[llvm-bugs] [Bug 42267] New: segmentation fault of target program caused by loop-reroll with "opt -mem2reg -loop-unswitch -indvars -loop-rotate -loop-unswitch -jump-threading -loop-unroll -jump-threading -loop-reroll"

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=42267

            Bug ID: 42267
           Summary: segmentation fault of target program caused by
                    loop-reroll with "opt -mem2reg -loop-unswitch -indvars
                    -loop-rotate -loop-unswitch -jump-threading
                    -loop-unroll -jump-threading -loop-reroll"
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: Scalar Optimizations
          Assignee: unassignedbugs at nondot.org
          Reporter: cszide at 163.com
                CC: llvm-bugs at lists.llvm.org

Created attachment 22089
  --> https://bugs.llvm.org/attachment.cgi?id=22089&action=edit
.bc file of the source code

$clang -v
clang version 9.0.0 (trunk 362492)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/jack-zhou/Documents/llvm/llvm_truck/llvm2/build/bin
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/8
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.4.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.4.0
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Candidate multilib: x32;@mx32
Selected multilib: .;@m64


$gcc small.c -o small1.out && ./small1.out
0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

$clang small.c -o small2.out && ./small2.out
0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000


$clang -O3 -c -emit-llvm  -mllvm -disable-llvm-optzns small.c

$opt -mem2reg -loop-unswitch -indvars -loop-rotate -loop-unswitch
-jump-threading -loop-unroll -jump-threading  small.bc -o small-opt.bc

$clang small-opt.bc -o small3.out && ./small3.out
Segmentation fault (core dumped)

without loop-reroll pass, the output is correct.
$$opt -mem2reg -loop-unswitch -indvars -loop-rotate -loop-unswitch
-jump-threading -loop-unroll -jump-threading  small.bc -o small-opt1.bc

$clang small-opt1.bc -o small4.out && ./small4.out
0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

---------------------------------------
#include<stdio.h>
int a[8][10][2];
void main() {
  int b, c, d;
  for (b = 0; b < 8; b++)
    for (c = 0; c < 10; c++)
      for (d = 0; d < 2; d++)
        printf("%d", a[b][c][d]);
}

-- 
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/20190613/c114b75f/attachment.html>