| Resolution | FIXED |
| Resolved on | Jul 22, 2019 12:17 |
| Version | trunk |
| OS | All |
| CC | @fhahn |
Extended Description
Tested with trunk revision 324202.
$ clangpolly -v
clang version 7.0.0 (http://llvm.org/git/clang.git b9bdf3d4e882e565e4af6a67d419648ef572cd4f) (http://llvm.org/git/llvm.git 2358f76)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/su/bin
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/5
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/5.4.0
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/6
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/6.0.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.4
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.4.7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.6
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.6.4
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.7.4
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.8
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.8.5
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.9
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.9.3
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5.4.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6.0.0
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5.4.0
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Candidate multilib: x32;@MX32
Selected multilib: .;@m64
$
$ clangpolly -O0 small.c; ./a.out
0
$
$ clangpolly -O3 -mllvm -disable-llvm-optzns -c -emit-llvm -o small.bc -w small.c
$ optpolly -mem2reg -loop-rotate -simplifycfg -instcombine -newgvn -o small-opt.bc small.bc
$ clangpolly small-opt.bc
$ ./a.out
1
$
int printf (const char *, ...);
int a = 1, *b = &a, *c = &a;
int main ()
{
int d, e;
for (e = 0; e < 2; e++)
{
d = *b;
*c = d && e;
}
printf ("%d\n", a);
return 0;
}