diff options
Diffstat (limited to 'ext/ffi_c/libffi/src/microblaze/ffi.c')
| -rw-r--r-- | ext/ffi_c/libffi/src/microblaze/ffi.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/ext/ffi_c/libffi/src/microblaze/ffi.c b/ext/ffi_c/libffi/src/microblaze/ffi.c new file mode 100644 index 0000000..ea962ea --- /dev/null +++ b/ext/ffi_c/libffi/src/microblaze/ffi.c @@ -0,0 +1,321 @@ +/* ----------------------------------------------------------------------- + ffi.c - Copyright (c) 2012, 2013 Xilinx, Inc + + MicroBlaze 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> + +extern void ffi_call_SYSV(void (*)(void*, extended_cif*), extended_cif*, + unsigned int, unsigned int, unsigned int*, void (*fn)(void), + unsigned int, unsigned int); + +extern void ffi_closure_SYSV(void); + +#define WORD_SIZE sizeof(unsigned int) +#define ARGS_REGISTER_SIZE (WORD_SIZE * 6) +#define WORD_ALIGN(x) ALIGN(x, WORD_SIZE) + +/* 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; + ffi_type** p_arg; + void** p_argv; + void* stack_args_p = stack; + + p_argv = ecif->avalue; + + if (ecif == NULL || ecif->cif == NULL) { + return; /* no description to prepare */ + } + + if ((ecif->cif->rtype != NULL) && + (ecif->cif->rtype->type == FFI_TYPE_STRUCT)) + { + /* if return type is a struct which is referenced on the stack/reg5, + * by a pointer. Stored the return value pointer in r5. + */ + char* addr = stack_args_p; + memcpy(addr, &(ecif->rvalue), WORD_SIZE); + stack_args_p += WORD_SIZE; + } + + if (ecif->avalue == NULL) { + return; /* no arguments to prepare */ + } + + for (i = 0, p_arg = ecif->cif->arg_types; i < ecif->cif->nargs; + i++, p_arg++) + { + size_t size = (*p_arg)->size; + int type = (*p_arg)->type; + void* value = p_argv[i]; + char* addr = stack_args_p; + int aligned_size = WORD_ALIGN(size); + + /* force word alignment on the stack */ + stack_args_p += aligned_size; + + switch (type) + { + case FFI_TYPE_UINT8: + *(unsigned int *)addr = (unsigned int)*(UINT8*)(value); + break; + case FFI_TYPE_SINT8: + *(signed int *)addr = (signed int)*(SINT8*)(value); + break; + case FFI_TYPE_UINT16: + *(unsigned int *)addr = (unsigned int)*(UINT16*)(value); + break; + case FFI_TYPE_SINT16: + *(signed int *)addr = (signed int)*(SINT16*)(value); + break; + case FFI_TYPE_STRUCT: +#if __BIG_ENDIAN__ + /* + * MicroBlaze toolchain appears to emit: + * bsrli r5, r5, 8 (caller) + * ... + * <branch to callee> + * ... + * bslli r5, r5, 8 (callee) + * + * For structs like "struct a { uint8_t a[3]; };", when passed + * by value. + * + * Structs like "struct b { uint16_t a; };" are also expected + * to be packed strangely in registers. + * + * This appears to be because the microblaze toolchain expects + * "struct b == uint16_t", which is only any issue for big + * endian. + * + * The following is a work around for big-endian only, for the + * above mentioned case, it will re-align the contents of a + * <= 3-byte struct value. + */ + if (size < WORD_SIZE) + { + memcpy (addr + (WORD_SIZE - size), value, size); + break; + } +#endif + case FFI_TYPE_SINT32: + case FFI_TYPE_UINT32: + case FFI_TYPE_FLOAT: + case FFI_TYPE_SINT64: + case FFI_TYPE_UINT64: + case FFI_TYPE_DOUBLE: + default: + memcpy(addr, value, aligned_size); + } + } +} + +ffi_status ffi_prep_cif_machdep(ffi_cif* cif) +{ + /* check ABI */ + switch (cif->abi) + { + case FFI_SYSV: + break; + default: + return FFI_BAD_ABI; + } + return FFI_OK; +} + +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_SYSV: + ffi_call_SYSV(ffi_prep_args, &ecif, cif->bytes, cif->flags, + ecif.rvalue, fn, cif->rtype->type, cif->rtype->size); + break; + default: + FFI_ASSERT(0); + break; + } +} + +void ffi_closure_call_SYSV(void* register_args, void* stack_args, + ffi_closure* closure, void* rvalue, + unsigned int* rtype, unsigned int* rsize) +{ + /* prepare arguments for closure call */ + ffi_cif* cif = closure->cif; + ffi_type** arg_types = cif->arg_types; + + /* re-allocate data for the args. This needs to be done in order to keep + * multi-word objects (e.g. structs) in contiguous memory. Callers are not + * required to store the value of args in the lower 6 words in the stack + * (although they are allocated in the stack). + */ + char* stackclone = alloca(cif->bytes); + void** avalue = alloca(cif->nargs * sizeof(void*)); + void* struct_rvalue = NULL; + char* ptr = stackclone; + int i; + + /* copy registers into stack clone */ + int registers_used = cif->bytes; + if (registers_used > ARGS_REGISTER_SIZE) { + registers_used = ARGS_REGISTER_SIZE; + } + memcpy(stackclone, register_args, registers_used); + + /* copy stack allocated args into stack clone */ + if (cif->bytes > ARGS_REGISTER_SIZE) { + int stack_used = cif->bytes - ARGS_REGISTER_SIZE; + memcpy(stackclone + ARGS_REGISTER_SIZE, stack_args, stack_used); + } + + /* preserve struct type return pointer passing */ + if ((cif->rtype != NULL) && (cif->rtype->type == FFI_TYPE_STRUCT)) { + struct_rvalue = *((void**)ptr); + ptr += WORD_SIZE; + } + + /* populate arg pointer list */ + for (i = 0; i < cif->nargs; i++) + { + switch (arg_types[i]->type) + { + case FFI_TYPE_SINT8: + case FFI_TYPE_UINT8: +#ifdef __BIG_ENDIAN__ + avalue[i] = ptr + 3; +#else + avalue[i] = ptr; +#endif + break; + case FFI_TYPE_SINT16: + case FFI_TYPE_UINT16: +#ifdef __BIG_ENDIAN__ + avalue[i] = ptr + 2; +#else + avalue[i] = ptr; +#endif + break; + case FFI_TYPE_STRUCT: +#if __BIG_ENDIAN__ + /* + * Work around strange ABI behaviour. + * (see info in ffi_prep_args) + */ + if (arg_types[i]->size < WORD_SIZE) + { + memcpy (ptr, ptr + (WORD_SIZE - arg_types[i]->size), arg_types[i]->size); + } +#endif + avalue[i] = (void*)ptr; + break; + case FFI_TYPE_UINT64: + case FFI_TYPE_SINT64: + case FFI_TYPE_DOUBLE: + avalue[i] = ptr; + break; + case FFI_TYPE_SINT32: + case FFI_TYPE_UINT32: + case FFI_TYPE_FLOAT: + default: + /* default 4-byte argument */ + avalue[i] = ptr; + break; + } + ptr += WORD_ALIGN(arg_types[i]->size); + } + + /* set the return type info passed back to the wrapper */ + *rsize = cif->rtype->size; + *rtype = cif->rtype->type; + if (struct_rvalue != NULL) { + closure->fun(cif, struct_rvalue, avalue, closure->user_data); + /* copy struct return pointer value into function return value */ + *((void**)rvalue) = struct_rvalue; + } else { + closure->fun(cif, rvalue, avalue, closure->user_data); + } +} + +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 long* tramp = (unsigned long*)&(closure->tramp[0]); + unsigned long cls = (unsigned long)codeloc; + unsigned long fn = 0; + unsigned long fn_closure_call_sysv = (unsigned long)ffi_closure_call_SYSV; + + closure->cif = cif; + closure->fun = fun; + closure->user_data = user_data; + + switch (cif->abi) + { + case FFI_SYSV: + fn = (unsigned long)ffi_closure_SYSV; + + /* load r11 (temp) with fn */ + /* imm fn(upper) */ + tramp[0] = 0xb0000000 | ((fn >> 16) & 0xffff); + /* addik r11, r0, fn(lower) */ + tramp[1] = 0x31600000 | (fn & 0xffff); + + /* load r12 (temp) with cls */ + /* imm cls(upper) */ + tramp[2] = 0xb0000000 | ((cls >> 16) & 0xffff); + /* addik r12, r0, cls(lower) */ + tramp[3] = 0x31800000 | (cls & 0xffff); + + /* load r3 (temp) with ffi_closure_call_SYSV */ + /* imm fn_closure_call_sysv(upper) */ + tramp[4] = 0xb0000000 | ((fn_closure_call_sysv >> 16) & 0xffff); + /* addik r3, r0, fn_closure_call_sysv(lower) */ + tramp[5] = 0x30600000 | (fn_closure_call_sysv & 0xffff); + /* branch/jump to address stored in r11 (fn) */ + tramp[6] = 0x98085800; /* bra r11 */ + + break; + default: + return FFI_BAD_ABI; + } + return FFI_OK; +} |