mirror of
https://github.com/UberGames/ioef.git
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1814 lines
44 KiB
C
1814 lines
44 KiB
C
/*
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===========================================================================
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Copyright (C) 1999-2005 Id Software, Inc.
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This file is part of Quake III Arena source code.
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Quake III Arena source code is free software; you can redistribute it
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and/or modify it under the terms of the GNU General Public License as
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published by the Free Software Foundation; either version 2 of the License,
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or (at your option) any later version.
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Quake III Arena source code is distributed in the hope that it will be
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useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with Quake III Arena source code; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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===========================================================================
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*/
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// vm_x86.c -- load time compiler and execution environment for x86
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#include "vm_local.h"
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#ifdef _WIN32
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#include <windows.h>
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#endif
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#ifdef __FreeBSD__
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#include <sys/types.h>
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#endif
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#ifndef _WIN32
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#include <sys/mman.h> // for PROT_ stuff
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#endif
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/* need this on NX enabled systems (i386 with PAE kernel or
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* noexec32=on x86_64) */
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#if defined(__linux__) || defined(__FreeBSD__)
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#define VM_X86_MMAP
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#endif
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static void VM_Destroy_Compiled(vm_t* self);
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/*
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eax scratch
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ebx/bl opStack offset
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ecx scratch (required for shifts)
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edx scratch (required for divisions)
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esi program stack
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edi opStack base
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x86_64:
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r8 vm->instructionPointers
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r9 vm->dataBase
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*/
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#define VMFREE_BUFFERS() do {Z_Free(buf); Z_Free(jused);} while(0)
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static byte *buf = NULL;
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static byte *jused = NULL;
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static int jusedSize = 0;
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static int compiledOfs = 0;
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static byte *code = NULL;
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static int pc = 0;
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#define FTOL_PTR
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static int instruction, pass;
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static int lastConst = 0;
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static int oc0, oc1, pop0, pop1;
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static int jlabel;
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typedef enum
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{
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LAST_COMMAND_NONE = 0,
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LAST_COMMAND_MOV_STACK_EAX,
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LAST_COMMAND_SUB_BL_1,
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LAST_COMMAND_SUB_BL_2,
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} ELastCommand;
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typedef enum
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{
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VM_JMP_VIOLATION = 0,
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VM_BLOCK_COPY = 1
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} ESysCallType;
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static ELastCommand LastCommand;
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static int iss8(int32_t v)
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{
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return (SCHAR_MIN <= v && v <= SCHAR_MAX);
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}
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#if 0
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static int isu8(uint32_t v)
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{
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return (v <= UCHAR_MAX);
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}
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#endif
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static int NextConstant4(void)
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{
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return (code[pc] | (code[pc+1]<<8) | (code[pc+2]<<16) | (code[pc+3]<<24));
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}
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static int Constant4( void ) {
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int v;
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v = NextConstant4();
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pc += 4;
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return v;
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}
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static int Constant1( void ) {
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int v;
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v = code[pc];
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pc += 1;
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return v;
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}
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static void Emit1( int v )
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{
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buf[ compiledOfs ] = v;
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compiledOfs++;
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LastCommand = LAST_COMMAND_NONE;
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}
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static void Emit2(int v)
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{
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Emit1(v & 255);
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Emit1((v >> 8) & 255);
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}
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static void Emit4(int v)
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{
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Emit1(v & 0xFF);
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Emit1((v >> 8) & 0xFF);
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Emit1((v >> 16) & 0xFF);
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Emit1((v >> 24) & 0xFF);
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}
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static void EmitPtr(void *ptr)
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{
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intptr_t v = (intptr_t) ptr;
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Emit4(v);
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#if idx64
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Emit1((v >> 32) & 0xFF);
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Emit1((v >> 40) & 0xFF);
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Emit1((v >> 48) & 0xFF);
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Emit1((v >> 56) & 0xFF);
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#endif
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}
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static int Hex( int c ) {
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if ( c >= 'a' && c <= 'f' ) {
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return 10 + c - 'a';
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}
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if ( c >= 'A' && c <= 'F' ) {
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return 10 + c - 'A';
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}
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if ( c >= '0' && c <= '9' ) {
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return c - '0';
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}
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VMFREE_BUFFERS();
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Com_Error( ERR_DROP, "Hex: bad char '%c'", c );
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return 0;
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}
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static void EmitString( const char *string ) {
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int c1, c2;
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int v;
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while ( 1 ) {
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c1 = string[0];
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c2 = string[1];
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v = ( Hex( c1 ) << 4 ) | Hex( c2 );
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Emit1( v );
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if ( !string[2] ) {
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break;
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}
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string += 3;
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}
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}
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static void EmitRexString(byte rex, const char *string)
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{
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#if idx64
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if(rex)
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Emit1(rex);
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#endif
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EmitString(string);
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}
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#define MASK_REG(modrm, mask) \
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EmitString("81"); \
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EmitString((modrm)); \
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Emit4((mask))
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// add bl, bytes
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#define STACK_PUSH(bytes) \
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EmitString("80 C3"); \
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Emit1(bytes)
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// sub bl, bytes
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#define STACK_POP(bytes) \
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EmitString("80 EB"); \
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Emit1(bytes)
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static void EmitCommand(ELastCommand command)
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{
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switch(command)
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{
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case LAST_COMMAND_MOV_STACK_EAX:
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EmitString("89 04 9F"); // mov dword ptr [edi + ebx * 4], eax
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break;
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case LAST_COMMAND_SUB_BL_1:
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STACK_POP(1); // sub bl, 1
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break;
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case LAST_COMMAND_SUB_BL_2:
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STACK_POP(2); // sub bl, 2
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break;
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default:
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break;
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}
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LastCommand = command;
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}
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static void EmitPushStack(vm_t *vm)
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{
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if (!jlabel)
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{
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if(LastCommand == LAST_COMMAND_SUB_BL_1)
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{ // sub bl, 1
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compiledOfs -= 3;
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vm->instructionPointers[instruction - 1] = compiledOfs;
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return;
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}
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if(LastCommand == LAST_COMMAND_SUB_BL_2)
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{ // sub bl, 2
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compiledOfs -= 3;
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vm->instructionPointers[instruction - 1] = compiledOfs;
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STACK_POP(1); // sub bl, 1
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return;
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}
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}
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STACK_PUSH(1); // add bl, 1
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}
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static void EmitMovEAXStack(vm_t *vm, int andit)
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{
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if(!jlabel)
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{
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if(LastCommand == LAST_COMMAND_MOV_STACK_EAX)
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{ // mov [edi + ebx * 4], eax
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compiledOfs -= 3;
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vm->instructionPointers[instruction - 1] = compiledOfs;
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}
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else if(pop1 == OP_CONST && buf[compiledOfs-7] == 0xC7 && buf[compiledOfs-6] == 0x04 && buf[compiledOfs - 5] == 0x9F)
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{ // mov [edi + ebx * 4], 0x12345678
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compiledOfs -= 7;
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vm->instructionPointers[instruction - 1] = compiledOfs;
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EmitString("B8"); // mov eax, 0x12345678
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if(andit)
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Emit4(lastConst & andit);
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else
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Emit4(lastConst);
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return;
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}
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else if(pop1 != OP_DIVI && pop1 != OP_DIVU && pop1 != OP_MULI && pop1 != OP_MULU &&
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pop1 != OP_STORE4 && pop1 != OP_STORE2 && pop1 != OP_STORE1)
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{
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EmitString("8B 04 9F"); // mov eax, dword ptr [edi + ebx * 4]
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}
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}
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else
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EmitString("8B 04 9F"); // mov eax, dword ptr [edi + ebx * 4]
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if(andit)
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{
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EmitString("25"); // and eax, 0x12345678
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Emit4(andit);
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}
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}
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void EmitMovECXStack(vm_t *vm)
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{
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if(!jlabel)
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{
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if(LastCommand == LAST_COMMAND_MOV_STACK_EAX) // mov [edi + ebx * 4], eax
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{
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compiledOfs -= 3;
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vm->instructionPointers[instruction - 1] = compiledOfs;
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EmitString("89 C1"); // mov ecx, eax
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return;
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}
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if(pop1 == OP_DIVI || pop1 == OP_DIVU || pop1 == OP_MULI || pop1 == OP_MULU ||
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pop1 == OP_STORE4 || pop1 == OP_STORE2 || pop1 == OP_STORE1)
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{
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EmitString("89 C1"); // mov ecx, eax
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return;
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}
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}
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EmitString("8B 0C 9F"); // mov ecx, dword ptr [edi + ebx * 4]
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}
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void EmitMovEDXStack(vm_t *vm, int andit)
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{
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if(!jlabel)
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{
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if(LastCommand == LAST_COMMAND_MOV_STACK_EAX)
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{ // mov dword ptr [edi + ebx * 4], eax
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compiledOfs -= 3;
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vm->instructionPointers[instruction - 1] = compiledOfs;
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EmitString("8B D0"); // mov edx, eax
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}
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else if(pop1 == OP_DIVI || pop1 == OP_DIVU || pop1 == OP_MULI || pop1 == OP_MULU ||
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pop1 == OP_STORE4 || pop1 == OP_STORE2 || pop1 == OP_STORE1)
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{
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EmitString("8B D0"); // mov edx, eax
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}
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else if(pop1 == OP_CONST && buf[compiledOfs-7] == 0xC7 && buf[compiledOfs-6] == 0x07 && buf[compiledOfs - 5] == 0x9F)
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{ // mov dword ptr [edi + ebx * 4], 0x12345678
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compiledOfs -= 7;
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vm->instructionPointers[instruction - 1] = compiledOfs;
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EmitString("BA"); // mov edx, 0x12345678
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if(andit)
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Emit4(lastConst & andit);
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else
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Emit4(lastConst);
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return;
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}
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else
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EmitString("8B 14 9F"); // mov edx, dword ptr [edi + ebx * 4]
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}
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else
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EmitString("8B 14 9F"); // mov edx, dword ptr [edi + ebx * 4]
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if(andit)
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MASK_REG("E2", andit); // and edx, 0x12345678
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}
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#define JUSED(x) \
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do { \
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if (x < 0 || x >= vm->instructionCount) { \
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VMFREE_BUFFERS(); \
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Com_Error( ERR_DROP, \
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"VM_CompileX86: jump target out of range at offset %d", pc ); \
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} \
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jused[x] = 1; \
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} while(0)
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#define SET_JMPOFS(x) do { buf[(x)] = compiledOfs - ((x) + 1); } while(0)
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/*
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=================
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ErrJump
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Error handler for jump/call to invalid instruction number
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=================
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*/
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static void ErrJump(void)
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{
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Com_Error(ERR_DROP, "program tried to execute code outside VM");
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exit(1);
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}
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/*
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=================
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DoSyscall
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Uses asm to retrieve arguments from registers to work around different calling conventions
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=================
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*/
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#if defined(_MSC_VER) && idx64
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extern void qsyscall64(void);
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extern uint8_t qvmcall64(int *programStack, int *opStack, intptr_t *instructionPointers, byte *dataBase);
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// Microsoft does not support inline assembler on x64 platforms. Meh.
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void DoSyscall(int syscallNum, int programStack, int *opStackBase, uint8_t opStackOfs, intptr_t arg)
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{
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#else
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static void DoSyscall(void)
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{
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int syscallNum;
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int programStack;
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int *opStackBase;
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uint8_t opStackOfs;
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intptr_t arg;
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#endif
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vm_t *savedVM;
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#if defined(_MSC_VER)
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#if !idx64
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__asm
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{
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mov dword ptr syscallNum, eax
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mov dword ptr programStack, esi
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mov byte ptr opStackOfs, bl
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mov dword ptr opStackBase, edi
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mov dword ptr arg, ecx
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}
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#endif
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#else
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__asm__ volatile(
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""
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: "=a" (syscallNum), "=S" (programStack), "=D" (opStackBase), "=b" (opStackOfs),
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"=c" (arg)
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);
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#endif
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// save currentVM so as to allow for recursive VM entry
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savedVM = currentVM;
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// modify VM stack pointer for recursive VM entry
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currentVM->programStack = programStack - 4;
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if(syscallNum < 0)
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{
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int *data;
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#if idx64
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int index;
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intptr_t args[16];
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#endif
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data = (int *) (savedVM->dataBase + programStack + 4);
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#if idx64
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args[0] = ~syscallNum;
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for(index = 1; index < ARRAY_LEN(args); index++)
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args[index] = data[index];
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opStackBase[opStackOfs + 1] = savedVM->systemCall(args);
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#else
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data[0] = ~syscallNum;
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opStackBase[opStackOfs + 1] = savedVM->systemCall((intptr_t *) data);
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#endif
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}
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else
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{
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switch(syscallNum)
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{
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case VM_JMP_VIOLATION:
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ErrJump();
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break;
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case VM_BLOCK_COPY:
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if(opStackOfs < 1)
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Com_Error(ERR_DROP, "VM_BLOCK_COPY failed due to corrupted opStack");
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VM_BlockCopy(opStackBase[(opStackOfs - 1)], opStackBase[opStackOfs], arg);
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break;
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default:
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Com_Error(ERR_DROP, "Unknown VM operation %d", syscallNum);
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break;
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}
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}
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currentVM = savedVM;
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}
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/*
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=================
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EmitCallRel
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Relative call to vm->codeBase + callOfs
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=================
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*/
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void EmitCallRel(vm_t *vm, int callOfs)
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{
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EmitString("E8"); // call 0x12345678
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Emit4(callOfs - compiledOfs - 4);
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}
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/*
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=================
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EmitCallDoSyscall
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Call to DoSyscall()
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=================
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*/
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int EmitCallDoSyscall(vm_t *vm)
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{
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// use edx register to store DoSyscall address
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#if defined(_MSC_VER) && idx64
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EmitRexString(0x48, "BA"); // mov edx, qsyscall64
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EmitPtr(qsyscall64);
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#else
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EmitRexString(0x48, "BA"); // mov edx, DoSyscall
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EmitPtr(DoSyscall);
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#endif
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// Push important registers to stack as we can't really make
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// any assumptions about calling conventions.
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|
EmitString("51"); // push ebx
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EmitString("56"); // push esi
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EmitString("57"); // push edi
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|
#if idx64
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|
EmitRexString(0x41, "50"); // push r8
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EmitRexString(0x41, "51"); // push r9
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|
#endif
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// align the stack pointer to a 16-byte-boundary
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|
EmitString("55"); // push ebp
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|
EmitRexString(0x48, "89 E5"); // mov ebp, esp
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|
EmitRexString(0x48, "83 E4 F0"); // and esp, 0xFFFFFFF0
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// call the syscall wrapper function DoSyscall()
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EmitString("FF D2"); // call edx
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// reset the stack pointer to its previous value
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|
EmitRexString(0x48, "89 EC"); // mov esp, ebp
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EmitString("5D"); // pop ebp
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#if idx64
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|
EmitRexString(0x41, "59"); // pop r9
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EmitRexString(0x41, "58"); // pop r8
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|
#endif
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EmitString("5F"); // pop edi
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EmitString("5E"); // pop esi
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EmitString("59"); // pop ebx
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|
EmitString("C3"); // ret
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return compiledOfs;
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}
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|
|
|
/*
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|
=================
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|
EmitCallErrJump
|
|
Emit the code that triggers execution of the jump violation handler
|
|
=================
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|
*/
|
|
|
|
static void EmitCallErrJump(vm_t *vm, int sysCallOfs)
|
|
{
|
|
EmitString("B8"); // mov eax, 0x12345678
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|
Emit4(VM_JMP_VIOLATION);
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|
|
EmitCallRel(vm, sysCallOfs);
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|
}
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|
|
|
/*
|
|
=================
|
|
EmitCallProcedure
|
|
VM OP_CALL procedure for call destinations obtained at runtime
|
|
=================
|
|
*/
|
|
|
|
int EmitCallProcedure(vm_t *vm, int sysCallOfs)
|
|
{
|
|
int jmpSystemCall, jmpBadAddr;
|
|
int retval;
|
|
|
|
EmitString("8B 04 9F"); // mov eax, dword ptr [edi + ebx * 4]
|
|
STACK_POP(1); // sub bl, 1
|
|
EmitString("85 C0"); // test eax, eax
|
|
|
|
// Jump to syscall code, 1 byte offset should suffice
|
|
EmitString("7C"); // jl systemCall
|
|
jmpSystemCall = compiledOfs++;
|
|
|
|
/************ Call inside VM ************/
|
|
|
|
EmitString("81 F8"); // cmp eax, vm->instructionCount
|
|
Emit4(vm->instructionCount);
|
|
|
|
// Error jump if invalid jump target
|
|
EmitString("73"); // jae badAddr
|
|
jmpBadAddr = compiledOfs++;
|
|
|
|
#if idx64
|
|
EmitRexString(0x49, "FF 14 C0"); // call qword ptr [r8 + eax * 8]
|
|
#else
|
|
EmitString("FF 14 85"); // call dword ptr [vm->instructionPointers + eax * 4]
|
|
Emit4((intptr_t) vm->instructionPointers);
|
|
#endif
|
|
EmitString("8B 04 9F"); // mov eax, dword ptr [edi + ebx * 4]
|
|
EmitString("C3"); // ret
|
|
|
|
// badAddr:
|
|
SET_JMPOFS(jmpBadAddr);
|
|
EmitCallErrJump(vm, sysCallOfs);
|
|
|
|
/************ System Call ************/
|
|
|
|
// systemCall:
|
|
SET_JMPOFS(jmpSystemCall);
|
|
retval = compiledOfs;
|
|
|
|
EmitCallRel(vm, sysCallOfs);
|
|
|
|
// have opStack reg point at return value
|
|
STACK_PUSH(1); // add bl, 1
|
|
EmitString("C3"); // ret
|
|
|
|
return retval;
|
|
}
|
|
|
|
/*
|
|
=================
|
|
EmitJumpIns
|
|
Jump to constant instruction number
|
|
=================
|
|
*/
|
|
|
|
void EmitJumpIns(vm_t *vm, const char *jmpop, int cdest)
|
|
{
|
|
JUSED(cdest);
|
|
|
|
EmitString(jmpop); // j??? 0x12345678
|
|
|
|
// we only know all the jump addresses in the third pass
|
|
if(pass == 2)
|
|
Emit4(vm->instructionPointers[cdest] - compiledOfs - 4);
|
|
else
|
|
compiledOfs += 4;
|
|
}
|
|
|
|
/*
|
|
=================
|
|
EmitCallIns
|
|
Call to constant instruction number
|
|
=================
|
|
*/
|
|
|
|
void EmitCallIns(vm_t *vm, int cdest)
|
|
{
|
|
JUSED(cdest);
|
|
|
|
EmitString("E8"); // call 0x12345678
|
|
|
|
// we only know all the jump addresses in the third pass
|
|
if(pass == 2)
|
|
Emit4(vm->instructionPointers[cdest] - compiledOfs - 4);
|
|
else
|
|
compiledOfs += 4;
|
|
}
|
|
|
|
/*
|
|
=================
|
|
EmitCallConst
|
|
Call to constant instruction number or syscall
|
|
=================
|
|
*/
|
|
|
|
void EmitCallConst(vm_t *vm, int cdest, int callProcOfsSyscall)
|
|
{
|
|
if(cdest < 0)
|
|
{
|
|
EmitString("B8"); // mov eax, cdest
|
|
Emit4(cdest);
|
|
|
|
EmitCallRel(vm, callProcOfsSyscall);
|
|
}
|
|
else
|
|
EmitCallIns(vm, cdest);
|
|
}
|
|
|
|
/*
|
|
=================
|
|
EmitBranchConditions
|
|
Emits x86 branch condition as given in op
|
|
=================
|
|
*/
|
|
void EmitBranchConditions(vm_t *vm, int op)
|
|
{
|
|
switch(op)
|
|
{
|
|
case OP_EQ:
|
|
EmitJumpIns(vm, "0F 84", Constant4()); // je 0x12345678
|
|
break;
|
|
case OP_NE:
|
|
EmitJumpIns(vm, "0F 85", Constant4()); // jne 0x12345678
|
|
break;
|
|
case OP_LTI:
|
|
EmitJumpIns(vm, "0F 8C", Constant4()); // jl 0x12345678
|
|
break;
|
|
case OP_LEI:
|
|
EmitJumpIns(vm, "0F 8E", Constant4()); // jle 0x12345678
|
|
break;
|
|
case OP_GTI:
|
|
EmitJumpIns(vm, "0F 8F", Constant4()); // jg 0x12345678
|
|
break;
|
|
case OP_GEI:
|
|
EmitJumpIns(vm, "0F 8D", Constant4()); // jge 0x12345678
|
|
break;
|
|
case OP_LTU:
|
|
EmitJumpIns(vm, "0F 82", Constant4()); // jb 0x12345678
|
|
break;
|
|
case OP_LEU:
|
|
EmitJumpIns(vm, "0F 86", Constant4()); // jbe 0x12345678
|
|
break;
|
|
case OP_GTU:
|
|
EmitJumpIns(vm, "0F 87", Constant4()); // ja 0x12345678
|
|
break;
|
|
case OP_GEU:
|
|
EmitJumpIns(vm, "0F 83", Constant4()); // jae 0x12345678
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
=================
|
|
ConstOptimize
|
|
Constant values for immediately following instructions may be translated to immediate values
|
|
instead of opStack operations, which will save expensive operations on memory
|
|
=================
|
|
*/
|
|
|
|
qboolean ConstOptimize(vm_t *vm, int callProcOfsSyscall)
|
|
{
|
|
int v;
|
|
int op1;
|
|
|
|
// we can safely perform optimizations only in case if
|
|
// we are 100% sure that next instruction is not a jump label
|
|
if (vm->jumpTableTargets && !jused[instruction])
|
|
op1 = code[pc+4];
|
|
else
|
|
return qfalse;
|
|
|
|
switch ( op1 ) {
|
|
|
|
case OP_LOAD4:
|
|
EmitPushStack(vm);
|
|
#if idx64
|
|
EmitRexString(0x41, "8B 81"); // mov eax, dword ptr [r9 + 0x12345678]
|
|
Emit4(Constant4() & vm->dataMask);
|
|
#else
|
|
EmitString("B8"); // mov eax, 0x12345678
|
|
EmitPtr(vm->dataBase + (Constant4() & vm->dataMask));
|
|
EmitString("8B 00"); // mov eax, dword ptr [eax]
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
|
|
pc++; // OP_LOAD4
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_LOAD2:
|
|
EmitPushStack(vm);
|
|
#if idx64
|
|
EmitRexString(0x41, "0F B7 81"); // movzx eax, word ptr [r9 + 0x12345678]
|
|
Emit4(Constant4() & vm->dataMask);
|
|
#else
|
|
EmitString("B8"); // mov eax, 0x12345678
|
|
EmitPtr(vm->dataBase + (Constant4() & vm->dataMask));
|
|
EmitString("0F B7 00"); // movzx eax, word ptr [eax]
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
|
|
pc++; // OP_LOAD2
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_LOAD1:
|
|
EmitPushStack(vm);
|
|
#if idx64
|
|
EmitRexString(0x41, "0F B6 81"); // movzx eax, byte ptr [r9 + 0x12345678]
|
|
Emit4(Constant4() & vm->dataMask);
|
|
#else
|
|
EmitString("B8"); // mov eax, 0x12345678
|
|
EmitPtr(vm->dataBase + (Constant4() & vm->dataMask));
|
|
EmitString("0F B6 00"); // movzx eax, byte ptr [eax]
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
|
|
pc++; // OP_LOAD1
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_STORE4:
|
|
EmitMovEAXStack(vm, (vm->dataMask & ~3));
|
|
#if idx64
|
|
EmitRexString(0x41, "C7 04 01"); // mov dword ptr [r9 + eax], 0x12345678
|
|
Emit4(Constant4());
|
|
#else
|
|
EmitString("C7 80"); // mov dword ptr [eax + 0x12345678], 0x12345678
|
|
Emit4((intptr_t) vm->dataBase);
|
|
Emit4(Constant4());
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
pc++; // OP_STORE4
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_STORE2:
|
|
EmitMovEAXStack(vm, (vm->dataMask & ~1));
|
|
#if idx64
|
|
Emit1(0x66); // mov word ptr [r9 + eax], 0x1234
|
|
EmitRexString(0x41, "C7 04 01");
|
|
Emit2(Constant4());
|
|
#else
|
|
EmitString("66 C7 80"); // mov word ptr [eax + 0x12345678], 0x1234
|
|
Emit4((intptr_t) vm->dataBase);
|
|
Emit2(Constant4());
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
|
|
pc++; // OP_STORE2
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_STORE1:
|
|
EmitMovEAXStack(vm, vm->dataMask);
|
|
#if idx64
|
|
EmitRexString(0x41, "C6 04 01"); // mov byte [r9 + eax], 0x12
|
|
Emit1(Constant4());
|
|
#else
|
|
EmitString("C6 80"); // mov byte ptr [eax + 0x12345678], 0x12
|
|
Emit4((intptr_t) vm->dataBase);
|
|
Emit1(Constant4());
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
|
|
pc++; // OP_STORE1
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_ADD:
|
|
v = Constant4();
|
|
|
|
EmitMovEAXStack(vm, 0);
|
|
if(iss8(v))
|
|
{
|
|
EmitString("83 C0"); // add eax, 0x7F
|
|
Emit1(v);
|
|
}
|
|
else
|
|
{
|
|
EmitString("05"); // add eax, 0x12345678
|
|
Emit4(v);
|
|
}
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX);
|
|
|
|
pc++; // OP_ADD
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_SUB:
|
|
v = Constant4();
|
|
|
|
EmitMovEAXStack(vm, 0);
|
|
if(iss8(v))
|
|
{
|
|
EmitString("83 E8"); // sub eax, 0x7F
|
|
Emit1(v);
|
|
}
|
|
else
|
|
{
|
|
EmitString("2D"); // sub eax, 0x12345678
|
|
Emit4(v);
|
|
}
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX);
|
|
|
|
pc++; // OP_SUB
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_MULI:
|
|
v = Constant4();
|
|
|
|
EmitMovEAXStack(vm, 0);
|
|
if(iss8(v))
|
|
{
|
|
EmitString("6B C0"); // imul eax, 0x7F
|
|
Emit1(v);
|
|
}
|
|
else
|
|
{
|
|
EmitString("69 C0"); // imul eax, 0x12345678
|
|
Emit4(v);
|
|
}
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX);
|
|
pc++; // OP_MULI
|
|
instruction += 1;
|
|
|
|
return qtrue;
|
|
|
|
case OP_LSH:
|
|
v = NextConstant4();
|
|
if(v < 0 || v > 31)
|
|
break;
|
|
|
|
EmitMovEAXStack(vm, 0);
|
|
EmitString("C1 E0"); // shl eax, 0x12
|
|
Emit1(v);
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX);
|
|
|
|
pc += 5; // CONST + OP_LSH
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_RSHI:
|
|
v = NextConstant4();
|
|
if(v < 0 || v > 31)
|
|
break;
|
|
|
|
EmitMovEAXStack(vm, 0);
|
|
EmitString("C1 F8"); // sar eax, 0x12
|
|
Emit1(v);
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX);
|
|
|
|
pc += 5; // CONST + OP_RSHI
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_RSHU:
|
|
v = NextConstant4();
|
|
if(v < 0 || v > 31)
|
|
break;
|
|
|
|
EmitMovEAXStack(vm, 0);
|
|
EmitString("C1 E8"); // shr eax, 0x12
|
|
Emit1(v);
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX);
|
|
|
|
pc += 5; // CONST + OP_RSHU
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_BAND:
|
|
v = Constant4();
|
|
|
|
EmitMovEAXStack(vm, 0);
|
|
if(iss8(v))
|
|
{
|
|
EmitString("83 E0"); // and eax, 0x7F
|
|
Emit1(v);
|
|
}
|
|
else
|
|
{
|
|
EmitString("25"); // and eax, 0x12345678
|
|
Emit4(v);
|
|
}
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX);
|
|
|
|
pc += 1; // OP_BAND
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_BOR:
|
|
v = Constant4();
|
|
|
|
EmitMovEAXStack(vm, 0);
|
|
if(iss8(v))
|
|
{
|
|
EmitString("83 C8"); // or eax, 0x7F
|
|
Emit1(v);
|
|
}
|
|
else
|
|
{
|
|
EmitString("0D"); // or eax, 0x12345678
|
|
Emit4(v);
|
|
}
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX);
|
|
|
|
pc += 1; // OP_BOR
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_BXOR:
|
|
v = Constant4();
|
|
|
|
EmitMovEAXStack(vm, 0);
|
|
if(iss8(v))
|
|
{
|
|
EmitString("83 F0"); // xor eax, 0x7F
|
|
Emit1(v);
|
|
}
|
|
else
|
|
{
|
|
EmitString("35"); // xor eax, 0x12345678
|
|
Emit4(v);
|
|
}
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX);
|
|
|
|
pc += 1; // OP_BXOR
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_EQ:
|
|
case OP_NE:
|
|
case OP_LTI:
|
|
case OP_LEI:
|
|
case OP_GTI:
|
|
case OP_GEI:
|
|
case OP_LTU:
|
|
case OP_LEU:
|
|
case OP_GTU:
|
|
case OP_GEU:
|
|
EmitMovEAXStack(vm, 0);
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1);
|
|
EmitString("3D"); // cmp eax, 0x12345678
|
|
Emit4(Constant4());
|
|
|
|
pc++; // OP_*
|
|
EmitBranchConditions(vm, op1);
|
|
instruction++;
|
|
|
|
return qtrue;
|
|
|
|
case OP_EQF:
|
|
case OP_NEF:
|
|
if(NextConstant4())
|
|
break;
|
|
pc += 5; // CONST + OP_EQF|OP_NEF
|
|
|
|
EmitMovEAXStack(vm, 0);
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1);
|
|
// floating point hack :)
|
|
EmitString("25"); // and eax, 0x7FFFFFFF
|
|
Emit4(0x7FFFFFFF);
|
|
if(op1 == OP_EQF)
|
|
EmitJumpIns(vm, "0F 84", Constant4()); // jz 0x12345678
|
|
else
|
|
EmitJumpIns(vm, "0F 85", Constant4()); // jnz 0x12345678
|
|
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
|
|
case OP_JUMP:
|
|
EmitJumpIns(vm, "E9", Constant4()); // jmp 0x12345678
|
|
|
|
pc += 1; // OP_JUMP
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
case OP_CALL:
|
|
v = Constant4();
|
|
EmitCallConst(vm, v, callProcOfsSyscall);
|
|
|
|
pc += 1; // OP_CALL
|
|
instruction += 1;
|
|
return qtrue;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return qfalse;
|
|
}
|
|
|
|
/*
|
|
=================
|
|
VM_Compile
|
|
=================
|
|
*/
|
|
void VM_Compile(vm_t *vm, vmHeader_t *header)
|
|
{
|
|
int op;
|
|
int maxLength;
|
|
int v;
|
|
int i;
|
|
int callProcOfsSyscall, callProcOfs, callDoSyscallOfs;
|
|
|
|
jusedSize = header->instructionCount + 2;
|
|
|
|
// allocate a very large temp buffer, we will shrink it later
|
|
maxLength = header->codeLength * 8 + 64;
|
|
buf = Z_Malloc(maxLength);
|
|
jused = Z_Malloc(jusedSize);
|
|
code = Z_Malloc(header->codeLength+32);
|
|
|
|
Com_Memset(jused, 0, jusedSize);
|
|
Com_Memset(buf, 0, maxLength);
|
|
|
|
// copy code in larger buffer and put some zeros at the end
|
|
// so we can safely look ahead for a few instructions in it
|
|
// without a chance to get false-positive because of some garbage bytes
|
|
Com_Memset(code, 0, header->codeLength+32);
|
|
Com_Memcpy(code, (byte *)header + header->codeOffset, header->codeLength );
|
|
|
|
// 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;
|
|
}
|
|
|
|
// Start buffer with x86-VM specific procedures
|
|
compiledOfs = 0;
|
|
|
|
callDoSyscallOfs = compiledOfs;
|
|
callProcOfs = EmitCallDoSyscall(vm);
|
|
callProcOfsSyscall = EmitCallProcedure(vm, callDoSyscallOfs);
|
|
vm->entryOfs = compiledOfs;
|
|
|
|
for(pass=0; pass < 3; pass++) {
|
|
oc0 = -23423;
|
|
oc1 = -234354;
|
|
pop0 = -43435;
|
|
pop1 = -545455;
|
|
|
|
// translate all instructions
|
|
pc = 0;
|
|
instruction = 0;
|
|
//code = (byte *)header + header->codeOffset;
|
|
compiledOfs = vm->entryOfs;
|
|
|
|
LastCommand = LAST_COMMAND_NONE;
|
|
|
|
while(instruction < header->instructionCount)
|
|
{
|
|
if(compiledOfs > maxLength - 16)
|
|
{
|
|
VMFREE_BUFFERS();
|
|
Com_Error(ERR_DROP, "VM_CompileX86: maxLength exceeded");
|
|
}
|
|
|
|
vm->instructionPointers[ instruction ] = compiledOfs;
|
|
|
|
if ( !vm->jumpTableTargets )
|
|
jlabel = 1;
|
|
else
|
|
jlabel = jused[ instruction ];
|
|
|
|
instruction++;
|
|
|
|
if(pc > header->codeLength)
|
|
{
|
|
VMFREE_BUFFERS();
|
|
Com_Error(ERR_DROP, "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(ConstOptimize(vm, callProcOfsSyscall))
|
|
break;
|
|
|
|
EmitPushStack(vm);
|
|
EmitString("C7 04 9F"); // mov dword ptr [edi + ebx * 4], 0x12345678
|
|
lastConst = Constant4();
|
|
|
|
Emit4(lastConst);
|
|
if(code[pc] == OP_JUMP)
|
|
JUSED(lastConst);
|
|
|
|
break;
|
|
case OP_LOCAL:
|
|
EmitPushStack(vm);
|
|
EmitString("8D 86"); // lea eax, [0x12345678 + esi]
|
|
oc0 = oc1;
|
|
oc1 = Constant4();
|
|
Emit4(oc1);
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
break;
|
|
case OP_ARG:
|
|
EmitMovEAXStack(vm, 0); // mov eax, dword ptr [edi + ebx * 4]
|
|
EmitString("8B D6"); // mov edx, esi
|
|
EmitString("81 C2"); // add edx, 0x12345678
|
|
Emit4((Constant1() & 0xFF));
|
|
MASK_REG("E2", vm->dataMask); // and edx, 0x12345678
|
|
#if idx64
|
|
EmitRexString(0x41, "89 04 11"); // mov dword ptr [r9 + edx], eax
|
|
#else
|
|
EmitString("89 82"); // mov dword ptr [edx + 0x12345678], eax
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_CALL:
|
|
EmitCallRel(vm, callProcOfs);
|
|
break;
|
|
case OP_PUSH:
|
|
EmitPushStack(vm);
|
|
break;
|
|
case OP_POP:
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
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 -= 12;
|
|
vm->instructionPointers[instruction - 1] = compiledOfs;
|
|
}
|
|
|
|
pc++; // OP_CONST
|
|
v = Constant4();
|
|
|
|
EmitMovEDXStack(vm, vm->dataMask);
|
|
if(v == 1 && oc0 == oc1 && pop0 == OP_LOCAL && pop1 == OP_LOCAL)
|
|
{
|
|
#if idx64
|
|
EmitRexString(0x41, "FF 04 11"); // inc dword ptr [r9 + edx]
|
|
#else
|
|
EmitString("FF 82"); // inc dword ptr [edx + 0x12345678]
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
#if idx64
|
|
EmitRexString(0x41, "8B 04 11"); // mov eax, dword ptr [r9 + edx]
|
|
#else
|
|
EmitString("8B 82"); // mov eax, dword ptr [edx + 0x12345678]
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
EmitString("05"); // add eax, v
|
|
Emit4(v);
|
|
|
|
if (oc0 == oc1 && pop0 == OP_LOCAL && pop1 == OP_LOCAL)
|
|
{
|
|
#if idx64
|
|
EmitRexString(0x41, "89 04 11"); // mov dword ptr [r9 + edx], eax
|
|
#else
|
|
EmitString("89 82"); // mov dword ptr [edx + 0x12345678], eax
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
EmitString("8B 14 9F"); // mov edx, dword ptr [edi + ebx * 4]
|
|
MASK_REG("E2", vm->dataMask); // and edx, 0x12345678
|
|
#if idx64
|
|
EmitRexString(0x41, "89 04 11"); // mov dword ptr [r9 + edx], eax
|
|
#else
|
|
EmitString("89 82"); // mov dword ptr [edx + 0x12345678], eax
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
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 -= 12;
|
|
vm->instructionPointers[instruction - 1] = compiledOfs;
|
|
}
|
|
|
|
pc++; // OP_CONST
|
|
v = Constant4();
|
|
|
|
EmitMovEDXStack(vm, vm->dataMask);
|
|
if(v == 1 && oc0 == oc1 && pop0 == OP_LOCAL && pop1 == OP_LOCAL)
|
|
{
|
|
#if idx64
|
|
EmitRexString(0x41, "FF 0C 11"); // dec dword ptr [r9 + edx]
|
|
#else
|
|
EmitString("FF 8A"); // dec dword ptr [edx + 0x12345678]
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
#if idx64
|
|
EmitRexString(0x41, "8B 04 11"); // mov eax, dword ptr [r9 + edx]
|
|
#else
|
|
EmitString("8B 82"); // mov eax, dword ptr [edx + 0x12345678]
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
EmitString("2D"); // sub eax, v
|
|
Emit4(v);
|
|
|
|
if(oc0 == oc1 && pop0 == OP_LOCAL && pop1 == OP_LOCAL)
|
|
{
|
|
#if idx64
|
|
EmitRexString(0x41, "89 04 11"); // mov dword ptr [r9 + edx], eax
|
|
#else
|
|
EmitString("89 82"); // mov dword ptr [edx + 0x12345678], eax
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
EmitString("8B 14 9F"); // mov edx, dword ptr [edi + ebx * 4]
|
|
MASK_REG("E2", vm->dataMask); // and edx, 0x12345678
|
|
#if idx64
|
|
EmitRexString(0x41, "89 04 11"); // mov dword ptr [r9 + edx], eax
|
|
#else
|
|
EmitString("89 82"); // mov dword ptr [edx + 0x12345678], eax
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
}
|
|
}
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
pc++; // OP_SUB
|
|
pc++; // OP_STORE
|
|
instruction += 3;
|
|
break;
|
|
}
|
|
|
|
if(buf[compiledOfs - 3] == 0x89 && buf[compiledOfs - 2] == 0x04 && buf[compiledOfs - 1] == 0x9F)
|
|
{
|
|
compiledOfs -= 3;
|
|
vm->instructionPointers[instruction - 1] = compiledOfs;
|
|
MASK_REG("E0", vm->dataMask); // and eax, 0x12345678
|
|
#if idx64
|
|
EmitRexString(0x41, "8B 04 01"); // mov eax, dword ptr [r9 + eax]
|
|
#else
|
|
EmitString("8B 80"); // mov eax, dword ptr [eax + 0x1234567]
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
break;
|
|
}
|
|
|
|
EmitMovEAXStack(vm, vm->dataMask);
|
|
#if idx64
|
|
EmitRexString(0x41, "8B 04 01"); // mov eax, dword ptr [r9 + eax]
|
|
#else
|
|
EmitString("8B 80"); // mov eax, dword ptr [eax + 0x12345678]
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
break;
|
|
case OP_LOAD2:
|
|
EmitMovEAXStack(vm, vm->dataMask);
|
|
#if idx64
|
|
EmitRexString(0x41, "0F B7 04 01"); // movzx eax, word ptr [r9 + eax]
|
|
#else
|
|
EmitString("0F B7 80"); // movzx eax, word ptr [eax + 0x12345678]
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
break;
|
|
case OP_LOAD1:
|
|
EmitMovEAXStack(vm, vm->dataMask);
|
|
#if idx64
|
|
EmitRexString(0x41, "0F B6 04 01"); // movzx eax, byte ptr [r9 + eax]
|
|
#else
|
|
EmitString("0F B6 80"); // movzx eax, byte ptr [eax + 0x12345678]
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
break;
|
|
case OP_STORE4:
|
|
EmitMovEAXStack(vm, 0);
|
|
EmitString("8B 54 9F FC"); // mov edx, dword ptr -4[edi + ebx * 4]
|
|
MASK_REG("E2", vm->dataMask & ~3); // and edx, 0x12345678
|
|
#if idx64
|
|
EmitRexString(0x41, "89 04 11"); // mov dword ptr [r9 + edx], eax
|
|
#else
|
|
EmitString("89 82"); // mov dword ptr [edx + 0x12345678], eax
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_SUB_BL_2); // sub bl, 2
|
|
break;
|
|
case OP_STORE2:
|
|
EmitMovEAXStack(vm, 0);
|
|
EmitString("8B 54 9F FC"); // mov edx, dword ptr -4[edi + ebx * 4]
|
|
MASK_REG("E2", vm->dataMask & ~1); // and edx, 0x12345678
|
|
#if idx64
|
|
Emit1(0x66); // mov word ptr [r9 + edx], eax
|
|
EmitRexString(0x41, "89 04 11");
|
|
#else
|
|
EmitString("66 89 82"); // mov word ptr [edx + 0x12345678], eax
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_SUB_BL_2); // sub bl, 2
|
|
break;
|
|
case OP_STORE1:
|
|
EmitMovEAXStack(vm, 0);
|
|
EmitString("8B 54 9F FC"); // mov edx, dword ptr -4[edi + ebx * 4]
|
|
MASK_REG("E2", vm->dataMask); // and edx, 0x12345678
|
|
#if idx64
|
|
EmitRexString(0x41, "88 04 11"); // mov byte ptr [r9 + edx], eax
|
|
#else
|
|
EmitString("88 82"); // mov byte ptr [edx + 0x12345678], eax
|
|
Emit4((intptr_t) vm->dataBase);
|
|
#endif
|
|
EmitCommand(LAST_COMMAND_SUB_BL_2); // sub bl, 2
|
|
break;
|
|
|
|
case OP_EQ:
|
|
case OP_NE:
|
|
case OP_LTI:
|
|
case OP_LEI:
|
|
case OP_GTI:
|
|
case OP_GEI:
|
|
case OP_LTU:
|
|
case OP_LEU:
|
|
case OP_GTU:
|
|
case OP_GEU:
|
|
EmitMovEAXStack(vm, 0);
|
|
EmitCommand(LAST_COMMAND_SUB_BL_2); // sub bl, 2
|
|
EmitString("39 44 9F 04"); // cmp eax, dword ptr 4[edi + ebx * 4]
|
|
|
|
EmitBranchConditions(vm, op);
|
|
break;
|
|
case OP_EQF:
|
|
case OP_NEF:
|
|
case OP_LTF:
|
|
case OP_LEF:
|
|
case OP_GTF:
|
|
case OP_GEF:
|
|
EmitCommand(LAST_COMMAND_SUB_BL_2); // sub bl, 2
|
|
EmitString("D9 44 9F 04"); // fld dword ptr 4[edi + ebx * 4]
|
|
EmitString("D8 5C 9F 08"); // fcomp dword ptr 8[edi + ebx * 4]
|
|
EmitString("DF E0"); // fnstsw ax
|
|
|
|
switch(op)
|
|
{
|
|
case OP_EQF:
|
|
EmitString("F6 C4 40"); // test ah,0x40
|
|
EmitJumpIns(vm, "0F 85", Constant4()); // jne 0x12345678
|
|
break;
|
|
case OP_NEF:
|
|
EmitString("F6 C4 40"); // test ah,0x40
|
|
EmitJumpIns(vm, "0F 84", Constant4()); // je 0x12345678
|
|
break;
|
|
case OP_LTF:
|
|
EmitString("F6 C4 01"); // test ah,0x01
|
|
EmitJumpIns(vm, "0F 85", Constant4()); // jne 0x12345678
|
|
break;
|
|
case OP_LEF:
|
|
EmitString("F6 C4 41"); // test ah,0x41
|
|
EmitJumpIns(vm, "0F 85", Constant4()); // jne 0x12345678
|
|
break;
|
|
case OP_GTF:
|
|
EmitString("F6 C4 41"); // test ah,0x41
|
|
EmitJumpIns(vm, "0F 84", Constant4()); // je 0x12345678
|
|
break;
|
|
case OP_GEF:
|
|
EmitString("F6 C4 01"); // test ah,0x01
|
|
EmitJumpIns(vm, "0F 84", Constant4()); // je 0x12345678
|
|
break;
|
|
}
|
|
break;
|
|
case OP_NEGI:
|
|
EmitMovEAXStack(vm, 0);
|
|
EmitString("F7 D8"); // neg eax
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX);
|
|
break;
|
|
case OP_ADD:
|
|
EmitMovEAXStack(vm, 0); // mov eax, dword ptr [edi + ebx * 4]
|
|
EmitString("01 44 9F FC"); // add dword ptr -4[edi + ebx * 4], eax
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_SUB:
|
|
EmitMovEAXStack(vm, 0); // mov eax, dword ptr [edi + ebx * 4]
|
|
EmitString("29 44 9F FC"); // sub dword ptr -4[edi + ebx * 4], eax
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_DIVI:
|
|
EmitString("8B 44 9F FC"); // mov eax,dword ptr -4[edi + ebx * 4]
|
|
EmitString("99"); // cdq
|
|
EmitString("F7 3C 9F"); // idiv dword ptr [edi + ebx * 4]
|
|
EmitString("89 44 9F FC"); // mov dword ptr -4[edi + ebx * 4],eax
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_DIVU:
|
|
EmitString("8B 44 9F FC"); // mov eax,dword ptr -4[edi + ebx * 4]
|
|
EmitString("33 D2"); // xor edx, edx
|
|
EmitString("F7 34 9F"); // div dword ptr [edi + ebx * 4]
|
|
EmitString("89 44 9F FC"); // mov dword ptr -4[edi + ebx * 4],eax
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_MODI:
|
|
EmitString("8B 44 9F FC"); // mov eax,dword ptr -4[edi + ebx * 4]
|
|
EmitString("99" ); // cdq
|
|
EmitString("F7 3C 9F"); // idiv dword ptr [edi + ebx * 4]
|
|
EmitString("89 54 9F FC"); // mov dword ptr -4[edi + ebx * 4],edx
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_MODU:
|
|
EmitString("8B 44 9F FC"); // mov eax,dword ptr -4[edi + ebx * 4]
|
|
EmitString("33 D2"); // xor edx, edx
|
|
EmitString("F7 34 9F"); // div dword ptr [edi + ebx * 4]
|
|
EmitString("89 54 9F FC"); // mov dword ptr -4[edi + ebx * 4],edx
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_MULI:
|
|
EmitString("8B 44 9F FC"); // mov eax,dword ptr -4[edi + ebx * 4]
|
|
EmitString("F7 2C 9F"); // imul dword ptr [edi + ebx * 4]
|
|
EmitString("89 44 9F FC"); // mov dword ptr -4[edi + ebx * 4],eax
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_MULU:
|
|
EmitString("8B 44 9F FC"); // mov eax,dword ptr -4[edi + ebx * 4]
|
|
EmitString("F7 24 9F"); // mul dword ptr [edi + ebx * 4]
|
|
EmitString("89 44 9F FC"); // mov dword ptr -4[edi + ebx * 4],eax
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_BAND:
|
|
EmitMovEAXStack(vm, 0); // mov eax, dword ptr [edi + ebx * 4]
|
|
EmitString("21 44 9F FC"); // and dword ptr -4[edi + ebx * 4],eax
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_BOR:
|
|
EmitMovEAXStack(vm, 0); // mov eax, dword ptr [edi + ebx * 4]
|
|
EmitString("09 44 9F FC"); // or dword ptr -4[edi + ebx * 4],eax
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_BXOR:
|
|
EmitMovEAXStack(vm, 0); // mov eax, dword ptr [edi + ebx * 4]
|
|
EmitString("31 44 9F FC"); // xor dword ptr -4[edi + ebx * 4],eax
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_BCOM:
|
|
EmitString("F7 14 9F"); // not dword ptr [edi + ebx * 4]
|
|
break;
|
|
case OP_LSH:
|
|
EmitMovECXStack(vm);
|
|
EmitString("D3 64 9F FC"); // shl dword ptr -4[edi + ebx * 4], cl
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_RSHI:
|
|
EmitMovECXStack(vm);
|
|
EmitString("D3 7C 9F FC"); // sar dword ptr -4[edi + ebx * 4], cl
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_RSHU:
|
|
EmitMovECXStack(vm);
|
|
EmitString("D3 6C 9F FC"); // shr dword ptr -4[edi + ebx * 4], cl
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_NEGF:
|
|
EmitString("D9 04 9F"); // fld dword ptr [edi + ebx * 4]
|
|
EmitString("D9 E0"); // fchs
|
|
EmitString("D9 1C 9F"); // fstp dword ptr [edi + ebx * 4]
|
|
break;
|
|
case OP_ADDF:
|
|
EmitString("D9 44 9F FC"); // fld dword ptr -4[edi + ebx * 4]
|
|
EmitString("D8 04 9F"); // fadd dword ptr [edi + ebx * 4]
|
|
EmitString("D9 5C 9F FC"); // fstp dword ptr -4[edi + ebx * 4]
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
break;
|
|
case OP_SUBF:
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
EmitString("D9 04 9F"); // fld dword ptr [edi + ebx * 4]
|
|
EmitString("D8 64 9F 04"); // fsub dword ptr 4[edi + ebx * 4]
|
|
EmitString("D9 1C 9F"); // fstp dword ptr [edi + ebx * 4]
|
|
break;
|
|
case OP_DIVF:
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
EmitString("D9 04 9F"); // fld dword ptr [edi + ebx * 4]
|
|
EmitString("D8 74 9F 04"); // fdiv dword ptr 4[edi + ebx * 4]
|
|
EmitString("D9 1C 9F"); // fstp dword ptr [edi + ebx * 4]
|
|
break;
|
|
case OP_MULF:
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
EmitString("D9 04 9F"); // fld dword ptr [edi + ebx * 4]
|
|
EmitString("D8 4C 9F 04"); // fmul dword ptr 4[edi + ebx * 4]
|
|
EmitString("D9 1C 9F"); // fstp dword ptr [edi + ebx * 4]
|
|
break;
|
|
case OP_CVIF:
|
|
EmitString("DB 04 9F"); // fild dword ptr [edi + ebx * 4]
|
|
EmitString("D9 1C 9F"); // fstp dword ptr [edi + ebx * 4]
|
|
break;
|
|
case OP_CVFI:
|
|
#ifndef FTOL_PTR // WHENHELLISFROZENOVER
|
|
// not IEEE complient, but simple and fast
|
|
EmitString("D9 04 9F"); // fld dword ptr [edi + ebx * 4]
|
|
EmitString("DB 1C 9F"); // fistp dword ptr [edi + ebx * 4]
|
|
#else // FTOL_PTR
|
|
// call the library conversion function
|
|
EmitRexString(0x48, "BA"); // mov edx, Q_VMftol
|
|
EmitPtr(Q_VMftol);
|
|
EmitRexString(0x48, "FF D2"); // call edx
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
#endif
|
|
break;
|
|
case OP_SEX8:
|
|
EmitString("0F BE 04 9F"); // movsx eax, byte ptr [edi + ebx * 4]
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
break;
|
|
case OP_SEX16:
|
|
EmitString("0F BF 04 9F"); // movsx eax, word ptr [edi + ebx * 4]
|
|
EmitCommand(LAST_COMMAND_MOV_STACK_EAX); // mov dword ptr [edi + ebx * 4], eax
|
|
break;
|
|
|
|
case OP_BLOCK_COPY:
|
|
EmitString("B8"); // mov eax, 0x12345678
|
|
Emit4(VM_BLOCK_COPY);
|
|
EmitString("B9"); // mov ecx, 0x12345678
|
|
Emit4(Constant4());
|
|
|
|
EmitCallRel(vm, callDoSyscallOfs);
|
|
|
|
EmitCommand(LAST_COMMAND_SUB_BL_2); // sub bl, 2
|
|
break;
|
|
|
|
case OP_JUMP:
|
|
EmitCommand(LAST_COMMAND_SUB_BL_1); // sub bl, 1
|
|
EmitString("8B 44 9F 04"); // mov eax, dword ptr 4[edi + ebx * 4]
|
|
EmitString("81 F8"); // cmp eax, vm->instructionCount
|
|
Emit4(vm->instructionCount);
|
|
#if idx64
|
|
EmitString("73 04"); // jae +4
|
|
EmitRexString(0x49, "FF 24 C0"); // jmp qword ptr [r8 + eax * 8]
|
|
#else
|
|
EmitString("73 07"); // jae +7
|
|
EmitString("FF 24 85"); // jmp dword ptr [instructionPointers + eax * 4]
|
|
Emit4((intptr_t) vm->instructionPointers);
|
|
#endif
|
|
EmitCallErrJump(vm, callDoSyscallOfs);
|
|
break;
|
|
default:
|
|
VMFREE_BUFFERS();
|
|
Com_Error(ERR_DROP, "VM_CompileX86: bad opcode %i at offset %i", op, pc);
|
|
}
|
|
pop0 = pop1;
|
|
pop1 = op;
|
|
}
|
|
}
|
|
|
|
// copy to an exact sized buffer with the appropriate permission bits
|
|
vm->codeLength = compiledOfs;
|
|
#ifdef VM_X86_MMAP
|
|
vm->codeBase = mmap(NULL, compiledOfs, PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, -1, 0);
|
|
if(vm->codeBase == MAP_FAILED)
|
|
Com_Error(ERR_FATAL, "VM_CompileX86: can't mmap memory");
|
|
#elif _WIN32
|
|
// allocate memory with EXECUTE permissions under windows.
|
|
vm->codeBase = VirtualAlloc(NULL, compiledOfs, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
|
|
if(!vm->codeBase)
|
|
Com_Error(ERR_FATAL, "VM_CompileX86: VirtualAlloc failed");
|
|
#else
|
|
vm->codeBase = malloc(compiledOfs);
|
|
if(!vm->codeBase)
|
|
Com_Error(ERR_FATAL, "VM_CompileX86: malloc failed");
|
|
#endif
|
|
|
|
Com_Memcpy( vm->codeBase, buf, compiledOfs );
|
|
|
|
#ifdef VM_X86_MMAP
|
|
if(mprotect(vm->codeBase, compiledOfs, PROT_READ|PROT_EXEC))
|
|
Com_Error(ERR_FATAL, "VM_CompileX86: mprotect failed");
|
|
#elif _WIN32
|
|
{
|
|
DWORD oldProtect = 0;
|
|
|
|
// remove write permissions.
|
|
if(!VirtualProtect(vm->codeBase, compiledOfs, PAGE_EXECUTE_READ, &oldProtect))
|
|
Com_Error(ERR_FATAL, "VM_CompileX86: VirtualProtect failed");
|
|
}
|
|
#endif
|
|
|
|
Z_Free( code );
|
|
Z_Free( buf );
|
|
Z_Free( jused );
|
|
Com_Printf( "VM file %s compiled to %i bytes of code\n", vm->name, compiledOfs );
|
|
|
|
vm->destroy = VM_Destroy_Compiled;
|
|
|
|
// offset all the instruction pointers for the new location
|
|
for ( i = 0 ; i < header->instructionCount ; i++ ) {
|
|
vm->instructionPointers[i] += (intptr_t) vm->codeBase;
|
|
}
|
|
}
|
|
|
|
void VM_Destroy_Compiled(vm_t* self)
|
|
{
|
|
#ifdef VM_X86_MMAP
|
|
munmap(self->codeBase, self->codeLength);
|
|
#elif _WIN32
|
|
VirtualFree(self->codeBase, 0, MEM_RELEASE);
|
|
#else
|
|
free(self->codeBase);
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
==============
|
|
VM_CallCompiled
|
|
|
|
This function is called directly by the generated code
|
|
==============
|
|
*/
|
|
|
|
int VM_CallCompiled(vm_t *vm, int *args)
|
|
{
|
|
byte stack[OPSTACK_SIZE + 15];
|
|
void *entryPoint;
|
|
int programStack, stackOnEntry;
|
|
byte *image;
|
|
int *opStack;
|
|
int opStackOfs;
|
|
|
|
currentVM = vm;
|
|
|
|
// interpret the code
|
|
vm->currentlyInterpreting = qtrue;
|
|
|
|
// we might be called recursively, so this might not be the very top
|
|
programStack = stackOnEntry = vm->programStack;
|
|
|
|
// set up the stack frame
|
|
image = vm->dataBase;
|
|
|
|
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 + vm->entryOfs;
|
|
opStack = PADP(stack, 16);
|
|
*opStack = 0xDEADBEEF;
|
|
opStackOfs = 0;
|
|
|
|
#ifdef _MSC_VER
|
|
#if idx64
|
|
opStackOfs = qvmcall64(&programStack, opStack, vm->instructionPointers, vm->dataBase);
|
|
#else
|
|
__asm
|
|
{
|
|
pushad
|
|
|
|
mov esi, dword ptr programStack
|
|
mov edi, dword ptr opStack
|
|
mov ebx, dword ptr opStackOfs
|
|
|
|
call entryPoint
|
|
|
|
mov dword ptr opStackOfs, ebx
|
|
mov dword ptr opStack, edi
|
|
mov dword ptr programStack, esi
|
|
|
|
popad
|
|
}
|
|
#endif
|
|
#elif idx64
|
|
__asm__ volatile(
|
|
"movq %5, %%rax\n"
|
|
"movq %3, %%r8\n"
|
|
"movq %4, %%r9\n"
|
|
"push %%r15\n"
|
|
"push %%r14\n"
|
|
"push %%r13\n"
|
|
"push %%r12\n"
|
|
"callq *%%rax\n"
|
|
"pop %%r12\n"
|
|
"pop %%r13\n"
|
|
"pop %%r14\n"
|
|
"pop %%r15\n"
|
|
: "+S" (programStack), "+D" (opStack), "+b" (opStackOfs)
|
|
: "g" (vm->instructionPointers), "g" (vm->dataBase), "g" (entryPoint)
|
|
: "cc", "memory", "%rax", "%rcx", "%rdx", "%r8", "%r9", "%r10", "%r11"
|
|
);
|
|
#else
|
|
__asm__ volatile(
|
|
"calll *%3\n"
|
|
: "+S" (programStack), "+D" (opStack), "+b" (opStackOfs)
|
|
: "g" (entryPoint)
|
|
: "cc", "memory", "%eax", "%ecx", "%edx"
|
|
);
|
|
#endif
|
|
|
|
if(opStackOfs != 1 || *opStack != 0xDEADBEEF)
|
|
{
|
|
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;
|
|
|
|
return opStack[opStackOfs];
|
|
}
|