Re: Restricted or no run time in Ada

[Vadim Godunko <vgodunko@gmail.com>]

On Jan 4, 3:46 pm, Georg Bauhaus <rm.tsoh+bauh...@maps.futureapps.de>
wrote:
>
> Have you instructed GNAT to not perform any kind of
> optimization?
>
> Is this an option using Gela? (For example, to verify
> close correspondence of source and object code.)

I have following assembler code, produced by GNAT GPL 2007 and GCC
GNAT 4.3.0 with size optimization and Ada semantic (don't forget
enable overflow checking!):

$ gcc -c -gnato -O2 test.adb
$ objdump --disassemble test.o

test.o:     file format elf32-i386

Disassembly of section .text:

00000000 <_ada_test>:
   0:   55                      push   %ebp
   1:   89 e5                   mov    %esp,%ebp
   3:   53                      push   %ebx
   4:   83 ec 14                sub    $0x14,%esp
   7:   8b 45 08                mov    0x8(%ebp),%eax
   a:   89 c2                   mov    %eax,%edx
   c:   89 c1                   mov    %eax,%ecx
   e:   c1 fa 1f                sar    $0x1f,%edx
  11:   83 c1 01                add    $0x1,%ecx
  14:   89 d3                   mov    %edx,%ebx
  16:   89 c8                   mov    %ecx,%eax
  18:   83 d3 00                adc    $0x0,%ebx
  1b:   05 00 00 00 80          add    $0x80000000,%eax
  20:   89 da                   mov    %ebx,%edx
  22:   83 d2 00                adc    $0x0,%edx
  25:   83 fa 00                cmp    $0x0,%edx
  28:   76 16                   jbe    40 <_ada_test+0x40>
  2a:   c7 44 24 04 03 00 00    movl   $0x3,0x4(%esp)
  31:   00
  32:   c7 04 24 00 00 00 00    movl   $0x0,(%esp)
  39:   e8 fc ff ff ff          call   3a <_ada_test+0x3a>
  3e:   66 90                   xchg   %ax,%ax
  40:   89 c8                   mov    %ecx,%eax
  42:   83 c4 14                add    $0x14,%esp
  45:   5b                      pop    %ebx
  46:   5d                      pop    %ebp
  47:   c3                      ret