/Modules/_ctypes/libffi/src/ia64/ffi.c
http://unladen-swallow.googlecode.com/ · C · 580 lines · 413 code · 84 blank · 83 comment · 72 complexity · 7ca86e7025e65dd69d1ed227e9fe964e MD5 · raw file
- /* -----------------------------------------------------------------------
- ffi.c - Copyright (c) 1998, 2007, 2008 Red Hat, Inc.
- Copyright (c) 2000 Hewlett Packard Company
-
- IA64 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>
- #include <stdbool.h>
- #include <float.h>
- #include "ia64_flags.h"
- /* A 64-bit pointer value. In LP64 mode, this is effectively a plain
- pointer. In ILP32 mode, it's a pointer that's been extended to
- 64 bits by "addp4". */
- typedef void *PTR64 __attribute__((mode(DI)));
- /* Memory image of fp register contents. This is the implementation
- specific format used by ldf.fill/stf.spill. All we care about is
- that it wants a 16 byte aligned slot. */
- typedef struct
- {
- UINT64 x[2] __attribute__((aligned(16)));
- } fpreg;
- /* The stack layout given to ffi_call_unix and ffi_closure_unix_inner. */
- struct ia64_args
- {
- fpreg fp_regs[8]; /* Contents of 8 fp arg registers. */
- UINT64 gp_regs[8]; /* Contents of 8 gp arg registers. */
- UINT64 other_args[]; /* Arguments passed on stack, variable size. */
- };
- /* Adjust ADDR, a pointer to an 8 byte slot, to point to the low LEN bytes. */
- static inline void *
- endian_adjust (void *addr, size_t len)
- {
- #ifdef __BIG_ENDIAN__
- return addr + (8 - len);
- #else
- return addr;
- #endif
- }
- /* Store VALUE to ADDR in the current cpu implementation's fp spill format.
- This is a macro instead of a function, so that it works for all 3 floating
- point types without type conversions. Type conversion to long double breaks
- the denorm support. */
- #define stf_spill(addr, value) \
- asm ("stf.spill %0 = %1%P0" : "=m" (*addr) : "f"(value));
- /* Load a value from ADDR, which is in the current cpu implementation's
- fp spill format. As above, this must also be a macro. */
- #define ldf_fill(result, addr) \
- asm ("ldf.fill %0 = %1%P1" : "=f"(result) : "m"(*addr));
- /* Return the size of the C type associated with with TYPE. Which will
- be one of the FFI_IA64_TYPE_HFA_* values. */
- static size_t
- hfa_type_size (int type)
- {
- switch (type)
- {
- case FFI_IA64_TYPE_HFA_FLOAT:
- return sizeof(float);
- case FFI_IA64_TYPE_HFA_DOUBLE:
- return sizeof(double);
- case FFI_IA64_TYPE_HFA_LDOUBLE:
- return sizeof(__float80);
- default:
- abort ();
- }
- }
- /* Load from ADDR a value indicated by TYPE. Which will be one of
- the FFI_IA64_TYPE_HFA_* values. */
- static void
- hfa_type_load (fpreg *fpaddr, int type, void *addr)
- {
- switch (type)
- {
- case FFI_IA64_TYPE_HFA_FLOAT:
- stf_spill (fpaddr, *(float *) addr);
- return;
- case FFI_IA64_TYPE_HFA_DOUBLE:
- stf_spill (fpaddr, *(double *) addr);
- return;
- case FFI_IA64_TYPE_HFA_LDOUBLE:
- stf_spill (fpaddr, *(__float80 *) addr);
- return;
- default:
- abort ();
- }
- }
- /* Load VALUE into ADDR as indicated by TYPE. Which will be one of
- the FFI_IA64_TYPE_HFA_* values. */
- static void
- hfa_type_store (int type, void *addr, fpreg *fpaddr)
- {
- switch (type)
- {
- case FFI_IA64_TYPE_HFA_FLOAT:
- {
- float result;
- ldf_fill (result, fpaddr);
- *(float *) addr = result;
- break;
- }
- case FFI_IA64_TYPE_HFA_DOUBLE:
- {
- double result;
- ldf_fill (result, fpaddr);
- *(double *) addr = result;
- break;
- }
- case FFI_IA64_TYPE_HFA_LDOUBLE:
- {
- __float80 result;
- ldf_fill (result, fpaddr);
- *(__float80 *) addr = result;
- break;
- }
- default:
- abort ();
- }
- }
- /* Is TYPE a struct containing floats, doubles, or extended doubles,
- all of the same fp type? If so, return the element type. Return
- FFI_TYPE_VOID if not. */
- static int
- hfa_element_type (ffi_type *type, int nested)
- {
- int element = FFI_TYPE_VOID;
- switch (type->type)
- {
- case FFI_TYPE_FLOAT:
- /* We want to return VOID for raw floating-point types, but the
- synthetic HFA type if we're nested within an aggregate. */
- if (nested)
- element = FFI_IA64_TYPE_HFA_FLOAT;
- break;
- case FFI_TYPE_DOUBLE:
- /* Similarly. */
- if (nested)
- element = FFI_IA64_TYPE_HFA_DOUBLE;
- break;
- case FFI_TYPE_LONGDOUBLE:
- /* Similarly, except that that HFA is true for double extended,
- but not quad precision. Both have sizeof == 16, so tell the
- difference based on the precision. */
- if (LDBL_MANT_DIG == 64 && nested)
- element = FFI_IA64_TYPE_HFA_LDOUBLE;
- break;
- case FFI_TYPE_STRUCT:
- {
- ffi_type **ptr = &type->elements[0];
- for (ptr = &type->elements[0]; *ptr ; ptr++)
- {
- int sub_element = hfa_element_type (*ptr, 1);
- if (sub_element == FFI_TYPE_VOID)
- return FFI_TYPE_VOID;
- if (element == FFI_TYPE_VOID)
- element = sub_element;
- else if (element != sub_element)
- return FFI_TYPE_VOID;
- }
- }
- break;
- default:
- return FFI_TYPE_VOID;
- }
- return element;
- }
- /* Perform machine dependent cif processing. */
- ffi_status
- ffi_prep_cif_machdep(ffi_cif *cif)
- {
- int flags;
- /* Adjust cif->bytes to include space for the bits of the ia64_args frame
- that preceeds the integer register portion. The estimate that the
- generic bits did for the argument space required is good enough for the
- integer component. */
- cif->bytes += offsetof(struct ia64_args, gp_regs[0]);
- if (cif->bytes < sizeof(struct ia64_args))
- cif->bytes = sizeof(struct ia64_args);
- /* Set the return type flag. */
- flags = cif->rtype->type;
- switch (cif->rtype->type)
- {
- case FFI_TYPE_LONGDOUBLE:
- /* Leave FFI_TYPE_LONGDOUBLE as meaning double extended precision,
- and encode quad precision as a two-word integer structure. */
- if (LDBL_MANT_DIG != 64)
- flags = FFI_IA64_TYPE_SMALL_STRUCT | (16 << 8);
- break;
- case FFI_TYPE_STRUCT:
- {
- size_t size = cif->rtype->size;
- int hfa_type = hfa_element_type (cif->rtype, 0);
- if (hfa_type != FFI_TYPE_VOID)
- {
- size_t nelts = size / hfa_type_size (hfa_type);
- if (nelts <= 8)
- flags = hfa_type | (size << 8);
- }
- else
- {
- if (size <= 32)
- flags = FFI_IA64_TYPE_SMALL_STRUCT | (size << 8);
- }
- }
- break;
- default:
- break;
- }
- cif->flags = flags;
- return FFI_OK;
- }
- extern int ffi_call_unix (struct ia64_args *, PTR64, void (*)(void), UINT64);
- void
- ffi_call(ffi_cif *cif, void (*fn)(void), void *rvalue, void **avalue)
- {
- struct ia64_args *stack;
- long i, avn, gpcount, fpcount;
- ffi_type **p_arg;
- FFI_ASSERT (cif->abi == FFI_UNIX);
- /* If we have no spot for a return value, make one. */
- if (rvalue == NULL && cif->rtype->type != FFI_TYPE_VOID)
- rvalue = alloca (cif->rtype->size);
-
- /* Allocate the stack frame. */
- stack = alloca (cif->bytes);
- gpcount = fpcount = 0;
- avn = cif->nargs;
- for (i = 0, p_arg = cif->arg_types; i < avn; i++, p_arg++)
- {
- switch ((*p_arg)->type)
- {
- case FFI_TYPE_SINT8:
- stack->gp_regs[gpcount++] = *(SINT8 *)avalue[i];
- break;
- case FFI_TYPE_UINT8:
- stack->gp_regs[gpcount++] = *(UINT8 *)avalue[i];
- break;
- case FFI_TYPE_SINT16:
- stack->gp_regs[gpcount++] = *(SINT16 *)avalue[i];
- break;
- case FFI_TYPE_UINT16:
- stack->gp_regs[gpcount++] = *(UINT16 *)avalue[i];
- break;
- case FFI_TYPE_SINT32:
- stack->gp_regs[gpcount++] = *(SINT32 *)avalue[i];
- break;
- case FFI_TYPE_UINT32:
- stack->gp_regs[gpcount++] = *(UINT32 *)avalue[i];
- break;
- case FFI_TYPE_SINT64:
- case FFI_TYPE_UINT64:
- stack->gp_regs[gpcount++] = *(UINT64 *)avalue[i];
- break;
- case FFI_TYPE_POINTER:
- stack->gp_regs[gpcount++] = (UINT64)(PTR64) *(void **)avalue[i];
- break;
- case FFI_TYPE_FLOAT:
- if (gpcount < 8 && fpcount < 8)
- stf_spill (&stack->fp_regs[fpcount++], *(float *)avalue[i]);
- stack->gp_regs[gpcount++] = *(UINT32 *)avalue[i];
- break;
- case FFI_TYPE_DOUBLE:
- if (gpcount < 8 && fpcount < 8)
- stf_spill (&stack->fp_regs[fpcount++], *(double *)avalue[i]);
- stack->gp_regs[gpcount++] = *(UINT64 *)avalue[i];
- break;
- case FFI_TYPE_LONGDOUBLE:
- if (gpcount & 1)
- gpcount++;
- if (LDBL_MANT_DIG == 64 && gpcount < 8 && fpcount < 8)
- stf_spill (&stack->fp_regs[fpcount++], *(__float80 *)avalue[i]);
- memcpy (&stack->gp_regs[gpcount], avalue[i], 16);
- gpcount += 2;
- break;
- case FFI_TYPE_STRUCT:
- {
- size_t size = (*p_arg)->size;
- size_t align = (*p_arg)->alignment;
- int hfa_type = hfa_element_type (*p_arg, 0);
- FFI_ASSERT (align <= 16);
- if (align == 16 && (gpcount & 1))
- gpcount++;
- if (hfa_type != FFI_TYPE_VOID)
- {
- size_t hfa_size = hfa_type_size (hfa_type);
- size_t offset = 0;
- size_t gp_offset = gpcount * 8;
- while (fpcount < 8
- && offset < size
- && gp_offset < 8 * 8)
- {
- hfa_type_load (&stack->fp_regs[fpcount], hfa_type,
- avalue[i] + offset);
- offset += hfa_size;
- gp_offset += hfa_size;
- fpcount += 1;
- }
- }
- memcpy (&stack->gp_regs[gpcount], avalue[i], size);
- gpcount += (size + 7) / 8;
- }
- break;
- default:
- abort ();
- }
- }
- ffi_call_unix (stack, rvalue, fn, cif->flags);
- }
- /* Closures represent a pair consisting of a function pointer, and
- some user data. A closure is invoked by reinterpreting the closure
- as a function pointer, and branching to it. Thus we can make an
- interpreted function callable as a C function: We turn the
- interpreter itself, together with a pointer specifying the
- interpreted procedure, into a closure.
- For IA64, function pointer are already pairs consisting of a code
- pointer, and a gp pointer. The latter is needed to access global
- variables. Here we set up such a pair as the first two words of
- the closure (in the "trampoline" area), but we replace the gp
- pointer with a pointer to the closure itself. We also add the real
- gp pointer to the closure. This allows the function entry code to
- both retrieve the user data, and to restire the correct gp pointer. */
- extern void ffi_closure_unix ();
- ffi_status
- ffi_prep_closure_loc (ffi_closure* closure,
- ffi_cif* cif,
- void (*fun)(ffi_cif*,void*,void**,void*),
- void *user_data,
- void *codeloc)
- {
- /* The layout of a function descriptor. A C function pointer really
- points to one of these. */
- struct ia64_fd
- {
- UINT64 code_pointer;
- UINT64 gp;
- };
- struct ffi_ia64_trampoline_struct
- {
- UINT64 code_pointer; /* Pointer to ffi_closure_unix. */
- UINT64 fake_gp; /* Pointer to closure, installed as gp. */
- UINT64 real_gp; /* Real gp value. */
- };
- struct ffi_ia64_trampoline_struct *tramp;
- struct ia64_fd *fd;
- FFI_ASSERT (cif->abi == FFI_UNIX);
- tramp = (struct ffi_ia64_trampoline_struct *)closure->tramp;
- fd = (struct ia64_fd *)(void *)ffi_closure_unix;
- tramp->code_pointer = fd->code_pointer;
- tramp->real_gp = fd->gp;
- tramp->fake_gp = (UINT64)(PTR64)codeloc;
- closure->cif = cif;
- closure->user_data = user_data;
- closure->fun = fun;
- return FFI_OK;
- }
- UINT64
- ffi_closure_unix_inner (ffi_closure *closure, struct ia64_args *stack,
- void *rvalue, void *r8)
- {
- ffi_cif *cif;
- void **avalue;
- ffi_type **p_arg;
- long i, avn, gpcount, fpcount;
- cif = closure->cif;
- avn = cif->nargs;
- avalue = alloca (avn * sizeof (void *));
- /* If the structure return value is passed in memory get that location
- from r8 so as to pass the value directly back to the caller. */
- if (cif->flags == FFI_TYPE_STRUCT)
- rvalue = r8;
- gpcount = fpcount = 0;
- for (i = 0, p_arg = cif->arg_types; i < avn; i++, p_arg++)
- {
- switch ((*p_arg)->type)
- {
- case FFI_TYPE_SINT8:
- case FFI_TYPE_UINT8:
- avalue[i] = endian_adjust(&stack->gp_regs[gpcount++], 1);
- break;
- case FFI_TYPE_SINT16:
- case FFI_TYPE_UINT16:
- avalue[i] = endian_adjust(&stack->gp_regs[gpcount++], 2);
- break;
- case FFI_TYPE_SINT32:
- case FFI_TYPE_UINT32:
- avalue[i] = endian_adjust(&stack->gp_regs[gpcount++], 4);
- break;
- case FFI_TYPE_SINT64:
- case FFI_TYPE_UINT64:
- avalue[i] = &stack->gp_regs[gpcount++];
- break;
- case FFI_TYPE_POINTER:
- avalue[i] = endian_adjust(&stack->gp_regs[gpcount++], sizeof(void*));
- break;
- case FFI_TYPE_FLOAT:
- if (gpcount < 8 && fpcount < 8)
- {
- fpreg *addr = &stack->fp_regs[fpcount++];
- float result;
- avalue[i] = addr;
- ldf_fill (result, addr);
- *(float *)addr = result;
- }
- else
- avalue[i] = endian_adjust(&stack->gp_regs[gpcount], 4);
- gpcount++;
- break;
- case FFI_TYPE_DOUBLE:
- if (gpcount < 8 && fpcount < 8)
- {
- fpreg *addr = &stack->fp_regs[fpcount++];
- double result;
- avalue[i] = addr;
- ldf_fill (result, addr);
- *(double *)addr = result;
- }
- else
- avalue[i] = &stack->gp_regs[gpcount];
- gpcount++;
- break;
- case FFI_TYPE_LONGDOUBLE:
- if (gpcount & 1)
- gpcount++;
- if (LDBL_MANT_DIG == 64 && gpcount < 8 && fpcount < 8)
- {
- fpreg *addr = &stack->fp_regs[fpcount++];
- __float80 result;
- avalue[i] = addr;
- ldf_fill (result, addr);
- *(__float80 *)addr = result;
- }
- else
- avalue[i] = &stack->gp_regs[gpcount];
- gpcount += 2;
- break;
- case FFI_TYPE_STRUCT:
- {
- size_t size = (*p_arg)->size;
- size_t align = (*p_arg)->alignment;
- int hfa_type = hfa_element_type (*p_arg, 0);
- FFI_ASSERT (align <= 16);
- if (align == 16 && (gpcount & 1))
- gpcount++;
- if (hfa_type != FFI_TYPE_VOID)
- {
- size_t hfa_size = hfa_type_size (hfa_type);
- size_t offset = 0;
- size_t gp_offset = gpcount * 8;
- void *addr = alloca (size);
- avalue[i] = addr;
- while (fpcount < 8
- && offset < size
- && gp_offset < 8 * 8)
- {
- hfa_type_store (hfa_type, addr + offset,
- &stack->fp_regs[fpcount]);
- offset += hfa_size;
- gp_offset += hfa_size;
- fpcount += 1;
- }
- if (offset < size)
- memcpy (addr + offset, (char *)stack->gp_regs + gp_offset,
- size - offset);
- }
- else
- avalue[i] = &stack->gp_regs[gpcount];
- gpcount += (size + 7) / 8;
- }
- break;
- default:
- abort ();
- }
- }
- closure->fun (cif, rvalue, avalue, closure->user_data);
- return cif->flags;
- }