Re: [Qemu-devel] help with helper functions

[Peter Maydell]

On 19 March 2012 22:34, João Corrêa <address@hidden> wrote:
> I'm trying to use some helper functions to instrument translated code, but
> I'm getting some segfaults while doing it. Here are some code I've placed:
>
> target-i386/helper.h
> DEF_HELPER_1(foo, void, tl)
>
> target-i386/op_helper.c
> #ifdef TARGET_X86_64
>
> void foo(target_ulong t0){

Should be
HELPER(foo)(target_ulong t0) {

> }
>
> target-i386/translate.c
> static inline void gen_jmp_im(target_ulong pc){
>     #ifdef TARGET_X86_64
>     printf("test2\n");
>     gen_foo(pc);

should be gen_helper_foo().

But your main problem here is that gen_helper_*() take TCGv
types (TCG values), not immediate constants. You need to emit
TCG code to load 'pc' into a TCG temporary first.

If you configure --enable-debug then it ought to put in some
extra typechecking code which will make this fail compilation.

-- PMM