------- Comment #11 from ktietz at gcc dot gnu dot org 2009-07-06 16:12 -------
(In reply to comment #10)
> > Well, why? For save or called saved registers the functions
> > epilogue/prologue
> > takes care. The reason why gcc tries to choose ebx for call address register
> > here, is exactly this reason, as it can be sure that after the sibcall, the
> > register is still valid.
>
> What's the assembly code generated with your patch?
>
Compiling the test case with -O2
.file "c_impfast.c"
.text
.p2align 4,,15
.globl _f
.def _f; .scl 2; .type 32; .endef
_f:
pushl %ebp
movl $2, %ecx
movl %esp, %ebp
pushl %ebx
subl $4, %esp
movl __i...@h@4, %ebx
call *%ebx
addl $4, %esp
movl $1, %ecx
popl %ebx
popl %ebp
jmp *%ebx
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38900
