This is the mail archive of the
gcc-help@gcc.gnu.org
mailing list for the GCC project.
__builtin_apply issue
- From: Aurelien Buhrig <aurelien dot buhrig dot gcc at gmail dot com>
- To: gcc-help at gcc dot gnu dot org
- Date: Thu, 05 Apr 2012 17:49:42 +0200
- Subject: __builtin_apply issue
Hi,
I'm trying to make __builtin_apply work for my backend (especially
gcc.dg/torture/stackalign/builtin-apply-2.c).
My target saves unnamed args to the stack, and puts named arguments into
registers (as much as possible).
For example in the following testcase:
void foo(char *name, double d, double e, double f, int g)
{
...
}
void bar(char *name, ...)
{
__builtin_apply(foo, __builtin_apply_args(), 64);
}
In this example, foo expects first arguments to be in argument
registers, but bar arguments are into the stack (only).
expand_builtin_apply and expand_builtin_apply_args correctly copy
incoming args block from the stack to outgoing_args block (stack) and
set parameter registers as they were at the beginning of bar function,
and then call foo (using the "standard" untyped_call). But there is no
mechanism to copy incoming args from stack to argument registers.
How and where to handle such a case which seems to depend on both caller
and callee fndecl?
Thanks in advance,
Aurélien