/* =========================================================================== 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 _WIN32 #include <windows.h> #else #ifdef __FreeBSD__ #include <sys/types.h> #endif #include <sys/mman.h> // for PROT_ stuff /* need this on NX enabled systems (i386 with PAE kernel or * noexec32=on x86_64) */ #define VM_X86_MMAP // workaround for systems that use the old MAP_ANON macro #ifndef MAP_ANONYMOUS #define MAP_ANONYMOUS MAP_ANON #endif #endif static void VM_Destroy_Compiled(vm_t* self); /* eax scratch ebx/bl opStack offset ecx scratch (required for shifts) edx scratch (required for divisions) esi program stack edi opStack base x86_64: r8 vm->instructionPointers r9 vm->dataBase */ #define VMFREE_BUFFERS() do {Z_Free(buf); Z_Free(jused);} while(0) static byte *buf = NULL; static byte *jused = NULL; static int jusedSize = 0; static int compiledOfs = 0; static byte *code = NULL; static int pc = 0; #define FTOL_PTR static int instruction, pass; static int lastConst = 0; static int oc0, oc1, pop0, pop1; static int jlabel; typedef enum { LAST_COMMAND_NONE = 0, LAST_COMMAND_MOV_STACK_EAX, LAST_COMMAND_SUB_BL_1, LAST_COMMAND_SUB_BL_2, } ELastCommand; typedef enum { VM_JMP_VIOLATION = 0, VM_BLOCK_COPY = 1 } ESysCallType; static ELastCommand LastCommand; static int iss8(int32_t v) { return (SCHAR_MIN <= v && v <= SCHAR_MAX); } #if 0 static int isu8(uint32_t v) { return (v <= UCHAR_MAX); } #endif static int NextConstant4(void) { return (code[pc] | (code[pc+1]<<8) | (code[pc+2]<<16) | (code[pc+3]<<24)); } static int Constant4( void ) { int v; v = NextConstant4(); 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; } static void Emit2(int v) { Emit1(v & 255); Emit1((v >> 8) & 255); } static void Emit4(int v) { Emit1(v & 0xFF); Emit1((v >> 8) & 0xFF); Emit1((v >> 16) & 0xFF); Emit1((v >> 24) & 0xFF); } static void EmitPtr(void *ptr) { intptr_t v = (intptr_t) ptr; Emit4(v); #if idx64 Emit1((v >> 32) & 0xFF); Emit1((v >> 40) & 0xFF); Emit1((v >> 48) & 0xFF); Emit1((v >> 56) & 0xFF); #endif } 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'; } VMFREE_BUFFERS(); 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 EmitRexString(byte rex, const char *string) { #if idx64 if(rex) Emit1(rex); #endif EmitString(string); } #define MASK_REG(modrm, mask) \ do { \ EmitString("81"); \ EmitString((modrm)); \ Emit4((mask)); \ } while(0) // add bl, bytes #define STACK_PUSH(bytes) \ do { \ EmitString("80 C3"); \ Emit1(bytes); \ } while(0) // sub bl, bytes #define STACK_POP(bytes) \ do { \ EmitString("80 EB"); \ Emit1(bytes); \ } while(0) static void EmitCommand(ELastCommand command) { switch(command) { case LAST_COMMAND_MOV_STACK_EAX: EmitString("89 04 9F"); // mov dword ptr [edi + ebx * 4], eax break; case LAST_COMMAND_SUB_BL_1: STACK_POP(1); // sub bl, 1 break; case LAST_COMMAND_SUB_BL_2: STACK_POP(2); // sub bl, 2 break; default: break; } LastCommand = command; } static void EmitPushStack(vm_t *vm) { if (!jlabel) { if(LastCommand == LAST_COMMAND_SUB_BL_1) { // sub bl, 1 compiledOfs -= 3; vm->instructionPointers[instruction - 1] = compiledOfs; return; } if(LastCommand == LAST_COMMAND_SUB_BL_2) { // sub bl, 2 compiledOfs -= 3; vm->instructionPointers[instruction - 1] = compiledOfs; STACK_POP(1); // sub bl, 1 return; } } STACK_PUSH(1); // add bl, 1 } static void EmitMovEAXStack(vm_t *vm, int andit) { if(!jlabel) { if(LastCommand == LAST_COMMAND_MOV_STACK_EAX) { // mov [edi + ebx * 4], eax compiledOfs -= 3; vm->instructionPointers[instruction - 1] = compiledOfs; } else if(pop1 == OP_CONST && buf[compiledOfs-7] == 0xC7 && buf[compiledOfs-6] == 0x04 && buf[compiledOfs - 5] == 0x9F) { // mov [edi + ebx * 4], 0x12345678 compiledOfs -= 7; vm->instructionPointers[instruction - 1] = compiledOfs; EmitString("B8"); // mov eax, 0x12345678 if(andit) Emit4(lastConst & andit); else Emit4(lastConst); return; } else if(pop1 != OP_DIVI && pop1 != OP_DIVU && pop1 != OP_MULI && pop1 != OP_MULU && pop1 != OP_STORE4 && pop1 != OP_STORE2 && pop1 != OP_STORE1) { EmitString("8B 04 9F"); // mov eax, dword ptr [edi + ebx * 4] } } else EmitString("8B 04 9F"); // mov eax, dword ptr [edi + ebx * 4] if(andit) { EmitString("25"); // and eax, 0x12345678 Emit4(andit); } } void EmitMovECXStack(vm_t *vm) { if(!jlabel) { if(LastCommand == LAST_COMMAND_MOV_STACK_EAX) // mov [edi + ebx * 4], eax { compiledOfs -= 3; vm->instructionPointers[instruction - 1] = compiledOfs; EmitString("89 C1"); // mov ecx, eax return; } if(pop1 == OP_DIVI || pop1 == OP_DIVU || pop1 == OP_MULI || pop1 == OP_MULU || pop1 == OP_STORE4 || pop1 == OP_STORE2 || pop1 == OP_STORE1) { EmitString("89 C1"); // mov ecx, eax return; } } EmitString("8B 0C 9F"); // mov ecx, dword ptr [edi + ebx * 4] } void EmitMovEDXStack(vm_t *vm, int andit) { if(!jlabel) { if(LastCommand == LAST_COMMAND_MOV_STACK_EAX) { // mov dword ptr [edi + ebx * 4], eax compiledOfs -= 3; vm->instructionPointers[instruction - 1] = compiledOfs; EmitString("8B D0"); // mov edx, eax } else if(pop1 == OP_DIVI || pop1 == OP_DIVU || pop1 == OP_MULI || pop1 == OP_MULU || pop1 == OP_STORE4 || pop1 == OP_STORE2 || pop1 == OP_STORE1) { EmitString("8B D0"); // mov edx, eax } else if(pop1 == OP_CONST && buf[compiledOfs-7] == 0xC7 && buf[compiledOfs-6] == 0x07 && buf[compiledOfs - 5] == 0x9F) { // mov dword ptr [edi + ebx * 4], 0x12345678 compiledOfs -= 7; vm->instructionPointers[instruction - 1] = compiledOfs; EmitString("BA"); // mov edx, 0x12345678 if(andit) Emit4(lastConst & andit); else Emit4(lastConst); return; } else EmitString("8B 14 9F"); // mov edx, dword ptr [edi + ebx * 4] } else EmitString("8B 14 9F"); // mov edx, dword ptr [edi + ebx * 4] if(andit) MASK_REG("E2", andit); // and edx, 0x12345678 } #define JUSED(x) \ do { \ if (x < 0 || x >= vm->instructionCount) { \ VMFREE_BUFFERS(); \ Com_Error( ERR_DROP, \ "VM_CompileX86: jump target out of range at offset %d", pc ); \ } \ jused[x] = 1; \ } while(0) #define SET_JMPOFS(x) do { buf[(x)] = compiledOfs - ((x) + 1); } while(0) /* ================= ErrJump Error handler for jump/call to invalid instruction number ================= */ static void __attribute__((__noreturn__)) ErrJump(void) { Com_Error(ERR_DROP, "program tried to execute code outside VM"); } /* ================= DoSyscall Assembler helper routines will write its arguments directly to global variables so as to work around different calling conventions ================= */ int vm_syscallNum; int vm_programStack; int *vm_opStackBase; uint8_t vm_opStackOfs; intptr_t vm_arg; static void DoSyscall(void) { vm_t *savedVM; // save currentVM so as to allow for recursive VM entry savedVM = currentVM; // modify VM stack pointer for recursive VM entry currentVM->programStack = vm_programStack - 4; if(vm_syscallNum < 0) { int *data, *ret; #if idx64 int index; intptr_t args[MAX_VMSYSCALL_ARGS]; #endif data = (int *) (savedVM->dataBase + vm_programStack + 4); ret = &vm_opStackBase[vm_opStackOfs + 1]; #if idx64 args[0] = ~vm_syscallNum; for(index = 1; index < ARRAY_LEN(args); index++) args[index] = data[index]; *ret = savedVM->systemCall(args); #else data[0] = ~vm_syscallNum; *ret = savedVM->systemCall((intptr_t *) data); #endif } else { switch(vm_syscallNum) { case VM_JMP_VIOLATION: ErrJump(); break; case VM_BLOCK_COPY: if(vm_opStackOfs < 1) Com_Error(ERR_DROP, "VM_BLOCK_COPY failed due to corrupted opStack"); VM_BlockCopy(vm_opStackBase[(vm_opStackOfs - 1)], vm_opStackBase[vm_opStackOfs], vm_arg); break; default: Com_Error(ERR_DROP, "Unknown VM operation %d", vm_syscallNum); break; } } currentVM = savedVM; } /* ================= EmitCallRel Relative call to vm->codeBase + callOfs ================= */ void EmitCallRel(vm_t *vm, int callOfs) { EmitString("E8"); // call 0x12345678 Emit4(callOfs - compiledOfs - 4); } /* ================= EmitCallDoSyscall Call to DoSyscall() ================= */ int EmitCallDoSyscall(vm_t *vm) { // use edx register to store DoSyscall address EmitRexString(0x48, "BA"); // mov edx, DoSyscall EmitPtr(DoSyscall); // Push important registers to stack as we can't really make // any assumptions about calling conventions. EmitString("51"); // push ebx EmitString("56"); // push esi EmitString("57"); // push edi #if idx64 EmitRexString(0x41, "50"); // push r8 EmitRexString(0x41, "51"); // push r9 #endif // write arguments to global vars // syscall number EmitString("A3"); // mov [0x12345678], eax EmitPtr(&vm_syscallNum); // vm_programStack value EmitString("89 F0"); // mov eax, esi EmitString("A3"); // mov [0x12345678], eax EmitPtr(&vm_programStack); // vm_opStackOfs EmitString("88 D8"); // mov al, bl EmitString("A2"); // mov [0x12345678], al EmitPtr(&vm_opStackOfs); // vm_opStackBase EmitRexString(0x48, "89 F8"); // mov eax, edi EmitRexString(0x48, "A3"); // mov [0x12345678], eax EmitPtr(&vm_opStackBase); // vm_arg EmitString("89 C8"); // mov eax, ecx EmitString("A3"); // mov [0x12345678], eax EmitPtr(&vm_arg); // align the stack pointer to a 16-byte-boundary EmitString("55"); // push ebp EmitRexString(0x48, "89 E5"); // mov ebp, esp EmitRexString(0x48, "83 E4 F0"); // and esp, 0xFFFFFFF0 // call the syscall wrapper function DoSyscall() EmitString("FF D2"); // call edx // reset the stack pointer to its previous value EmitRexString(0x48, "89 EC"); // mov esp, ebp EmitString("5D"); // pop ebp #if idx64 EmitRexString(0x41, "59"); // pop r9 EmitRexString(0x41, "58"); // pop r8 #endif EmitString("5F"); // pop edi EmitString("5E"); // pop esi EmitString("59"); // pop ebx EmitString("C3"); // ret return compiledOfs; } /* ================= EmitCallErrJump Emit the code that triggers execution of the jump violation handler ================= */ static void EmitCallErrJump(vm_t *vm, int sysCallOfs) { EmitString("B8"); // mov eax, 0x12345678 Emit4(VM_JMP_VIOLATION); EmitCallRel(vm, sysCallOfs); } /* ================= 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 pc = -1; // a bogus value to be printed in out-of-bounds error messages for( i = 0; i < vm->numJumpTableTargets; i++ ) { JUSED( *(int *)(vm->jumpTableTargets + ( i * sizeof( int ) ) ) ); } // 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 ============== */ #if defined(_MSC_VER) && defined(idx64) extern uint8_t qvmcall64(int *programStack, int *opStack, intptr_t *instructionPointers, byte *dataBase); #endif int VM_CallCompiled(vm_t *vm, int *args) { byte stack[OPSTACK_SIZE + 15]; void *entryPoint; int programStack, stackOnEntry; byte *image; int *opStack; int opStackOfs; int arg; 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 -= ( 8 + 4 * MAX_VMMAIN_ARGS ); for ( arg = 0; arg < MAX_VMMAIN_ARGS; arg++ ) *(int *)&image[ programStack + 8 + arg * 4 ] = args[ arg ]; *(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 - (8 + 4 * MAX_VMMAIN_ARGS)) Com_Error(ERR_DROP, "programStack corrupted in compiled code"); vm->programStack = stackOnEntry; return opStack[opStackOfs]; }