On 24 December 2015 at 22:19, farmdve <farm...@gmail.com> wrote: > I've been looking and looking, but it must be defined via a macro, > I wish to see it's members.
There is no such struct definition. The TCGv_i32, TCGv_i64, etc types are defined as pointers to structs like this so that we get some type-checking from the compiler that prevents target-* code from accidentally passing a TCGv_i64 to a function expecting a TCGv_i32 and so on. However the underlying representation of a TCGv is just an integer (it's an index into the TCG code generator's array of temporaries). Whenever the TCG code hands out a TCGv it goes via one of the MAKE_TCGV* functions which converts an integer into the appropriate type, and when the target-* code passes it a TCGv_i32 etc type it goes via one of the GET_TCGV_* functions to get it back as an integer again. Since this small number is not a valid pointer it's never valid to try to dereference a TCGv_. The underlying representation of the TCGv* types is opaque to the guest-cpu-specific code in target-*. We used to use either (a) real plain integer types or (b) structs which were different between the three types; the current approach was introduced in commit b6c73a6d45b63926 and provides the efficiency of handing around int types with the type checking that the struct approach had. But most code never cared about the representation; you can see that commit only really changed the GET and MAKE functions. thanks -- PMM
