[Bug tree-optimization/13563] if-conversion not agressive enough

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=13563

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |msebor at gcc dot gnu.org
      Known to fail|                            |3.3, 4.5.3, 4.8.3, 4.9.3,
                   |                            |5.3.0, 6.3.0, 7.0

--- Comment #3 from Martin Sebor <msebor at gcc dot gnu.org> ---
No progress in GCC 7.0:

$ cat t.c && gcc -O2 -S -Wall -Wextra -Wpedantic -Wshadow
-fdump-tree-optimized=/dev/stdout -o/dev/stdout  t.c

void foo (int);

void bar (int a)
{
  if (a)
    foo (1);
  else
    foo (0);
}

void baz (int a)
{
  foo (!!a);
}
        .file   "t.c"

;; Function bar (bar, funcdef_no=0, decl_uid=1797, cgraph_uid=0,
symbol_order=0)

bar (int a)
{
  <bb 2> [100.00%]:
  if (a_2(D) != 0)
    goto <bb 3>; [46.00%]
  else
    goto <bb 4>; [54.00%]

  <bb 3> [46.00%]:
  foo (1); [tail call]
  goto <bb 5>; [100.00%]

  <bb 4> [54.00%]:
  foo (0); [tail call]

  <bb 5> [100.00%]:
  return;

}


        .text
        .p2align 4,,15
        .globl  bar
        .type   bar, @function
bar:
.LFB0:
        .cfi_startproc
        testl   %edi, %edi
        jne     .L4
        xorl    %edi, %edi
        jmp     foo
        .p2align 4,,10
        .p2align 3
.L4:
        movl    $1, %edi
        jmp     foo
        .cfi_endproc
.LFE0:
        .size   bar, .-bar

;; Function baz (baz, funcdef_no=1, decl_uid=1800, cgraph_uid=1,
symbol_order=1)

baz (int a)
{
  _Bool _1;
  int _2;

  <bb 2> [100.00%]:
  _1 = a_3(D) != 0;
  _2 = (int) _1;
  foo (_2); [tail call]
  return;

}


        .p2align 4,,15
        .globl  baz
        .type   baz, @function
baz:
.LFB1:
        .cfi_startproc
        testl   %edi, %edi
        setne   %dil
        movzbl  %dil, %edi
        jmp     foo
        .cfi_endproc
.LFE1:
        .size   baz, .-baz
        .ident  "GCC: (GNU) 7.0.0 20170110 (experimental)"
        .section        .note.GNU-stack,"",@progbits