[Bug c/45416] New: Code size regression between 4.6(4.5) and 4.4

["bmei at broadcom dot com" <gcc-bugzilla at gcc dot gnu dot org>]

This is a performance/size regression between 4.6 (4.5) and 4.4. 

The C code:
int foo(long long a)
{
   if (a & (long long) 0x400)
      return 1;
   return 0;
}

Assemble code generated by 4.6 trunk:
foo:
.LFB0:
        .cfi_startproc
        pushq   %rbp
        .cfi_def_cfa_offset 16
        movq    %rsp, %rbp
        .cfi_offset 6, -16
        .cfi_def_cfa_register 6
        movq    %rdi, -8(%rbp)
        movq    -8(%rbp), %rax
        andl    $1024, %eax
        testq   %rax, %rax
        je      .L2
        movl    $1, %eax
        jmp     .L3
.L2:
        movl    $0, %eax
.L3:
        popq    %rbp
        .cfi_def_cfa 7, 8
        ret
        .cfi_endproc

Assemble code generated  by 4.4.0:
foo:
.LFB0:
        .cfi_startproc
        shrq    $10, %rdi
        movl    %edi, %eax
        andl    $1, %eax
        ret
        .cfi_endproc

After tree optimizations, both compilers produce different
but essentially same forms. RTL expander and later passes 
then go on to do different optimizations and generate very
different code.


-- 
           Summary: Code size regression between 4.6(4.5) and 4.4
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bmei at broadcom dot com
  GCC host triplet: x86_64-unknown-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45416