/Modules/_ctypes/libffi_msvc/win32.c
http://unladen-swallow.googlecode.com/ · C · 267 lines · 144 code · 40 blank · 83 comment · 0 complexity · 3edb1646d7a0551a10e31f9b60f4fa4d MD5 · raw file
- /* -----------------------------------------------------------------------
- win32.S - Copyright (c) 1996, 1998, 2001, 2002 Red Hat, Inc.
- Copyright (c) 2001 John Beniton
- Copyright (c) 2002 Ranjit Mathew
-
-
- X86 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 CYGNUS SOLUTIONS 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.
- ----------------------------------------------------------------------- */
- /* theller: almost verbatim translation from gas syntax to MSVC inline
- assembler code. */
- /* theller: ffi_call_SYSV and ffi_call_STDCALL now return an integer - the
- difference of the stack pointer before and after the function call. If
- everything is ok, zero is returned. If stdcall functions are passed the
- wrong number of arguments, the difference will be nonzero. */
- #include <ffi.h>
- #include <ffi_common.h>
- __declspec(naked) int
- ffi_call_SYSV(void (* prepfunc)(char *, extended_cif *), /* 8 */
- extended_cif *ecif, /* 12 */
- unsigned bytes, /* 16 */
- unsigned flags, /* 20 */
- unsigned *rvalue, /* 24 */
- void (*fn)()) /* 28 */
- {
- _asm {
- push ebp
- mov ebp, esp
- push esi // NEW: this register must be preserved across function calls
- // XXX SAVE ESP NOW!
- mov esi, esp // save stack pointer before the call
- // Make room for all of the new args.
- mov ecx, [ebp+16]
- sub esp, ecx // sub esp, bytes
-
- mov eax, esp
- // Place all of the ffi_prep_args in position
- push [ebp + 12] // ecif
- push eax
- call [ebp + 8] // prepfunc
- // Return stack to previous state and call the function
- add esp, 8
- // FIXME: Align the stack to a 128-bit boundary to avoid
- // potential performance hits.
- call [ebp + 28]
- // Remove the space we pushed for the args
- mov ecx, [ebp + 16]
- add esp, ecx
- // XXX ASSERT THAT ESP IS THE SAME NOW THAN BEFORE!
- sub esi, esp
- // Load %ecx with the return type code
- mov ecx, [ebp + 20]
- // If the return value pointer is NULL, assume no return value.
- /*
- Intel asm is weird. We have to explicitely specify 'DWORD PTR' in the nexr instruction,
- otherwise only one BYTE will be compared (instead of a DWORD)!
- */
- cmp DWORD PTR [ebp + 24], 0
- jne sc_retint
- // Even if there is no space for the return value, we are
- // obliged to handle floating-point values.
- cmp ecx, FFI_TYPE_FLOAT
- jne sc_noretval
- // fstp %st(0)
- fstp st(0)
- jmp sc_epilogue
- sc_retint:
- cmp ecx, FFI_TYPE_INT
- jne sc_retfloat
- // # Load %ecx with the pointer to storage for the return value
- mov ecx, [ebp + 24]
- mov [ecx + 0], eax
- jmp sc_epilogue
- sc_retfloat:
- cmp ecx, FFI_TYPE_FLOAT
- jne sc_retdouble
- // Load %ecx with the pointer to storage for the return value
- mov ecx, [ebp+24]
- // fstps (%ecx)
- fstp DWORD PTR [ecx]
- jmp sc_epilogue
- sc_retdouble:
- cmp ecx, FFI_TYPE_DOUBLE
- jne sc_retlongdouble
- // movl 24(%ebp),%ecx
- mov ecx, [ebp+24]
- fstp QWORD PTR [ecx]
- jmp sc_epilogue
- jmp sc_retlongdouble // avoid warning about unused label
- sc_retlongdouble:
- cmp ecx, FFI_TYPE_LONGDOUBLE
- jne sc_retint64
- // Load %ecx with the pointer to storage for the return value
- mov ecx, [ebp+24]
- // fstpt (%ecx)
- fstp QWORD PTR [ecx] /* XXX ??? */
- jmp sc_epilogue
- sc_retint64:
- cmp ecx, FFI_TYPE_SINT64
- jne sc_retstruct
- // Load %ecx with the pointer to storage for the return value
- mov ecx, [ebp+24]
- mov [ecx+0], eax
- mov [ecx+4], edx
- sc_retstruct:
- // Nothing to do!
- sc_noretval:
- sc_epilogue:
- mov eax, esi
- pop esi // NEW restore: must be preserved across function calls
- mov esp, ebp
- pop ebp
- ret
- }
- }
- __declspec(naked) int
- ffi_call_STDCALL(void (* prepfunc)(char *, extended_cif *), /* 8 */
- extended_cif *ecif, /* 12 */
- unsigned bytes, /* 16 */
- unsigned flags, /* 20 */
- unsigned *rvalue, /* 24 */
- void (*fn)()) /* 28 */
- {
- _asm {
- push ebp
- mov ebp, esp
- push esi // NEW: this register must be preserved across function calls
- // XXX SAVE ESP NOW!
- mov esi, esp
- // Make room for all of the new args.
- mov ecx, [ebp+16]
- sub esp, ecx
-
- mov eax, esp
- // Place all of the ffi_prep_args in position
- push [ebp + 12] // ecif
- push eax
- call [ebp + 8] // prepfunc
- // Return stack to previous state and call the function
- add esp, 8
- // FIXME: Align the stack to a 128-bit boundary to avoid
- // potential performance hits.
- call [ebp + 28]
- // stdcall functions pop arguments off the stack themselves
- // XXX IS ESP NOW THE SAME AS BEFORE?
- sub esi, esp
- // Load %ecx with the return type code
- mov ecx, [ebp + 20]
- // If the return value pointer is NULL, assume no return value.
- /*
- Intel asm is weird. We have to explicitely specify 'DWORD PTR' in the nexr instruction,
- otherwise only one BYTE will be compared (instead of a DWORD)!
- */
- cmp DWORD PTR [ebp + 24], 0
- jne sc_retint
- // Even if there is no space for the return value, we are
- // obliged to handle floating-point values.
- cmp ecx, FFI_TYPE_FLOAT
- jne sc_noretval
- // fstp %st(0)
- fstp st(0)
- jmp sc_epilogue
- sc_retint:
- cmp ecx, FFI_TYPE_INT
- jne sc_retfloat
- // # Load %ecx with the pointer to storage for the return value
- mov ecx, [ebp + 24]
- mov [ecx + 0], eax
- jmp sc_epilogue
- sc_retfloat:
- cmp ecx, FFI_TYPE_FLOAT
- jne sc_retdouble
- // Load %ecx with the pointer to storage for the return value
- mov ecx, [ebp+24]
- // fstps (%ecx)
- fstp DWORD PTR [ecx]
- jmp sc_epilogue
- sc_retdouble:
- cmp ecx, FFI_TYPE_DOUBLE
- jne sc_retlongdouble
- // movl 24(%ebp),%ecx
- mov ecx, [ebp+24]
- fstp QWORD PTR [ecx]
- jmp sc_epilogue
- jmp sc_retlongdouble // avoid warning about unused label
- sc_retlongdouble:
- cmp ecx, FFI_TYPE_LONGDOUBLE
- jne sc_retint64
- // Load %ecx with the pointer to storage for the return value
- mov ecx, [ebp+24]
- // fstpt (%ecx)
- fstp QWORD PTR [ecx] /* XXX ??? */
- jmp sc_epilogue
- sc_retint64:
- cmp ecx, FFI_TYPE_SINT64
- jne sc_retstruct
- // Load %ecx with the pointer to storage for the return value
- mov ecx, [ebp+24]
- mov [ecx+0], eax
- mov [ecx+4], edx
- sc_retstruct:
- // Nothing to do!
- sc_noretval:
- sc_epilogue:
- mov eax, esi
- pop esi // NEW restore: must be preserved across function calls
- mov esp, ebp
- pop ebp
- ret
- }
- }