+++ /dev/null
-/* -----------------------------------------------------------------------
- ffi.c - Copyright (c) 1998 Geoffrey Keating
-
- PowerPC Foreign Function Interface
-
- $Id: ffi.c,v 1.1.1.1 1998/11/29 16:48:16 green Exp $
-
- 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 AUTHOR 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>
-#include <stdio.h>
-
-extern void ffi_closure_SYSV(void);
-
-enum {
- /* The assembly depends on these exact flags. */
- FLAG_RETURNS_NOTHING = 1 << (31-30), /* These go in cr7 */
- FLAG_RETURNS_FP = 1 << (31-29),
- FLAG_RETURNS_64BITS = 1 << (31-28),
-
- FLAG_ARG_NEEDS_COPY = 1 << (31- 7),
- FLAG_FP_ARGUMENTS = 1 << (31- 6), /* cr1.eq; specified by ABI */
- FLAG_4_GPR_ARGUMENTS = 1 << (31- 5),
- FLAG_RETVAL_REFERENCE = 1 << (31- 4)
-};
-
-/* About the SYSV ABI. */
-enum {
- NUM_GPR_ARG_REGISTERS = 8,
- NUM_FPR_ARG_REGISTERS = 8
-};
-enum { ASM_NEEDS_REGISTERS = 4 };
-
-/* ffi_prep_args is called by the assembly routine once stack space
- has been allocated for the function's arguments.
-
- The stack layout we want looks like this:
-
- | Return address from ffi_call_SYSV 4bytes | higher addresses
- |--------------------------------------------|
- | Previous backchain pointer 4 | stack pointer here
- |--------------------------------------------|<+ <<< on entry to
- | Saved r28-r31 4*4 | | ffi_call_SYSV
- |--------------------------------------------| |
- | GPR registers r3-r10 8*4 | | ffi_call_SYSV
- |--------------------------------------------| |
- | FPR registers f1-f8 (optional) 8*8 | |
- |--------------------------------------------| | stack |
- | Space for copied structures | | grows |
- |--------------------------------------------| | down V
- | Parameters that didn't fit in registers | |
- |--------------------------------------------| | lower addresses
- | Space for callee's LR 4 | |
- |--------------------------------------------| | stack pointer here
- | Current backchain pointer 4 |-/ during
- |--------------------------------------------| <<< ffi_call_SYSV
-
- */
-
-/*@-exportheader@*/
-void ffi_prep_args(extended_cif *ecif, unsigned *const stack)
-/*@=exportheader@*/
-{
- const unsigned bytes = ecif->cif->bytes;
- const unsigned flags = ecif->cif->flags;
-
- /* 'stacktop' points at the previous backchain pointer. */
- unsigned *const stacktop = stack + (ecif->cif->bytes / sizeof(unsigned));
-
- /* 'gpr_base' points at the space for gpr3, and grows upwards as
- we use GPR registers. */
- unsigned *gpr_base = stacktop - ASM_NEEDS_REGISTERS - NUM_GPR_ARG_REGISTERS;
- int intarg_count = 0;
-
- /* 'fpr_base' points at the space for fpr1, and grows upwards as
- we use FPR registers. */
- double *fpr_base = (double *)gpr_base - NUM_FPR_ARG_REGISTERS;
- int fparg_count = 0;
-
- /* 'copy_space' grows down as we put structures in it. It should
- stay 16-byte aligned. */
- char *copy_space = ((flags & FLAG_FP_ARGUMENTS)
- ? (char *)fpr_base
- : (char *)gpr_base);
-
- /* 'next_arg' grows up as we put parameters in it. */
- unsigned *next_arg = stack + 2;
-
- int i;
- ffi_type **ptr;
- double double_tmp;
- void **p_argv;
- size_t struct_copy_size;
- unsigned gprvalue;
-
- /* Check that everything starts aligned properly. */
- FFI_ASSERT(((unsigned)(char *)stack & 0xF) == 0);
- FFI_ASSERT(((unsigned)(char *)copy_space & 0xF) == 0);
- FFI_ASSERT(((unsigned)(char *)stacktop & 0xF) == 0);
- FFI_ASSERT((bytes & 0xF) == 0);
- FFI_ASSERT(copy_space >= (char *)next_arg);
-
- /* Deal with return values that are actually pass-by-reference. */
- if (flags & FLAG_RETVAL_REFERENCE)
- {
- *gpr_base++ = (unsigned)(char *)ecif->rvalue;
- intarg_count++;
- }
-
- /* Now for the arguments. */
- p_argv = ecif->avalue;
- for (ptr = ecif->cif->arg_types, i = ecif->cif->nargs;
- i > 0;
- i--, ptr++, p_argv++)
- {
- switch ((*ptr)->type)
- {
- case FFI_TYPE_FLOAT:
- double_tmp = *(float *)*p_argv;
- if (fparg_count >= NUM_FPR_ARG_REGISTERS)
- {
- *(float *)next_arg = (float)double_tmp;
- next_arg += 1;
- }
- else
- *fpr_base++ = double_tmp;
- fparg_count++;
- FFI_ASSERT(flags & FLAG_FP_ARGUMENTS);
- break;
-
- case FFI_TYPE_DOUBLE:
- double_tmp = *(double *)*p_argv;
-
- if (fparg_count >= NUM_FPR_ARG_REGISTERS)
- {
- if (intarg_count%2 != 0)
- {
- intarg_count++;
- next_arg++;
- }
- *(double *)next_arg = double_tmp;
- next_arg += 2;
- }
- else
- *fpr_base++ = double_tmp;
- fparg_count++;
- FFI_ASSERT(flags & FLAG_FP_ARGUMENTS);
- break;
-
- case FFI_TYPE_UINT64:
- case FFI_TYPE_SINT64:
- if (intarg_count == NUM_GPR_ARG_REGISTERS-1)
- intarg_count++;
- if (intarg_count >= NUM_GPR_ARG_REGISTERS)
- {
- if (intarg_count%2 != 0)
- {
- intarg_count++;
- next_arg++;
- }
- *(long long *)next_arg = *(long long *)*p_argv;
- next_arg += 2;
- }
- else
- {
- /* 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++;
- }
- *(long long *)gpr_base = *(long long *)*p_argv;
- gpr_base += 2;
- }
- intarg_count += 2;
- break;
-
- case FFI_TYPE_STRUCT:
-#if FFI_TYPE_LONGDOUBLE != FFI_TYPE_DOUBLE
- case FFI_TYPE_LONGDOUBLE:
-#endif
- struct_copy_size = ((*ptr)->size + 15) & ~0xF;
- copy_space -= struct_copy_size;
- memcpy(copy_space, (char *)*p_argv, (*ptr)->size);
-
- gprvalue = (unsigned)copy_space;
-
- FFI_ASSERT(copy_space > (char *)next_arg);
- FFI_ASSERT(flags & FLAG_ARG_NEEDS_COPY);
- goto putgpr;
-
- case FFI_TYPE_UINT8:
- gprvalue = *(unsigned char *)*p_argv;
- goto putgpr;
- case FFI_TYPE_SINT8:
- gprvalue = *(signed char *)*p_argv;
- goto putgpr;
- case FFI_TYPE_UINT16:
- gprvalue = *(unsigned short *)*p_argv;
- goto putgpr;
- case FFI_TYPE_SINT16:
- gprvalue = *(signed short *)*p_argv;
- goto putgpr;
-
- case FFI_TYPE_INT:
- case FFI_TYPE_UINT32:
- case FFI_TYPE_SINT32:
- case FFI_TYPE_POINTER:
- gprvalue = *(unsigned *)*p_argv;
- putgpr:
- if (intarg_count >= NUM_GPR_ARG_REGISTERS)
- *next_arg++ = gprvalue;
- else
- *gpr_base++ = gprvalue;
- intarg_count++;
- break;
- }
- }
-
- /* Check that we didn't overrun the stack... */
- FFI_ASSERT(copy_space >= (char *)next_arg);
- FFI_ASSERT(gpr_base <= stacktop - ASM_NEEDS_REGISTERS);
- FFI_ASSERT((unsigned *)fpr_base
- <= stacktop - ASM_NEEDS_REGISTERS - NUM_GPR_ARG_REGISTERS);
- FFI_ASSERT(flags & FLAG_4_GPR_ARGUMENTS || intarg_count <= 4);
-}
-
-/* Perform machine dependent cif processing */
-ffi_status ffi_prep_cif_machdep(ffi_cif *cif)
-{
- /* All this is for the SYSV ABI. */
- int i;
- ffi_type **ptr;
- unsigned bytes;
- int fparg_count = 0, intarg_count = 0;
- unsigned flags = 0;
- unsigned struct_copy_size = 0;
-
- /* All the machine-independent calculation of cif->bytes will be wrong.
- Redo the calculation for SYSV. */
-
- /* Space for the frame pointer, callee's LR, and the asm's temp regs. */
- bytes = (2 + ASM_NEEDS_REGISTERS) * sizeof(int);
-
- /* Space for the GPR registers. */
- bytes += NUM_GPR_ARG_REGISTERS * sizeof(int);
-
- /* Return value handling. The rules are as follows:
- - 32-bit (or less) integer values are returned in gpr3;
- - Structures of size <= 4 bytes also returned in gpr3;
- - 64-bit integer values and structures between 5 and 8 bytes are returned
- in gpr3 and gpr4;
- - Single/double FP values are returned in fpr1;
- - Larger structures and long double (if not equivalent to double) values
- are allocated space and a pointer is passed as the first argument. */
- switch (cif->rtype->type)
- {
- case FFI_TYPE_DOUBLE:
- flags |= FLAG_RETURNS_64BITS;
- /* Fall through. */
- case FFI_TYPE_FLOAT:
- flags |= FLAG_RETURNS_FP;
- break;
-
- case FFI_TYPE_UINT64:
- case FFI_TYPE_SINT64:
- flags |= FLAG_RETURNS_64BITS;
- break;
-
- case FFI_TYPE_STRUCT:
- if (cif->abi != FFI_GCC_SYSV)
- if (cif->rtype->size <= 4)
- break;
- else if (cif->rtype->size <= 8)
- {
- flags |= FLAG_RETURNS_64BITS;
- break;
- }
- /* else fall through. */
-#if FFI_TYPE_LONGDOUBLE != FFI_TYPE_DOUBLE
- case FFI_TYPE_LONGDOUBLE:
-#endif
- intarg_count++;
- flags |= FLAG_RETVAL_REFERENCE;
- /* Fall through. */
- case FFI_TYPE_VOID:
- flags |= FLAG_RETURNS_NOTHING;
- break;
-
- default:
- /* Returns 32-bit integer, or similar. Nothing to do here. */
- break;
- }
-
- /* The first NUM_GPR_ARG_REGISTERS words of integer arguments, and the
- first NUM_FPR_ARG_REGISTERS fp arguments, go in registers; the rest
- goes on the stack. Structures and long doubles (if not equivalent
- to double) are passed as a pointer to a copy of the structure.
- Stuff on the stack needs to keep proper alignment. */
- for (ptr = cif->arg_types, i = cif->nargs; i > 0; i--, ptr++)
- {
- switch ((*ptr)->type)
- {
- case FFI_TYPE_FLOAT:
- fparg_count++;
- /* floating singles are not 8-aligned on stack */
- break;
-
- case FFI_TYPE_DOUBLE:
- fparg_count++;
- /* If this FP arg is going on the stack, it must be
- 8-byte-aligned. */
- if (fparg_count > NUM_FPR_ARG_REGISTERS
- && intarg_count%2 != 0)
- intarg_count++;
- break;
-
- case FFI_TYPE_UINT64:
- case FFI_TYPE_SINT64:
- /* 'long long' arguments are passed as two words, but
- either both words must fit in registers or both go
- on the stack. If they go on the stack, they must
- be 8-byte-aligned. */
- if (intarg_count == NUM_GPR_ARG_REGISTERS-1
- || intarg_count >= NUM_GPR_ARG_REGISTERS && intarg_count%2 != 0)
- intarg_count++;
- intarg_count += 2;
- break;
-
- case FFI_TYPE_STRUCT:
-#if FFI_TYPE_LONGDOUBLE != FFI_TYPE_DOUBLE
- case FFI_TYPE_LONGDOUBLE:
-#endif
- /* We must allocate space for a copy of these to enforce
- pass-by-value. Pad the space up to a multiple of 16
- bytes (the maximum alignment required for anything under
- the SYSV ABI). */
- struct_copy_size += ((*ptr)->size + 15) & ~0xF;
- /* Fall through (allocate space for the pointer). */
-
- default:
- /* Everything else is passed as a 4-byte word in a GPR, either
- the object itself or a pointer to it. */
- intarg_count++;
- break;
- }
- }
-
- if (fparg_count != 0)
- flags |= FLAG_FP_ARGUMENTS;
- if (intarg_count > 4)
- flags |= FLAG_4_GPR_ARGUMENTS;
- if (struct_copy_size != 0)
- flags |= FLAG_ARG_NEEDS_COPY;
-
- /* Space for the FPR registers, if needed. */
- if (fparg_count != 0)
- bytes += NUM_FPR_ARG_REGISTERS * sizeof(double);
-
- /* Stack space. */
- if (intarg_count > NUM_GPR_ARG_REGISTERS)
- bytes += (intarg_count - NUM_GPR_ARG_REGISTERS) * sizeof(int);
- if (fparg_count > NUM_FPR_ARG_REGISTERS)
- bytes += (fparg_count - NUM_FPR_ARG_REGISTERS) * sizeof(double);
-
- /* The stack space allocated needs to be a multiple of 16 bytes. */
- bytes = (bytes + 15) & ~0xF;
-
- /* Add in the space for the copied structures. */
- bytes += struct_copy_size;
-
- cif->flags = flags;
- cif->bytes = bytes;
-
- return FFI_OK;
-}
-
-/*@-declundef@*/
-/*@-exportheader@*/
-extern void ffi_call_SYSV(/*@out@*/ extended_cif *,
- unsigned, unsigned,
- /*@out@*/ unsigned *,
- void (*fn)());
-/*@=declundef@*/
-/*@=exportheader@*/
-
-void ffi_call(/*@dependent@*/ ffi_cif *cif,
- void (*fn)(),
- /*@out@*/ void *rvalue,
- /*@dependent@*/ 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))
- {
- /*@-sysunrecog@*/
- ecif.rvalue = alloca(cif->rtype->size);
- /*@=sysunrecog@*/
- }
- else
- ecif.rvalue = rvalue;
-
-
- switch (cif->abi)
- {
- case FFI_SYSV:
- case FFI_GCC_SYSV:
- /*@-usedef@*/
- ffi_call_SYSV(&ecif, -cif->bytes,
- cif->flags, ecif.rvalue, fn);
- /*@=usedef@*/
- break;
- default:
- FFI_ASSERT(0);
- break;
- }
-}
-
-
-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).
- */
-
- /* 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...
- */
- avalue[i] = pst;
- nf++;
- pst+=1;
- }
- 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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