src/loongarch64/ffi.c - third_party/libffi - Git at Google

 /* -----------------------------------------------------------------------
    ffi.c - Copyright (c) 2022 Xu Chenghua <xuchenghua@loongson.cn>
                          2022 Cheng Lulu <chenglulu@loongson.cn>
    Based on RISC-V port

    LoongArch 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 <tramp.h>

 #include <stdlib.h>
 #include <stdint.h>

 #if defined(__loongarch_soft_float)
 # define ABI_FRLEN 0
 #elif defined(__loongarch_single_float)
 # define ABI_FRLEN 32
 # define ABI_FLOAT float
 #elif defined(__loongarch_double_float)
 # define ABI_FRLEN 64
 # define ABI_FLOAT double
 #else
 #error unsupported LoongArch floating-point ABI
 #endif

 #define NARGREG 8
 #define STKALIGN 16
 #define MAXCOPYARG (2 * sizeof (double))

 /* call_context registers
    - 8 floating point parameter/result registers.
    - 8 integer parameter/result registers.
    - 2 registers used by the assembly code to in-place construct its own
      stack frame
      - frame register
      - return register
 */
 typedef struct call_context
 {
 #if !defined(__loongarch_soft_float)
   ABI_FLOAT fa[8];
 #endif
   size_t a[10];
 } call_context;

 typedef struct call_builder
 {
   call_context *aregs;
   int used_integer;
   int used_float;
   size_t *used_stack;
   size_t *stack;
   size_t next_struct_area;
 } call_builder;

 /* Integer (not pointer) less than ABI GRLEN.  */
 /* FFI_TYPE_INT does not appear to be used.  */
 #if __SIZEOF_POINTER__ == 8
 # define IS_INT(type) ((type) >= FFI_TYPE_UINT8 && (type) <= FFI_TYPE_SINT64)
 #else
 # define IS_INT(type) ((type) >= FFI_TYPE_UINT8 && (type) <= FFI_TYPE_SINT32)
 #endif

 #if ABI_FRLEN
 typedef struct float_struct_info
 {
   char as_elements;
   char type1;
   char offset2;
   char type2;
 } float_struct_info;

 #if ABI_FRLEN >= 64
 # define IS_FLOAT(type) ((type) >= FFI_TYPE_FLOAT && (type) <= FFI_TYPE_DOUBLE)
 #else
 # define IS_FLOAT(type) ((type) == FFI_TYPE_FLOAT)
 #endif

 static ffi_type **
 flatten_struct (ffi_type *in, ffi_type **out, ffi_type **out_end)
 {
   int i;

   if (out == out_end)
     return out;
   if (in->type != FFI_TYPE_STRUCT)
     *(out++) = in;
   else
     for (i = 0; in->elements[i]; i++)
       out = flatten_struct (in->elements[i], out, out_end);
   return out;
 }

 /* Structs with at most two fields after flattening, one of which is of
    floating point type, are passed in multiple registers if sufficient
    registers are available.  */
 static float_struct_info
 struct_passed_as_elements (call_builder *cb, ffi_type *top)
 {
   float_struct_info ret = {0, 0, 0, 0};
   ffi_type *fields[3];
   int num_floats, num_ints;
   int num_fields = flatten_struct (top, fields, fields + 3) - fields;

   if (num_fields == 1)
     {
       if (IS_FLOAT (fields[0]->type))
 	{
 	  ret.as_elements = 1;
 	  ret.type1 = fields[0]->type;
 	}
     }
   else if (num_fields == 2)
     {
       num_floats = IS_FLOAT (fields[0]->type) + IS_FLOAT (fields[1]->type);
       num_ints = IS_INT (fields[0]->type) + IS_INT (fields[1]->type);
       if (num_floats == 0 || num_floats + num_ints != 2)
 	return ret;
       if (cb->used_float + num_floats > NARGREG
 	  || cb->used_integer + (2 - num_floats) > NARGREG)
 	return ret;
       if (!IS_FLOAT (fields[0]->type) && !IS_FLOAT (fields[1]->type))
 	return ret;

       ret.type1 = fields[0]->type;
       ret.type2 = fields[1]->type;
       ret.offset2 = FFI_ALIGN (fields[0]->size, fields[1]->alignment);
       ret.as_elements = 1;
     }
   return ret;
 }
 #endif

 /* Allocates a single register, float register, or GRLEN-sized stack slot to a
    datum.  */
 static void
 marshal_atom (call_builder *cb, int type, void *data)
 {
   size_t value = 0;
   switch (type)
     {
     case FFI_TYPE_UINT8:
       value = *(uint8_t *) data;
       break;
     case FFI_TYPE_SINT8:
       value = *(int8_t *) data;
       break;
     case FFI_TYPE_UINT16:
       value = *(uint16_t *) data;
       break;
     case FFI_TYPE_SINT16:
       value = *(int16_t *) data;
       break;
     /* 32-bit quantities are always sign-extended in the ABI.  */
     case FFI_TYPE_UINT32:
       value = *(int32_t *) data;
       break;
     case FFI_TYPE_SINT32:
       value = *(int32_t *) data;
       break;
 #if __SIZEOF_POINTER__ == 8
     case FFI_TYPE_UINT64:
       value = *(uint64_t *) data;
       break;
     case FFI_TYPE_SINT64:
       value = *(int64_t *) data;
       break;
 #endif
     case FFI_TYPE_POINTER:
       value = *(size_t *) data;
       break;

 #if ABI_FRLEN >= 32
     case FFI_TYPE_FLOAT:
       *(float *)(cb->aregs->fa + cb->used_float++) = *(float *) data;
       return;
 #endif
 #if ABI_FRLEN >= 64
     case FFI_TYPE_DOUBLE:
       (cb->aregs->fa[cb->used_float++]) = *(double *) data;
       return;
 #endif
     default:
       FFI_ASSERT (0);
       break;
     }

   if (cb->used_integer == NARGREG)
     *cb->used_stack++ = value;
   else
     cb->aregs->a[cb->used_integer++] = value;
 }

 static void
 unmarshal_atom (call_builder *cb, int type, void *data)
 {
   size_t value;
   switch (type)
     {
 #if ABI_FRLEN >= 32
     case FFI_TYPE_FLOAT:
       *(float *) data = *(float *)(cb->aregs->fa + cb->used_float++);
       return;
 #endif
 #if ABI_FRLEN >= 64
     case FFI_TYPE_DOUBLE:
       *(double *) data = cb->aregs->fa[cb->used_float++];
       return;
 #endif
     }

   if (cb->used_integer == NARGREG)
     value = *cb->used_stack++;
   else
     value = cb->aregs->a[cb->used_integer++];

   switch (type)
     {
     case FFI_TYPE_UINT8:
     case FFI_TYPE_SINT8:
     case FFI_TYPE_UINT16:
     case FFI_TYPE_SINT16:
     case FFI_TYPE_UINT32:
     case FFI_TYPE_SINT32:
 #if __SIZEOF_POINTER__ == 8
     case FFI_TYPE_UINT64:
     case FFI_TYPE_SINT64:
 #endif
     case FFI_TYPE_POINTER:
       *(ffi_arg *)data = value;
       break;
     default:
       FFI_ASSERT (0);
       break;
     }
 }

 /* Allocate and copy a structure that is passed by value on the stack and
    return a pointer to it.  */
 static void *
 allocate_and_copy_struct_to_stack (call_builder *cb, void *data,
 				   ffi_type *type)
 {
   size_t dest = cb->next_struct_area - type->size;

   dest = FFI_ALIGN_DOWN (dest, type->alignment);
   cb->next_struct_area = dest;

   return memcpy ((char *)cb->stack + dest, data, type->size);
 }

 /* Adds an argument to a call, or a not by reference return value.  */
 static void
 marshal (call_builder *cb, ffi_type *type, int var, void *data)
 {
   size_t realign[2];

 #if ABI_FRLEN
   if (!var && type->type == FFI_TYPE_STRUCT)
     {
       float_struct_info fsi = struct_passed_as_elements (cb, type);
       if (fsi.as_elements)
 	{
 	  marshal_atom (cb, fsi.type1, data);
 	  if (fsi.offset2)
 	    marshal_atom (cb, fsi.type2, ((char *) data) + fsi.offset2);
 	  return;
 	}
     }

   if (!var && cb->used_float < NARGREG
       && IS_FLOAT (type->type))
     {
       marshal_atom (cb, type->type, data);
       return;
     }

   double promoted;
   if (var && type->type == FFI_TYPE_FLOAT)
     {
       /* C standard requires promoting float -> double for variable arg.  */
       promoted = *(float *) data;
       type = &ffi_type_double;
       data = &promoted;
     }
 #endif

   if (type->size > 2 * __SIZEOF_POINTER__)
     /* Pass by reference.  */
     {
       allocate_and_copy_struct_to_stack (cb, data, type);
       data = (char *)cb->stack + cb->next_struct_area;
       marshal_atom (cb, FFI_TYPE_POINTER, &data);
     }
   else if (IS_INT (type->type) || type->type == FFI_TYPE_POINTER)
     marshal_atom (cb, type->type, data);
   else
     {
       /* Overlong integers, soft-float floats, and structs without special
 	 float handling are treated identically from this point on.  */

       /* Variadics are aligned even in registers.  */
       if (type->alignment > __SIZEOF_POINTER__)
 	{
 	  if (var)
 	    cb->used_integer = FFI_ALIGN (cb->used_integer, 2);
 	  cb->used_stack
 	    = (size_t *) FFI_ALIGN (cb->used_stack, 2 * __SIZEOF_POINTER__);
 	}

       memcpy (realign, data, type->size);
       if (type->size > 0)
 	marshal_atom (cb, FFI_TYPE_POINTER, realign);
       if (type->size > __SIZEOF_POINTER__)
 	marshal_atom (cb, FFI_TYPE_POINTER, realign + 1);
     }
 }

 /* For arguments passed by reference returns the pointer, otherwise the arg
    is copied (up to MAXCOPYARG bytes).  */
 static void *
 unmarshal (call_builder *cb, ffi_type *type, int var, void *data)
 {
   size_t realign[2];
   void *pointer;

 #if ABI_FRLEN
   if (!var && type->type == FFI_TYPE_STRUCT)
     {
       float_struct_info fsi = struct_passed_as_elements (cb, type);
       if (fsi.as_elements)
 	{
 	  unmarshal_atom (cb, fsi.type1, data);
 	  if (fsi.offset2)
 	    unmarshal_atom (cb, fsi.type2, ((char *) data) + fsi.offset2);
 	  return data;
 	}
     }

   if (!var && cb->used_float < NARGREG
       && IS_FLOAT (type->type))
     {
       unmarshal_atom (cb, type->type, data);
       return data;
     }

   if (var && type->type == FFI_TYPE_FLOAT)
     {
       int m = cb->used_integer;
       void *promoted
 	= m < NARGREG ? cb->aregs->a + m : cb->used_stack + m - NARGREG + 1;
       *(float *) promoted = *(double *) promoted;
     }
 #endif

   if (type->size > 2 * __SIZEOF_POINTER__)
     {
       /* Pass by reference.  */
       unmarshal_atom (cb, FFI_TYPE_POINTER, (char *) &pointer);
       return pointer;
     }
   else if (IS_INT (type->type) || type->type == FFI_TYPE_POINTER)
     {
       unmarshal_atom (cb, type->type, data);
       return data;
     }
   else
     {
       /* Overlong integers, soft-float floats, and structs without special
 	 float handling are treated identically from this point on.  */

       /* Variadics are aligned even in registers.  */
       if (type->alignment > __SIZEOF_POINTER__)
 	{
 	  if (var)
 	    cb->used_integer = FFI_ALIGN (cb->used_integer, 2);
 	  cb->used_stack
 	    = (size_t *) FFI_ALIGN (cb->used_stack, 2 * __SIZEOF_POINTER__);
 	}

       if (type->size > 0)
 	unmarshal_atom (cb, FFI_TYPE_POINTER, realign);
       if (type->size > __SIZEOF_POINTER__)
 	unmarshal_atom (cb, FFI_TYPE_POINTER, realign + 1);
       memcpy (data, realign, type->size);
       return data;
     }
 }

 static int
 passed_by_ref (call_builder *cb, ffi_type *type, int var)
 {
 #if ABI_FRLEN
   if (!var && type->type == FFI_TYPE_STRUCT)
     {
       float_struct_info fsi = struct_passed_as_elements (cb, type);
       if (fsi.as_elements)
 	return 0;
     }
 #endif

   return type->size > 2 * __SIZEOF_POINTER__;
 }

 /* Perform machine dependent cif processing.  */
 ffi_status
 ffi_prep_cif_machdep (ffi_cif *cif)
 {
   cif->loongarch_nfixedargs = cif->nargs;
   return FFI_OK;
 }

 /* Perform machine dependent cif processing when we have a variadic
    function.  */
 ffi_status
 ffi_prep_cif_machdep_var (ffi_cif *cif, unsigned int nfixedargs,
 			  unsigned int ntotalargs)
 {
   cif->loongarch_nfixedargs = nfixedargs;
   return FFI_OK;
 }

 /* Low level routine for calling functions.  */
 extern void ffi_call_asm (void *stack, struct call_context *regs,
 			  void (*fn) (void), void *closure) FFI_HIDDEN;

 static void
 ffi_call_int (ffi_cif *cif, void (*fn) (void), void *rvalue, void **avalue,
 	      void *closure)
 {
   /* This is a conservative estimate, assuming a complex return value and
      that all remaining arguments are long long / __int128 */
   size_t arg_bytes = cif->bytes;
   size_t rval_bytes = 0;
   if (rvalue == NULL && cif->rtype->size > 2 * __SIZEOF_POINTER__)
     rval_bytes = FFI_ALIGN (cif->rtype->size, STKALIGN);
   size_t alloc_size = arg_bytes + rval_bytes + sizeof (call_context);

   /* The assembly code will deallocate all stack data at lower addresses
      than the argument region, so we need to allocate the frame and the
      return value after the arguments in a single allocation.  */
   size_t alloc_base;
   /* Argument region must be 16-byte aligned in LP64 ABIs.  */
   if (_Alignof(max_align_t) >= STKALIGN)
     /* Since sizeof long double is normally 16, the compiler will
        guarantee alloca alignment to at least that much.  */
     alloc_base = (size_t) alloca (alloc_size);
   else
     alloc_base = FFI_ALIGN (alloca (alloc_size + STKALIGN - 1), STKALIGN);

   if (rval_bytes)
     rvalue = (void *) (alloc_base + arg_bytes);

   call_builder cb;
   cb.used_float = cb.used_integer = 0;
   cb.aregs = (call_context *) (alloc_base + arg_bytes + rval_bytes);
   cb.used_stack = (void *) alloc_base;
   cb.stack = (void *) alloc_base;
   cb.next_struct_area = arg_bytes;

   int return_by_ref = passed_by_ref (&cb, cif->rtype, 0);
   if (return_by_ref)
     cb.aregs->a[cb.used_integer++] = (size_t)rvalue;

   int i;
   for (i = 0; i < cif->nargs; i++)
     marshal (&cb, cif->arg_types[i], i >= cif->loongarch_nfixedargs,
 	     avalue[i]);

   ffi_call_asm ((void *) alloc_base, cb.aregs, fn, closure);

   cb.used_float = cb.used_integer = 0;
   if (!return_by_ref && rvalue)
     unmarshal (&cb, cif->rtype, 0, rvalue);
 }

 void
 ffi_call (ffi_cif *cif, void (*fn) (void), void *rvalue, void **avalue)
 {
   ffi_call_int (cif, fn, rvalue, avalue, NULL);
 }

 void
 ffi_call_go (ffi_cif *cif, void (*fn) (void), void *rvalue, void **avalue,
 	     void *closure)
 {
   ffi_call_int (cif, fn, rvalue, avalue, closure);
 }

 extern void ffi_closure_asm (void) FFI_HIDDEN;

 ffi_status
 ffi_prep_closure_loc (ffi_closure *closure, ffi_cif *cif,
 		      void (*fun) (ffi_cif *, void *, void **, void *),
 		      void *user_data, void *codeloc)
 {
   uint32_t *tramp = (uint32_t *) &closure->tramp[0];
   uint64_t fn = (uint64_t) (uintptr_t) ffi_closure_asm;

   if (cif->abi <= FFI_FIRST_ABI || cif->abi >= FFI_LAST_ABI)
     return FFI_BAD_ABI;

 #if defined(FFI_EXEC_STATIC_TRAMP)
   if (ffi_tramp_is_present(closure))
     {
       ffi_tramp_set_parms (closure->ftramp, ffi_closure_asm, closure);
       goto out;
     }
 #endif

   /* Fill the dynamic trampoline.  We will call ffi_closure_inner with codeloc,
      not closure, but as long as the memory is readable it should work.  */
   tramp[0] = 0x1800000c; /* pcaddi $t0, 0 (i.e. $t0 <- tramp) */
   tramp[1] = 0x28c0418d; /* ld.d   $t1, $t0, 16 */
   tramp[2] = 0x4c0001a0; /* jirl   $zero, $t1, 0 */
   tramp[3] = 0x03400000; /* nop */
   tramp[4] = fn;
   tramp[5] = fn >> 32;

   __builtin___clear_cache (codeloc, codeloc + FFI_TRAMPOLINE_SIZE);

 #if defined(FFI_EXEC_STATIC_TRAMP)
 out:
 #endif
   closure->cif = cif;
   closure->fun = fun;
   closure->user_data = user_data;

   return FFI_OK;
 }

 extern void ffi_go_closure_asm (void) FFI_HIDDEN;

 ffi_status
 ffi_prep_go_closure (ffi_go_closure *closure, ffi_cif *cif,
 		     void (*fun) (ffi_cif *, void *, void **, void *))
 {
   if (cif->abi <= FFI_FIRST_ABI || cif->abi >= FFI_LAST_ABI)
     return FFI_BAD_ABI;

   closure->tramp = (void *) ffi_go_closure_asm;
   closure->cif = cif;
   closure->fun = fun;
   return FFI_OK;
 }

 /* Called by the assembly code with aregs pointing to saved argument registers
    and stack pointing to the stacked arguments.  Return values passed in
    registers will be reloaded from aregs.  */
 void FFI_HIDDEN
 ffi_closure_inner (ffi_cif *cif,
 		   void (*fun) (ffi_cif *, void *, void **, void *),
 		   void *user_data, size_t *stack, call_context *aregs)
 {
   void **avalue = alloca (cif->nargs * sizeof (void *));
   /* Storage for arguments which will be copied by unmarshal().  We could
      theoretically avoid the copies in many cases and use at most 128 bytes
      of memory, but allocating disjoint storage for each argument is
      simpler.  */
   char *astorage = alloca (cif->nargs * MAXCOPYARG);
   void *rvalue;
   call_builder cb;
   int return_by_ref;
   int i;

   cb.aregs = aregs;
   cb.used_integer = cb.used_float = 0;
   cb.used_stack = stack;

   return_by_ref = passed_by_ref (&cb, cif->rtype, 0);
   if (return_by_ref)
     unmarshal (&cb, &ffi_type_pointer, 0, &rvalue);
   else
     rvalue = alloca (cif->rtype->size);

   for (i = 0; i < cif->nargs; i++)
     avalue[i]
       = unmarshal (&cb, cif->arg_types[i], i >= cif->loongarch_nfixedargs,
 		   astorage + i * MAXCOPYARG);

   fun (cif, rvalue, avalue, user_data);

   if (!return_by_ref && cif->rtype->type != FFI_TYPE_VOID)
     {
       cb.used_integer = cb.used_float = 0;
       marshal (&cb, cif->rtype, 0, rvalue);
     }
 }

 #if defined(FFI_EXEC_STATIC_TRAMP)
 void *
 ffi_tramp_arch (size_t *tramp_size, size_t *map_size)
 {
   extern void *trampoline_code_table;

   *tramp_size = 16;
   /* A mapping size of 64K is chosen to cover the page sizes of 4K, 16K, and
      64K.  */
   *map_size = 1 << 16;
   return &trampoline_code_table;
 }
 #endif
	/* -----------------------------------------------------------------------
	ffi.c - Copyright (c) 2022 Xu Chenghua <xuchenghua@loongson.cn>
	2022 Cheng Lulu <chenglulu@loongson.cn>
	Based on RISC-V port

	LoongArch 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 <tramp.h>

	#include <stdlib.h>
	#include <stdint.h>

	#if defined(__loongarch_soft_float)
	# define ABI_FRLEN 0
	#elif defined(__loongarch_single_float)
	# define ABI_FRLEN 32
	# define ABI_FLOAT float
	#elif defined(__loongarch_double_float)
	# define ABI_FRLEN 64
	# define ABI_FLOAT double
	#else
	#error unsupported LoongArch floating-point ABI
	#endif

	#define NARGREG 8
	#define STKALIGN 16
	#define MAXCOPYARG (2 * sizeof (double))

	/* call_context registers
	- 8 floating point parameter/result registers.
	- 8 integer parameter/result registers.
	- 2 registers used by the assembly code to in-place construct its own
	stack frame
	- frame register
	- return register
	*/
	typedef struct call_context
	{
	#if !defined(__loongarch_soft_float)
	ABI_FLOAT fa[8];
	#endif
	size_t a[10];
	} call_context;

	typedef struct call_builder
	{
	call_context *aregs;
	int used_integer;
	int used_float;
	size_t *used_stack;
	size_t *stack;
	size_t next_struct_area;
	} call_builder;

	/* Integer (not pointer) less than ABI GRLEN. */
	/* FFI_TYPE_INT does not appear to be used. */
	#if __SIZEOF_POINTER__ == 8
	# define IS_INT(type) ((type) >= FFI_TYPE_UINT8 && (type) <= FFI_TYPE_SINT64)
	#else
	# define IS_INT(type) ((type) >= FFI_TYPE_UINT8 && (type) <= FFI_TYPE_SINT32)
	#endif

	#if ABI_FRLEN
	typedef struct float_struct_info
	{
	char as_elements;
	char type1;
	char offset2;
	char type2;
	} float_struct_info;

	#if ABI_FRLEN >= 64
	# define IS_FLOAT(type) ((type) >= FFI_TYPE_FLOAT && (type) <= FFI_TYPE_DOUBLE)
	#else
	# define IS_FLOAT(type) ((type) == FFI_TYPE_FLOAT)
	#endif

	static ffi_type **
	flatten_struct (ffi_type in, ffi_type out, ffi_type *out_end)
	{
	int i;

	if (out == out_end)
	return out;
	if (in->type != FFI_TYPE_STRUCT)
	*(out++) = in;
	else
	for (i = 0; in->elements[i]; i++)
	out = flatten_struct (in->elements[i], out, out_end);
	return out;
	}

	/* Structs with at most two fields after flattening, one of which is of
	floating point type, are passed in multiple registers if sufficient
	registers are available. */
	static float_struct_info
	struct_passed_as_elements (call_builder cb, ffi_type top)
	{
	float_struct_info ret = {0, 0, 0, 0};
	ffi_type *fields[3];
	int num_floats, num_ints;
	int num_fields = flatten_struct (top, fields, fields + 3) - fields;

	if (num_fields == 1)
	{
	if (IS_FLOAT (fields[0]->type))
	{
	ret.as_elements = 1;
	ret.type1 = fields[0]->type;
	}
	}
	else if (num_fields == 2)
	{
	num_floats = IS_FLOAT (fields[0]->type) + IS_FLOAT (fields[1]->type);
	num_ints = IS_INT (fields[0]->type) + IS_INT (fields[1]->type);
	if (num_floats == 0 \|\| num_floats + num_ints != 2)
	return ret;
	if (cb->used_float + num_floats > NARGREG
	\|\| cb->used_integer + (2 - num_floats) > NARGREG)
	return ret;
	if (!IS_FLOAT (fields[0]->type) && !IS_FLOAT (fields[1]->type))
	return ret;

	ret.type1 = fields[0]->type;
	ret.type2 = fields[1]->type;
	ret.offset2 = FFI_ALIGN (fields[0]->size, fields[1]->alignment);
	ret.as_elements = 1;
	}
	return ret;
	}
	#endif

	/* Allocates a single register, float register, or GRLEN-sized stack slot to a
	datum. */
	static void
	marshal_atom (call_builder cb, int type, void data)
	{
	size_t value = 0;
	switch (type)
	{
	case FFI_TYPE_UINT8:
	value = (uint8_t ) data;
	break;
	case FFI_TYPE_SINT8:
	value = (int8_t ) data;
	break;
	case FFI_TYPE_UINT16:
	value = (uint16_t ) data;
	break;
	case FFI_TYPE_SINT16:
	value = (int16_t ) data;
	break;
	/* 32-bit quantities are always sign-extended in the ABI. */
	case FFI_TYPE_UINT32:
	value = (int32_t ) data;
	break;
	case FFI_TYPE_SINT32:
	value = (int32_t ) data;
	break;
	#if __SIZEOF_POINTER__ == 8
	case FFI_TYPE_UINT64:
	value = (uint64_t ) data;
	break;
	case FFI_TYPE_SINT64:
	value = (int64_t ) data;
	break;
	#endif
	case FFI_TYPE_POINTER:
	value = (size_t ) data;
	break;

	#if ABI_FRLEN >= 32
	case FFI_TYPE_FLOAT:
	(float )(cb->aregs->fa + cb->used_float++) = (float ) data;
	return;
	#endif
	#if ABI_FRLEN >= 64
	case FFI_TYPE_DOUBLE:
	(cb->aregs->fa[cb->used_float++]) = (double ) data;
	return;
	#endif
	default:
	FFI_ASSERT (0);
	break;
	}

	if (cb->used_integer == NARGREG)
	*cb->used_stack++ = value;
	else
	cb->aregs->a[cb->used_integer++] = value;
	}

	static void
	unmarshal_atom (call_builder cb, int type, void data)
	{
	size_t value;
	switch (type)
	{
	#if ABI_FRLEN >= 32
	case FFI_TYPE_FLOAT:
	(float ) data = (float )(cb->aregs->fa + cb->used_float++);
	return;
	#endif
	#if ABI_FRLEN >= 64
	case FFI_TYPE_DOUBLE:
	(double ) data = cb->aregs->fa[cb->used_float++];
	return;
	#endif
	}

	if (cb->used_integer == NARGREG)
	value = *cb->used_stack++;
	else
	value = cb->aregs->a[cb->used_integer++];

	switch (type)
	{
	case FFI_TYPE_UINT8:
	case FFI_TYPE_SINT8:
	case FFI_TYPE_UINT16:
	case FFI_TYPE_SINT16:
	case FFI_TYPE_UINT32:
	case FFI_TYPE_SINT32:
	#if __SIZEOF_POINTER__ == 8
	case FFI_TYPE_UINT64:
	case FFI_TYPE_SINT64:
	#endif
	case FFI_TYPE_POINTER:
	(ffi_arg )data = value;
	break;
	default:
	FFI_ASSERT (0);
	break;
	}
	}

	/* Allocate and copy a structure that is passed by value on the stack and
	return a pointer to it. */
	static void *
	allocate_and_copy_struct_to_stack (call_builder cb, void data,
	ffi_type *type)
	{
	size_t dest = cb->next_struct_area - type->size;

	dest = FFI_ALIGN_DOWN (dest, type->alignment);
	cb->next_struct_area = dest;

	return memcpy ((char *)cb->stack + dest, data, type->size);
	}

	/* Adds an argument to a call, or a not by reference return value. */
	static void
	marshal (call_builder cb, ffi_type type, int var, void *data)
	{
	size_t realign[2];

	#if ABI_FRLEN
	if (!var && type->type == FFI_TYPE_STRUCT)
	{
	float_struct_info fsi = struct_passed_as_elements (cb, type);
	if (fsi.as_elements)
	{
	marshal_atom (cb, fsi.type1, data);
	if (fsi.offset2)
	marshal_atom (cb, fsi.type2, ((char *) data) + fsi.offset2);
	return;
	}
	}

	if (!var && cb->used_float < NARGREG
	&& IS_FLOAT (type->type))
	{
	marshal_atom (cb, type->type, data);
	return;
	}

	double promoted;
	if (var && type->type == FFI_TYPE_FLOAT)
	{
	/* C standard requires promoting float -> double for variable arg. */
	promoted = (float ) data;
	type = &ffi_type_double;
	data = &promoted;
	}
	#endif

	if (type->size > 2 * __SIZEOF_POINTER__)
	/* Pass by reference. */
	{
	allocate_and_copy_struct_to_stack (cb, data, type);
	data = (char *)cb->stack + cb->next_struct_area;
	marshal_atom (cb, FFI_TYPE_POINTER, &data);
	}
	else if (IS_INT (type->type) \|\| type->type == FFI_TYPE_POINTER)
	marshal_atom (cb, type->type, data);
	else
	{
	/* Overlong integers, soft-float floats, and structs without special
	float handling are treated identically from this point on. */

	/* Variadics are aligned even in registers. */
	if (type->alignment > __SIZEOF_POINTER__)
	{
	if (var)
	cb->used_integer = FFI_ALIGN (cb->used_integer, 2);
	cb->used_stack
	= (size_t ) FFI_ALIGN (cb->used_stack, 2 __SIZEOF_POINTER__);
	}

	memcpy (realign, data, type->size);
	if (type->size > 0)
	marshal_atom (cb, FFI_TYPE_POINTER, realign);
	if (type->size > __SIZEOF_POINTER__)
	marshal_atom (cb, FFI_TYPE_POINTER, realign + 1);
	}
	}

	/* For arguments passed by reference returns the pointer, otherwise the arg
	is copied (up to MAXCOPYARG bytes). */
	static void *
	unmarshal (call_builder cb, ffi_type type, int var, void *data)
	{
	size_t realign[2];
	void *pointer;

	#if ABI_FRLEN
	if (!var && type->type == FFI_TYPE_STRUCT)
	{
	float_struct_info fsi = struct_passed_as_elements (cb, type);
	if (fsi.as_elements)
	{
	unmarshal_atom (cb, fsi.type1, data);
	if (fsi.offset2)
	unmarshal_atom (cb, fsi.type2, ((char *) data) + fsi.offset2);
	return data;
	}
	}

	if (!var && cb->used_float < NARGREG
	&& IS_FLOAT (type->type))
	{
	unmarshal_atom (cb, type->type, data);
	return data;
	}

	if (var && type->type == FFI_TYPE_FLOAT)
	{
	int m = cb->used_integer;
	void *promoted
	= m < NARGREG ? cb->aregs->a + m : cb->used_stack + m - NARGREG + 1;
	(float ) promoted = (double ) promoted;
	}
	#endif

	if (type->size > 2 * __SIZEOF_POINTER__)
	{
	/* Pass by reference. */
	unmarshal_atom (cb, FFI_TYPE_POINTER, (char *) &pointer);
	return pointer;
	}
	else if (IS_INT (type->type) \|\| type->type == FFI_TYPE_POINTER)
	{
	unmarshal_atom (cb, type->type, data);
	return data;
	}
	else
	{
	/* Overlong integers, soft-float floats, and structs without special
	float handling are treated identically from this point on. */

	/* Variadics are aligned even in registers. */
	if (type->alignment > __SIZEOF_POINTER__)
	{
	if (var)
	cb->used_integer = FFI_ALIGN (cb->used_integer, 2);
	cb->used_stack
	= (size_t ) FFI_ALIGN (cb->used_stack, 2 __SIZEOF_POINTER__);
	}

	if (type->size > 0)
	unmarshal_atom (cb, FFI_TYPE_POINTER, realign);
	if (type->size > __SIZEOF_POINTER__)
	unmarshal_atom (cb, FFI_TYPE_POINTER, realign + 1);
	memcpy (data, realign, type->size);
	return data;
	}
	}

	static int
	passed_by_ref (call_builder cb, ffi_type type, int var)
	{
	#if ABI_FRLEN
	if (!var && type->type == FFI_TYPE_STRUCT)
	{
	float_struct_info fsi = struct_passed_as_elements (cb, type);
	if (fsi.as_elements)
	return 0;
	}
	#endif

	return type->size > 2 * __SIZEOF_POINTER__;
	}

	/* Perform machine dependent cif processing. */
	ffi_status
	ffi_prep_cif_machdep (ffi_cif *cif)
	{
	cif->loongarch_nfixedargs = cif->nargs;
	return FFI_OK;
	}

	/* Perform machine dependent cif processing when we have a variadic
	function. */
	ffi_status
	ffi_prep_cif_machdep_var (ffi_cif *cif, unsigned int nfixedargs,
	unsigned int ntotalargs)
	{
	cif->loongarch_nfixedargs = nfixedargs;
	return FFI_OK;
	}

	/* Low level routine for calling functions. */
	extern void ffi_call_asm (void stack, struct call_context regs,
	void (fn) (void), void closure) FFI_HIDDEN;

	static void
	ffi_call_int (ffi_cif cif, void (fn) (void), void rvalue, void *avalue,
	void *closure)
	{
	/* This is a conservative estimate, assuming a complex return value and
	that all remaining arguments are long long / __int128 */
	size_t arg_bytes = cif->bytes;
	size_t rval_bytes = 0;
	if (rvalue == NULL && cif->rtype->size > 2 * __SIZEOF_POINTER__)
	rval_bytes = FFI_ALIGN (cif->rtype->size, STKALIGN);
	size_t alloc_size = arg_bytes + rval_bytes + sizeof (call_context);

	/* The assembly code will deallocate all stack data at lower addresses
	than the argument region, so we need to allocate the frame and the
	return value after the arguments in a single allocation. */
	size_t alloc_base;
	/* Argument region must be 16-byte aligned in LP64 ABIs. */
	if (_Alignof(max_align_t) >= STKALIGN)
	/* Since sizeof long double is normally 16, the compiler will
	guarantee alloca alignment to at least that much. */
	alloc_base = (size_t) alloca (alloc_size);
	else
	alloc_base = FFI_ALIGN (alloca (alloc_size + STKALIGN - 1), STKALIGN);

	if (rval_bytes)
	rvalue = (void *) (alloc_base + arg_bytes);

	call_builder cb;
	cb.used_float = cb.used_integer = 0;
	cb.aregs = (call_context *) (alloc_base + arg_bytes + rval_bytes);
	cb.used_stack = (void *) alloc_base;
	cb.stack = (void *) alloc_base;
	cb.next_struct_area = arg_bytes;

	int return_by_ref = passed_by_ref (&cb, cif->rtype, 0);
	if (return_by_ref)
	cb.aregs->a[cb.used_integer++] = (size_t)rvalue;

	int i;
	for (i = 0; i < cif->nargs; i++)
	marshal (&cb, cif->arg_types[i], i >= cif->loongarch_nfixedargs,
	avalue[i]);

	ffi_call_asm ((void *) alloc_base, cb.aregs, fn, closure);

	cb.used_float = cb.used_integer = 0;
	if (!return_by_ref && rvalue)
	unmarshal (&cb, cif->rtype, 0, rvalue);
	}

	void
	ffi_call (ffi_cif cif, void (fn) (void), void rvalue, void *avalue)
	{
	ffi_call_int (cif, fn, rvalue, avalue, NULL);
	}

	void
	ffi_call_go (ffi_cif cif, void (fn) (void), void rvalue, void *avalue,
	void *closure)
	{
	ffi_call_int (cif, fn, rvalue, avalue, closure);
	}

	extern void ffi_closure_asm (void) FFI_HIDDEN;

	ffi_status
	ffi_prep_closure_loc (ffi_closure closure, ffi_cif cif,
	void (fun) (ffi_cif , void , void , void ),
	void user_data, void codeloc)
	{
	uint32_t tramp = (uint32_t ) &closure->tramp[0];
	uint64_t fn = (uint64_t) (uintptr_t) ffi_closure_asm;

	if (cif->abi <= FFI_FIRST_ABI \|\| cif->abi >= FFI_LAST_ABI)
	return FFI_BAD_ABI;

	#if defined(FFI_EXEC_STATIC_TRAMP)
	if (ffi_tramp_is_present(closure))
	{
	ffi_tramp_set_parms (closure->ftramp, ffi_closure_asm, closure);
	goto out;
	}
	#endif

	/* Fill the dynamic trampoline. We will call ffi_closure_inner with codeloc,
	not closure, but as long as the memory is readable it should work. */
	tramp[0] = 0x1800000c; /* pcaddi $t0, 0 (i.e. $t0 <- tramp) */
	tramp[1] = 0x28c0418d; /* ld.d $t1, $t0, 16 */
	tramp[2] = 0x4c0001a0; /* jirl $zero, $t1, 0 */
	tramp[3] = 0x03400000; /* nop */
	tramp[4] = fn;
	tramp[5] = fn >> 32;

	__builtin___clear_cache (codeloc, codeloc + FFI_TRAMPOLINE_SIZE);

	#if defined(FFI_EXEC_STATIC_TRAMP)
	out:
	#endif
	closure->cif = cif;
	closure->fun = fun;
	closure->user_data = user_data;

	return FFI_OK;
	}

	extern void ffi_go_closure_asm (void) FFI_HIDDEN;

	ffi_status
	ffi_prep_go_closure (ffi_go_closure closure, ffi_cif cif,
	void (fun) (ffi_cif , void , void , void ))
	{
	if (cif->abi <= FFI_FIRST_ABI \|\| cif->abi >= FFI_LAST_ABI)
	return FFI_BAD_ABI;

	closure->tramp = (void *) ffi_go_closure_asm;
	closure->cif = cif;
	closure->fun = fun;
	return FFI_OK;
	}

	/* Called by the assembly code with aregs pointing to saved argument registers
	and stack pointing to the stacked arguments. Return values passed in
	registers will be reloaded from aregs. */
	void FFI_HIDDEN
	ffi_closure_inner (ffi_cif *cif,
	void (fun) (ffi_cif , void , void , void ),
	void user_data, size_t stack, call_context *aregs)
	{
	void *avalue = alloca (cif->nargs sizeof (void *));
	/* Storage for arguments which will be copied by unmarshal(). We could
	theoretically avoid the copies in many cases and use at most 128 bytes
	of memory, but allocating disjoint storage for each argument is
	simpler. */
	char astorage = alloca (cif->nargs MAXCOPYARG);
	void *rvalue;
	call_builder cb;
	int return_by_ref;
	int i;

	cb.aregs = aregs;
	cb.used_integer = cb.used_float = 0;
	cb.used_stack = stack;

	return_by_ref = passed_by_ref (&cb, cif->rtype, 0);
	if (return_by_ref)
	unmarshal (&cb, &ffi_type_pointer, 0, &rvalue);
	else
	rvalue = alloca (cif->rtype->size);

	for (i = 0; i < cif->nargs; i++)
	avalue[i]
	= unmarshal (&cb, cif->arg_types[i], i >= cif->loongarch_nfixedargs,
	astorage + i * MAXCOPYARG);

	fun (cif, rvalue, avalue, user_data);

	if (!return_by_ref && cif->rtype->type != FFI_TYPE_VOID)
	{
	cb.used_integer = cb.used_float = 0;
	marshal (&cb, cif->rtype, 0, rvalue);
	}
	}

	#if defined(FFI_EXEC_STATIC_TRAMP)
	void *
	ffi_tramp_arch (size_t tramp_size, size_t map_size)
	{
	extern void *trampoline_code_table;

	*tramp_size = 16;
	/* A mapping size of 64K is chosen to cover the page sizes of 4K, 16K, and
	64K. */
	*map_size = 1 << 16;
	return &trampoline_code_table;
	}
	#endif