reactos/tools/winebuild/relay.c

   1 /*
   2  * Relay calls helper routines
   3  *
   4  * Copyright 1993 Robert J. Amstadt
   5  * Copyright 1995 Martin von Loewis
   6  * Copyright 1995, 1996, 1997 Alexandre Julliard
   7  * Copyright 1997 Eric Youngdale
   8  * Copyright 1999 Ulrich Weigand
   9  *
  10  * This library is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * This library is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with this library; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23  */
  24
  25 #include "config.h"
  26
  27 #include <ctype.h>
  28
  29 #include "thread.h"
  30 #include "wine/winbase16.h"
  31
  32 #include "build.h"
  33
  34 static void function_header( FILE *outfile, const char *name )
  35 {
  36     fprintf( outfile, "\n\t.align %d\n", get_alignment(4) );
  37     fprintf( outfile, "\t%s\n", func_declaration(name) );
  38     fprintf( outfile, "%s\n", asm_globl(name) );
  39 }
  40
  41
  42 static inline const char *data16_prefix(void)
  43 {
  44     return (target_platform == PLATFORM_SVR4) ? "\tdata16\n" : "";
  45 }
  46
  47 /*******************************************************************
  48  *         BuildCallFrom16Core
  49  *
  50  * This routine builds the core routines used in 16->32 thunks:
  51  * CallFrom16Word, CallFrom16Long, CallFrom16Register, and CallFrom16Thunk.
  52  *
  53  * These routines are intended to be called via a far call (with 32-bit
  54  * operand size) from 16-bit code.  The 16-bit code stub must push %bp,
  55  * the 32-bit entry point to be called, and the argument conversion
  56  * routine to be used (see stack layout below).
  57  *
  58  * The core routine completes the STACK16FRAME on the 16-bit stack and
  59  * switches to the 32-bit stack.  Then, the argument conversion routine
  60  * is called; it gets passed the 32-bit entry point and a pointer to the
  61  * 16-bit arguments (on the 16-bit stack) as parameters. (You can either
  62  * use conversion routines automatically generated by BuildCallFrom16,
  63  * or write your own for special purposes.)
  64  *
  65  * The conversion routine must call the 32-bit entry point, passing it
  66  * the converted arguments, and return its return value to the core.
  67  * After the conversion routine has returned, the core switches back
  68  * to the 16-bit stack, converts the return value to the DX:AX format
  69  * (CallFrom16Long), and returns to the 16-bit call stub.  All parameters,
  70  * including %bp, are popped off the stack.
  71  *
  72  * The 16-bit call stub now returns to the caller, popping the 16-bit
  73  * arguments if necessary (pascal calling convention).
  74  *
  75  * In the case of a 'register' function, CallFrom16Register fills a
  76  * CONTEXT86 structure with the values all registers had at the point
  77  * the first instruction of the 16-bit call stub was about to be
  78  * executed.  A pointer to this CONTEXT86 is passed as third parameter
  79  * to the argument conversion routine, which typically passes it on
  80  * to the called 32-bit entry point.
  81  *
  82  * CallFrom16Thunk is a special variant used by the implementation of
  83  * the Win95 16->32 thunk functions C16ThkSL and C16ThkSL01 and is
  84  * implemented as follows:
  85  * On entry, the EBX register is set up to contain a flat pointer to the
  86  * 16-bit stack such that EBX+22 points to the first argument.
  87  * Then, the entry point is called, while EBP is set up to point
  88  * to the return address (on the 32-bit stack).
  89  * The called function returns with CX set to the number of bytes
  90  * to be popped of the caller's stack.
  91  *
  92  * Stack layout upon entry to the core routine (STACK16FRAME):
  93  *  ...           ...
  94  * (sp+24) word   first 16-bit arg
  95  * (sp+22) word   cs
  96  * (sp+20) word   ip
  97  * (sp+18) word   bp
  98  * (sp+14) long   32-bit entry point (reused for Win16 mutex recursion count)
  99  * (sp+12) word   ip of actual entry point (necessary for relay debugging)
 100  * (sp+8)  long   relay (argument conversion) function entry point
 101  * (sp+4)  long   cs of 16-bit entry point
 102  * (sp)    long   ip of 16-bit entry point
 103  *
 104  * Added on the stack:
 105  * (sp-2)  word   saved gs
 106  * (sp-4)  word   saved fs
 107  * (sp-6)  word   saved es
 108  * (sp-8)  word   saved ds
 109  * (sp-12) long   saved ebp
 110  * (sp-16) long   saved ecx
 111  * (sp-20) long   saved edx
 112  * (sp-24) long   saved previous stack
 113  */
 114 static void BuildCallFrom16Core( FILE *outfile, int reg_func, int thunk )
 115 {
 116     /* Function header */
 117     if (thunk) function_header( outfile, "__wine_call_from_16_thunk" );
 118     else if (reg_func) function_header( outfile, "__wine_call_from_16_regs" );
 119     else function_header( outfile, "__wine_call_from_16" );
 120
 121     /* Create STACK16FRAME (except STACK32FRAME link) */
 122     fprintf( outfile, "\tpushw %%gs\n" );
 123     fprintf( outfile, "\tpushw %%fs\n" );
 124     fprintf( outfile, "\tpushw %%es\n" );
 125     fprintf( outfile, "\tpushw %%ds\n" );
 126     fprintf( outfile, "\tpushl %%ebp\n" );
 127     fprintf( outfile, "\tpushl %%ecx\n" );
 128     fprintf( outfile, "\tpushl %%edx\n" );
 129
 130     /* Save original EFlags register */
 131     if (reg_func) fprintf( outfile, "\tpushfl\n" );
 132
 133     if ( UsePIC )
 134     {
 135         fprintf( outfile, "\tcall 1f\n" );
 136         fprintf( outfile, "1:\tpopl %%ecx\n" );
 137         fprintf( outfile, "\t.byte 0x2e\n\tmovl %s-1b(%%ecx),%%edx\n",
 138                  asm_name("CallTo16_DataSelector") );
 139     }
 140     else
 141         fprintf( outfile, "\t.byte 0x2e\n\tmovl %s,%%edx\n", asm_name("CallTo16_DataSelector") );
 142
 143     /* Load 32-bit segment registers */
 144     fprintf( outfile, "%s\tmovw %%dx, %%ds\n", data16_prefix() );
 145     fprintf( outfile, "%s\tmovw %%dx, %%es\n", data16_prefix() );
 146
 147     if ( UsePIC )
 148         fprintf( outfile, "\tmovw %s-1b(%%ecx), %%fs\n", asm_name("CallTo16_TebSelector") );
 149     else
 150         fprintf( outfile, "\tmovw %s, %%fs\n", asm_name("CallTo16_TebSelector") );
 151
 152     fprintf( outfile, "\t.byte 0x64\n\tmov (%d),%%gs\n", STRUCTOFFSET(TEB,gs_sel) );
 153
 154     /* Translate STACK16FRAME base to flat offset in %edx */
 155     fprintf( outfile, "\tmovw %%ss, %%dx\n" );
 156     fprintf( outfile, "\tandl $0xfff8, %%edx\n" );
 157     fprintf( outfile, "\tshrl $1, %%edx\n" );
 158     if (UsePIC)
 159     {
 160         fprintf( outfile, "\taddl wine_ldt_copy_ptr-1b(%%ecx),%%edx\n" );
 161         fprintf( outfile, "\tmovl (%%edx), %%edx\n" );
 162     }
 163     else
 164         fprintf( outfile, "\tmovl %s(%%edx), %%edx\n", asm_name("wine_ldt_copy") );
 165     fprintf( outfile, "\tmovzwl %%sp, %%ebp\n" );
 166     fprintf( outfile, "\tleal %d(%%ebp,%%edx), %%edx\n", reg_func ? 0 : -4 );
 167
 168     /* Get saved flags into %ecx */
 169     if (reg_func) fprintf( outfile, "\tpopl %%ecx\n" );
 170
 171     /* Get the 32-bit stack pointer from the TEB and complete STACK16FRAME */
 172     fprintf( outfile, "\t.byte 0x64\n\tmovl (%d), %%ebp\n", STACKOFFSET );
 173     fprintf( outfile, "\tpushl %%ebp\n" );
 174
 175     /* Switch stacks */
 176     fprintf( outfile, "%s\t.byte 0x64\n\tmovw %%ss, (%d)\n", data16_prefix(), STACKOFFSET + 2 );
 177     fprintf( outfile, "\t.byte 0x64\n\tmovw %%sp, (%d)\n", STACKOFFSET );
 178     fprintf( outfile, "\tpushl %%ds\n" );
 179     fprintf( outfile, "\tpopl %%ss\n" );
 180     fprintf( outfile, "\tmovl %%ebp, %%esp\n" );
 181     fprintf( outfile, "\taddl $%d, %%ebp\n", STRUCTOFFSET(STACK32FRAME, ebp) );
 182
 183
 184     /* At this point:
 185        STACK16FRAME is completely set up
 186        DS, ES, SS: flat data segment
 187        FS: current TEB
 188        ESP: points to last STACK32FRAME
 189        EBP: points to ebp member of last STACK32FRAME
 190        EDX: points to current STACK16FRAME
 191        ECX: contains saved flags
 192        all other registers: unchanged */
 193
 194     /* Special case: C16ThkSL stub */
 195     if ( thunk )
 196     {
 197         /* Set up registers as expected and call thunk */
 198         fprintf( outfile, "\tleal %d(%%edx), %%ebx\n", sizeof(STACK16FRAME)-22 );
 199         fprintf( outfile, "\tleal -4(%%esp), %%ebp\n" );
 200
 201         fprintf( outfile, "\tcall *%d(%%edx)\n", STACK16OFFSET(entry_point) );
 202
 203         /* Switch stack back */
 204         fprintf( outfile, "\t.byte 0x64\n\tmovw (%d), %%ss\n", STACKOFFSET+2 );
 205         fprintf( outfile, "\t.byte 0x64\n\tmovzwl (%d), %%esp\n", STACKOFFSET );
 206         fprintf( outfile, "\t.byte 0x64\n\tpopl (%d)\n", STACKOFFSET );
 207
 208         /* Restore registers and return directly to caller */
 209         fprintf( outfile, "\taddl $8, %%esp\n" );
 210         fprintf( outfile, "\tpopl %%ebp\n" );
 211         fprintf( outfile, "\tpopw %%ds\n" );
 212         fprintf( outfile, "\tpopw %%es\n" );
 213         fprintf( outfile, "\tpopw %%fs\n" );
 214         fprintf( outfile, "\tpopw %%gs\n" );
 215         fprintf( outfile, "\taddl $20, %%esp\n" );
 216
 217         fprintf( outfile, "\txorb %%ch, %%ch\n" );
 218         fprintf( outfile, "\tpopl %%ebx\n" );
 219         fprintf( outfile, "\taddw %%cx, %%sp\n" );
 220         fprintf( outfile, "\tpush %%ebx\n" );
 221
 222         fprintf( outfile, "\t.byte 0x66\n" );
 223         fprintf( outfile, "\tlret\n" );
 224
 225         return;
 226     }
 227
 228
 229     /* Build register CONTEXT */
 230     if ( reg_func )
 231     {
 232         fprintf( outfile, "\tsubl $%d, %%esp\n", sizeof(CONTEXT86) );
 233
 234         fprintf( outfile, "\tmovl %%ecx, %d(%%esp)\n", CONTEXTOFFSET(EFlags) );
 235
 236         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(Eax) );
 237         fprintf( outfile, "\tmovl %%ebx, %d(%%esp)\n", CONTEXTOFFSET(Ebx) );
 238         fprintf( outfile, "\tmovl %%esi, %d(%%esp)\n", CONTEXTOFFSET(Esi) );
 239         fprintf( outfile, "\tmovl %%edi, %d(%%esp)\n", CONTEXTOFFSET(Edi) );
 240
 241         fprintf( outfile, "\tmovl %d(%%edx), %%eax\n", STACK16OFFSET(ebp) );
 242         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(Ebp) );
 243         fprintf( outfile, "\tmovl %d(%%edx), %%eax\n", STACK16OFFSET(ecx) );
 244         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(Ecx) );
 245         fprintf( outfile, "\tmovl %d(%%edx), %%eax\n", STACK16OFFSET(edx) );
 246         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(Edx) );
 247
 248         fprintf( outfile, "\tmovzwl %d(%%edx), %%eax\n", STACK16OFFSET(ds) );
 249         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(SegDs) );
 250         fprintf( outfile, "\tmovzwl %d(%%edx), %%eax\n", STACK16OFFSET(es) );
 251         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(SegEs) );
 252         fprintf( outfile, "\tmovzwl %d(%%edx), %%eax\n", STACK16OFFSET(fs) );
 253         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(SegFs) );
 254         fprintf( outfile, "\tmovzwl %d(%%edx), %%eax\n", STACK16OFFSET(gs) );
 255         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(SegGs) );
 256
 257         fprintf( outfile, "\tmovzwl %d(%%edx), %%eax\n", STACK16OFFSET(cs) );
 258         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(SegCs) );
 259         fprintf( outfile, "\tmovzwl %d(%%edx), %%eax\n", STACK16OFFSET(ip) );
 260         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(Eip) );
 261
 262         fprintf( outfile, "\t.byte 0x64\n\tmovzwl (%d), %%eax\n", STACKOFFSET+2 );
 263         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(SegSs) );
 264         fprintf( outfile, "\t.byte 0x64\n\tmovzwl (%d), %%eax\n", STACKOFFSET );
 265         fprintf( outfile, "\taddl $%d, %%eax\n", STACK16OFFSET(ip) );
 266         fprintf( outfile, "\tmovl %%eax, %d(%%esp)\n", CONTEXTOFFSET(Esp) );
 267 #if 0
 268         fprintf( outfile, "\tfsave %d(%%esp)\n", CONTEXTOFFSET(FloatSave) );
 269 #endif
 270
 271         /* Push address of CONTEXT86 structure -- popped by the relay routine */
 272         fprintf( outfile, "\tmovl %%esp,%%eax\n" );
 273         fprintf( outfile, "\tandl $~15,%%esp\n" );
 274         fprintf( outfile, "\tsubl $4,%%esp\n" );
 275         fprintf( outfile, "\tpushl %%eax\n" );
 276     }
 277     else
 278     {
 279         fprintf( outfile, "\tsubl $8,%%esp\n" );
 280         fprintf( outfile, "\tandl $~15,%%esp\n" );
 281         fprintf( outfile, "\taddl $8,%%esp\n" );
 282     }
 283
 284     /* Call relay routine (which will call the API entry point) */
 285     fprintf( outfile, "\tleal %d(%%edx), %%eax\n", sizeof(STACK16FRAME) );
 286     fprintf( outfile, "\tpushl %%eax\n" );
 287     fprintf( outfile, "\tpushl %d(%%edx)\n", STACK16OFFSET(entry_point) );
 288     fprintf( outfile, "\tcall *%d(%%edx)\n", STACK16OFFSET(relay) );
 289
 290     if ( reg_func )
 291     {
 292         fprintf( outfile, "\tleal -%d(%%ebp), %%ebx\n",
 293                  sizeof(CONTEXT) + STRUCTOFFSET(STACK32FRAME, ebp) );
 294
 295         /* Switch stack back */
 296         fprintf( outfile, "\t.byte 0x64\n\tmovw (%d), %%ss\n", STACKOFFSET+2 );
 297         fprintf( outfile, "\t.byte 0x64\n\tmovzwl (%d), %%esp\n", STACKOFFSET );
 298         fprintf( outfile, "\t.byte 0x64\n\tpopl (%d)\n", STACKOFFSET );
 299
 300         /* Get return address to CallFrom16 stub */
 301         fprintf( outfile, "\taddw $%d, %%sp\n", STACK16OFFSET(callfrom_ip)-4 );
 302         fprintf( outfile, "\tpopl %%eax\n" );
 303         fprintf( outfile, "\tpopl %%edx\n" );
 304
 305         /* Restore all registers from CONTEXT */
 306         fprintf( outfile, "\tmovw %d(%%ebx), %%ss\n", CONTEXTOFFSET(SegSs) );
 307         fprintf( outfile, "\tmovl %d(%%ebx), %%esp\n", CONTEXTOFFSET(Esp) );
 308         fprintf( outfile, "\taddl $4, %%esp\n" );  /* room for final return address */
 309
 310         fprintf( outfile, "\tpushw %d(%%ebx)\n", CONTEXTOFFSET(SegCs) );
 311         fprintf( outfile, "\tpushw %d(%%ebx)\n", CONTEXTOFFSET(Eip) );
 312         fprintf( outfile, "\tpushl %%edx\n" );
 313         fprintf( outfile, "\tpushl %%eax\n" );
 314         fprintf( outfile, "\tpushl %d(%%ebx)\n", CONTEXTOFFSET(EFlags) );
 315         fprintf( outfile, "\tpushl %d(%%ebx)\n", CONTEXTOFFSET(SegDs) );
 316
 317         fprintf( outfile, "\tpushl %d(%%ebx)\n", CONTEXTOFFSET(SegEs) );
 318         fprintf( outfile, "\tpopl %%es\n" );
 319         fprintf( outfile, "\tpushl %d(%%ebx)\n", CONTEXTOFFSET(SegFs) );
 320         fprintf( outfile, "\tpopl %%fs\n" );
 321         fprintf( outfile, "\tpushl %d(%%ebx)\n", CONTEXTOFFSET(SegGs) );
 322         fprintf( outfile, "\tpopl %%gs\n" );
 323
 324         fprintf( outfile, "\tmovl %d(%%ebx), %%ebp\n", CONTEXTOFFSET(Ebp) );
 325         fprintf( outfile, "\tmovl %d(%%ebx), %%esi\n", CONTEXTOFFSET(Esi) );
 326         fprintf( outfile, "\tmovl %d(%%ebx), %%edi\n", CONTEXTOFFSET(Edi) );
 327         fprintf( outfile, "\tmovl %d(%%ebx), %%eax\n", CONTEXTOFFSET(Eax) );
 328         fprintf( outfile, "\tmovl %d(%%ebx), %%edx\n", CONTEXTOFFSET(Edx) );
 329         fprintf( outfile, "\tmovl %d(%%ebx), %%ecx\n", CONTEXTOFFSET(Ecx) );
 330         fprintf( outfile, "\tmovl %d(%%ebx), %%ebx\n", CONTEXTOFFSET(Ebx) );
 331
 332         fprintf( outfile, "\tpopl %%ds\n" );
 333         fprintf( outfile, "\tpopfl\n" );
 334         fprintf( outfile, "\tlret\n" );
 335     }
 336     else
 337     {
 338         /* Switch stack back */
 339         fprintf( outfile, "\t.byte 0x64\n\tmovw (%d), %%ss\n", STACKOFFSET+2 );
 340         fprintf( outfile, "\t.byte 0x64\n\tmovzwl (%d), %%esp\n", STACKOFFSET );
 341         fprintf( outfile, "\t.byte 0x64\n\tpopl (%d)\n", STACKOFFSET );
 342
 343         /* Restore registers */
 344         fprintf( outfile, "\tpopl %%edx\n" );
 345         fprintf( outfile, "\tpopl %%ecx\n" );
 346         fprintf( outfile, "\tpopl %%ebp\n" );
 347         fprintf( outfile, "\tpopw %%ds\n" );
 348         fprintf( outfile, "\tpopw %%es\n" );
 349         fprintf( outfile, "\tpopw %%fs\n" );
 350         fprintf( outfile, "\tpopw %%gs\n" );
 351
 352         /* Return to return stub which will return to caller */
 353         fprintf( outfile, "\tlret $12\n" );
 354     }
 355     if (thunk) output_function_size( outfile, "__wine_call_from_16_thunk" );
 356     else if (reg_func) output_function_size( outfile, "__wine_call_from_16_regs" );
 357     else output_function_size( outfile, "__wine_call_from_16" );
 358 }
 359
 360
 361 /*******************************************************************
 362  *         BuildCallTo16Core
 363  *
 364  * This routine builds the core routines used in 32->16 thunks:
 365  *
 366  * extern DWORD WINAPI wine_call_to_16( FARPROC16 target, DWORD cbArgs, PEXCEPTION_HANDLER handler );
 367  * extern void WINAPI wine_call_to_16_regs( CONTEXT86 *context, DWORD cbArgs, PEXCEPTION_HANDLER handler );
 368  *
 369  * These routines can be called directly from 32-bit code.
 370  *
 371  * All routines expect that the 16-bit stack contents (arguments) and the
 372  * return address (segptr to CallTo16_Ret) were already set up by the
 373  * caller; nb_args must contain the number of bytes to be conserved.  The
 374  * 16-bit SS:SP will be set accordinly.
 375  *
 376  * All other registers are either taken from the CONTEXT86 structure
 377  * or else set to default values.  The target routine address is either
 378  * given directly or taken from the CONTEXT86.
 379  */
 380 static void BuildCallTo16Core( FILE *outfile, int reg_func )
 381 {
 382     const char *name = reg_func ? "wine_call_to_16_regs" : "wine_call_to_16";
 383
 384     /* Function header */
 385     function_header( outfile, name );
 386
 387     /* Function entry sequence */
 388     fprintf( outfile, "\tpushl %%ebp\n" );
 389     fprintf( outfile, "\tmovl %%esp, %%ebp\n" );
 390
 391     /* Save the 32-bit registers */
 392     fprintf( outfile, "\tpushl %%ebx\n" );
 393     fprintf( outfile, "\tpushl %%esi\n" );
 394     fprintf( outfile, "\tpushl %%edi\n" );
 395     fprintf( outfile, "\t.byte 0x64\n\tmov %%gs,(%d)\n", STRUCTOFFSET(TEB,gs_sel) );
 396
 397     /* Setup exception frame */
 398     fprintf( outfile, "\t.byte 0x64\n\tpushl (%d)\n", STACKOFFSET );
 399     fprintf( outfile, "\tpushl 16(%%ebp)\n" ); /* handler */
 400     fprintf( outfile, "\t.byte 0x64\n\tpushl (%d)\n", STRUCTOFFSET(TEB,Tib.ExceptionList) );
 401     fprintf( outfile, "\t.byte 0x64\n\tmovl %%esp,(%d)\n", STRUCTOFFSET(TEB,Tib.ExceptionList) );
 402
 403     /* Call the actual CallTo16 routine (simulate a lcall) */
 404     fprintf( outfile, "\tpushl %%cs\n" );
 405     fprintf( outfile, "\tcall .L%s\n", name );
 406
 407     /* Remove exception frame */
 408     fprintf( outfile, "\t.byte 0x64\n\tpopl (%d)\n", STRUCTOFFSET(TEB,Tib.ExceptionList) );
 409     fprintf( outfile, "\taddl $4, %%esp\n" );
 410     fprintf( outfile, "\t.byte 0x64\n\tpopl (%d)\n", STACKOFFSET );
 411
 412     if ( !reg_func )
 413     {
 414         /* Convert return value */
 415         fprintf( outfile, "\tandl $0xffff,%%eax\n" );
 416         fprintf( outfile, "\tshll $16,%%edx\n" );
 417         fprintf( outfile, "\torl %%edx,%%eax\n" );
 418     }
 419     else
 420     {
 421         /*
 422          * Modify CONTEXT86 structure to contain new values
 423          *
 424          * NOTE:  We restore only EAX, EBX, EDX, EDX, EBP, and ESP.
 425          *        The segment registers as well as ESI and EDI should
 426          *        not be modified by a well-behaved 16-bit routine in
 427          *        any case.  [If necessary, we could restore them as well,
 428          *        at the cost of a somewhat less efficient return path.]
 429          */
 430
 431         fprintf( outfile, "\tmovl %d(%%esp), %%edi\n", STACK32OFFSET(target) - STACK32OFFSET(edi));
 432                 /* everything above edi has been popped already */
 433
 434         fprintf( outfile, "\tmovl %%eax, %d(%%edi)\n", CONTEXTOFFSET(Eax) );
 435         fprintf( outfile, "\tmovl %%ebx, %d(%%edi)\n", CONTEXTOFFSET(Ebx) );
 436         fprintf( outfile, "\tmovl %%ecx, %d(%%edi)\n", CONTEXTOFFSET(Ecx) );
 437         fprintf( outfile, "\tmovl %%edx, %d(%%edi)\n", CONTEXTOFFSET(Edx) );
 438         fprintf( outfile, "\tmovl %%ebp, %d(%%edi)\n", CONTEXTOFFSET(Ebp) );
 439         fprintf( outfile, "\tmovl %%esi, %d(%%edi)\n", CONTEXTOFFSET(Esp) );
 440                  /* The return glue code saved %esp into %esi */
 441     }
 442
 443     /* Restore the 32-bit registers */
 444     fprintf( outfile, "\tpopl %%edi\n" );
 445     fprintf( outfile, "\tpopl %%esi\n" );
 446     fprintf( outfile, "\tpopl %%ebx\n" );
 447
 448     /* Function exit sequence */
 449     fprintf( outfile, "\tpopl %%ebp\n" );
 450     fprintf( outfile, "\tret $12\n" );
 451
 452
 453     /* Start of the actual CallTo16 routine */
 454
 455     fprintf( outfile, ".L%s:\n", name );
 456
 457     /* Switch to the 16-bit stack */
 458     fprintf( outfile, "\tmovl %%esp,%%edx\n" );
 459     fprintf( outfile, "%s\t.byte 0x64\n\tmovw (%d),%%ss\n", data16_prefix(), STACKOFFSET + 2);
 460     fprintf( outfile, "\t.byte 0x64\n\tmovw (%d),%%sp\n", STACKOFFSET );
 461     fprintf( outfile, "\t.byte 0x64\n\tmovl %%edx,(%d)\n", STACKOFFSET );
 462
 463     /* Make %bp point to the previous stackframe (built by CallFrom16) */
 464     fprintf( outfile, "\tmovzwl %%sp,%%ebp\n" );
 465     fprintf( outfile, "\tleal %d(%%ebp),%%ebp\n", STACK16OFFSET(bp) );
 466
 467     /* Add the specified offset to the new sp */
 468     fprintf( outfile, "\tsubw %d(%%edx), %%sp\n", STACK32OFFSET(nb_args) );
 469
 470     if (reg_func)
 471     {
 472         /* Push the called routine address */
 473         fprintf( outfile, "\tmovl %d(%%edx),%%edx\n", STACK32OFFSET(target) );
 474         fprintf( outfile, "\tpushw %d(%%edx)\n", CONTEXTOFFSET(SegCs) );
 475         fprintf( outfile, "\tpushw %d(%%edx)\n", CONTEXTOFFSET(Eip) );
 476
 477         /* Get the registers */
 478         fprintf( outfile, "\tpushw %d(%%edx)\n", CONTEXTOFFSET(SegDs) );
 479         fprintf( outfile, "\tpushl %d(%%edx)\n", CONTEXTOFFSET(SegEs) );
 480         fprintf( outfile, "\tpopl %%es\n" );
 481         fprintf( outfile, "\tpushl %d(%%edx)\n", CONTEXTOFFSET(SegFs) );
 482         fprintf( outfile, "\tpopl %%fs\n" );
 483         fprintf( outfile, "\tpushl %d(%%edx)\n", CONTEXTOFFSET(SegGs) );
 484         fprintf( outfile, "\tpopl %%gs\n" );
 485         fprintf( outfile, "\tmovl %d(%%edx),%%ebp\n", CONTEXTOFFSET(Ebp) );
 486         fprintf( outfile, "\tmovl %d(%%edx),%%esi\n", CONTEXTOFFSET(Esi) );
 487         fprintf( outfile, "\tmovl %d(%%edx),%%edi\n", CONTEXTOFFSET(Edi) );
 488         fprintf( outfile, "\tmovl %d(%%edx),%%eax\n", CONTEXTOFFSET(Eax) );
 489         fprintf( outfile, "\tmovl %d(%%edx),%%ebx\n", CONTEXTOFFSET(Ebx) );
 490         fprintf( outfile, "\tmovl %d(%%edx),%%ecx\n", CONTEXTOFFSET(Ecx) );
 491         fprintf( outfile, "\tmovl %d(%%edx),%%edx\n", CONTEXTOFFSET(Edx) );
 492
 493         /* Get the 16-bit ds */
 494         fprintf( outfile, "\tpopw %%ds\n" );
 495     }
 496     else  /* not a register function */
 497     {
 498         /* Push the called routine address */
 499         fprintf( outfile, "\tpushl %d(%%edx)\n", STACK32OFFSET(target) );
 500
 501         /* Set %fs and %gs to the value saved by the last CallFrom16 */
 502         fprintf( outfile, "\tpushw %d(%%ebp)\n", STACK16OFFSET(fs)-STACK16OFFSET(bp) );
 503         fprintf( outfile, "\tpopw %%fs\n" );
 504         fprintf( outfile, "\tpushw %d(%%ebp)\n", STACK16OFFSET(gs)-STACK16OFFSET(bp) );
 505         fprintf( outfile, "\tpopw %%gs\n" );
 506
 507         /* Set %ds and %es (and %ax just in case) equal to %ss */
 508         fprintf( outfile, "\tmovw %%ss,%%ax\n" );
 509         fprintf( outfile, "\tmovw %%ax,%%ds\n" );
 510         fprintf( outfile, "\tmovw %%ax,%%es\n" );
 511     }
 512
 513     /* Jump to the called routine */
 514     fprintf( outfile, "\t.byte 0x66\n" );
 515     fprintf( outfile, "\tlret\n" );
 516
 517     /* Function footer */
 518     output_function_size( outfile, name );
 519 }
 520
 521
 522 /*******************************************************************
 523  *         BuildRet16Func
 524  *
 525  * Build the return code for 16-bit callbacks
 526  */
 527 static void BuildRet16Func( FILE *outfile )
 528 {
 529     function_header( outfile, "__wine_call_to_16_ret" );
 530
 531     /* Save %esp into %esi */
 532     fprintf( outfile, "\tmovl %%esp,%%esi\n" );
 533
 534     /* Restore 32-bit segment registers */
 535
 536     fprintf( outfile, "\t.byte 0x2e\n\tmovl %s", asm_name("CallTo16_DataSelector") );
 537     fprintf( outfile, "-%s,%%edi\n", asm_name("__wine_call16_start") );
 538     fprintf( outfile, "%s\tmovw %%di,%%ds\n", data16_prefix() );
 539     fprintf( outfile, "%s\tmovw %%di,%%es\n", data16_prefix() );
 540
 541     fprintf( outfile, "\t.byte 0x2e\n\tmov %s", asm_name("CallTo16_TebSelector") );
 542     fprintf( outfile, "-%s,%%fs\n", asm_name("__wine_call16_start") );
 543
 544     fprintf( outfile, "\t.byte 0x64\n\tmov (%d),%%gs\n", STRUCTOFFSET(TEB,gs_sel) );
 545
 546     /* Restore the 32-bit stack */
 547
 548     fprintf( outfile, "%s\tmovw %%di,%%ss\n", data16_prefix() );
 549     fprintf( outfile, "\t.byte 0x64\n\tmovl (%d),%%esp\n", STACKOFFSET );
 550
 551     /* Return to caller */
 552
 553     fprintf( outfile, "\tlret\n" );
 554     output_function_size( outfile, "__wine_call_to_16_ret" );
 555 }
 556
 557
 558 /*******************************************************************
 559  *         BuildCallTo32CBClient
 560  *
 561  * Call a CBClient relay stub from 32-bit code (KERNEL.620).
 562  *
 563  * Since the relay stub is itself 32-bit, this should not be a problem;
 564  * unfortunately, the relay stubs are expected to switch back to a
 565  * 16-bit stack (and 16-bit code) after completion :-(
 566  *
 567  * This would conflict with our 16- vs. 32-bit stack handling, so
 568  * we simply switch *back* to our 32-bit stack before returning to
 569  * the caller ...
 570  *
 571  * The CBClient relay stub expects to be called with the following
 572  * 16-bit stack layout, and with ebp and ebx pointing into the 16-bit
 573  * stack at the designated places:
 574  *
 575  *    ...
 576  *  (ebp+14) original arguments to the callback routine
 577  *  (ebp+10) far return address to original caller
 578  *  (ebp+6)  Thunklet target address
 579  *  (ebp+2)  Thunklet relay ID code
 580  *  (ebp)    BP (saved by CBClientGlueSL)
 581  *  (ebp-2)  SI (saved by CBClientGlueSL)
 582  *  (ebp-4)  DI (saved by CBClientGlueSL)
 583  *  (ebp-6)  DS (saved by CBClientGlueSL)
 584  *
 585  *   ...     buffer space used by the 16-bit side glue for temp copies
 586  *
 587  *  (ebx+4)  far return address to 16-bit side glue code
 588  *  (ebx)    saved 16-bit ss:sp (pointing to ebx+4)
 589  *
 590  * The 32-bit side glue code accesses both the original arguments (via ebp)
 591  * and the temporary copies prepared by the 16-bit side glue (via ebx).
 592  * After completion, the stub will load ss:sp from the buffer at ebx
 593  * and perform a far return to 16-bit code.
 594  *
 595  * To trick the relay stub into returning to us, we replace the 16-bit
 596  * return address to the glue code by a cs:ip pair pointing to our
 597  * return entry point (the original return address is saved first).
 598  * Our return stub thus called will then reload the 32-bit ss:esp and
 599  * return to 32-bit code (by using and ss:esp value that we have also
 600  * pushed onto the 16-bit stack before and a cs:eip values found at
 601  * that position on the 32-bit stack).  The ss:esp to be restored is
 602  * found relative to the 16-bit stack pointer at:
 603  *
 604  *  (ebx-4)   ss  (flat)
 605  *  (ebx-8)   sp  (32-bit stack pointer)
 606  *
 607  * The second variant of this routine, CALL32_CBClientEx, which is used
 608  * to implement KERNEL.621, has to cope with yet another problem: Here,
 609  * the 32-bit side directly returns to the caller of the CBClient thunklet,
 610  * restoring registers saved by CBClientGlueSL and cleaning up the stack.
 611  * As we have to return to our 32-bit code first, we have to adapt the
 612  * layout of our temporary area so as to include values for the registers
 613  * that are to be restored, and later (in the implementation of KERNEL.621)
 614  * we *really* restore them. The return stub restores DS, DI, SI, and BP
 615  * from the stack, skips the next 8 bytes (CBClient relay code / target),
 616  * and then performs a lret NN, where NN is the number of arguments to be
 617  * removed. Thus, we prepare our temporary area as follows:
 618  *
 619  *     (ebx+22) 16-bit cs  (this segment)
 620  *     (ebx+20) 16-bit ip  ('16-bit' return entry point)
 621  *     (ebx+16) 32-bit ss  (flat)
 622  *     (ebx+12) 32-bit sp  (32-bit stack pointer)
 623  *     (ebx+10) 16-bit bp  (points to ebx+24)
 624  *     (ebx+8)  16-bit si  (ignored)
 625  *     (ebx+6)  16-bit di  (ignored)
 626  *     (ebx+4)  16-bit ds  (we actually use the flat DS here)
 627  *     (ebx+2)  16-bit ss  (16-bit stack segment)
 628  *     (ebx+0)  16-bit sp  (points to ebx+4)
 629  *
 630  * Note that we ensure that DS is not changed and remains the flat segment,
 631  * and the 32-bit stack pointer our own return stub needs fits just
 632  * perfectly into the 8 bytes that are skipped by the Windows stub.
 633  * One problem is that we have to determine the number of removed arguments,
 634  * as these have to be really removed in KERNEL.621. Thus, the BP value
 635  * that we place in the temporary area to be restored, contains the value
 636  * that SP would have if no arguments were removed. By comparing the actual
 637  * value of SP with this value in our return stub we can compute the number
 638  * of removed arguments. This is then returned to KERNEL.621.
 639  *
 640  * The stack layout of this function:
 641  * (ebp+20)  nArgs     pointer to variable receiving nr. of args (Ex only)
 642  * (ebp+16)  esi       pointer to caller's esi value
 643  * (ebp+12)  arg       ebp value to be set for relay stub
 644  * (ebp+8)   func      CBClient relay stub address
 645  * (ebp+4)   ret addr
 646  * (ebp)     ebp
 647  */
 648 static void BuildCallTo32CBClient( FILE *outfile, BOOL isEx )
 649 {
 650     function_header( outfile, isEx ? "CALL32_CBClientEx" : "CALL32_CBClient" );
 651
 652     /* Entry code */
 653
 654     fprintf( outfile, "\tpushl %%ebp\n" );
 655     fprintf( outfile, "\tmovl %%esp,%%ebp\n" );
 656     fprintf( outfile, "\tpushl %%edi\n" );
 657     fprintf( outfile, "\tpushl %%esi\n" );
 658     fprintf( outfile, "\tpushl %%ebx\n" );
 659
 660     /* Get pointer to temporary area and save the 32-bit stack pointer */
 661
 662     fprintf( outfile, "\tmovl 16(%%ebp), %%ebx\n" );
 663     fprintf( outfile, "\tleal -8(%%esp), %%eax\n" );
 664
 665     if ( !isEx )
 666         fprintf( outfile, "\tmovl %%eax, -8(%%ebx)\n" );
 667     else
 668         fprintf( outfile, "\tmovl %%eax, 12(%%ebx)\n" );
 669
 670     /* Set up registers and call CBClient relay stub (simulating a far call) */
 671
 672     fprintf( outfile, "\tmovl 20(%%ebp), %%esi\n" );
 673     fprintf( outfile, "\tmovl (%%esi), %%esi\n" );
 674
 675     fprintf( outfile, "\tmovl 8(%%ebp), %%eax\n" );
 676     fprintf( outfile, "\tmovl 12(%%ebp), %%ebp\n" );
 677
 678     fprintf( outfile, "\tpushl %%cs\n" );
 679     fprintf( outfile, "\tcall *%%eax\n" );
 680
 681     /* Return new esi value to caller */
 682
 683     fprintf( outfile, "\tmovl 32(%%esp), %%edi\n" );
 684     fprintf( outfile, "\tmovl %%esi, (%%edi)\n" );
 685
 686     /* Return argument size to caller */
 687     if ( isEx )
 688     {
 689         fprintf( outfile, "\tmovl 36(%%esp), %%ebx\n" );
 690         fprintf( outfile, "\tmovl %%ebp, (%%ebx)\n" );
 691     }
 692
 693     /* Restore registers and return */
 694
 695     fprintf( outfile, "\tpopl %%ebx\n" );
 696     fprintf( outfile, "\tpopl %%esi\n" );
 697     fprintf( outfile, "\tpopl %%edi\n" );
 698     fprintf( outfile, "\tpopl %%ebp\n" );
 699     fprintf( outfile, "\tret\n" );
 700     output_function_size( outfile, isEx ? "CALL32_CBClientEx" : "CALL32_CBClient" );
 701
 702     /* '16-bit' return stub */
 703
 704     function_header( outfile, isEx ? "CALL32_CBClientEx_Ret" : "CALL32_CBClient_Ret" );
 705     if ( !isEx )
 706     {
 707         fprintf( outfile, "\tmovzwl %%sp, %%ebx\n" );
 708         fprintf( outfile, "\tlssl %%ss:-16(%%ebx), %%esp\n" );
 709     }
 710     else
 711     {
 712         fprintf( outfile, "\tmovzwl %%bp, %%ebx\n" );
 713         fprintf( outfile, "\tsubw %%bp, %%sp\n" );
 714         fprintf( outfile, "\tmovzwl %%sp, %%ebp\n" );
 715         fprintf( outfile, "\tlssl %%ss:-12(%%ebx), %%esp\n" );
 716     }
 717     fprintf( outfile, "\tlret\n" );
 718     output_function_size( outfile, isEx ? "CALL32_CBClientEx_Ret" : "CALL32_CBClient_Ret" );
 719 }
 720
 721
 722 /*******************************************************************
 723  *         BuildCallFrom32Regs
 724  *
 725  * Build a 32-bit-to-Wine call-back function for a 'register' function.
 726  * 'args' is the number of dword arguments.
 727  *
 728  * Stack layout:
 729  *   ...
 730  * (ebp+16)  first arg
 731  * (ebp+12)  ret addr to user code
 732  * (ebp+8)   eax saved by relay code
 733  * (ebp+4)   ret addr to relay code
 734  * (ebp+0)   saved ebp
 735  * (ebp-128) buffer area to allow stack frame manipulation
 736  * (ebp-332) CONTEXT86 struct
 737  * (ebp-336) padding for stack alignment
 738  * (ebp-336-n) CONTEXT86 *argument
 739  *  ....     other arguments copied from (ebp+12)
 740  *
 741  * The entry point routine is called with a CONTEXT* extra argument,
 742  * following the normal args. In this context structure, EIP_reg
 743  * contains the return address to user code, and ESP_reg the stack
 744  * pointer on return (with the return address and arguments already
 745  * removed).
 746  */
 747 static void BuildCallFrom32Regs( FILE *outfile )
 748 {
 749     static const int STACK_SPACE = 128 + sizeof(CONTEXT86);
 750
 751     /* Function header */
 752
 753     function_header( outfile, "__wine_call_from_32_regs" );
 754
 755     /* Allocate some buffer space on the stack */
 756
 757     fprintf( outfile, "\tpushl %%ebp\n" );
 758     fprintf( outfile, "\tmovl %%esp,%%ebp\n ");
 759     fprintf( outfile, "\tleal -%d(%%esp), %%esp\n", STACK_SPACE + 4 /* for context arg */);
 760
 761     /* Build the context structure */
 762
 763     fprintf( outfile, "\tpushfl\n" );
 764     fprintf( outfile, "\tpopl %%eax\n" );
 765     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(EFlags) - STACK_SPACE );
 766     fprintf( outfile, "\tmovl 0(%%ebp),%%eax\n" );
 767     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(Ebp) - STACK_SPACE );
 768     fprintf( outfile, "\tmovl 8(%%ebp),%%eax\n" );
 769     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(Eax) - STACK_SPACE );
 770     fprintf( outfile, "\tmovl %%ebx,%d(%%ebp)\n", CONTEXTOFFSET(Ebx) - STACK_SPACE );
 771     fprintf( outfile, "\tmovl %%ecx,%d(%%ebp)\n", CONTEXTOFFSET(Ecx) - STACK_SPACE );
 772     fprintf( outfile, "\tmovl %%edx,%d(%%ebp)\n", CONTEXTOFFSET(Edx) - STACK_SPACE );
 773     fprintf( outfile, "\tmovl %%esi,%d(%%ebp)\n", CONTEXTOFFSET(Esi) - STACK_SPACE );
 774     fprintf( outfile, "\tmovl %%edi,%d(%%ebp)\n", CONTEXTOFFSET(Edi) - STACK_SPACE );
 775
 776     fprintf( outfile, "\txorl %%eax,%%eax\n" );
 777     fprintf( outfile, "\tmovw %%cs,%%ax\n" );
 778     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(SegCs) - STACK_SPACE );
 779     fprintf( outfile, "\tmovw %%es,%%ax\n" );
 780     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(SegEs) - STACK_SPACE );
 781     fprintf( outfile, "\tmovw %%fs,%%ax\n" );
 782     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(SegFs) - STACK_SPACE );
 783     fprintf( outfile, "\tmovw %%gs,%%ax\n" );
 784     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(SegGs) - STACK_SPACE );
 785     fprintf( outfile, "\tmovw %%ss,%%ax\n" );
 786     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(SegSs) - STACK_SPACE );
 787     fprintf( outfile, "\tmovw %%ds,%%ax\n" );
 788     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(SegDs) - STACK_SPACE );
 789     fprintf( outfile, "\tmovw %%ax,%%es\n" );  /* set %es equal to %ds just in case */
 790
 791     fprintf( outfile, "\tmovl $0x%x,%%eax\n", CONTEXT86_FULL );
 792     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(ContextFlags) - STACK_SPACE );
 793
 794     fprintf( outfile, "\tmovl 12(%%ebp),%%eax\n" ); /* Get %eip at time of call */
 795     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(Eip) - STACK_SPACE );
 796
 797     /* Transfer the arguments */
 798
 799     fprintf( outfile, "\tmovl 4(%%ebp),%%ebx\n" );   /* get relay code addr */
 800     fprintf( outfile, "\tmovzbl 4(%%ebx),%%ecx\n" ); /* fetch number of args to copy */
 801     fprintf( outfile, "\tsubl %%ecx,%%esp\n" );
 802     fprintf( outfile, "\tandl $~15,%%esp\n" );
 803     fprintf( outfile, "\tleal 16(%%ebp),%%esi\n" );  /* get %esp at time of call */
 804     fprintf( outfile, "\tmovl %%esp,%%edi\n" );
 805     fprintf( outfile, "\tshrl $2,%%ecx\n" );
 806     fprintf( outfile, "\tjz 1f\n" );
 807     fprintf( outfile, "\tcld\n" );
 808     fprintf( outfile, "\trep\n\tmovsl\n" );  /* copy args */
 809     fprintf( outfile, "1:\tleal %d(%%ebp),%%eax\n", -STACK_SPACE );  /* get addr of context struct */
 810     fprintf( outfile, "\tmovl %%eax,(%%edi)\n" );    /* and pass it as extra arg */
 811     fprintf( outfile, "\tmovzbl 5(%%ebx),%%eax\n" ); /* fetch number of args to remove */
 812     fprintf( outfile, "\tleal 16(%%ebp,%%eax),%%eax\n" );
 813     fprintf( outfile, "\tmovl %%eax,%d(%%ebp)\n", CONTEXTOFFSET(Esp) - STACK_SPACE );
 814
 815     /* Call the entry point */
 816
 817     fprintf( outfile, "\taddl (%%ebx),%%ebx\n" );
 818     fprintf( outfile, "\tcall *%%ebx\n" );
 819     fprintf( outfile, "\tleal -%d(%%ebp),%%ecx\n", STACK_SPACE );
 820
 821     /* Restore the context structure */
 822
 823     fprintf( outfile, "2:\tpushl %d(%%ecx)\n", CONTEXTOFFSET(SegEs) );
 824     fprintf( outfile, "\tpopl %%es\n" );
 825     fprintf( outfile, "\tpushl %d(%%ecx)\n", CONTEXTOFFSET(SegFs) );
 826     fprintf( outfile, "\tpopl %%fs\n" );
 827     fprintf( outfile, "\tpushl %d(%%ecx)\n", CONTEXTOFFSET(SegGs) );
 828     fprintf( outfile, "\tpopl %%gs\n" );
 829
 830     fprintf( outfile, "\tmovl %d(%%ecx),%%edi\n", CONTEXTOFFSET(Edi) );
 831     fprintf( outfile, "\tmovl %d(%%ecx),%%esi\n", CONTEXTOFFSET(Esi) );
 832     fprintf( outfile, "\tmovl %d(%%ecx),%%edx\n", CONTEXTOFFSET(Edx) );
 833     fprintf( outfile, "\tmovl %d(%%ecx),%%ebx\n", CONTEXTOFFSET(Ebx) );
 834     fprintf( outfile, "\tmovl %d(%%ecx),%%eax\n", CONTEXTOFFSET(Eax) );
 835     fprintf( outfile, "\tmovl %d(%%ecx),%%ebp\n", CONTEXTOFFSET(Ebp) );
 836
 837     fprintf( outfile, "\tpushl %d(%%ecx)\n", CONTEXTOFFSET(SegSs) );
 838     fprintf( outfile, "\tpopl %%ss\n" );
 839     fprintf( outfile, "\tmovl %d(%%ecx),%%esp\n", CONTEXTOFFSET(Esp) );
 840
 841     fprintf( outfile, "\tpushl %d(%%ecx)\n", CONTEXTOFFSET(EFlags) );
 842     fprintf( outfile, "\tpushl %d(%%ecx)\n", CONTEXTOFFSET(SegCs) );
 843     fprintf( outfile, "\tpushl %d(%%ecx)\n", CONTEXTOFFSET(Eip) );
 844     fprintf( outfile, "\tpushl %d(%%ecx)\n", CONTEXTOFFSET(SegDs) );
 845     fprintf( outfile, "\tmovl %d(%%ecx),%%ecx\n", CONTEXTOFFSET(Ecx) );
 846
 847     fprintf( outfile, "\tpopl %%ds\n" );
 848     fprintf( outfile, "\tiret\n" );
 849     output_function_size( outfile, "__wine_call_from_32_regs" );
 850
 851     function_header( outfile, "__wine_call_from_32_restore_regs" );
 852     fprintf( outfile, "\tleal 4(%%esp),%%ecx\n" );
 853     fprintf( outfile, "\tjmp 2b\n" );
 854     output_function_size( outfile, "__wine_call_from_32_restore_regs" );
 855 }
 856
 857
 858 /*******************************************************************
 859  *         BuildPendingEventCheck
 860  *
 861  * Build a function that checks whether there are any
 862  * pending DPMI events.
 863  *
 864  * Stack layout:
 865  *
 866  * (sp+12) long   eflags
 867  * (sp+6)  long   cs
 868  * (sp+2)  long   ip
 869  * (sp)    word   fs
 870  *
 871  * On entry to function, fs register points to a valid TEB.
 872  * On exit from function, stack will be popped.
 873  */
 874 static void BuildPendingEventCheck( FILE *outfile )
 875 {
 876     /* Function header */
 877
 878     function_header( outfile, "DPMI_PendingEventCheck" );
 879
 880     /* Check for pending events. */
 881
 882     fprintf( outfile, "\t.byte 0x64\n\ttestl $0xffffffff,(%d)\n",
 883              STRUCTOFFSET(TEB,vm86_pending) );
 884     fprintf( outfile, "\tje %s\n", asm_name("DPMI_PendingEventCheck_Cleanup") );
 885
 886     fprintf( outfile, "\t.byte 0x64\n\ttestl $0xffffffff,(%d)\n",
 887              STRUCTOFFSET(TEB,dpmi_vif) );
 888
 889     fprintf( outfile, "\tje %s\n", asm_name("DPMI_PendingEventCheck_Cleanup") );
 890
 891     /* Process pending events. */
 892
 893     fprintf( outfile, "\tsti\n" );
 894
 895     /* Start cleanup. Restore fs register. */
 896
 897     fprintf( outfile, "%s\n", asm_globl("DPMI_PendingEventCheck_Cleanup") );
 898     fprintf( outfile, "\tpopw %%fs\n" );
 899
 900     /* Return from function. */
 901
 902     fprintf( outfile, "%s\n", asm_globl("DPMI_PendingEventCheck_Return") );
 903     fprintf( outfile, "\tiret\n" );
 904
 905     output_function_size( outfile, "DPMI_PendingEventCheck" );
 906 }
 907
 908
 909 /*******************************************************************
 910  *         BuildRelays16
 911  *
 912  * Build all the 16-bit relay callbacks
 913  */
 914 void BuildRelays16( FILE *outfile )
 915 {
 916     if (target_cpu != CPU_x86)
 917     {
 918         fprintf( outfile, "/* File not used with this architecture. Do not edit! */\n\n" );
 919         return;
 920     }
 921
 922     /* File header */
 923
 924     fprintf( outfile, "/* File generated automatically. Do not edit! */\n\n" );
 925     fprintf( outfile, "\t.text\n" );
 926
 927     fprintf( outfile, "%s:\n\n", asm_name("__wine_spec_thunk_text_16") );
 928
 929     fprintf( outfile, "%s\n", asm_globl("__wine_call16_start") );
 930
 931     /* Standard CallFrom16 routine */
 932     BuildCallFrom16Core( outfile, FALSE, FALSE );
 933
 934     /* Register CallFrom16 routine */
 935     BuildCallFrom16Core( outfile, TRUE, FALSE );
 936
 937     /* C16ThkSL CallFrom16 routine */
 938     BuildCallFrom16Core( outfile, FALSE, TRUE );
 939
 940     /* Standard CallTo16 routine */
 941     BuildCallTo16Core( outfile, 0 );
 942
 943     /* Register CallTo16 routine */
 944     BuildCallTo16Core( outfile, 1 );
 945
 946     /* Standard CallTo16 return stub */
 947     BuildRet16Func( outfile );
 948
 949     /* CBClientThunkSL routine */
 950     BuildCallTo32CBClient( outfile, FALSE );
 951
 952     /* CBClientThunkSLEx routine */
 953     BuildCallTo32CBClient( outfile, TRUE  );
 954
 955     /* Pending DPMI events check stub */
 956     BuildPendingEventCheck( outfile );
 957
 958     fprintf( outfile, "%s\n", asm_globl("__wine_call16_end") );
 959     output_function_size( outfile, "__wine_spec_thunk_text_16" );
 960
 961     /* Declare the return address and data selector variables */
 962     fprintf( outfile, "\n\t.data\n\t.align %d\n", get_alignment(4) );
 963     fprintf( outfile, "%s\n\t.long 0\n", asm_globl("CallTo16_DataSelector") );
 964     fprintf( outfile, "%s\n\t.long 0\n", asm_globl("CallTo16_TebSelector") );
 965     if (UsePIC) fprintf( outfile, "wine_ldt_copy_ptr:\t.long %s\n", asm_name("wine_ldt_copy") );
 966 }
 967
 968 /*******************************************************************
 969  *         BuildRelays32
 970  *
 971  * Build all the 32-bit relay callbacks
 972  */
 973 void BuildRelays32( FILE *outfile )
 974 {
 975     if (target_cpu != CPU_x86)
 976     {
 977         fprintf( outfile, "/* File not used with this architecture. Do not edit! */\n\n" );
 978         return;
 979     }
 980
 981     /* File header */
 982
 983     fprintf( outfile, "/* File generated automatically. Do not edit! */\n\n" );
 984     fprintf( outfile, "\t.text\n" );
 985     fprintf( outfile, "%s:\n\n", asm_name("__wine_spec_thunk_text_32") );
 986
 987     /* 32-bit register entry point */
 988     BuildCallFrom32Regs( outfile );
 989
 990     output_function_size( outfile, "__wine_spec_thunk_text_32" );
 991 }