On Fri, Jun 14, 2019 at 8:31 AM Richard Sandiford
<richard.sandif...@arm.com> wrote:
>
> "H.J. Lu" <hjl.to...@gmail.com> writes:
> > diff --git a/gcc/calls.c b/gcc/calls.c
> > index c8a42680041..6ab138e7bb0 100644
> > --- a/gcc/calls.c
> > +++ b/gcc/calls.c
> > @@ -3226,6 +3226,19 @@ can_implement_as_sibling_call_p (tree exp,
> > return true;
> > }
> >
> > +/* Update stack alignment when the parameter is passed in the stack
> > + since the outgoing parameter requires extra alignment on the calling
> > + function side. */
> > +
> > +static void
> > +update_stack_alignment_for_call (struct locate_and_pad_arg_data *locate)
> > +{
> > + if (crtl->stack_alignment_needed < locate->boundary)
> > + crtl->stack_alignment_needed = locate->boundary;
> > + if (crtl->preferred_stack_boundary < locate->boundary)
> > + crtl->preferred_stack_boundary = locate->boundary;
> > +}
> > +
> > /* Generate all the code for a CALL_EXPR exp
> > and return an rtx for its value.
> > Store the value in TARGET (specified as an rtx) if convenient.
> > @@ -3703,6 +3716,12 @@ expand_call (tree exp, rtx target, int ignore)
> > /* Ensure current function's preferred stack boundary is at least
> > what we need. Stack alignment may also increase preferred stack
> > boundary. */
> > + for (i = 0; i < num_actuals; i++)
> > + if (reg_parm_stack_space > 0
> > + || args[i].reg == 0
> > + || args[i].partial != 0
> > + || args[i].pass_on_stack)
> > + update_stack_alignment_for_call (&args[i].locate);
> > if (crtl->preferred_stack_boundary < preferred_stack_boundary)
> > crtl->preferred_stack_boundary = preferred_stack_boundary;
> > else
> > @@ -4961,6 +4980,12 @@ emit_library_call_value_1 (int retval, rtx orgfun,
> > rtx value,
> > targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0,
> > true);
> > }
> >
> > + for (int i = 0; i < nargs; i++)
> > + if (reg_parm_stack_space > 0
> > + || argvec[i].reg == 0
> > + || argvec[i].partial != 0)
> > + update_stack_alignment_for_call (&argvec[i].locate);
> > +
>
> It's safe to test argvec[i].pass_on_stack here too, since the vector
There is no pass_on_stack in argvec:
struct arg
{
rtx value;
machine_mode mode;
rtx reg;
int partial;
struct locate_and_pad_arg_data locate;
rtx save_area;
};
struct arg *argvec;
> is initialised to zeros. So I think we should move the "if"s into the
> new function:
>
> static void
> update_stack_alignment_for_call (struct locate_and_pad_arg_data *locate)
> {
> if (reg_parm_stack_space > 0
> || locate->reg == 0
> || locate->partial != 0
> || locate->pass_on_stack)
Since we have
struct locate_and_pad_arg_data
{
/* Size of this argument on the stack, rounded up for any padding it
gets. If REG_PARM_STACK_SPACE is defined, then register parms are
counted here, otherwise they aren't. */
struct args_size size;
/* Offset of this argument from beginning of stack-args. */
struct args_size offset;
/* Offset to the start of the stack slot. Different from OFFSET
if this arg pads downward. */
struct args_size slot_offset;
/* The amount that the stack pointer needs to be adjusted to
force alignment for the next argument. */
struct args_size alignment_pad;
/* Which way we should pad this arg. */
pad_direction where_pad;
/* slot_offset is at least this aligned. */
unsigned int boundary;
};
we can't check reg, partial nor pass_on_stack here.
> {
> if (crtl->stack_alignment_needed < locate->boundary)
> crtl->stack_alignment_needed = locate->boundary;
> if (crtl->preferred_stack_boundary < locate->boundary)
> crtl->preferred_stack_boundary = locate->boundary;
> }
> }
>
> OK with that change, thanks.
>
Is my original patch OK?
Thanks.
--
H.J.
