diff options
Diffstat (limited to 'c/libffi_x86_x64/win32.c')
| -rw-r--r-- | c/libffi_x86_x64/win32.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/c/libffi_x86_x64/win32.c b/c/libffi_x86_x64/win32.c new file mode 100644 index 0000000..d1149a8 --- /dev/null +++ b/c/libffi_x86_x64/win32.c @@ -0,0 +1,162 @@ +/* ----------------------------------------------------------------------- + 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_x86 now returns 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_x86(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] + +// Load ecif->cif->abi + mov ecx, [ebp + 12] + mov ecx, [ecx]ecif.cif + mov ecx, [ecx]ecif.cif.abi + + cmp ecx, FFI_STDCALL + je noclean +// STDCALL: Remove the space we pushed for the args + mov ecx, [ebp + 16] + add esp, ecx +// CDECL: Caller has already cleaned the stack +noclean: +// Check that esp has the same value 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 + } +} |