summaryrefslogtreecommitdiff
path: root/src/aarch64/ffi.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/aarch64/ffi.c')
-rw-r--r--src/aarch64/ffi.c1076
1 files changed, 1076 insertions, 0 deletions
diff --git a/src/aarch64/ffi.c b/src/aarch64/ffi.c
new file mode 100644
index 0000000..1405665
--- /dev/null
+++ b/src/aarch64/ffi.c
@@ -0,0 +1,1076 @@
+/* Copyright (c) 2009, 2010, 2011, 2012 ARM Ltd.
+
+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 <stdio.h>
+
+#include <ffi.h>
+#include <ffi_common.h>
+
+#include <stdlib.h>
+
+/* Stack alignment requirement in bytes */
+#define AARCH64_STACK_ALIGN 16
+
+#define N_X_ARG_REG 8
+#define N_V_ARG_REG 8
+
+#define AARCH64_FFI_WITH_V (1 << AARCH64_FFI_WITH_V_BIT)
+
+union _d
+{
+ UINT64 d;
+ UINT32 s[2];
+};
+
+struct call_context
+{
+ UINT64 x [AARCH64_N_XREG];
+ struct
+ {
+ union _d d[2];
+ } v [AARCH64_N_VREG];
+};
+
+static void *
+get_x_addr (struct call_context *context, unsigned n)
+{
+ return &context->x[n];
+}
+
+static void *
+get_s_addr (struct call_context *context, unsigned n)
+{
+#if defined __AARCH64EB__
+ return &context->v[n].d[1].s[1];
+#else
+ return &context->v[n].d[0].s[0];
+#endif
+}
+
+static void *
+get_d_addr (struct call_context *context, unsigned n)
+{
+#if defined __AARCH64EB__
+ return &context->v[n].d[1];
+#else
+ return &context->v[n].d[0];
+#endif
+}
+
+static void *
+get_v_addr (struct call_context *context, unsigned n)
+{
+ return &context->v[n];
+}
+
+/* Return the memory location at which a basic type would reside
+ were it to have been stored in register n. */
+
+static void *
+get_basic_type_addr (unsigned short type, struct call_context *context,
+ unsigned n)
+{
+ switch (type)
+ {
+ case FFI_TYPE_FLOAT:
+ return get_s_addr (context, n);
+ case FFI_TYPE_DOUBLE:
+ return get_d_addr (context, n);
+ case FFI_TYPE_LONGDOUBLE:
+ return get_v_addr (context, n);
+ case FFI_TYPE_UINT8:
+ case FFI_TYPE_SINT8:
+ case FFI_TYPE_UINT16:
+ case FFI_TYPE_SINT16:
+ case FFI_TYPE_UINT32:
+ case FFI_TYPE_SINT32:
+ case FFI_TYPE_INT:
+ case FFI_TYPE_POINTER:
+ case FFI_TYPE_UINT64:
+ case FFI_TYPE_SINT64:
+ return get_x_addr (context, n);
+ default:
+ FFI_ASSERT (0);
+ return NULL;
+ }
+}
+
+/* Return the alignment width for each of the basic types. */
+
+static size_t
+get_basic_type_alignment (unsigned short type)
+{
+ switch (type)
+ {
+ case FFI_TYPE_FLOAT:
+ case FFI_TYPE_DOUBLE:
+ return sizeof (UINT64);
+ case FFI_TYPE_LONGDOUBLE:
+ return sizeof (long double);
+ case FFI_TYPE_UINT8:
+ case FFI_TYPE_SINT8:
+ case FFI_TYPE_UINT16:
+ case FFI_TYPE_SINT16:
+ case FFI_TYPE_UINT32:
+ case FFI_TYPE_INT:
+ case FFI_TYPE_SINT32:
+ case FFI_TYPE_POINTER:
+ case FFI_TYPE_UINT64:
+ case FFI_TYPE_SINT64:
+ return sizeof (UINT64);
+
+ default:
+ FFI_ASSERT (0);
+ return 0;
+ }
+}
+
+/* Return the size in bytes for each of the basic types. */
+
+static size_t
+get_basic_type_size (unsigned short type)
+{
+ switch (type)
+ {
+ case FFI_TYPE_FLOAT:
+ return sizeof (UINT32);
+ case FFI_TYPE_DOUBLE:
+ return sizeof (UINT64);
+ case FFI_TYPE_LONGDOUBLE:
+ return sizeof (long double);
+ case FFI_TYPE_UINT8:
+ return sizeof (UINT8);
+ case FFI_TYPE_SINT8:
+ return sizeof (SINT8);
+ case FFI_TYPE_UINT16:
+ return sizeof (UINT16);
+ case FFI_TYPE_SINT16:
+ return sizeof (SINT16);
+ case FFI_TYPE_UINT32:
+ return sizeof (UINT32);
+ case FFI_TYPE_INT:
+ case FFI_TYPE_SINT32:
+ return sizeof (SINT32);
+ case FFI_TYPE_POINTER:
+ case FFI_TYPE_UINT64:
+ return sizeof (UINT64);
+ case FFI_TYPE_SINT64:
+ return sizeof (SINT64);
+
+ default:
+ FFI_ASSERT (0);
+ return 0;
+ }
+}
+
+extern void
+ffi_call_SYSV (unsigned (*)(struct call_context *context, unsigned char *,
+ extended_cif *),
+ struct call_context *context,
+ extended_cif *,
+ unsigned,
+ void (*fn)(void));
+
+extern void
+ffi_closure_SYSV (ffi_closure *);
+
+/* Test for an FFI floating point representation. */
+
+static unsigned
+is_floating_type (unsigned short type)
+{
+ return (type == FFI_TYPE_FLOAT || type == FFI_TYPE_DOUBLE
+ || type == FFI_TYPE_LONGDOUBLE);
+}
+
+/* Test for a homogeneous structure. */
+
+static unsigned short
+get_homogeneous_type (ffi_type *ty)
+{
+ if (ty->type == FFI_TYPE_STRUCT && ty->elements)
+ {
+ unsigned i;
+ unsigned short candidate_type
+ = get_homogeneous_type (ty->elements[0]);
+ for (i =1; ty->elements[i]; i++)
+ {
+ unsigned short iteration_type = 0;
+ /* If we have a nested struct, we must find its homogeneous type.
+ If that fits with our candidate type, we are still
+ homogeneous. */
+ if (ty->elements[i]->type == FFI_TYPE_STRUCT
+ && ty->elements[i]->elements)
+ {
+ iteration_type = get_homogeneous_type (ty->elements[i]);
+ }
+ else
+ {
+ iteration_type = ty->elements[i]->type;
+ }
+
+ /* If we are not homogeneous, return FFI_TYPE_STRUCT. */
+ if (candidate_type != iteration_type)
+ return FFI_TYPE_STRUCT;
+ }
+ return candidate_type;
+ }
+
+ /* Base case, we have no more levels of nesting, so we
+ are a basic type, and so, trivially homogeneous in that type. */
+ return ty->type;
+}
+
+/* Determine the number of elements within a STRUCT.
+
+ Note, we must handle nested structs.
+
+ If ty is not a STRUCT this function will return 0. */
+
+static unsigned
+element_count (ffi_type *ty)
+{
+ if (ty->type == FFI_TYPE_STRUCT && ty->elements)
+ {
+ unsigned n;
+ unsigned elems = 0;
+ for (n = 0; ty->elements[n]; n++)
+ {
+ if (ty->elements[n]->type == FFI_TYPE_STRUCT
+ && ty->elements[n]->elements)
+ elems += element_count (ty->elements[n]);
+ else
+ elems++;
+ }
+ return elems;
+ }
+ return 0;
+}
+
+/* Test for a homogeneous floating point aggregate.
+
+ A homogeneous floating point aggregate is a homogeneous aggregate of
+ a half- single- or double- precision floating point type with one
+ to four elements. Note that this includes nested structs of the
+ basic type. */
+
+static int
+is_hfa (ffi_type *ty)
+{
+ if (ty->type == FFI_TYPE_STRUCT
+ && ty->elements[0]
+ && is_floating_type (get_homogeneous_type (ty)))
+ {
+ unsigned n = element_count (ty);
+ return n >= 1 && n <= 4;
+ }
+ return 0;
+}
+
+/* Test if an ffi_type is a candidate for passing in a register.
+
+ This test does not check that sufficient registers of the
+ appropriate class are actually available, merely that IFF
+ sufficient registers are available then the argument will be passed
+ in register(s).
+
+ Note that an ffi_type that is deemed to be a register candidate
+ will always be returned in registers.
+
+ Returns 1 if a register candidate else 0. */
+
+static int
+is_register_candidate (ffi_type *ty)
+{
+ switch (ty->type)
+ {
+ case FFI_TYPE_VOID:
+ case FFI_TYPE_FLOAT:
+ case FFI_TYPE_DOUBLE:
+ case FFI_TYPE_LONGDOUBLE:
+ case FFI_TYPE_UINT8:
+ case FFI_TYPE_UINT16:
+ case FFI_TYPE_UINT32:
+ case FFI_TYPE_UINT64:
+ case FFI_TYPE_POINTER:
+ case FFI_TYPE_SINT8:
+ case FFI_TYPE_SINT16:
+ case FFI_TYPE_SINT32:
+ case FFI_TYPE_INT:
+ case FFI_TYPE_SINT64:
+ return 1;
+
+ case FFI_TYPE_STRUCT:
+ if (is_hfa (ty))
+ {
+ return 1;
+ }
+ else if (ty->size > 16)
+ {
+ /* Too large. Will be replaced with a pointer to memory. The
+ pointer MAY be passed in a register, but the value will
+ not. This test specifically fails since the argument will
+ never be passed by value in registers. */
+ return 0;
+ }
+ else
+ {
+ /* Might be passed in registers depending on the number of
+ registers required. */
+ return (ty->size + 7) / 8 < N_X_ARG_REG;
+ }
+ break;
+
+ default:
+ FFI_ASSERT (0);
+ break;
+ }
+
+ return 0;
+}
+
+/* Test if an ffi_type argument or result is a candidate for a vector
+ register. */
+
+static int
+is_v_register_candidate (ffi_type *ty)
+{
+ return is_floating_type (ty->type)
+ || (ty->type == FFI_TYPE_STRUCT && is_hfa (ty));
+}
+
+/* Representation of the procedure call argument marshalling
+ state.
+
+ The terse state variable names match the names used in the AARCH64
+ PCS. */
+
+struct arg_state
+{
+ unsigned ngrn; /* Next general-purpose register number. */
+ unsigned nsrn; /* Next vector register number. */
+ unsigned nsaa; /* Next stack offset. */
+};
+
+/* Initialize a procedure call argument marshalling state. */
+static void
+arg_init (struct arg_state *state, unsigned call_frame_size)
+{
+ state->ngrn = 0;
+ state->nsrn = 0;
+ state->nsaa = 0;
+}
+
+/* Return the number of available consecutive core argument
+ registers. */
+
+static unsigned
+available_x (struct arg_state *state)
+{
+ return N_X_ARG_REG - state->ngrn;
+}
+
+/* Return the number of available consecutive vector argument
+ registers. */
+
+static unsigned
+available_v (struct arg_state *state)
+{
+ return N_V_ARG_REG - state->nsrn;
+}
+
+static void *
+allocate_to_x (struct call_context *context, struct arg_state *state)
+{
+ FFI_ASSERT (state->ngrn < N_X_ARG_REG)
+ return get_x_addr (context, (state->ngrn)++);
+}
+
+static void *
+allocate_to_s (struct call_context *context, struct arg_state *state)
+{
+ FFI_ASSERT (state->nsrn < N_V_ARG_REG)
+ return get_s_addr (context, (state->nsrn)++);
+}
+
+static void *
+allocate_to_d (struct call_context *context, struct arg_state *state)
+{
+ FFI_ASSERT (state->nsrn < N_V_ARG_REG)
+ return get_d_addr (context, (state->nsrn)++);
+}
+
+static void *
+allocate_to_v (struct call_context *context, struct arg_state *state)
+{
+ FFI_ASSERT (state->nsrn < N_V_ARG_REG)
+ return get_v_addr (context, (state->nsrn)++);
+}
+
+/* Allocate an aligned slot on the stack and return a pointer to it. */
+static void *
+allocate_to_stack (struct arg_state *state, void *stack, unsigned alignment,
+ unsigned size)
+{
+ void *allocation;
+
+ /* Round up the NSAA to the larger of 8 or the natural
+ alignment of the argument's type. */
+ state->nsaa = ALIGN (state->nsaa, alignment);
+ state->nsaa = ALIGN (state->nsaa, alignment);
+ state->nsaa = ALIGN (state->nsaa, 8);
+
+ allocation = stack + state->nsaa;
+
+ state->nsaa += size;
+ return allocation;
+}
+
+static void
+copy_basic_type (void *dest, void *source, unsigned short type)
+{
+ /* This is neccessary to ensure that basic types are copied
+ sign extended to 64-bits as libffi expects. */
+ switch (type)
+ {
+ case FFI_TYPE_FLOAT:
+ *(float *) dest = *(float *) source;
+ break;
+ case FFI_TYPE_DOUBLE:
+ *(double *) dest = *(double *) source;
+ break;
+ case FFI_TYPE_LONGDOUBLE:
+ *(long double *) dest = *(long double *) source;
+ break;
+ case FFI_TYPE_UINT8:
+ *(ffi_arg *) dest = *(UINT8 *) source;
+ break;
+ case FFI_TYPE_SINT8:
+ *(ffi_sarg *) dest = *(SINT8 *) source;
+ break;
+ case FFI_TYPE_UINT16:
+ *(ffi_arg *) dest = *(UINT16 *) source;
+ break;
+ case FFI_TYPE_SINT16:
+ *(ffi_sarg *) dest = *(SINT16 *) source;
+ break;
+ case FFI_TYPE_UINT32:
+ *(ffi_arg *) dest = *(UINT32 *) source;
+ break;
+ case FFI_TYPE_INT:
+ case FFI_TYPE_SINT32:
+ *(ffi_sarg *) dest = *(SINT32 *) source;
+ break;
+ case FFI_TYPE_POINTER:
+ case FFI_TYPE_UINT64:
+ *(ffi_arg *) dest = *(UINT64 *) source;
+ break;
+ case FFI_TYPE_SINT64:
+ *(ffi_sarg *) dest = *(SINT64 *) source;
+ break;
+
+ default:
+ FFI_ASSERT (0);
+ }
+}
+
+static void
+copy_hfa_to_reg_or_stack (void *memory,
+ ffi_type *ty,
+ struct call_context *context,
+ unsigned char *stack,
+ struct arg_state *state)
+{
+ unsigned elems = element_count (ty);
+ if (available_v (state) < elems)
+ {
+ /* There are insufficient V registers. Further V register allocations
+ are prevented, the NSAA is adjusted (by allocate_to_stack ())
+ and the argument is copied to memory at the adjusted NSAA. */
+ state->nsrn = N_V_ARG_REG;
+ memcpy (allocate_to_stack (state, stack, ty->alignment, ty->size),
+ memory,
+ ty->size);
+ }
+ else
+ {
+ int i;
+ unsigned short type = get_homogeneous_type (ty);
+ unsigned elems = element_count (ty);
+ for (i = 0; i < elems; i++)
+ {
+ void *reg = allocate_to_v (context, state);
+ copy_basic_type (reg, memory, type);
+ memory += get_basic_type_size (type);
+ }
+ }
+}
+
+/* Either allocate an appropriate register for the argument type, or if
+ none are available, allocate a stack slot and return a pointer
+ to the allocated space. */
+
+static void *
+allocate_to_register_or_stack (struct call_context *context,
+ unsigned char *stack,
+ struct arg_state *state,
+ unsigned short type)
+{
+ size_t alignment = get_basic_type_alignment (type);
+ size_t size = alignment;
+ switch (type)
+ {
+ case FFI_TYPE_FLOAT:
+ /* This is the only case for which the allocated stack size
+ should not match the alignment of the type. */
+ size = sizeof (UINT32);
+ /* Fall through. */
+ case FFI_TYPE_DOUBLE:
+ if (state->nsrn < N_V_ARG_REG)
+ return allocate_to_d (context, state);
+ state->nsrn = N_V_ARG_REG;
+ break;
+ case FFI_TYPE_LONGDOUBLE:
+ if (state->nsrn < N_V_ARG_REG)
+ return allocate_to_v (context, state);
+ state->nsrn = N_V_ARG_REG;
+ break;
+ case FFI_TYPE_UINT8:
+ case FFI_TYPE_SINT8:
+ case FFI_TYPE_UINT16:
+ case FFI_TYPE_SINT16:
+ case FFI_TYPE_UINT32:
+ case FFI_TYPE_SINT32:
+ case FFI_TYPE_INT:
+ case FFI_TYPE_POINTER:
+ case FFI_TYPE_UINT64:
+ case FFI_TYPE_SINT64:
+ if (state->ngrn < N_X_ARG_REG)
+ return allocate_to_x (context, state);
+ state->ngrn = N_X_ARG_REG;
+ break;
+ default:
+ FFI_ASSERT (0);
+ }
+
+ return allocate_to_stack (state, stack, alignment, size);
+}
+
+/* Copy a value to an appropriate register, or if none are
+ available, to the stack. */
+
+static void
+copy_to_register_or_stack (struct call_context *context,
+ unsigned char *stack,
+ struct arg_state *state,
+ void *value,
+ unsigned short type)
+{
+ copy_basic_type (
+ allocate_to_register_or_stack (context, stack, state, type),
+ value,
+ type);
+}
+
+/* Marshall the arguments from FFI representation to procedure call
+ context and stack. */
+
+static unsigned
+aarch64_prep_args (struct call_context *context, unsigned char *stack,
+ extended_cif *ecif)
+{
+ int i;
+ struct arg_state state;
+
+ arg_init (&state, ALIGN(ecif->cif->bytes, 16));
+
+ for (i = 0; i < ecif->cif->nargs; i++)
+ {
+ ffi_type *ty = ecif->cif->arg_types[i];
+ switch (ty->type)
+ {
+ case FFI_TYPE_VOID:
+ FFI_ASSERT (0);
+ break;
+
+ /* If the argument is a basic type the argument is allocated to an
+ appropriate register, or if none are available, to the stack. */
+ case FFI_TYPE_FLOAT:
+ case FFI_TYPE_DOUBLE:
+ case FFI_TYPE_LONGDOUBLE:
+ case FFI_TYPE_UINT8:
+ case FFI_TYPE_SINT8:
+ case FFI_TYPE_UINT16:
+ case FFI_TYPE_SINT16:
+ case FFI_TYPE_UINT32:
+ case FFI_TYPE_INT:
+ case FFI_TYPE_SINT32:
+ case FFI_TYPE_POINTER:
+ case FFI_TYPE_UINT64:
+ case FFI_TYPE_SINT64:
+ copy_to_register_or_stack (context, stack, &state,
+ ecif->avalue[i], ty->type);
+ break;
+
+ case FFI_TYPE_STRUCT:
+ if (is_hfa (ty))
+ {
+ copy_hfa_to_reg_or_stack (ecif->avalue[i], ty, context,
+ stack, &state);
+ }
+ else if (ty->size > 16)
+ {
+ /* If the argument is a composite type that is larger than 16
+ bytes, then the argument has been copied to memory, and
+ the argument is replaced by a pointer to the copy. */
+
+ copy_to_register_or_stack (context, stack, &state,
+ &(ecif->avalue[i]), FFI_TYPE_POINTER);
+ }
+ else if (available_x (&state) >= (ty->size + 7) / 8)
+ {
+ /* If the argument is a composite type and the size in
+ double-words is not more than the number of available
+ X registers, then the argument is copied into consecutive
+ X registers. */
+ int j;
+ for (j = 0; j < (ty->size + 7) / 8; j++)
+ {
+ memcpy (allocate_to_x (context, &state),
+ &(((UINT64 *) ecif->avalue[i])[j]),
+ sizeof (UINT64));
+ }
+ }
+ else
+ {
+ /* Otherwise, there are insufficient X registers. Further X
+ register allocations are prevented, the NSAA is adjusted
+ (by allocate_to_stack ()) and the argument is copied to
+ memory at the adjusted NSAA. */
+ state.ngrn = N_X_ARG_REG;
+
+ memcpy (allocate_to_stack (&state, stack, ty->alignment,
+ ty->size), ecif->avalue + i, ty->size);
+ }
+ break;
+
+ default:
+ FFI_ASSERT (0);
+ break;
+ }
+ }
+
+ return ecif->cif->aarch64_flags;
+}
+
+ffi_status
+ffi_prep_cif_machdep (ffi_cif *cif)
+{
+ /* Round the stack up to a multiple of the stack alignment requirement. */
+ cif->bytes =
+ (cif->bytes + (AARCH64_STACK_ALIGN - 1)) & ~ (AARCH64_STACK_ALIGN - 1);
+
+ /* Initialize our flags. We are interested if this CIF will touch a
+ vector register, if so we will enable context save and load to
+ those registers, otherwise not. This is intended to be friendly
+ to lazy float context switching in the kernel. */
+ cif->aarch64_flags = 0;
+
+ if (is_v_register_candidate (cif->rtype))
+ {
+ cif->aarch64_flags |= AARCH64_FFI_WITH_V;
+ }
+ else
+ {
+ int i;
+ for (i = 0; i < cif->nargs; i++)
+ if (is_v_register_candidate (cif->arg_types[i]))
+ {
+ cif->aarch64_flags |= AARCH64_FFI_WITH_V;
+ break;
+ }
+ }
+
+ return FFI_OK;
+}
+
+/* Call a function with the provided arguments and capture the return
+ value. */
+void
+ffi_call (ffi_cif *cif, void (*fn)(void), void *rvalue, void **avalue)
+{
+ extended_cif ecif;
+
+ ecif.cif = cif;
+ ecif.avalue = avalue;
+ ecif.rvalue = rvalue;
+
+ switch (cif->abi)
+ {
+ case FFI_SYSV:
+ {
+ struct call_context context;
+ unsigned stack_bytes;
+
+ /* Figure out the total amount of stack space we need, the
+ above call frame space needs to be 16 bytes aligned to
+ ensure correct alignment of the first object inserted in
+ that space hence the ALIGN applied to cif->bytes.*/
+ stack_bytes = ALIGN(cif->bytes, 16);
+
+ memset (&context, 0, sizeof (context));
+ if (is_register_candidate (cif->rtype))
+ {
+ ffi_call_SYSV (aarch64_prep_args, &context, &ecif, stack_bytes, fn);
+ switch (cif->rtype->type)
+ {
+ case FFI_TYPE_VOID:
+ case FFI_TYPE_FLOAT:
+ case FFI_TYPE_DOUBLE:
+ case FFI_TYPE_LONGDOUBLE:
+ case FFI_TYPE_UINT8:
+ case FFI_TYPE_SINT8:
+ case FFI_TYPE_UINT16:
+ case FFI_TYPE_SINT16:
+ case FFI_TYPE_UINT32:
+ case FFI_TYPE_SINT32:
+ case FFI_TYPE_POINTER:
+ case FFI_TYPE_UINT64:
+ case FFI_TYPE_INT:
+ case FFI_TYPE_SINT64:
+ {
+ void *addr = get_basic_type_addr (cif->rtype->type,
+ &context, 0);
+ copy_basic_type (rvalue, addr, cif->rtype->type);
+ break;
+ }
+
+ case FFI_TYPE_STRUCT:
+ if (is_hfa (cif->rtype))
+ {
+ int j;
+ unsigned short type = get_homogeneous_type (cif->rtype);
+ unsigned elems = element_count (cif->rtype);
+ for (j = 0; j < elems; j++)
+ {
+ void *reg = get_basic_type_addr (type, &context, j);
+ copy_basic_type (rvalue, reg, type);
+ rvalue += get_basic_type_size (type);
+ }
+ }
+ else if ((cif->rtype->size + 7) / 8 < N_X_ARG_REG)
+ {
+ unsigned size = ALIGN (cif->rtype->size, sizeof (UINT64));
+ memcpy (rvalue, get_x_addr (&context, 0), size);
+ }
+ else
+ {
+ FFI_ASSERT (0);
+ }
+ break;
+
+ default:
+ FFI_ASSERT (0);
+ break;
+ }
+ }
+ else
+ {
+ memcpy (get_x_addr (&context, 8), &rvalue, sizeof (UINT64));
+ ffi_call_SYSV (aarch64_prep_args, &context, &ecif,
+ stack_bytes, fn);
+ }
+ break;
+ }
+
+ default:
+ FFI_ASSERT (0);
+ break;
+ }
+}
+
+static unsigned char trampoline [] =
+{ 0x70, 0x00, 0x00, 0x58, /* ldr x16, 1f */
+ 0x91, 0x00, 0x00, 0x10, /* adr x17, 2f */
+ 0x00, 0x02, 0x1f, 0xd6 /* br x16 */
+};
+
+/* Build a trampoline. */
+
+#define FFI_INIT_TRAMPOLINE(TRAMP,FUN,CTX,FLAGS) \
+ ({unsigned char *__tramp = (unsigned char*)(TRAMP); \
+ UINT64 __fun = (UINT64)(FUN); \
+ UINT64 __ctx = (UINT64)(CTX); \
+ UINT64 __flags = (UINT64)(FLAGS); \
+ memcpy (__tramp, trampoline, sizeof (trampoline)); \
+ memcpy (__tramp + 12, &__fun, sizeof (__fun)); \
+ memcpy (__tramp + 20, &__ctx, sizeof (__ctx)); \
+ memcpy (__tramp + 28, &__flags, sizeof (__flags)); \
+ __clear_cache(__tramp, __tramp + FFI_TRAMPOLINE_SIZE); \
+ })
+
+ffi_status
+ffi_prep_closure_loc (ffi_closure* closure,
+ ffi_cif* cif,
+ void (*fun)(ffi_cif*,void*,void**,void*),
+ void *user_data,
+ void *codeloc)
+{
+ if (cif->abi != FFI_SYSV)
+ return FFI_BAD_ABI;
+
+ FFI_INIT_TRAMPOLINE (&closure->tramp[0], &ffi_closure_SYSV, codeloc,
+ cif->aarch64_flags);
+
+ closure->cif = cif;
+ closure->user_data = user_data;
+ closure->fun = fun;
+
+ return FFI_OK;
+}
+
+/* Primary handler to setup and invoke a function within a closure.
+
+ A closure when invoked enters via the assembler wrapper
+ ffi_closure_SYSV(). The wrapper allocates a call context on the
+ stack, saves the interesting registers (from the perspective of
+ the calling convention) into the context then passes control to
+ ffi_closure_SYSV_inner() passing the saved context and a pointer to
+ the stack at the point ffi_closure_SYSV() was invoked.
+
+ On the return path the assembler wrapper will reload call context
+ regsiters.
+
+ ffi_closure_SYSV_inner() marshalls the call context into ffi value
+ desriptors, invokes the wrapped function, then marshalls the return
+ value back into the call context. */
+
+void
+ffi_closure_SYSV_inner (ffi_closure *closure, struct call_context *context,
+ void *stack)
+{
+ ffi_cif *cif = closure->cif;
+ void **avalue = (void**) alloca (cif->nargs * sizeof (void*));
+ void *rvalue = NULL;
+ int i;
+ struct arg_state state;
+
+ arg_init (&state, ALIGN(cif->bytes, 16));
+
+ for (i = 0; i < cif->nargs; i++)
+ {
+ ffi_type *ty = cif->arg_types[i];
+
+ switch (ty->type)
+ {
+ case FFI_TYPE_VOID:
+ FFI_ASSERT (0);
+ break;
+
+ case FFI_TYPE_UINT8:
+ case FFI_TYPE_SINT8:
+ case FFI_TYPE_UINT16:
+ case FFI_TYPE_SINT16:
+ case FFI_TYPE_UINT32:
+ case FFI_TYPE_SINT32:
+ case FFI_TYPE_INT:
+ case FFI_TYPE_POINTER:
+ case FFI_TYPE_UINT64:
+ case FFI_TYPE_SINT64:
+ case FFI_TYPE_FLOAT:
+ case FFI_TYPE_DOUBLE:
+ case FFI_TYPE_LONGDOUBLE:
+ avalue[i] = allocate_to_register_or_stack (context, stack,
+ &state, ty->type);
+ break;
+
+ case FFI_TYPE_STRUCT:
+ if (is_hfa (ty))
+ {
+ unsigned n = element_count (ty);
+ if (available_v (&state) < n)
+ {
+ state.nsrn = N_V_ARG_REG;
+ avalue[i] = allocate_to_stack (&state, stack, ty->alignment,
+ ty->size);
+ }
+ else
+ {
+ switch (get_homogeneous_type (ty))
+ {
+ case FFI_TYPE_FLOAT:
+ {
+ /* Eeek! We need a pointer to the structure,
+ however the homogeneous float elements are
+ being passed in individual S registers,
+ therefore the structure is not represented as
+ a contiguous sequence of bytes in our saved
+ register context. We need to fake up a copy
+ of the structure layed out in memory
+ correctly. The fake can be tossed once the
+ closure function has returned hence alloca()
+ is sufficient. */
+ int j;
+ UINT32 *p = avalue[i] = alloca (ty->size);
+ for (j = 0; j < element_count (ty); j++)
+ memcpy (&p[j],
+ allocate_to_s (context, &state),
+ sizeof (*p));
+ break;
+ }
+
+ case FFI_TYPE_DOUBLE:
+ {
+ /* Eeek! We need a pointer to the structure,
+ however the homogeneous float elements are
+ being passed in individual S registers,
+ therefore the structure is not represented as
+ a contiguous sequence of bytes in our saved
+ register context. We need to fake up a copy
+ of the structure layed out in memory
+ correctly. The fake can be tossed once the
+ closure function has returned hence alloca()
+ is sufficient. */
+ int j;
+ UINT64 *p = avalue[i] = alloca (ty->size);
+ for (j = 0; j < element_count (ty); j++)
+ memcpy (&p[j],
+ allocate_to_d (context, &state),
+ sizeof (*p));
+ break;
+ }
+
+ case FFI_TYPE_LONGDOUBLE:
+ memcpy (&avalue[i],
+ allocate_to_v (context, &state),
+ sizeof (*avalue));
+ break;
+
+ default:
+ FFI_ASSERT (0);
+ break;
+ }
+ }
+ }
+ else if (ty->size > 16)
+ {
+ /* Replace Composite type of size greater than 16 with a
+ pointer. */
+ memcpy (&avalue[i],
+ allocate_to_register_or_stack (context, stack,
+ &state, FFI_TYPE_POINTER),
+ sizeof (avalue[i]));
+ }
+ else if (available_x (&state) >= (ty->size + 7) / 8)
+ {
+ avalue[i] = get_x_addr (context, state.ngrn);
+ state.ngrn += (ty->size + 7) / 8;
+ }
+ else
+ {
+ state.ngrn = N_X_ARG_REG;
+
+ avalue[i] = allocate_to_stack (&state, stack, ty->alignment,
+ ty->size);
+ }
+ break;
+
+ default:
+ FFI_ASSERT (0);
+ break;
+ }
+ }
+
+ /* Figure out where the return value will be passed, either in
+ registers or in a memory block allocated by the caller and passed
+ in x8. */
+
+ if (is_register_candidate (cif->rtype))
+ {
+ /* Register candidates are *always* returned in registers. */
+
+ /* Allocate a scratchpad for the return value, we will let the
+ callee scrible the result into the scratch pad then move the
+ contents into the appropriate return value location for the
+ call convention. */
+ rvalue = alloca (cif->rtype->size);
+ (closure->fun) (cif, rvalue, avalue, closure->user_data);
+
+ /* Copy the return value into the call context so that it is returned
+ as expected to our caller. */
+ switch (cif->rtype->type)
+ {
+ case FFI_TYPE_VOID:
+ break;
+
+ case FFI_TYPE_UINT8:
+ case FFI_TYPE_UINT16:
+ case FFI_TYPE_UINT32:
+ case FFI_TYPE_POINTER:
+ case FFI_TYPE_UINT64:
+ case FFI_TYPE_SINT8:
+ case FFI_TYPE_SINT16:
+ case FFI_TYPE_INT:
+ case FFI_TYPE_SINT32:
+ case FFI_TYPE_SINT64:
+ case FFI_TYPE_FLOAT:
+ case FFI_TYPE_DOUBLE:
+ case FFI_TYPE_LONGDOUBLE:
+ {
+ void *addr = get_basic_type_addr (cif->rtype->type, context, 0);
+ copy_basic_type (addr, rvalue, cif->rtype->type);
+ break;
+ }
+ case FFI_TYPE_STRUCT:
+ if (is_hfa (cif->rtype))
+ {
+ int i;
+ unsigned short type = get_homogeneous_type (cif->rtype);
+ unsigned elems = element_count (cif->rtype);
+ for (i = 0; i < elems; i++)
+ {
+ void *reg = get_basic_type_addr (type, context, i);
+ copy_basic_type (reg, rvalue, type);
+ rvalue += get_basic_type_size (type);
+ }
+ }
+ else if ((cif->rtype->size + 7) / 8 < N_X_ARG_REG)
+ {
+ unsigned size = ALIGN (cif->rtype->size, sizeof (UINT64)) ;
+ memcpy (get_x_addr (context, 0), rvalue, size);
+ }
+ else
+ {
+ FFI_ASSERT (0);
+ }
+ break;
+ default:
+ FFI_ASSERT (0);
+ break;
+ }
+ }
+ else
+ {
+ memcpy (&rvalue, get_x_addr (context, 8), sizeof (UINT64));
+ (closure->fun) (cif, rvalue, avalue, closure->user_data);
+ }
+}
+
View Lorry Controller Status