i386: -fno-force-addr working?

[Etienne LORRAIN]

  Hello,

 For every "recent" egcs/gcc, I have this:

------------------------------------------
bash-2.02$ cat optim.c
struct {
  void (*fct1) (void);
  void (*fct2) (void);
  void (*fct3) (void);
  void (*fct4) (void);
  void (*fct5) (void);
  void (*fct6) (void);
  void (*fct7) (void);
  } thestruct;

void fct (void)
  {
  thestruct.fct1();
  thestruct.fct2();
  thestruct.fct3();
  thestruct.fct4();
  thestruct.fct5();
  thestruct.fct6();
  thestruct.fct7();
  }
bash-2.02$ xgcc -O2 -S -fomit-frame-pointer -fno-force-addr optim.c
bash-2.02$ cat optim.s
        .file   "optim.c"
        .version        "01.01"
gcc2_compiled.:
___gnu_compiled_c:
.text
        .align 16
.globl _fct
        .def    _fct;   .scl    2;      .type   32;     .endef
_fct:
        movl    _thestruct, %eax
        subl    $12, %esp
        call    *%eax
        movl    _thestruct+4, %eax
        call    *%eax
        movl    _thestruct+8, %eax
        call    *%eax
        movl    _thestruct+12, %eax
        call    *%eax
        movl    _thestruct+16, %eax
        call    *%eax
        movl    _thestruct+20, %eax
        call    *%eax
        movl    _thestruct+24, %eax
        call    *%eax
        addl    $12, %esp
        ret
        .comm   _thestruct, 32   # 28
bash-2.02$ xgcc -v
Using builtin specs.
gcc version 2.96 19991201 (experimental)
bash-2.02$
------------------------------------------

  I do not understand why the opcodes:
        call (_thestruct+24)
  are not generated, or even better:
        movl _thestruct, %ebx
        call 4(%ebx)
        call 8(%ebx)
  but the later is an optimisation thing,
  the former seems to show that -fno-force-addr
  is not working - or that there is a problem in
  the "call" description. I am mode interrested
  by the code size than the code speed - but it
  seems to be the same (or better) speed anyway,
  and will take less space in the cache.

  Have a nice day,
  Etienne.
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