[Valgrind-developers] Re: stacks and ThreadStates

[Jeremy F. <je...@go...>]

Nicholas Nethercote wrote:

> struct ThreadState includes the following fields:
>
>    UInt stack_size;
>    Addr stack_base;
>    Addr stack_highest_word;
>
> struct os_state_t (for linux) includes the following fields:
>
>    UInt *stack;                 /* stack base */
>    UInt stacksize;              /* stack size in UInts */
>
> Is there some overlap here that could be removed?  AFAICT, 
> ThreadState.stack_base is not used in any meaningful way and could be 
> removed.  Is one of these stacks for Valgrind and the other for the 
> client?  It's unclear from the field names. 

Yeah, the os_state ones are the Valgrind internal stack, and the ones in 
ThreadState are the client stack.  ThreadState.stack_base probably isn't 
meaningful because we don't allocate client stacks and the useful range 
for a stack is between the stackpointer and the top.

So: both sets are needed, but their meanings clarified; stack_base can go.

    J