[Bug tree-optimization/32306] New: Bad Code generation ( Tree optimization )

["pranav dot bhandarkar at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

For the following Code Snippet
void bar ()
{

  b1 = foo(1);
  b2 = foo(1);
  b3 = foo(1);
  b4 = foo(1);
  b5 = foo(1);
  b6 = foo(1);
  b7 = foo(1);
  b8 = foo(1);
  b9 = foo(1);
  b10 = foo(1);
  b11 = foo(1);
  b12 = foo(1);

  array[0] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;
  array[1] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;
  array[2] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;
  array[3] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;
  array[4] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;
  array[5] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;
  array[6] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;
  array[7] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;
  array[8] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;
  array[9] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;
  array[10] = b1 && b2 && b3 && b4 && b5 && b6 && b7 && b8 && b9 && b10 && b11
&& b12;

  return;
}

Where b ( from b1 to b12) are all declared static short b1, static short b2
etc.
and array is static short array[11].
This should generate code such as

if (b1 == 0) goto L1 else goto L2
L2:
if (b2 == 0) goto L1 else goto L3
L3:
if (b3 == 0) goto L1 else goto L4
L4:
if (b4 == 0) goto L1 else goto L5
L5:
if (b5 == 0) goto L1 else goto L6
L6:
if (b6 == 0) goto L1 else goto L7
L7:
if (b7 == 0) goto L1 else goto L8
L8:
if (b8 == 0) goto L1 else goto L9
L9:
if (b9 == 0) goto L1 else goto L10
L10:
if (b10 == 0) goto L1 else goto L11
L11:
if (b11 == 0) goto L1 else goto L12
L12:
if (b12 == 0) goto L1 else goto L13
L13:
array[i]=1 (for i from 0 to 10)
return

L1:
array[i]=0 (for i from 0 to 10)
return

This is exactly what 4.1 generates but 4.3 fails to combine the if sequences.
Version Details:
GNU C version 4.3.0 20070316 (experimental) (arm-none-eabi)
        compiled by GNU C version 3.4.6 (Ubuntu 3.4.6-1ubuntu2).
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096


-- 
           Summary: Bad Code generation ( Tree optimization )
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pranav dot bhandarkar at gmail dot com
GCC target triplet: arm-none-eabi


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32306