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Diffstat (limited to 'libffi/src/m88k/ffi.c')
| -rw-r--r-- | libffi/src/m88k/ffi.c | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/libffi/src/m88k/ffi.c b/libffi/src/m88k/ffi.c new file mode 100644 index 00000000000..68df494955e --- /dev/null +++ b/libffi/src/m88k/ffi.c @@ -0,0 +1,400 @@ +/* + * Copyright (c) 2013 Miodrag Vallat. <miod@openbsd.org> + * + * 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. + */ + +/* + * m88k Foreign Function Interface + * + * This file attempts to provide all the FFI entry points which can reliably + * be implemented in C. + * + * Only OpenBSD/m88k is currently supported; other platforms (such as + * Motorola's SysV/m88k) could be supported with the following tweaks: + * + * - non-OpenBSD systems use an `outgoing parameter area' as part of the + * 88BCS calling convention, which is not supported under OpenBSD from + * release 3.6 onwards. Supporting it should be as easy as taking it + * into account when adjusting the stack, in the assembly code. + * + * - the logic deciding whether a function argument gets passed through + * registers, or on the stack, has changed several times in OpenBSD in + * edge cases (especially for structs larger than 32 bytes being passed + * by value). The code below attemps to match the logic used by the + * system compiler of OpenBSD 5.3, i.e. gcc 3.3.6 with many m88k backend + * fixes. + */ + +#include <ffi.h> +#include <ffi_common.h> + +#include <stdlib.h> +#include <unistd.h> + +void ffi_call_OBSD (unsigned int, extended_cif *, unsigned int, void *, + void (*fn) ()); +void *ffi_prep_args (void *, extended_cif *); +void ffi_closure_OBSD (ffi_closure *); +void ffi_closure_struct_OBSD (ffi_closure *); +unsigned int ffi_closure_OBSD_inner (ffi_closure *, void *, unsigned int *, + char *); +void ffi_cacheflush_OBSD (unsigned int, unsigned int); + +#define CIF_FLAGS_INT (1 << 0) +#define CIF_FLAGS_DINT (1 << 1) + +/* + * Foreign Function Interface API + */ + +/* ffi_prep_args is called by the assembly routine once stack space has + been allocated for the function's arguments. */ + +void * +ffi_prep_args (void *stack, extended_cif *ecif) +{ + unsigned int i; + void **p_argv; + char *argp, *stackp; + unsigned int *regp; + unsigned int regused; + ffi_type **p_arg; + void *struct_value_ptr; + + regp = (unsigned int *)stack; + stackp = (char *)(regp + 8); + regused = 0; + + if (ecif->cif->rtype->type == FFI_TYPE_STRUCT + && !ecif->cif->flags) + struct_value_ptr = ecif->rvalue; + else + struct_value_ptr = NULL; + + p_argv = ecif->avalue; + + for (i = ecif->cif->nargs, p_arg = ecif->cif->arg_types; i != 0; i--, p_arg++) + { + size_t z; + unsigned short t, a; + + z = (*p_arg)->size; + t = (*p_arg)->type; + a = (*p_arg)->alignment; + + /* + * Figure out whether the argument can be passed through registers + * or on the stack. + * The rule is that registers can only receive simple types not larger + * than 64 bits, or structs the exact size of a register and aligned to + * the size of a register. + */ + if (t == FFI_TYPE_STRUCT) + { + if (z == sizeof (int) && a == sizeof (int) && regused < 8) + argp = (char *)regp; + else + argp = stackp; + } + else + { + if (z > sizeof (int) && regused < 8 - 1) + { + /* align to an even register pair */ + if (regused & 1) + { + regp++; + regused++; + } + } + if (regused < 8) + argp = (char *)regp; + else + argp = stackp; + } + + /* Enforce proper stack alignment of 64-bit types */ + if (argp == stackp && a > sizeof (int)) + { + stackp = (char *) ALIGN(stackp, a); + argp = stackp; + } + + switch (t) + { + 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; + + case FFI_TYPE_INT: + case FFI_TYPE_FLOAT: + case FFI_TYPE_UINT32: + case FFI_TYPE_SINT32: + case FFI_TYPE_POINTER: + *(unsigned int *) argp = *(unsigned int *) *p_argv; + break; + + case FFI_TYPE_DOUBLE: + case FFI_TYPE_UINT64: + case FFI_TYPE_SINT64: + case FFI_TYPE_STRUCT: + memcpy (argp, *p_argv, z); + break; + + default: + FFI_ASSERT (0); + } + + /* Align if necessary. */ + if ((sizeof (int) - 1) & z) + z = ALIGN(z, sizeof (int)); + + p_argv++; + + /* Be careful, once all registers are filled, and about to continue + on stack, regp == stackp. Therefore the check for regused as well. */ + if (argp == (char *)regp && regused < 8) + { + regp += z / sizeof (int); + regused += z / sizeof (int); + } + else + stackp += z; + } + + return struct_value_ptr; +} + +/* Perform machine dependent cif processing */ +ffi_status +ffi_prep_cif_machdep (ffi_cif *cif) +{ + /* Set the return type flag */ + switch (cif->rtype->type) + { + case FFI_TYPE_VOID: + cif->flags = 0; + break; + + case FFI_TYPE_STRUCT: + if (cif->rtype->size == sizeof (int) && + cif->rtype->alignment == sizeof (int)) + cif->flags = CIF_FLAGS_INT; + else + cif->flags = 0; + break; + + case FFI_TYPE_DOUBLE: + case FFI_TYPE_SINT64: + case FFI_TYPE_UINT64: + cif->flags = CIF_FLAGS_DINT; + break; + + default: + cif->flags = CIF_FLAGS_INT; + break; + } + + return FFI_OK; +} + +void +ffi_call (ffi_cif *cif, void (*fn) (), 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 + && (cif->rtype->size != sizeof (int) + || cif->rtype->alignment != sizeof (int))) + ecif.rvalue = alloca (cif->rtype->size); + else + ecif.rvalue = rvalue; + + switch (cif->abi) + { + case FFI_OBSD: + ffi_call_OBSD (cif->bytes, &ecif, cif->flags, ecif.rvalue, fn); + break; + + default: + FFI_ASSERT (0); + break; + } +} + +/* + * Closure API + */ + +static void +ffi_prep_closure_args_OBSD (ffi_cif *cif, void **avalue, unsigned int *regp, + char *stackp) +{ + unsigned int i; + void **p_argv; + char *argp; + unsigned int regused; + ffi_type **p_arg; + + regused = 0; + + p_argv = avalue; + + for (i = cif->nargs, p_arg = cif->arg_types; i != 0; i--, p_arg++) + { + size_t z; + unsigned short t, a; + + z = (*p_arg)->size; + t = (*p_arg)->type; + a = (*p_arg)->alignment; + + /* + * Figure out whether the argument has been passed through registers + * or on the stack. + * The rule is that registers can only receive simple types not larger + * than 64 bits, or structs the exact size of a register and aligned to + * the size of a register. + */ + if (t == FFI_TYPE_STRUCT) + { + if (z == sizeof (int) && a == sizeof (int) && regused < 8) + argp = (char *)regp; + else + argp = stackp; + } + else + { + if (z > sizeof (int) && regused < 8 - 1) + { + /* align to an even register pair */ + if (regused & 1) + { + regp++; + regused++; + } + } + if (regused < 8) + argp = (char *)regp; + else + argp = stackp; + } + + /* Enforce proper stack alignment of 64-bit types */ + if (argp == stackp && a > sizeof (int)) + { + stackp = (char *) ALIGN(stackp, a); + argp = stackp; + } + + if (z < sizeof (int) && t != FFI_TYPE_STRUCT) + *p_argv = (void *) (argp + sizeof (int) - z); + else + *p_argv = (void *) argp; + + /* Align if necessary */ + if ((sizeof (int) - 1) & z) + z = ALIGN(z, sizeof (int)); + + p_argv++; + + /* Be careful, once all registers are exhausted, and about to fetch from + stack, regp == stackp. Therefore the check for regused as well. */ + if (argp == (char *)regp && regused < 8) + { + regp += z / sizeof (int); + regused += z / sizeof (int); + } + else + stackp += z; + } +} + +unsigned int +ffi_closure_OBSD_inner (ffi_closure *closure, void *resp, unsigned int *regp, + char *stackp) +{ + ffi_cif *cif; + void **arg_area; + + cif = closure->cif; + arg_area = (void**) alloca (cif->nargs * sizeof (void *)); + + ffi_prep_closure_args_OBSD(cif, arg_area, regp, stackp); + + (closure->fun) (cif, resp, arg_area, closure->user_data); + + return cif->flags; +} + +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 int *tramp = (unsigned int *) codeloc; + void *fn; + + FFI_ASSERT (cif->abi == FFI_OBSD); + + if (cif->rtype->type == FFI_TYPE_STRUCT && !cif->flags) + fn = &ffi_closure_struct_OBSD; + else + fn = &ffi_closure_OBSD; + + /* or.u %r10, %r0, %hi16(fn) */ + tramp[0] = 0x5d400000 | (((unsigned int)fn) >> 16); + /* or.u %r13, %r0, %hi16(closure) */ + tramp[1] = 0x5da00000 | ((unsigned int)closure >> 16); + /* or %r10, %r10, %lo16(fn) */ + tramp[2] = 0x594a0000 | (((unsigned int)fn) & 0xffff); + /* jmp.n %r10 */ + tramp[3] = 0xf400c40a; + /* or %r13, %r13, %lo16(closure) */ + tramp[4] = 0x59ad0000 | ((unsigned int)closure & 0xffff); + + ffi_cacheflush_OBSD((unsigned int)codeloc, FFI_TRAMPOLINE_SIZE); + + closure->cif = cif; + closure->user_data = user_data; + closure->fun = fun; + + return FFI_OK; +} |