[llvm-bugs] [Bug 36944] New: wrong code with opt "-sroa -instcombine -loop-deletion -memcpyopt -gvn"

via llvm-bugs llvm-bugs at lists.llvm.org
Wed Mar 28 22:17:25 PDT 2018


https://bugs.llvm.org/show_bug.cgi?id=36944

            Bug ID: 36944
           Summary: wrong code with opt "-sroa -instcombine -loop-deletion
                    -memcpyopt -gvn"
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: Scalar Optimizations
          Assignee: unassignedbugs at nondot.org
          Reporter: su at cs.ucdavis.edu
                CC: llvm-bugs at lists.llvm.org

$ clangpolly -v
clang version 7.0.0 (http://llvm.org/git/clang.git
9a41408814f37f4f864fb3e57aa01919b4d871d8) (llvm/trunk 328613)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/su/bin
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/4.9
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/4.9.4
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/5
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/5.3.0
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/4.7.3
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/4.9.4
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5.3.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6.2.0
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.9
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Candidate multilib: x32;@mx32
Selected multilib: .;@m64
$ 
$ clangpolly -O0 -w small.c; ./a.out
0
$ 
$ clangpolly -O3 -w -mllvm -disable-llvm-optzns -c -emit-llvm -o small.bc
small.c
$ optpolly -sroa -instcombine -loop-deletion -memcpyopt -gvn -o small-opt.bc
small.bc
$ clangpolly small-opt.bc
$ ./a.out
-1911610520
$ 


-------------------------------------


int printf (const char *, ...);

struct S
{
  int b;
  int c; 
  int d; 
} e, *f = &e;

int g;

int j ()
{
  if (g)
    ;
  struct S i = {0, 0, 0};
  while (0)
    ;
  *f = i;
  i.b;
  return 0;
}

int main ()
{  
  j ();
  printf ("%d\n", e.c);
  return 0; 
}

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20180329/047e4dc1/attachment.html>


More information about the llvm-bugs mailing list