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#include <stdio.h>
extern void ffi_closure_SYSV(void);
/* whoops: abi states only certain register pairs
* can be used for passing long long int
* specifically (r3,r4), (r5,r6), (r7,r8),
* (r9,r10) and if next arg is long long but
* not correct starting register of pair then skip
* until the proper starting register
*/
if (intarg_count%2 != 0)
{
intarg_count ++;
gpr_base++;
}
static void flush_icache(char *, int);
ffi_status
ffi_prep_closure (ffi_closure* closure,
ffi_cif* cif,
void (*fun)(ffi_cif*, void*, void**, void*),
void *user_data)
{
unsigned int *tramp;
FFI_ASSERT (cif->abi == FFI_GCC_SYSV);
tramp = (unsigned int *) &closure->tramp[0];
tramp[0] = 0x7c0802a6; /* mflr r0 */
tramp[1] = 0x4800000d; /* bl 10 <trampoline_initial+0x10> */
tramp[4] = 0x7d6802a6; /* mflr r11 */
tramp[5] = 0x7c0803a6; /* mtlr r0 */
tramp[6] = 0x800b0000; /* lwz r0,0(r11) */
tramp[7] = 0x816b0004; /* lwz r11,4(r11) */
tramp[8] = 0x7c0903a6; /* mtctr r0 */
tramp[9] = 0x4e800420; /* bctr */
*(void **) &tramp[2] = (void *)ffi_closure_SYSV; /* function */
*(void **) &tramp[3] = (void *)closure; /* context */
closure->cif = cif;
closure->fun = fun;
closure->user_data = user_data;
/* Flush the icache. */
flush_icache(&closure->tramp[0],FFI_TRAMPOLINE_SIZE);
return FFI_OK;
}
#define MIN_CACHE_LINE_SIZE 8
static void flush_icache(char * addr1, int size)
{
int i;
char * addr;
for (i = 0; i < size; i += MIN_CACHE_LINE_SIZE) {
addr = addr1 + i;
__asm__ volatile ("icbi 0,%0;" "dcbf 0,%0;" : : "r"(addr) : "memory");
}
addr = addr1 + size - 1;
__asm__ volatile ("icbi 0,%0;" "dcbf 0,%0;" "sync;" "isync;" : : "r"(addr) : "memory");
}
int ffi_closure_helper_SYSV (ffi_closure*, void*, unsigned long*,
unsigned long*, unsigned long*);
/* Basically the trampoline invokes ffi_closure_SYSV, and on
* entry, r11 holds the address of the closure.
* After storing the registers that could possibly contain
* parameters to be passed into the stack frame and setting
* up space for a return value, ffi_closure_SYSV invokes the
* following helper function to do most of the work
*/
int
ffi_closure_helper_SYSV (ffi_closure* closure, void * rvalue,
unsigned long * pgr, unsigned long * pfr,
unsigned long * pst)
{
/* rvalue is the pointer to space for return value in closure assembly */
/* pgr is the pointer to where r3-r10 are stored in ffi_closure_SYSV */
/* pfr is the pointer to where f1-f8 are stored in ffi_closure_SYSV */
/* pst is the pointer to outgoing parameter stack in original caller */
void ** avalue;
ffi_type ** arg_types;
long i, avn;
long nf; /* number of floating registers already used */
long ng; /* number of general registers already used */
ffi_cif * cif;
double temp;
cif = closure->cif;
avalue = alloca(cif->nargs * sizeof(void *));
nf = 0;
ng = 0;
/* Copy the caller's structure return value address so that the closure
returns the data directly to the caller. */
if (cif->rtype->type == FFI_TYPE_STRUCT)
{
rvalue = *pgr;
ng++;
pgr++;
}
i = 0;
avn = cif->nargs;
arg_types = cif->arg_types;
/* Grab the addresses of the arguments from the stack frame. */
while (i < avn)
{
switch (arg_types[i]->type)
{
case FFI_TYPE_SINT8:
case FFI_TYPE_UINT8:
/* there are 8 gpr registers used to pass values */
if (ng < 8) {
avalue[i] = (((char *)pgr)+3);
ng++;
pgr++;
} else {
avalue[i] = (((char *)pst)+3);
pst++;
}
break;
case FFI_TYPE_SINT16:
case FFI_TYPE_UINT16:
/* there are 8 gpr registers used to pass values */
if (ng < 8) {
avalue[i] = (((char *)pgr)+2);
ng++;
pgr++;
} else {
avalue[i] = (((char *)pst)+2);
pst++;
}
break;
case FFI_TYPE_SINT32:
case FFI_TYPE_UINT32:
case FFI_TYPE_POINTER:
case FFI_TYPE_STRUCT:
/* there are 8 gpr registers used to pass values */
if (ng < 8) {
avalue[i] = pgr;
ng++;
pgr++;
} else {
avalue[i] = pst;
pst++;
}
break;
case FFI_TYPE_SINT64:
case FFI_TYPE_UINT64:
/* passing long long ints are complex, they must
* be passed in suitable register pairs such as
* (r3,r4) or (r5,r6) or (r6,r7), or (r7,r8) or (r9,r10)
* and if the entire pair aren't available then the outgoing
* parameter stack is used for both but an alignment of 8
* must will be kept. So we must either look in pgr
* or pst to find the correct address for this type
* of parameter.
*/
if (ng < 7) {
if (ng & 0x01) {
/* skip r4, r6, r8 as starting points */
ng++;
pgr++;
}
avalue[i] = pgr;
ng+=2;
pgr+=2;
} else {
if (((long)pst) & 4) pst++;
avalue[i] = pst;
pst+=2;
}
break;
case FFI_TYPE_FLOAT:
/* unfortunately float values are stored as doubles
* in the ffi_closure_SYSV code (since we don't check
* the type in that routine). This is also true
* of floats passed on the outgoing parameter stack.
* Also, on the outgoing stack all values are aligned
* to 8
*
* Don't you just love the simplicity of this ABI!
*/
/* there are 8 64bit floating point registers */
if (nf < 8) {
temp = *(double*)pfr;
*(float*)pfr = (float)temp;
avalue[i] = pfr;
nf++;
pfr+=2;
} else {
/* FIXME? here we are really changing the values
* stored in the original calling routines outgoing
* parameter stack. This is probably a really
* naughty thing to do but...
*/
if (((long)pst) & 4) pst++;
temp = *(double*)pst;
*(float*)pst = (float)temp;
avalue[i] = pst;
nf++;
pst+=2;
}
break;
case FFI_TYPE_DOUBLE:
/* On the outgoing stack all values are aligned to 8 */
/* there are 8 64bit floating point registers */
if (nf < 8) {
avalue[i] = pfr;
nf++;
pfr+=2;
} else {
if (((long)pst) & 4) pst++;
avalue[i] = pst;
nf++;
pst+=2;
}
break;
default:
FFI_ASSERT(0);
}
i++;
}
(closure->fun) (cif, rvalue, avalue, closure->user_data);
/* Tell ffi_closure_osf how to perform return type promotions. */
return cif->rtype->type;
}
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