GCC 4.4: Avoid range check on switch/case statement in gcc?

Question

This is only an issue on GCC versions prior to 4.4, this was fixed in GCC 4.5.

Is it possible to tell the compiler the variable used in a switch fits within the provided

Answer 1

I tried compiling something simple and comparable with -O5 and -fno-inline (my f0-f7 functions were trivial) and it generated this:

 8048420:   55                      push   %ebp ;; function preamble
 8048421:   89 e5                   mov    %esp,%ebp ;; Yeah, yeah, it's a function.
 8048423:   83 ec 04                sub    $0x4,%esp ;; do stuff with the stack
 8048426:   8b 45 08                mov    0x8(%ebp),%eax ;; x86 sucks, we get it
 8048429:   83 e0 07                and    $0x7,%eax ;; Do the (a & 0x7)
 804842c:   ff 24 85 a0 85 04 08    jmp    *0x80485a0(,%eax,4) ;; Jump table!
 8048433:   90                      nop
 8048434:   8d 74 26 00             lea    0x0(%esi,%eiz,1),%esi
 8048438:   8d 45 08                lea    0x8(%ebp),%eax
 804843b:   89 04 24                mov    %eax,(%esp)
 804843e:   e8 bd ff ff ff          call   8048400 
 8048443:   8b 45 08                mov    0x8(%ebp),%eax
 8048446:   c9                      leave  

Did you try playing with optimization levels?