This refactoring should make it easier to add new calling conventions.

Replace ffi_call_STDCALL and ffi_call_SYSV by a ffi_call_x86 function
that cleans up the stack when FFI_SYSV is used, and does nothing for
FFI_STDCALL.

Remove libffi_msvc\win32.S, which is out of date and also unused; it
was only used for building ctypes with the MingW compiler.

3 files changed, 29 insertions, 400 deletions

diff --git a/Modules/_ctypes/libffi_msvc/ffi.c b/Modules/_ctypes/libffi_msvc/ffi.c
index 279b66b..763d179 100644
--- a/Modules/_ctypes/libffi_msvc/ffi.c
+++ b/Modules/_ctypes/libffi_msvc/ffi.c
@@ -148,27 +148,12 @@ ffi_status ffi_prep_cif_machdep(ffi_cif *cif)
 }
 
 #ifdef _WIN32
-/*@-declundef@*/
-/*@-exportheader@*/
-extern int
-ffi_call_SYSV(void (*)(char *, extended_cif *), 
-	      /*@out@*/ extended_cif *, 
-	      unsigned, unsigned, 
-	      /*@out@*/ unsigned *, 
-	      void (*fn)());
-/*@=declundef@*/
-/*@=exportheader@*/
-
-/*@-declundef@*/
-/*@-exportheader@*/
 extern int
-ffi_call_STDCALL(void (*)(char *, extended_cif *),
-		 /*@out@*/ extended_cif *,
-		 unsigned, unsigned,
-		 /*@out@*/ unsigned *,
-		 void (*fn)());
-/*@=declundef@*/
-/*@=exportheader@*/
+ffi_call_x86(void (*)(char *, extended_cif *), 
+	     /*@out@*/ extended_cif *, 
+	     unsigned, unsigned, 
+	     /*@out@*/ unsigned *, 
+	     void (*fn)());
 #endif
 
 #ifdef _WIN64
@@ -209,17 +194,9 @@ ffi_call(/*@dependent@*/ ffi_cif *cif,
     {
 #if !defined(_WIN64)
     case FFI_SYSV:
-      /*@-usedef@*/
-      return ffi_call_SYSV(ffi_prep_args, &ecif, cif->bytes, 
-			   cif->flags, ecif.rvalue, fn);
-      /*@=usedef@*/
-      break;
-
     case FFI_STDCALL:
-      /*@-usedef@*/
-      return ffi_call_STDCALL(ffi_prep_args, &ecif, cif->bytes,
-			      cif->flags, ecif.rvalue, fn);
-      /*@=usedef@*/
+      return ffi_call_x86(ffi_prep_args, &ecif, cif->bytes, 
+			  cif->flags, ecif.rvalue, fn);
       break;
 #else
     case FFI_SYSV:
diff --git a/Modules/_ctypes/libffi_msvc/win32.S b/Modules/_ctypes/libffi_msvc/win32.S
deleted file mode 100644
index cc82ab9..0000000
--- a/Modules/_ctypes/libffi_msvc/win32.S
+++ /dev/null
@@ -1,243 +0,0 @@
-/* -----------------------------------------------------------------------
-   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.
-   ----------------------------------------------------------------------- */
- 
-#define LIBFFI_ASM
-#include <fficonfig.h>
-#include <ffi.h>
- 
-.text
- 
-.globl ffi_prep_args
- 
-        # This assumes we are using gas.
-        .balign 16
-.globl _ffi_call_SYSV
- 
-_ffi_call_SYSV:
-        pushl %ebp
-        movl  %esp,%ebp
-
-	#THe: save previous %esi, and store the current stack pointer in %esi
-	pushl %esi
-	movl %esp,%esi
-
-        # Make room for all of the new args.
-        movl  16(%ebp),%ecx                                                     
-        subl  %ecx,%esp
- 
-        movl  %esp,%eax
- 
-        # Place all of the ffi_prep_args in position
-        pushl 12(%ebp)
-        pushl %eax
-        call  *8(%ebp)
- 
-        # Return stack to previous state and call the function
-        addl  $8,%esp
- 
-        # FIXME: Align the stack to a 128-bit boundary to avoid
-        # potential performance hits.
-
-	call  *28(%ebp)
- 
-        # Remove the space we pushed for the args
-        movl  16(%ebp),%ecx
-        addl  %ecx,%esp
-
-	sub %esp,%esi # calculate stack pointer difference
-
-        # Load %ecx with the return type code
-        movl  20(%ebp),%ecx
- 
-        # If the return value pointer is NULL, assume no return value.
-        cmpl  $0,24(%ebp)
-        jne   retint
- 
-        # Even if there is no space for the return value, we are
-        # obliged to handle floating-point values.
-        cmpl  $FFI_TYPE_FLOAT,%ecx
-        jne   noretval
-        fstp  %st(0)
- 
-        jmp   epilogue
- 
-retint:
-        cmpl  $FFI_TYPE_INT,%ecx
-        jne   retfloat
-        # Load %ecx with the pointer to storage for the return value
-        movl  24(%ebp),%ecx
-        movl  %eax,0(%ecx)
-        jmp   epilogue
- 
-retfloat:
-        cmpl  $FFI_TYPE_FLOAT,%ecx
-        jne   retdouble   
-         # Load %ecx with the pointer to storage for the return value
-        movl  24(%ebp),%ecx
-        fstps (%ecx)
-        jmp   epilogue
- 
-retdouble:
-        cmpl  $FFI_TYPE_DOUBLE,%ecx
-        jne   retlongdouble
-        # Load %ecx with the pointer to storage for the return value
-        movl  24(%ebp),%ecx
-        fstpl (%ecx)
-        jmp   epilogue
- 
-retlongdouble:
-        cmpl  $FFI_TYPE_LONGDOUBLE,%ecx
-        jne   retint64
-        # Load %ecx with the pointer to storage for the return value
-        movl  24(%ebp),%ecx
-        fstpt (%ecx)
-        jmp   epilogue
- 
-retint64:
-        cmpl  $FFI_TYPE_SINT64,%ecx
-        jne   retstruct
-        # Load %ecx with the pointer to storage for the return value
-        movl  24(%ebp),%ecx
-        movl  %eax,0(%ecx)
-        movl  %edx,4(%ecx)
- 
-retstruct:
-        # Nothing to do!
- 
-noretval:
-epilogue:
-	movl %esi,%eax # return the stack pointer detlta in %eax
-	popl %esi # restore previous %esi
-        movl %ebp,%esp
-        popl %ebp
-        ret
- 
-.ffi_call_SYSV_end:
-
-        # This assumes we are using gas.
-        .balign 16
-.globl _ffi_call_STDCALL
-
-_ffi_call_STDCALL:
-        pushl %ebp
-        movl  %esp,%ebp
-
-	#THe: save previous %esi, and store the current stack pointer in %esi
-	pushl %esi
-	movl %esp,%esi
-	
-        # Make room for all of the new args.
-        movl  16(%ebp),%ecx 
-        subl  %ecx,%esp
-
-        movl  %esp,%eax
-
-        # Place all of the ffi_prep_args in position
-        pushl 12(%ebp)
-        pushl %eax
-        call  *8(%ebp)
-
-        # Return stack to previous state and call the function
-        addl  $8,%esp
-
-        # FIXME: Align the stack to a 128-bit boundary to avoid
-        # potential performance hits.
-
-        call  *28(%ebp)
-
-	sub %esp,%esi # difference in stack
-
-        # stdcall functions pop arguments off the stack themselves
-
-        # Load %ecx with the return type code
-        movl  20(%ebp),%ecx
-
-        # If the return value pointer is NULL, assume no return value.
-        cmpl  $0,24(%ebp)
-        jne   sc_retint
-
-        # Even if there is no space for the return value, we are
-        # obliged to handle floating-point values.
-        cmpl  $FFI_TYPE_FLOAT,%ecx
-        jne   sc_noretval
-        fstp  %st(0)
-
-        jmp   sc_epilogue
-
-sc_retint:
-        cmpl  $FFI_TYPE_INT,%ecx
-        jne   sc_retfloat
-        # Load %ecx with the pointer to storage for the return value
-        movl  24(%ebp),%ecx
-        movl  %eax,0(%ecx)
-        jmp   sc_epilogue
-
-sc_retfloat:
-        cmpl  $FFI_TYPE_FLOAT,%ecx
-        jne   sc_retdouble
-         # Load %ecx with the pointer to storage for the return value
-        movl  24(%ebp),%ecx
-        fstps (%ecx)
-        jmp   sc_epilogue
-
-sc_retdouble:
-        cmpl  $FFI_TYPE_DOUBLE,%ecx
-        jne   sc_retlongdouble
-        # Load %ecx with the pointer to storage for the return value
-        movl  24(%ebp),%ecx
-        fstpl (%ecx)
-        jmp   sc_epilogue
-
-sc_retlongdouble:
-        cmpl  $FFI_TYPE_LONGDOUBLE,%ecx
-        jne   sc_retint64
-        # Load %ecx with the pointer to storage for the return value
-        movl  24(%ebp),%ecx
-        fstpt (%ecx)
-        jmp   sc_epilogue
-
-sc_retint64:
-        cmpl  $FFI_TYPE_SINT64,%ecx
-        jne   sc_retstruct
-        # Load %ecx with the pointer to storage for the return value
-        movl  24(%ebp),%ecx
-        movl  %eax,0(%ecx)
-        movl  %edx,4(%ecx)
-
-sc_retstruct:
-        # Nothing to do!
-
-sc_noretval:
-sc_epilogue:
-        movl %esi,%eax # return the stack difference
-	popl %esi # restore previous %esi value
-        movl %ebp,%esp
-        popl %ebp
-        ret
-
-.ffi_call_STDCALL_end:
diff --git a/Modules/_ctypes/libffi_msvc/win32.c b/Modules/_ctypes/libffi_msvc/win32.c
index 0670c8c..d1149a8 100644
--- a/Modules/_ctypes/libffi_msvc/win32.c
+++ b/Modules/_ctypes/libffi_msvc/win32.c
@@ -29,21 +29,21 @@
 /* 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. */
+/* 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_SYSV(void (* prepfunc)(char *, extended_cif *), /* 8 */
-		 extended_cif *ecif, /* 12 */
-		 unsigned bytes, /* 16 */
-		 unsigned flags, /* 20 */
-		 unsigned *rvalue, /* 24 */
-		 void (*fn)()) /* 28 */
+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
@@ -69,125 +69,20 @@ ffi_call_SYSV(void (* prepfunc)(char *, extended_cif *), /* 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
+// Load ecif->cif->abi
+		mov ecx, [ebp + 12]
+		mov ecx, [ecx]ecif.cif
+		mov ecx, [ecx]ecif.cif.abi
 		
-		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?
+		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