On Tue, Jun 13, 2017 at 03:11:41PM +0300, Maxim Ostapenko wrote:
> @@ -531,11 +533,166 @@ get_mem_ref_of_assignment (const gassign *assignment,
> return true;
> }
>
> +/* Return address of last allocated dynamic alloca. */
> +
> +static tree
> +get_last_alloca_addr ()
> +{
> + if (last_alloca_addr)
> + return last_alloca_addr;
> +
> + gimple_seq seq = NULL;
> + gassign *g;
> +
> + last_alloca_addr = create_tmp_reg (ptr_type_node, "last_alloca_addr");
> +/* Insert __asan_allocas_unpoison(top, bottom) call after
> + __builtin_stackrestore(new_sp) call.
s/stackrestore/stack_restore/, that is how the builtin is called, right?
Also, please put a space before ( even in comments.
> +static void
> +handle_builtin_stackrestore (gcall *call, gimple_stmt_iterator *iter)
Again, stack_restore
> + bool alloca_with_align
> + = (DECL_FUNCTION_CODE (callee) == BUILT_IN_ALLOCA_WITH_ALIGN);
Unnecessary ()s around the comparison?
> --- a/gcc/cfgexpand.c
> +++ b/gcc/cfgexpand.c
> @@ -2241,6 +2241,10 @@ expand_used_vars (void)
> expand_stack_vars (NULL, &data);
> }
>
> + if ((flag_sanitize & SANITIZE_ADDRESS) && cfun->calls_alloca)
> + var_end_seq = asan_emit_allocas_unpoison (virtual_stack_dynamic_rtx,
> + virtual_stack_vars_rtx);
> +
Doesn't this mean the old var_end_seq is lost because of this
(in functions that call alloca, but also have addressable variables we
asan instrument)?
I'd think you need to append the sequences, or call
asan_emit_allocas_unpoison with the var_end_seq as argument and insert
it into the new sequence.
Jakub
