/* -----------------------------------------------------------------------
ffi.c - Copyright (C) 2012, 2013, 2018, 2021 Anthony Green
Moxie Foreign Function Interface
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
``Software''), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
----------------------------------------------------------------------- */
#include <ffi.h>
#include <ffi_common.h>
#include <stdlib.h>
/* ffi_prep_args is called by the assembly routine once stack space
has been allocated for the function's arguments */
void *ffi_prep_args(char *stack, extended_cif *ecif)
{
register unsigned int i;
register void **p_argv;
register char *argp;
register ffi_type **p_arg;
register int count = 0;
p_argv = ecif->avalue;
argp = stack;
if (ecif->cif->rtype->type == FFI_TYPE_STRUCT)
{
*(void **) argp = ecif->rvalue;
argp += 4;
}
for (i = ecif->cif->nargs, p_arg = ecif->cif->arg_types;
(i != 0);
i--, p_arg++)
{
size_t z;
z = (*p_arg)->size;
if ((*p_arg)->type == FFI_TYPE_STRUCT)
{
z = sizeof(void*);
*(void **) argp = *p_argv;
}
else if (z < sizeof(int))
{
z = sizeof(int);
switch ((*p_arg)->type)
{
case FFI_TYPE_SINT8:
*(signed int *) argp = (signed int)*(SINT8 *)(* p_argv);
break;
case FFI_TYPE_UINT8:
*(unsigned int *) argp = (unsigned int)*(UINT8 *)(* p_argv);
break;
case FFI_TYPE_SINT16:
*(signed int *) argp = (signed int)*(SINT16 *)(* p_argv);
break;
case FFI_TYPE_UINT16:
*(unsigned int *) argp = (unsigned int)*(UINT16 *)(* p_argv);
break;
default:
FFI_ASSERT(0);
}
}
else if (z == sizeof(int))
{
*(unsigned int *) argp = (unsigned int)*(UINT32 *)(* p_argv);
}
else
{
memcpy(argp, *p_argv, z);
}
p_argv++;
argp += z;
count += z;
}
return (stack + ((count > 24) ? 24 : FFI_ALIGN_DOWN(count, 8)));
}
/* Perform machine dependent cif processing */
ffi_status ffi_prep_cif_machdep(ffi_cif *cif)
{
if (cif->rtype->type == FFI_TYPE_STRUCT)
cif->flags = -1;
else
cif->flags = cif->rtype->size;
cif->bytes = FFI_ALIGN (cif->bytes, 8);
return FFI_OK;
}
extern void ffi_call_EABI(void *(*)(char *, extended_cif *),
extended_cif *,
unsigned, unsigned,
unsigned *,
void (*fn)(void));
void ffi_call(ffi_cif *cif,
void (*fn)(void),
void *rvalue,
void **avalue)
{
extended_cif ecif;
ecif.cif = cif;
ecif.avalue = avalue;
/* If the return value is a struct and we don't have a return */
/* value address then we need to make one */
if ((rvalue == NULL) &&
(cif->rtype->type == FFI_TYPE_STRUCT))
{
ecif.rvalue = alloca(cif->rtype->size);
}
else
ecif.rvalue = rvalue;
switch (cif->abi)
{
case FFI_EABI:
ffi_call_EABI(ffi_prep_args, &ecif, cif->bytes,
cif->flags, ecif.rvalue, fn);
break;
default:
FFI_ASSERT(0);
break;
}
}
void ffi_closure_eabi (unsigned arg1, unsigned arg2, unsigned arg3,
unsigned arg4, unsigned arg5, unsigned arg6)
{
/* This function is called by a trampoline. The trampoline stows a
pointer to the ffi_closure object in $r12. We must save this
pointer in a place that will persist while we do our work. */
register ffi_closure *creg __asm__ ("$r12");
ffi_closure *closure = creg;
/* Arguments that don't fit in registers are found on the stack
at a fixed offset above the current frame pointer. */
register char *frame_pointer __asm__ ("$fp");
/* Pointer to a struct return value. */
void *struct_rvalue = (void *) arg1;
/* 6 words reserved for register args + 3 words from jsr */
char *stack_args = frame_pointer + 9*4;
/* Lay the register arguments down in a continuous chunk of memory. */
unsigned register_args[6] =
{ arg1, arg2, arg3, arg4, arg5, arg6 };
char *register_args_ptr = (char *) register_args;
ffi_cif *cif = closure->cif;
ffi_type **arg_types = cif->arg_types;
void **avalue = alloca (cif->nargs * sizeof(void *));
char *ptr = (char *) register_args;
int i;
/* preserve struct type return pointer passing */
if ((cif->rtype != NULL) && (cif->rtype->type == FFI_TYPE_STRUCT)) {
ptr += 4;
register_args_ptr = (char *)®ister_args[1];
}
/* Find the address of each argument. */
for (i = 0; i < cif->nargs; i++)
{
switch (arg_types[i]->type)
{
case FFI_TYPE_SINT8:
case FFI_TYPE_UINT8:
avalue[i] = ptr + 3;
break;
case FFI_TYPE_SINT16:
case FFI_TYPE_UINT16:
avalue[i] = ptr + 2;
break;
case FFI_TYPE_SINT32:
case FFI_TYPE_UINT32:
case FFI_TYPE_FLOAT:
case FFI_TYPE_POINTER:
avalue[i] = ptr;
break;
case FFI_TYPE_STRUCT:
{
if (arg_types[i]->type->size > 4)
{
void *copy = alloca(arg_types[i]->type->size);
memcpy(copy, *(void**)ptr, arg_types[i]->type->size);
avalue[i] = copy;
}
else
avalue[i] = *(void**)ptr;
}
break;
default:
/* This is an 8-byte value. */
if (ptr == (char *) ®ister_args[5])
{
/* The value is split across two locations */
unsigned *ip = alloca(8);
avalue[i] = ip;
ip[0] = *(unsigned *) ptr;
ip[1] = *(unsigned *) stack_args;
}
else
{
avalue[i] = ptr;
}
ptr += 4;
break;
}
ptr += 4;
/* If we've handled more arguments than fit in registers,
start looking at the those passed on the stack. */
if (ptr == (char *) ®ister_args[6])
ptr = stack_args;
else if (ptr == (char *) ®ister_args[7])
ptr = stack_args + 4;
}
/* Invoke the closure. */
if (cif->rtype && (cif->rtype->type == FFI_TYPE_STRUCT))
{
(closure->fun) (cif, struct_rvalue, avalue, closure->user_data);
}
else
{
/* Allocate space for the return value and call the function. */
long long rvalue;
(closure->fun) (cif, &rvalue, avalue, closure->user_data);
asm ("mov $r12, %0\n ld.l $r0, ($r12)\n ldo.l $r1, 4($r12)" : : "r" (&rvalue));
}
}
ffi_status
ffi_prep_closure_loc (ffi_closure* closure,
ffi_cif* cif,
void (*fun)(ffi_cif*, void*, void**, void*),
void *user_data,
void *codeloc)
{
unsigned short *tramp = (unsigned short *) &closure->tramp[0];
unsigned long fn = (long) ffi_closure_eabi;
unsigned long cls = (long) codeloc;
if (cif->abi != FFI_EABI)
return FFI_BAD_ABI;
fn = (unsigned long) ffi_closure_eabi;
tramp[0] = 0x01e0; /* ldi.l $r12, .... */
tramp[1] = cls >> 16;
tramp[2] = cls & 0xffff;
tramp[3] = 0x1a00; /* jmpa .... */
tramp[4] = fn >> 16;
tramp[5] = fn & 0xffff;
closure->cif = cif;
closure->fun = fun;
closure->user_data = user_data;
return FFI_OK;
}
