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-rw-r--r--src/qcommon/vm_x86.c1207
1 files changed, 1207 insertions, 0 deletions
diff --git a/src/qcommon/vm_x86.c b/src/qcommon/vm_x86.c
new file mode 100644
index 00000000..38593c6b
--- /dev/null
+++ b/src/qcommon/vm_x86.c
@@ -0,0 +1,1207 @@
+/*
+===========================================================================
+Copyright (C) 1999-2005 Id Software, Inc.
+
+This file is part of Quake III Arena source code.
+
+Quake III Arena source code is free software; you can redistribute it
+and/or modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation; either version 2 of the License,
+or (at your option) any later version.
+
+Quake III Arena source code is distributed in the hope that it will be
+useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with Quake III Arena source code; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+===========================================================================
+*/
+// vm_x86.c -- load time compiler and execution environment for x86
+
+#include "vm_local.h"
+
+#ifdef __FreeBSD__ // rb0101023
+#include <sys/types.h>
+#endif
+
+#ifndef _WIN32
+#include <sys/mman.h> // for PROT_ stuff
+#endif
+
+/*
+
+ eax scratch
+ ebx scratch
+ ecx scratch (required for shifts)
+ edx scratch (required for divisions)
+ esi program stack
+ edi opstack
+
+*/
+
+// TTimo: initialised the statics, this fixes a crash when entering a compiled VM
+static byte *buf = NULL;
+static byte *jused = NULL;
+static int compiledOfs = 0;
+static byte *code = NULL;
+static int pc = 0;
+
+static int *instructionPointers = NULL;
+
+#define FTOL_PTR
+
+#ifdef _MSC_VER
+
+#if defined( FTOL_PTR )
+int _ftol( float );
+static int ftolPtr = (int)_ftol;
+#endif
+
+void AsmCall( void );
+static int asmCallPtr = (int)AsmCall;
+
+#else // _MSC_VER
+
+#if defined( FTOL_PTR )
+// bk001213 - BEWARE: does not work! UI menu etc. broken - stack!
+// bk001119 - added: int gftol( float x ) { return (int)x; }
+
+int qftol( void ); // bk001213 - label, see unix/ftol.nasm
+int qftol027F( void ); // bk001215 - fixed FPU control variants
+int qftol037F( void );
+int qftol0E7F( void ); // bk010102 - fixed bogus bits (duh)
+int qftol0F7F( void );
+
+
+static int ftolPtr = (int)qftol0F7F;
+#endif // FTOL_PTR
+
+void doAsmCall( void );
+static int asmCallPtr = (int)doAsmCall;
+#endif
+
+
+static int callMask = 0; // bk001213 - init
+
+static int instruction, pass;
+static int lastConst = 0;
+static int oc0, oc1, pop0, pop1;
+
+typedef enum
+{
+ LAST_COMMAND_NONE = 0,
+ LAST_COMMAND_MOV_EDI_EAX,
+ LAST_COMMAND_SUB_DI_4,
+ LAST_COMMAND_SUB_DI_8,
+} ELastCommand;
+
+static ELastCommand LastCommand;
+
+/*
+=================
+AsmCall
+=================
+*/
+#ifdef _MSC_VER
+__declspec( naked ) void AsmCall( void ) {
+int programStack;
+int *opStack;
+int syscallNum;
+vm_t* savedVM;
+
+__asm {
+ mov eax, dword ptr [edi]
+ sub edi, 4
+ or eax,eax
+ jl systemCall
+ // calling another vm function
+ shl eax,2
+ add eax, dword ptr [instructionPointers]
+ call dword ptr [eax]
+ mov eax, dword ptr [edi]
+ and eax, [callMask]
+ ret
+systemCall:
+
+ // convert negative num to system call number
+ // and store right before the first arg
+ neg eax
+ dec eax
+
+ push ebp
+ mov ebp, esp
+ sub esp, __LOCAL_SIZE
+
+ mov dword ptr syscallNum, eax // so C code can get at it
+ mov dword ptr programStack, esi // so C code can get at it
+ mov dword ptr opStack, edi
+
+ push ecx
+ push esi // we may call recursively, so the
+ push edi // statics aren't guaranteed to be around
+}
+
+ savedVM = currentVM;
+
+ // save the stack to allow recursive VM entry
+ currentVM->programStack = programStack - 4;
+ *(int *)((byte *)currentVM->dataBase + programStack + 4) = syscallNum;
+//VM_LogSyscalls( (int *)((byte *)currentVM->dataBase + programStack + 4) );
+ *(opStack+1) = currentVM->systemCall( (int *)((byte *)currentVM->dataBase + programStack + 4) );
+
+ currentVM = savedVM;
+
+_asm {
+ pop edi
+ pop esi
+ pop ecx
+ add edi, 4 // we added the return value
+
+ mov esp, ebp
+ pop ebp
+
+ ret
+}
+
+}
+
+#else //!_MSC_VER
+
+#ifdef __MINGW32__ // _ is prepended to compiled symbols
+#define CMANG(sym) "_"#sym
+#else
+#define CMANG(sym) #sym
+#endif
+
+static int callProgramStack;
+static int *callOpStack;
+static int callSyscallNum;
+
+void callAsmCall(void)
+{
+ vm_t *savedVM;
+ int *callOpStack2;
+
+ savedVM = currentVM;
+ callOpStack2 = callOpStack;
+
+ // save the stack to allow recursive VM entry
+ currentVM->programStack = callProgramStack - 4;
+ *(int *)((byte *)currentVM->dataBase + callProgramStack + 4) = callSyscallNum;
+ //VM_LogSyscalls((int *)((byte *)currentVM->dataBase + callProgramStack + 4) );
+ *(callOpStack2+1) = currentVM->systemCall( (long *)((byte *)currentVM->dataBase + callProgramStack + 4) );
+
+ currentVM = savedVM;
+}
+
+// Note the C space function AsmCall is never actually called, and is in fact
+// arbitrarily named (though this is not true for the MSC version). When a vm
+// makes a system call, control jumps straight to the doAsmCall label.
+void AsmCall( void ) {
+ asm( CMANG(doAsmCall) ": \n\t" \
+ " movl (%%edi),%%eax \n\t" \
+ " subl $4,%%edi \n\t" \
+ " orl %%eax,%%eax \n\t" \
+ " jl systemCall \n\t" \
+ " shll $2,%%eax \n\t" \
+ " addl %3,%%eax \n\t" \
+ " call *(%%eax) \n\t" \
+ " movl (%%edi),%%eax \n\t" \
+ " andl " CMANG(callMask) ", %%eax \n\t" \
+ " jmp doret \n\t" \
+ "systemCall: \n\t" \
+ " negl %%eax \n\t" \
+ " decl %%eax \n\t" \
+ " movl %%eax,%0 \n\t" \
+ " movl %%esi,%1 \n\t" \
+ " movl %%edi,%2 \n\t" \
+ " pushl %%ecx \n\t" \
+ " pushl %%esi \n\t" \
+ " pushl %%edi \n\t" \
+ " call " CMANG(callAsmCall) " \n\t" \
+ " popl %%edi \n\t" \
+ " popl %%esi \n\t" \
+ " popl %%ecx \n\t" \
+ " addl $4,%%edi \n\t" \
+ "doret: \n\t" \
+ " ret \n\t" \
+ : "=rm" (callSyscallNum), "=rm" (callProgramStack), "=rm" (callOpStack) \
+ : "rm" (instructionPointers) \
+ : "ax", "di", "si", "cx" \
+ );
+}
+#endif
+
+static int Constant4( void ) {
+ int v;
+
+ v = code[pc] | (code[pc+1]<<8) | (code[pc+2]<<16) | (code[pc+3]<<24);
+ pc += 4;
+ return v;
+}
+
+static int Constant1( void ) {
+ int v;
+
+ v = code[pc];
+ pc += 1;
+ return v;
+}
+
+static void Emit1( int v )
+{
+ buf[ compiledOfs ] = v;
+ compiledOfs++;
+
+ LastCommand = LAST_COMMAND_NONE;
+}
+
+#if 0
+static void Emit2( int v ) {
+ Emit1( v & 255 );
+ Emit1( ( v >> 8 ) & 255 );
+}
+#endif
+
+static void Emit4( int v ) {
+ Emit1( v & 255 );
+ Emit1( ( v >> 8 ) & 255 );
+ Emit1( ( v >> 16 ) & 255 );
+ Emit1( ( v >> 24 ) & 255 );
+}
+
+static int Hex( int c ) {
+ if ( c >= 'a' && c <= 'f' ) {
+ return 10 + c - 'a';
+ }
+ if ( c >= 'A' && c <= 'F' ) {
+ return 10 + c - 'A';
+ }
+ if ( c >= '0' && c <= '9' ) {
+ return c - '0';
+ }
+
+ Com_Error( ERR_DROP, "Hex: bad char '%c'", c );
+
+ return 0;
+}
+static void EmitString( const char *string ) {
+ int c1, c2;
+ int v;
+
+ while ( 1 ) {
+ c1 = string[0];
+ c2 = string[1];
+
+ v = ( Hex( c1 ) << 4 ) | Hex( c2 );
+ Emit1( v );
+
+ if ( !string[2] ) {
+ break;
+ }
+ string += 3;
+ }
+}
+
+
+
+static void EmitCommand(ELastCommand command)
+{
+ switch(command)
+ {
+ case LAST_COMMAND_MOV_EDI_EAX:
+ EmitString( "89 07" ); // mov dword ptr [edi], eax
+ break;
+
+ case LAST_COMMAND_SUB_DI_4:
+ EmitString( "83 EF 04" ); // sub edi, 4
+ break;
+
+ case LAST_COMMAND_SUB_DI_8:
+ EmitString( "83 EF 08" ); // sub edi, 8
+ break;
+ default:
+ break;
+ }
+ LastCommand = command;
+}
+
+static void EmitAddEDI4(vm_t *vm) {
+ if (LastCommand == LAST_COMMAND_SUB_DI_4 && jused[instruction-1] == 0)
+ { // sub di,4
+ compiledOfs -= 3;
+ vm->instructionPointers[ instruction-1 ] = compiledOfs;
+ return;
+ }
+ if (LastCommand == LAST_COMMAND_SUB_DI_8 && jused[instruction-1] == 0)
+ { // sub di,8
+ compiledOfs -= 3;
+ vm->instructionPointers[ instruction-1 ] = compiledOfs;
+ EmitString( "83 EF 04" ); // sub edi,4
+ return;
+ }
+ EmitString( "83 C7 04" ); // add edi,4
+}
+
+static void EmitMovEAXEDI(vm_t *vm) {
+ if (LastCommand == LAST_COMMAND_MOV_EDI_EAX)
+ { // mov [edi], eax
+ compiledOfs -= 2;
+ vm->instructionPointers[ instruction-1 ] = compiledOfs;
+ return;
+ }
+ if (pop1 == OP_DIVI || pop1 == OP_DIVU || pop1 == OP_MULI || pop1 == OP_MULU ||
+ pop1 == OP_STORE4 || pop1 == OP_STORE2 || pop1 == OP_STORE1 )
+ {
+ return;
+ }
+ if (pop1 == OP_CONST && buf[compiledOfs-6] == 0xC7 && buf[compiledOfs-5] == 0x07 )
+ { // mov edi, 0x123456
+ compiledOfs -= 6;
+ vm->instructionPointers[ instruction-1 ] = compiledOfs;
+ EmitString( "B8" ); // mov eax, 0x12345678
+ Emit4( lastConst );
+ return;
+ }
+ EmitString( "8B 07" ); // mov eax, dword ptr [edi]
+}
+
+qboolean EmitMovEBXEDI(vm_t *vm, int andit) {
+ if (LastCommand == LAST_COMMAND_MOV_EDI_EAX)
+ { // mov [edi], eax
+ compiledOfs -= 2;
+ vm->instructionPointers[ instruction-1 ] = compiledOfs;
+ EmitString( "8B D8"); // mov bx, eax
+ return qfalse;
+ }
+ if (pop1 == OP_DIVI || pop1 == OP_DIVU || pop1 == OP_MULI || pop1 == OP_MULU ||
+ pop1 == OP_STORE4 || pop1 == OP_STORE2 || pop1 == OP_STORE1 )
+ {
+ EmitString( "8B D8"); // mov bx, eax
+ return qfalse;
+ }
+ if (pop1 == OP_CONST && buf[compiledOfs-6] == 0xC7 && buf[compiledOfs-5] == 0x07 )
+ { // mov edi, 0x123456
+ compiledOfs -= 6;
+ vm->instructionPointers[ instruction-1 ] = compiledOfs;
+ EmitString( "BB" ); // mov ebx, 0x12345678
+ if (andit) {
+ Emit4( lastConst & andit );
+ } else {
+ Emit4( lastConst );
+ }
+ return qtrue;
+ }
+
+ EmitString( "8B 1F" ); // mov ebx, dword ptr [edi]
+ return qfalse;
+}
+
+/*
+=================
+VM_Compile
+=================
+*/
+void VM_Compile( vm_t *vm, vmHeader_t *header ) {
+ int op;
+ int maxLength;
+ int v;
+ int i;
+ qboolean opt;
+
+ // allocate a very large temp buffer, we will shrink it later
+ maxLength = header->codeLength * 8;
+ buf = Z_Malloc( maxLength );
+ jused = Z_Malloc(header->instructionCount + 2 );
+
+ Com_Memset(jused, 0, header->instructionCount+2);
+
+ // ensure that the optimisation pass knows about all the jump
+ // table targets
+ for( i = 0; i < vm->numJumpTableTargets; i++ ) {
+ jused[ *(int *)(vm->jumpTableTargets + ( i * sizeof( int ) ) ) ] = 1;
+ }
+
+ for(pass=0;pass<2;pass++) {
+ oc0 = -23423;
+ oc1 = -234354;
+ pop0 = -43435;
+ pop1 = -545455;
+
+ // translate all instructions
+ pc = 0;
+ instruction = 0;
+ code = (byte *)header + header->codeOffset;
+ compiledOfs = 0;
+
+ LastCommand = LAST_COMMAND_NONE;
+
+ while ( instruction < header->instructionCount ) {
+ if ( compiledOfs > maxLength - 16 ) {
+ Com_Error( ERR_FATAL, "VM_CompileX86: maxLength exceeded" );
+ }
+
+ vm->instructionPointers[ instruction ] = compiledOfs;
+ instruction++;
+
+ if ( pc > header->codeLength ) {
+ Com_Error( ERR_FATAL, "VM_CompileX86: pc > header->codeLength" );
+ }
+
+ op = code[ pc ];
+ pc++;
+ switch ( op ) {
+ case 0:
+ break;
+ case OP_BREAK:
+ EmitString( "CC" ); // int 3
+ break;
+ case OP_ENTER:
+ EmitString( "81 EE" ); // sub esi, 0x12345678
+ Emit4( Constant4() );
+ break;
+ case OP_CONST:
+ if (code[pc+4] == OP_LOAD4) {
+ EmitAddEDI4(vm);
+ EmitString( "BB" ); // mov ebx, 0x12345678
+ Emit4( (Constant4()&vm->dataMask) + (int)vm->dataBase);
+ EmitString( "8B 03" ); // mov eax, dword ptr [ebx]
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+ pc++; // OP_LOAD4
+ instruction += 1;
+ break;
+ }
+ if (code[pc+4] == OP_LOAD2) {
+ EmitAddEDI4(vm);
+ EmitString( "BB" ); // mov ebx, 0x12345678
+ Emit4( (Constant4()&vm->dataMask) + (int)vm->dataBase);
+ EmitString( "0F B7 03" ); // movzx eax, word ptr [ebx]
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+ pc++; // OP_LOAD4
+ instruction += 1;
+ break;
+ }
+ if (code[pc+4] == OP_LOAD1) {
+ EmitAddEDI4(vm);
+ EmitString( "BB" ); // mov ebx, 0x12345678
+ Emit4( (Constant4()&vm->dataMask) + (int)vm->dataBase);
+ EmitString( "0F B6 03" ); // movzx eax, byte ptr [ebx]
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+ pc++; // OP_LOAD4
+ instruction += 1;
+ break;
+ }
+ if (code[pc+4] == OP_STORE4) {
+ opt = EmitMovEBXEDI(vm, (vm->dataMask & ~3));
+ EmitString( "B8" ); // mov eax, 0x12345678
+ Emit4( Constant4() );
+// if (!opt) {
+// EmitString( "81 E3" ); // and ebx, 0x12345678
+// Emit4( vm->dataMask & ~3 );
+// }
+ EmitString( "89 83" ); // mov dword ptr [ebx+0x12345678], eax
+ Emit4( (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ pc++; // OP_STORE4
+ instruction += 1;
+ break;
+ }
+ if (code[pc+4] == OP_STORE2) {
+ opt = EmitMovEBXEDI(vm, (vm->dataMask & ~1));
+ EmitString( "B8" ); // mov eax, 0x12345678
+ Emit4( Constant4() );
+// if (!opt) {
+// EmitString( "81 E3" ); // and ebx, 0x12345678
+// Emit4( vm->dataMask & ~1 );
+// }
+ EmitString( "66 89 83" ); // mov word ptr [ebx+0x12345678], eax
+ Emit4( (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ pc++; // OP_STORE4
+ instruction += 1;
+ break;
+ }
+ if (code[pc+4] == OP_STORE1) {
+ opt = EmitMovEBXEDI(vm, vm->dataMask);
+ EmitString( "B8" ); // mov eax, 0x12345678
+ Emit4( Constant4() );
+// if (!opt) {
+// EmitString( "81 E3" ); // and ebx, 0x12345678
+// Emit4( vm->dataMask );
+// }
+ EmitString( "88 83" ); // mov byte ptr [ebx+0x12345678], eax
+ Emit4( (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ pc++; // OP_STORE4
+ instruction += 1;
+ break;
+ }
+ if (code[pc+4] == OP_ADD) {
+ EmitString( "81 07" ); // add dword ptr [edi], 0x1234567
+ Emit4( Constant4() );
+ pc++; // OP_ADD
+ instruction += 1;
+ break;
+ }
+ if (code[pc+4] == OP_SUB) {
+ EmitString( "81 2F" ); // sub dword ptr [edi], 0x1234567
+ Emit4( Constant4() );
+ pc++; // OP_ADD
+ instruction += 1;
+ break;
+ }
+ EmitAddEDI4(vm);
+ EmitString( "C7 07" ); // mov dword ptr [edi], 0x12345678
+ lastConst = Constant4();
+ Emit4( lastConst );
+ if (code[pc] == OP_JUMP) {
+ jused[lastConst] = 1;
+ }
+ break;
+ case OP_LOCAL:
+ EmitAddEDI4(vm);
+ EmitString( "8D 86" ); // lea eax, [0x12345678 + esi]
+ oc0 = oc1;
+ oc1 = Constant4();
+ Emit4( oc1 );
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+ break;
+ case OP_ARG:
+ EmitMovEAXEDI(vm); // mov eax,dword ptr [edi]
+ EmitString( "89 86" ); // mov dword ptr [esi+database],eax
+ // FIXME: range check
+ Emit4( Constant1() + (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_CALL:
+ EmitString( "C7 86" ); // mov dword ptr [esi+database],0x12345678
+ Emit4( (int)vm->dataBase );
+ Emit4( pc );
+ EmitString( "FF 15" ); // call asmCallPtr
+ Emit4( (int)&asmCallPtr );
+ break;
+ case OP_PUSH:
+ EmitAddEDI4(vm);
+ break;
+ case OP_POP:
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_LEAVE:
+ v = Constant4();
+ EmitString( "81 C6" ); // add esi, 0x12345678
+ Emit4( v );
+ EmitString( "C3" ); // ret
+ break;
+ case OP_LOAD4:
+ if (code[pc] == OP_CONST && code[pc+5] == OP_ADD && code[pc+6] == OP_STORE4) {
+ if (oc0 == oc1 && pop0 == OP_LOCAL && pop1 == OP_LOCAL) {
+ compiledOfs -= 11;
+ vm->instructionPointers[ instruction-1 ] = compiledOfs;
+ }
+ pc++; // OP_CONST
+ v = Constant4();
+ EmitMovEBXEDI(vm, vm->dataMask);
+ if (v == 1 && oc0 == oc1 && pop0 == OP_LOCAL && pop1 == OP_LOCAL) {
+ EmitString( "FF 83"); // inc dword ptr [ebx + 0x12345678]
+ Emit4( (int)vm->dataBase );
+ } else {
+ EmitString( "8B 83" ); // mov eax, dword ptr [ebx + 0x12345678]
+ Emit4( (int)vm->dataBase );
+ EmitString( "05" ); // add eax, const
+ Emit4( v );
+ if (oc0 == oc1 && pop0 == OP_LOCAL && pop1 == OP_LOCAL) {
+ EmitString( "89 83" ); // mov dword ptr [ebx+0x12345678], eax
+ Emit4( (int)vm->dataBase );
+ } else {
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ EmitString( "8B 1F" ); // mov ebx, dword ptr [edi]
+ EmitString( "89 83" ); // mov dword ptr [ebx+0x12345678], eax
+ Emit4( (int)vm->dataBase );
+ }
+ }
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ pc++; // OP_ADD
+ pc++; // OP_STORE
+ instruction += 3;
+ break;
+ }
+
+ if (code[pc] == OP_CONST && code[pc+5] == OP_SUB && code[pc+6] == OP_STORE4) {
+ if (oc0 == oc1 && pop0 == OP_LOCAL && pop1 == OP_LOCAL) {
+ compiledOfs -= 11;
+ vm->instructionPointers[ instruction-1 ] = compiledOfs;
+ }
+ EmitMovEBXEDI(vm, vm->dataMask);
+ EmitString( "8B 83" ); // mov eax, dword ptr [ebx + 0x12345678]
+ Emit4( (int)vm->dataBase );
+ pc++; // OP_CONST
+ v = Constant4();
+ if (v == 1 && oc0 == oc1 && pop0 == OP_LOCAL && pop1 == OP_LOCAL) {
+ EmitString( "FF 8B"); // dec dword ptr [ebx + 0x12345678]
+ Emit4( (int)vm->dataBase );
+ } else {
+ EmitString( "2D" ); // sub eax, const
+ Emit4( v );
+ if (oc0 == oc1 && pop0 == OP_LOCAL && pop1 == OP_LOCAL) {
+ EmitString( "89 83" ); // mov dword ptr [ebx+0x12345678], eax
+ Emit4( (int)vm->dataBase );
+ } else {
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ EmitString( "8B 1F" ); // mov ebx, dword ptr [edi]
+ EmitString( "89 83" ); // mov dword ptr [ebx+0x12345678], eax
+ Emit4( (int)vm->dataBase );
+ }
+ }
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ pc++; // OP_SUB
+ pc++; // OP_STORE
+ instruction += 3;
+ break;
+ }
+
+ if (buf[compiledOfs-2] == 0x89 && buf[compiledOfs-1] == 0x07) {
+ compiledOfs -= 2;
+ vm->instructionPointers[ instruction-1 ] = compiledOfs;
+ EmitString( "8B 80"); // mov eax, dword ptr [eax + 0x1234567]
+ Emit4( (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+ break;
+ }
+ EmitMovEBXEDI(vm, vm->dataMask);
+ EmitString( "8B 83" ); // mov eax, dword ptr [ebx + 0x12345678]
+ Emit4( (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+ break;
+ case OP_LOAD2:
+ EmitMovEBXEDI(vm, vm->dataMask);
+ EmitString( "0F B7 83" ); // movzx eax, word ptr [ebx + 0x12345678]
+ Emit4( (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+ break;
+ case OP_LOAD1:
+ EmitMovEBXEDI(vm, vm->dataMask);
+ EmitString( "0F B6 83" ); // movzx eax, byte ptr [ebx + 0x12345678]
+ Emit4( (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+ break;
+ case OP_STORE4:
+ EmitMovEAXEDI(vm);
+ EmitString( "8B 5F FC" ); // mov ebx, dword ptr [edi-4]
+// if (pop1 != OP_CALL) {
+// EmitString( "81 E3" ); // and ebx, 0x12345678
+// Emit4( vm->dataMask & ~3 );
+// }
+ EmitString( "89 83" ); // mov dword ptr [ebx+0x12345678], eax
+ Emit4( (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ break;
+ case OP_STORE2:
+ EmitMovEAXEDI(vm);
+ EmitString( "8B 5F FC" ); // mov ebx, dword ptr [edi-4]
+// EmitString( "81 E3" ); // and ebx, 0x12345678
+// Emit4( vm->dataMask & ~1 );
+ EmitString( "66 89 83" ); // mov word ptr [ebx+0x12345678], eax
+ Emit4( (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ break;
+ case OP_STORE1:
+ EmitMovEAXEDI(vm);
+ EmitString( "8B 5F FC" ); // mov ebx, dword ptr [edi-4]
+// EmitString( "81 E3" ); // and ebx, 0x12345678
+// Emit4( vm->dataMask );
+ EmitString( "88 83" ); // mov byte ptr [ebx+0x12345678], eax
+ Emit4( (int)vm->dataBase );
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ break;
+
+ case OP_EQ:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "8B 47 04" ); // mov eax, dword ptr [edi+4]
+ EmitString( "3B 47 08" ); // cmp eax, dword ptr [edi+8]
+ EmitString( "75 06" ); // jne +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_NE:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "8B 47 04" ); // mov eax, dword ptr [edi+4]
+ EmitString( "3B 47 08" ); // cmp eax, dword ptr [edi+8]
+ EmitString( "74 06" ); // je +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_LTI:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "8B 47 04" ); // mov eax, dword ptr [edi+4]
+ EmitString( "3B 47 08" ); // cmp eax, dword ptr [edi+8]
+ EmitString( "7D 06" ); // jnl +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_LEI:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "8B 47 04" ); // mov eax, dword ptr [edi+4]
+ EmitString( "3B 47 08" ); // cmp eax, dword ptr [edi+8]
+ EmitString( "7F 06" ); // jnle +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_GTI:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "8B 47 04" ); // mov eax, dword ptr [edi+4]
+ EmitString( "3B 47 08" ); // cmp eax, dword ptr [edi+8]
+ EmitString( "7E 06" ); // jng +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_GEI:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "8B 47 04" ); // mov eax, dword ptr [edi+4]
+ EmitString( "3B 47 08" ); // cmp eax, dword ptr [edi+8]
+ EmitString( "7C 06" ); // jnge +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_LTU:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "8B 47 04" ); // mov eax, dword ptr [edi+4]
+ EmitString( "3B 47 08" ); // cmp eax, dword ptr [edi+8]
+ EmitString( "73 06" ); // jnb +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_LEU:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "8B 47 04" ); // mov eax, dword ptr [edi+4]
+ EmitString( "3B 47 08" ); // cmp eax, dword ptr [edi+8]
+ EmitString( "77 06" ); // jnbe +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_GTU:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "8B 47 04" ); // mov eax, dword ptr [edi+4]
+ EmitString( "3B 47 08" ); // cmp eax, dword ptr [edi+8]
+ EmitString( "76 06" ); // jna +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_GEU:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "8B 47 04" ); // mov eax, dword ptr [edi+4]
+ EmitString( "3B 47 08" ); // cmp eax, dword ptr [edi+8]
+ EmitString( "72 06" ); // jnae +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_EQF:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "D9 47 04" ); // fld dword ptr [edi+4]
+ EmitString( "D8 5F 08" ); // fcomp dword ptr [edi+8]
+ EmitString( "DF E0" ); // fnstsw ax
+ EmitString( "F6 C4 40" ); // test ah,0x40
+ EmitString( "74 06" ); // je +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_NEF:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "D9 47 04" ); // fld dword ptr [edi+4]
+ EmitString( "D8 5F 08" ); // fcomp dword ptr [edi+8]
+ EmitString( "DF E0" ); // fnstsw ax
+ EmitString( "F6 C4 40" ); // test ah,0x40
+ EmitString( "75 06" ); // jne +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_LTF:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "D9 47 04" ); // fld dword ptr [edi+4]
+ EmitString( "D8 5F 08" ); // fcomp dword ptr [edi+8]
+ EmitString( "DF E0" ); // fnstsw ax
+ EmitString( "F6 C4 01" ); // test ah,0x01
+ EmitString( "74 06" ); // je +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_LEF:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "D9 47 04" ); // fld dword ptr [edi+4]
+ EmitString( "D8 5F 08" ); // fcomp dword ptr [edi+8]
+ EmitString( "DF E0" ); // fnstsw ax
+ EmitString( "F6 C4 41" ); // test ah,0x41
+ EmitString( "74 06" ); // je +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_GTF:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "D9 47 04" ); // fld dword ptr [edi+4]
+ EmitString( "D8 5F 08" ); // fcomp dword ptr [edi+8]
+ EmitString( "DF E0" ); // fnstsw ax
+ EmitString( "F6 C4 41" ); // test ah,0x41
+ EmitString( "75 06" ); // jne +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_GEF:
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ EmitString( "D9 47 04" ); // fld dword ptr [edi+4]
+ EmitString( "D8 5F 08" ); // fcomp dword ptr [edi+8]
+ EmitString( "DF E0" ); // fnstsw ax
+ EmitString( "F6 C4 01" ); // test ah,0x01
+ EmitString( "75 06" ); // jne +6
+ EmitString( "FF 25" ); // jmp [0x12345678]
+ v = Constant4();
+ jused[v] = 1;
+ Emit4( (int)vm->instructionPointers + v*4 );
+ break;
+ case OP_NEGI:
+ EmitString( "F7 1F" ); // neg dword ptr [edi]
+ break;
+ case OP_ADD:
+ EmitMovEAXEDI(vm); // mov eax, dword ptr [edi]
+ EmitString( "01 47 FC" ); // add dword ptr [edi-4],eax
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_SUB:
+ EmitMovEAXEDI(vm); // mov eax, dword ptr [edi]
+ EmitString( "29 47 FC" ); // sub dword ptr [edi-4],eax
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_DIVI:
+ EmitString( "8B 47 FC" ); // mov eax,dword ptr [edi-4]
+ EmitString( "99" ); // cdq
+ EmitString( "F7 3F" ); // idiv dword ptr [edi]
+ EmitString( "89 47 FC" ); // mov dword ptr [edi-4],eax
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_DIVU:
+ EmitString( "8B 47 FC" ); // mov eax,dword ptr [edi-4]
+ EmitString( "33 D2" ); // xor edx, edx
+ EmitString( "F7 37" ); // div dword ptr [edi]
+ EmitString( "89 47 FC" ); // mov dword ptr [edi-4],eax
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_MODI:
+ EmitString( "8B 47 FC" ); // mov eax,dword ptr [edi-4]
+ EmitString( "99" ); // cdq
+ EmitString( "F7 3F" ); // idiv dword ptr [edi]
+ EmitString( "89 57 FC" ); // mov dword ptr [edi-4],edx
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_MODU:
+ EmitString( "8B 47 FC" ); // mov eax,dword ptr [edi-4]
+ EmitString( "33 D2" ); // xor edx, edx
+ EmitString( "F7 37" ); // div dword ptr [edi]
+ EmitString( "89 57 FC" ); // mov dword ptr [edi-4],edx
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_MULI:
+ EmitString( "8B 47 FC" ); // mov eax,dword ptr [edi-4]
+ EmitString( "F7 2F" ); // imul dword ptr [edi]
+ EmitString( "89 47 FC" ); // mov dword ptr [edi-4],eax
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_MULU:
+ EmitString( "8B 47 FC" ); // mov eax,dword ptr [edi-4]
+ EmitString( "F7 27" ); // mul dword ptr [edi]
+ EmitString( "89 47 FC" ); // mov dword ptr [edi-4],eax
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_BAND:
+ EmitMovEAXEDI(vm); // mov eax, dword ptr [edi]
+ EmitString( "21 47 FC" ); // and dword ptr [edi-4],eax
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_BOR:
+ EmitMovEAXEDI(vm); // mov eax, dword ptr [edi]
+ EmitString( "09 47 FC" ); // or dword ptr [edi-4],eax
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_BXOR:
+ EmitMovEAXEDI(vm); // mov eax, dword ptr [edi]
+ EmitString( "31 47 FC" ); // xor dword ptr [edi-4],eax
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_BCOM:
+ EmitString( "F7 17" ); // not dword ptr [edi]
+ break;
+ case OP_LSH:
+ EmitString( "8B 0F" ); // mov ecx, dword ptr [edi]
+ EmitString( "D3 67 FC" ); // shl dword ptr [edi-4], cl
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_RSHI:
+ EmitString( "8B 0F" ); // mov ecx, dword ptr [edi]
+ EmitString( "D3 7F FC" ); // sar dword ptr [edi-4], cl
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_RSHU:
+ EmitString( "8B 0F" ); // mov ecx, dword ptr [edi]
+ EmitString( "D3 6F FC" ); // shr dword ptr [edi-4], cl
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_NEGF:
+ EmitString( "D9 07" ); // fld dword ptr [edi]
+ EmitString( "D9 E0" ); // fchs
+ EmitString( "D9 1F" ); // fstp dword ptr [edi]
+ break;
+ case OP_ADDF:
+ EmitString( "D9 47 FC" ); // fld dword ptr [edi-4]
+ EmitString( "D8 07" ); // fadd dword ptr [edi]
+ EmitString( "D9 5F FC" ); // fstp dword ptr [edi-4]
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ break;
+ case OP_SUBF:
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ EmitString( "D9 07" ); // fld dword ptr [edi]
+ EmitString( "D8 67 04" ); // fsub dword ptr [edi+4]
+ EmitString( "D9 1F" ); // fstp dword ptr [edi]
+ break;
+ case OP_DIVF:
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ EmitString( "D9 07" ); // fld dword ptr [edi]
+ EmitString( "D8 77 04" ); // fdiv dword ptr [edi+4]
+ EmitString( "D9 1F" ); // fstp dword ptr [edi]
+ break;
+ case OP_MULF:
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ EmitString( "D9 07" ); // fld dword ptr [edi]
+ EmitString( "D8 4f 04" ); // fmul dword ptr [edi+4]
+ EmitString( "D9 1F" ); // fstp dword ptr [edi]
+ break;
+ case OP_CVIF:
+ EmitString( "DB 07" ); // fild dword ptr [edi]
+ EmitString( "D9 1F" ); // fstp dword ptr [edi]
+ break;
+ case OP_CVFI:
+#ifndef FTOL_PTR // WHENHELLISFROZENOVER // bk001213 - was used in 1.17
+ // not IEEE complient, but simple and fast
+ EmitString( "D9 07" ); // fld dword ptr [edi]
+ EmitString( "DB 1F" ); // fistp dword ptr [edi]
+#else // FTOL_PTR
+ // call the library conversion function
+ EmitString( "D9 07" ); // fld dword ptr [edi]
+ EmitString( "FF 15" ); // call ftolPtr
+ Emit4( (int)&ftolPtr );
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+#endif
+ break;
+ case OP_SEX8:
+ EmitString( "0F BE 07" ); // movsx eax, byte ptr [edi]
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+ break;
+ case OP_SEX16:
+ EmitString( "0F BF 07" ); // movsx eax, word ptr [edi]
+ EmitCommand(LAST_COMMAND_MOV_EDI_EAX); // mov dword ptr [edi], eax
+ break;
+
+ case OP_BLOCK_COPY:
+ // FIXME: range check
+ EmitString( "56" ); // push esi
+ EmitString( "57" ); // push edi
+ EmitString( "8B 37" ); // mov esi,[edi]
+ EmitString( "8B 7F FC" ); // mov edi,[edi-4]
+ EmitString( "B9" ); // mov ecx,0x12345678
+ Emit4( Constant4() >> 2 );
+ EmitString( "B8" ); // mov eax, datamask
+ Emit4( vm->dataMask );
+ EmitString( "BB" ); // mov ebx, database
+ Emit4( (int)vm->dataBase );
+ EmitString( "23 F0" ); // and esi, eax
+ EmitString( "03 F3" ); // add esi, ebx
+ EmitString( "23 F8" ); // and edi, eax
+ EmitString( "03 FB" ); // add edi, ebx
+ EmitString( "F3 A5" ); // rep movsd
+ EmitString( "5F" ); // pop edi
+ EmitString( "5E" ); // pop esi
+ EmitCommand(LAST_COMMAND_SUB_DI_8); // sub edi, 8
+ break;
+
+ case OP_JUMP:
+ EmitCommand(LAST_COMMAND_SUB_DI_4); // sub edi, 4
+ EmitString( "8B 47 04" ); // mov eax,dword ptr [edi+4]
+ // FIXME: range check
+ EmitString( "FF 24 85" ); // jmp dword ptr [instructionPointers + eax * 4]
+ Emit4( (int)vm->instructionPointers );
+ break;
+ default:
+ Com_Error( ERR_DROP, "VM_CompileX86: bad opcode %i at offset %i", op, pc );
+ }
+ pop0 = pop1;
+ pop1 = op;
+ }
+ }
+
+ // copy to an exact size buffer on the hunk
+ vm->codeLength = compiledOfs;
+ vm->codeBase = Hunk_Alloc( compiledOfs, h_low );
+ Com_Memcpy( vm->codeBase, buf, compiledOfs );
+ Z_Free( buf );
+ Z_Free( jused );
+ Com_Printf( "VM file %s compiled to %i bytes of code\n", vm->name, compiledOfs );
+
+ // offset all the instruction pointers for the new location
+ for ( i = 0 ; i < header->instructionCount ; i++ ) {
+ vm->instructionPointers[i] += (int)vm->codeBase;
+ }
+
+#if 0 // ndef _WIN32
+ // Must make the newly generated code executable
+ {
+ int r;
+ unsigned long addr;
+ int psize = getpagesize();
+
+ addr = ((int)vm->codeBase & ~(psize-1)) - psize;
+
+ r = mprotect((char*)addr, vm->codeLength + (int)vm->codeBase - addr + psize,
+ PROT_READ | PROT_WRITE | PROT_EXEC );
+
+ if (r < 0)
+ Com_Error( ERR_FATAL, "mprotect failed to change PROT_EXEC" );
+ }
+#endif
+
+}
+
+/*
+==============
+VM_CallCompiled
+
+This function is called directly by the generated code
+==============
+*/
+int VM_CallCompiled( vm_t *vm, int *args ) {
+ int stack[1024];
+ int programCounter;
+ int programStack;
+ int stackOnEntry;
+ byte *image;
+ void *entryPoint;
+ void *opStack;
+ int *oldInstructionPointers;
+
+ oldInstructionPointers = instructionPointers;
+
+ currentVM = vm;
+ instructionPointers = vm->instructionPointers;
+
+ // interpret the code
+ vm->currentlyInterpreting = qtrue;
+
+ callMask = vm->dataMask;
+
+ // we might be called recursively, so this might not be the very top
+ programStack = vm->programStack;
+ stackOnEntry = programStack;
+
+ // set up the stack frame
+ image = vm->dataBase;
+
+ programCounter = 0;
+
+ programStack -= 48;
+
+ *(int *)&image[ programStack + 44] = args[9];
+ *(int *)&image[ programStack + 40] = args[8];
+ *(int *)&image[ programStack + 36] = args[7];
+ *(int *)&image[ programStack + 32] = args[6];
+ *(int *)&image[ programStack + 28] = args[5];
+ *(int *)&image[ programStack + 24] = args[4];
+ *(int *)&image[ programStack + 20] = args[3];
+ *(int *)&image[ programStack + 16] = args[2];
+ *(int *)&image[ programStack + 12] = args[1];
+ *(int *)&image[ programStack + 8 ] = args[0];
+ *(int *)&image[ programStack + 4 ] = 0; // return stack
+ *(int *)&image[ programStack ] = -1; // will terminate the loop on return
+
+ // off we go into generated code...
+ entryPoint = vm->codeBase;
+ opStack = &stack;
+
+#ifdef _MSC_VER
+ __asm {
+ pushad
+ mov esi, programStack;
+ mov edi, opStack
+ call entryPoint
+ mov programStack, esi
+ mov opStack, edi
+ popad
+ }
+#else
+ {
+ static int memProgramStack;
+ static void *memOpStack;
+ static void *memEntryPoint;
+
+ memProgramStack = programStack;
+ memOpStack = opStack;
+ memEntryPoint = entryPoint;
+
+ __asm__(" pushal \r\n" \
+ " movl %0,%%esi \r\n" \
+ " movl %1,%%edi \r\n" \
+ " call *%2 \r\n" \
+ " movl %%esi,%0 \r\n" \
+ " movl %%edi,%1 \r\n" \
+ " popal \r\n" \
+ : "=m" (memProgramStack), "=m" (memOpStack) \
+ : "m" (memEntryPoint), "m" (memProgramStack), "m" (memOpStack) \
+ : "si", "di" \
+ );
+
+ programStack = memProgramStack;
+ opStack = memOpStack;
+ }
+#endif
+
+ if ( opStack != &stack[1] ) {
+ Com_Error( ERR_DROP, "opStack corrupted in compiled code" );
+ }
+ if ( programStack != stackOnEntry - 48 ) {
+ Com_Error( ERR_DROP, "programStack corrupted in compiled code" );
+ }
+
+ vm->programStack = stackOnEntry;
+
+ // in case we were recursively called by another vm
+ instructionPointers = oldInstructionPointers;
+
+ return *(int *)opStack;
+}