[Bug tree-optimization/67213] When compiling for size with -Os loops can get bigger after peeling

[fredrik.hederstierna@securitas-direct.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67213

--- Comment #6 from Fredrik Hederstierna <fredrik.hederstierna@securitas-direct.com> ---
Same thing for x86, not only ARM:


bash# gcc --version
gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609


bash# gcc -c test.c -Os --param max-completely-peel-times=5
bash# objdump -dath test.o


Disassembly of section .text:

000000000000000f <test_iter_6>:
   f:   c6 05 00 00 00 00 00    movb   $0x0,0x0(%rip)        # 16
<test_iter_6+0x7>
  16:   c6 05 00 00 00 00 01    movb   $0x1,0x0(%rip)        # 1d
<test_iter_6+0xe>
  1d:   c6 05 00 00 00 00 02    movb   $0x2,0x0(%rip)        # 24
<test_iter_6+0x15>
  24:   c6 05 00 00 00 00 03    movb   $0x3,0x0(%rip)        # 2b
<test_iter_6+0x1c>
  2b:   c6 05 00 00 00 00 04    movb   $0x4,0x0(%rip)        # 32
<test_iter_6+0x23>
  32:   c6 05 00 00 00 00 05    movb   $0x5,0x0(%rip)        # 39
<test_iter_6+0x2a>
  39:   c3                      retq   


bash# gcc -c test.c -Os --param max-completely-peel-times=4
bash# objdump -dath test.o


Disassembly of section .text:

000000000000000f <test_iter_6>:
   f:   31 c0                   xor    %eax,%eax
  11:   88 80 00 00 00 00       mov    %al,0x0(%rax)
  17:   48 ff c0                inc    %rax
  1a:   48 83 f8 06             cmp    $0x6,%rax
  1e:   75 f1                   jne    11 <test_iter_6+0x2>
  20:   c3                      retq