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Diffstat (limited to 'src/qcommon/vm.c')
| -rw-r--r-- | src/qcommon/vm.c | 895 |
1 files changed, 895 insertions, 0 deletions
diff --git a/src/qcommon/vm.c b/src/qcommon/vm.c new file mode 100644 index 0000000..0017b41 --- /dev/null +++ b/src/qcommon/vm.c @@ -0,0 +1,895 @@ +/* +=========================================================================== +Copyright (C) 1999-2005 Id Software, Inc. +Copyright (C) 2000-2006 Tim Angus + +This file is part of Tremulous. + +Tremulous 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. + +Tremulous 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 Tremulous; if not, write to the Free Software +Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +=========================================================================== +*/ +// vm.c -- virtual machine + +/* + + +intermix code and data +symbol table + +a dll has one imported function: VM_SystemCall +and one exported function: Perform + + +*/ + +#include "vm_local.h" + + +vm_t *currentVM = NULL; // bk001212 +vm_t *lastVM = NULL; // bk001212 +int vm_debugLevel; + +#define MAX_VM 3 +vm_t vmTable[MAX_VM]; + + +void VM_VmInfo_f( void ); +void VM_VmProfile_f( void ); + + + +#if 0 // 64bit! +// converts a VM pointer to a C pointer and +// checks to make sure that the range is acceptable +void *VM_VM2C( vmptr_t p, int length ) { + return (void *)p; +} +#endif + +void VM_Debug( int level ) { + vm_debugLevel = level; +} + +/* +============== +VM_Init +============== +*/ +void VM_Init( void ) { + Cvar_Get( "vm_cgame", "2", CVAR_ARCHIVE ); // !@# SHIP WITH SET TO 2 + Cvar_Get( "vm_game", "2", CVAR_ARCHIVE ); // !@# SHIP WITH SET TO 2 + Cvar_Get( "vm_ui", "2", CVAR_ARCHIVE ); // !@# SHIP WITH SET TO 2 + + Cmd_AddCommand ("vmprofile", VM_VmProfile_f ); + Cmd_AddCommand ("vminfo", VM_VmInfo_f ); + + Com_Memset( vmTable, 0, sizeof( vmTable ) ); +} + + +/* +=============== +VM_ValueToSymbol + +Assumes a program counter value +=============== +*/ +const char *VM_ValueToSymbol( vm_t *vm, int value ) { + vmSymbol_t *sym; + static char text[MAX_TOKEN_CHARS]; + + sym = vm->symbols; + if ( !sym ) { + return "NO SYMBOLS"; + } + + // find the symbol + while ( sym->next && sym->next->symValue <= value ) { + sym = sym->next; + } + + if ( value == sym->symValue ) { + return sym->symName; + } + + Com_sprintf( text, sizeof( text ), "%s+%i", sym->symName, value - sym->symValue ); + + return text; +} + +/* +=============== +VM_ValueToFunctionSymbol + +For profiling, find the symbol behind this value +=============== +*/ +vmSymbol_t *VM_ValueToFunctionSymbol( vm_t *vm, int value ) { + vmSymbol_t *sym; + static vmSymbol_t nullSym; + + sym = vm->symbols; + if ( !sym ) { + return &nullSym; + } + + while ( sym->next && sym->next->symValue <= value ) { + sym = sym->next; + } + + return sym; +} + + +/* +=============== +VM_SymbolToValue +=============== +*/ +int VM_SymbolToValue( vm_t *vm, const char *symbol ) { + vmSymbol_t *sym; + + for ( sym = vm->symbols ; sym ; sym = sym->next ) { + if ( !strcmp( symbol, sym->symName ) ) { + return sym->symValue; + } + } + return 0; +} + + +/* +===================== +VM_SymbolForCompiledPointer +===================== +*/ +#if 0 // 64bit! +const char *VM_SymbolForCompiledPointer( vm_t *vm, void *code ) { + int i; + + if ( code < (void *)vm->codeBase ) { + return "Before code block"; + } + if ( code >= (void *)(vm->codeBase + vm->codeLength) ) { + return "After code block"; + } + + // find which original instruction it is after + for ( i = 0 ; i < vm->codeLength ; i++ ) { + if ( (void *)vm->instructionPointers[i] > code ) { + break; + } + } + i--; + + // now look up the bytecode instruction pointer + return VM_ValueToSymbol( vm, i ); +} +#endif + + + +/* +=============== +ParseHex +=============== +*/ +int ParseHex( const char *text ) { + int value; + int c; + + value = 0; + while ( ( c = *text++ ) != 0 ) { + if ( c >= '0' && c <= '9' ) { + value = value * 16 + c - '0'; + continue; + } + if ( c >= 'a' && c <= 'f' ) { + value = value * 16 + 10 + c - 'a'; + continue; + } + if ( c >= 'A' && c <= 'F' ) { + value = value * 16 + 10 + c - 'A'; + continue; + } + } + + return value; +} + +/* +=============== +VM_LoadSymbols +=============== +*/ +void VM_LoadSymbols( vm_t *vm ) { + int len; + char *mapfile, *text_p, *token; + char name[MAX_QPATH]; + char symbols[MAX_QPATH]; + vmSymbol_t **prev, *sym; + int count; + int value; + int chars; + int segment; + int numInstructions; + + // don't load symbols if not developer + if ( !com_developer->integer ) { + return; + } + + COM_StripExtension(vm->name, name, sizeof(name)); + Com_sprintf( symbols, sizeof( symbols ), "vm/%s.map", name ); + len = FS_ReadFile( symbols, (void **)&mapfile ); + if ( !mapfile ) { + Com_Printf( "Couldn't load symbol file: %s\n", symbols ); + return; + } + + numInstructions = vm->instructionPointersLength >> 2; + + // parse the symbols + text_p = mapfile; + prev = &vm->symbols; + count = 0; + + while ( 1 ) { + token = COM_Parse( &text_p ); + if ( !token[0] ) { + break; + } + segment = ParseHex( token ); + if ( segment ) { + COM_Parse( &text_p ); + COM_Parse( &text_p ); + continue; // only load code segment values + } + + token = COM_Parse( &text_p ); + if ( !token[0] ) { + Com_Printf( "WARNING: incomplete line at end of file\n" ); + break; + } + value = ParseHex( token ); + + token = COM_Parse( &text_p ); + if ( !token[0] ) { + Com_Printf( "WARNING: incomplete line at end of file\n" ); + break; + } + chars = strlen( token ); + sym = Hunk_Alloc( sizeof( *sym ) + chars, h_high ); + *prev = sym; + prev = &sym->next; + sym->next = NULL; + + // convert value from an instruction number to a code offset + if ( value >= 0 && value < numInstructions ) { + value = vm->instructionPointers[value]; + } + + sym->symValue = value; + Q_strncpyz( sym->symName, token, chars + 1 ); + + count++; + } + + vm->numSymbols = count; + Com_Printf( "%i symbols parsed from %s\n", count, symbols ); + FS_FreeFile( mapfile ); +} + +/* +============ +VM_DllSyscall + +Dlls will call this directly + + rcg010206 The horror; the horror. + + The syscall mechanism relies on stack manipulation to get it's args. + This is likely due to C's inability to pass "..." parameters to + a function in one clean chunk. On PowerPC Linux, these parameters + are not necessarily passed on the stack, so while (&arg[0] == arg) + is true, (&arg[1] == 2nd function parameter) is not necessarily + accurate, as arg's value might have been stored to the stack or + other piece of scratch memory to give it a valid address, but the + next parameter might still be sitting in a register. + + Quake's syscall system also assumes that the stack grows downward, + and that any needed types can be squeezed, safely, into a signed int. + + This hack below copies all needed values for an argument to a + array in memory, so that Quake can get the correct values. This can + also be used on systems where the stack grows upwards, as the + presumably standard and safe stdargs.h macros are used. + + As for having enough space in a signed int for your datatypes, well, + it might be better to wait for DOOM 3 before you start porting. :) + + The original code, while probably still inherently dangerous, seems + to work well enough for the platforms it already works on. Rather + than add the performance hit for those platforms, the original code + is still in use there. + + For speed, we just grab 15 arguments, and don't worry about exactly + how many the syscall actually needs; the extra is thrown away. + +============ +*/ +intptr_t QDECL VM_DllSyscall( intptr_t arg, ... ) { +#if !id386 + // rcg010206 - see commentary above + intptr_t args[16]; + int i; + va_list ap; + + args[0] = arg; + + va_start(ap, arg); + for (i = 1; i < sizeof (args) / sizeof (args[i]); i++) + args[i] = va_arg(ap, intptr_t); + va_end(ap); + + return currentVM->systemCall( args ); +#else // original id code + return currentVM->systemCall( &arg ); +#endif +} + +/* +================= +VM_LoadQVM + +Load a .qvm file +================= +*/ +vmHeader_t *VM_LoadQVM( vm_t *vm, qboolean alloc ) { + int length; + int dataLength; + int i; + char filename[MAX_QPATH]; + vmHeader_t *header; + + // load the image + Com_sprintf( filename, sizeof(filename), "vm/%s.qvm", vm->name ); + Com_Printf( "Loading vm file %s...\n", filename ); + length = FS_ReadFile( filename, (void **)&header ); + if ( !header ) { + Com_Printf( "Failed.\n" ); + VM_Free( vm ); + return NULL; + } + + if( LittleLong( header->vmMagic ) == VM_MAGIC_VER2 ) { + Com_Printf( "...which has vmMagic VM_MAGIC_VER2\n" ); + + // byte swap the header + for ( i = 0 ; i < sizeof( vmHeader_t ) / 4 ; i++ ) { + ((int *)header)[i] = LittleLong( ((int *)header)[i] ); + } + + // validate + if ( header->jtrgLength < 0 + || header->bssLength < 0 + || header->dataLength < 0 + || header->litLength < 0 + || header->codeLength <= 0 ) { + VM_Free( vm ); + Com_Error( ERR_FATAL, "%s has bad header", filename ); + } + } else if( LittleLong( header->vmMagic ) == VM_MAGIC ) { + // byte swap the header + // sizeof( vmHeader_t ) - sizeof( int ) is the 1.32b vm header size + for ( i = 0 ; i < ( sizeof( vmHeader_t ) - sizeof( int ) ) / 4 ; i++ ) { + ((int *)header)[i] = LittleLong( ((int *)header)[i] ); + } + + // validate + if ( header->bssLength < 0 + || header->dataLength < 0 + || header->litLength < 0 + || header->codeLength <= 0 ) { + VM_Free( vm ); + Com_Error( ERR_FATAL, "%s has bad header", filename ); + } + } else { + VM_Free( vm ); + Com_Error( ERR_FATAL, "%s does not have a recognisable " + "magic number in its header", filename ); + } + + // round up to next power of 2 so all data operations can + // be mask protected + dataLength = header->dataLength + header->litLength + header->bssLength; + for ( i = 0 ; dataLength > ( 1 << i ) ; i++ ) { + } + dataLength = 1 << i; + + if( alloc ) { + // allocate zero filled space for initialized and uninitialized data + vm->dataBase = Hunk_Alloc( dataLength, h_high ); + vm->dataMask = dataLength - 1; + } else { + // clear the data + Com_Memset( vm->dataBase, 0, dataLength ); + } + + // copy the intialized data + Com_Memcpy( vm->dataBase, (byte *)header + header->dataOffset, header->dataLength + header->litLength ); + + // byte swap the longs + for ( i = 0 ; i < header->dataLength ; i += 4 ) { + *(int *)(vm->dataBase + i) = LittleLong( *(int *)(vm->dataBase + i ) ); + } + + if( header->vmMagic == VM_MAGIC_VER2 ) { + vm->numJumpTableTargets = header->jtrgLength >> 2; + Com_Printf( "Loading %d jump table targets\n", vm->numJumpTableTargets ); + + if( alloc ) { + vm->jumpTableTargets = Hunk_Alloc( header->jtrgLength, h_high ); + } else { + Com_Memset( vm->jumpTableTargets, 0, header->jtrgLength ); + } + + Com_Memcpy( vm->jumpTableTargets, (byte *)header + header->dataOffset + + header->dataLength + header->litLength, header->jtrgLength ); + + // byte swap the longs + for ( i = 0 ; i < header->jtrgLength ; i += 4 ) { + *(int *)(vm->jumpTableTargets + i) = LittleLong( *(int *)(vm->jumpTableTargets + i ) ); + } + } + + return header; +} + +/* +================= +VM_Restart + +Reload the data, but leave everything else in place +This allows a server to do a map_restart without changing memory allocation +================= +*/ +vm_t *VM_Restart( vm_t *vm ) { + vmHeader_t *header; + + // DLL's can't be restarted in place + if ( vm->dllHandle ) { + char name[MAX_QPATH]; + intptr_t (*systemCall)( intptr_t *parms ); + + systemCall = vm->systemCall; + Q_strncpyz( name, vm->name, sizeof( name ) ); + + VM_Free( vm ); + + vm = VM_Create( name, systemCall, VMI_NATIVE ); + return vm; + } + + // load the image + Com_Printf( "VM_Restart()\n" ); + + if( !( header = VM_LoadQVM( vm, qfalse ) ) ) { + Com_Error( ERR_DROP, "VM_Restart failed.\n" ); + return NULL; + } + + // free the original file + FS_FreeFile( header ); + + return vm; +} + +/* +================ +VM_Create + +If image ends in .qvm it will be interpreted, otherwise +it will attempt to load as a system dll +================ +*/ + +#define STACK_SIZE 0x20000 + +vm_t *VM_Create( const char *module, intptr_t (*systemCalls)(intptr_t *), + vmInterpret_t interpret ) { + vm_t *vm; + vmHeader_t *header; + int i, remaining; + + if ( !module || !module[0] || !systemCalls ) { + Com_Error( ERR_FATAL, "VM_Create: bad parms" ); + } + + remaining = Hunk_MemoryRemaining(); + + // see if we already have the VM + for ( i = 0 ; i < MAX_VM ; i++ ) { + if (!Q_stricmp(vmTable[i].name, module)) { + vm = &vmTable[i]; + return vm; + } + } + + // find a free vm + for ( i = 0 ; i < MAX_VM ; i++ ) { + if ( !vmTable[i].name[0] ) { + break; + } + } + + if ( i == MAX_VM ) { + Com_Error( ERR_FATAL, "VM_Create: no free vm_t" ); + } + + vm = &vmTable[i]; + + Q_strncpyz( vm->name, module, sizeof( vm->name ) ); + vm->systemCall = systemCalls; + + // never allow dll loading with a demo + if ( interpret == VMI_NATIVE ) { + if ( Cvar_VariableValue( "fs_restrict" ) ) { + interpret = VMI_COMPILED; + } + } + + if ( interpret == VMI_NATIVE ) { + // try to load as a system dll + Com_Printf( "Loading dll file %s.\n", vm->name ); + vm->dllHandle = Sys_LoadDll( module, vm->fqpath , &vm->entryPoint, VM_DllSyscall ); + if ( vm->dllHandle ) { + return vm; + } + + Com_Printf( "Failed to load dll, looking for qvm.\n" ); + interpret = VMI_COMPILED; + } + + // load the image + if( !( header = VM_LoadQVM( vm, qtrue ) ) ) { + return NULL; + } + + // allocate space for the jump targets, which will be filled in by the compile/prep functions + vm->instructionPointersLength = header->instructionCount * 4; + vm->instructionPointers = Hunk_Alloc( vm->instructionPointersLength, h_high ); + + // copy or compile the instructions + vm->codeLength = header->codeLength; + + vm->compiled = qfalse; + +#ifdef NO_VM_COMPILED + if(interpret >= VMI_COMPILED) { + Com_Printf("Architecture doesn't have a bytecode compiler, using interpreter\n"); + interpret = VMI_BYTECODE; + } +#else + if ( interpret >= VMI_COMPILED ) { + vm->compiled = qtrue; + VM_Compile( vm, header ); + } +#endif + // VM_Compile may have reset vm->compiled if compilation failed + if (!vm->compiled) + { + VM_PrepareInterpreter( vm, header ); + } + + // free the original file + FS_FreeFile( header ); + + // load the map file + VM_LoadSymbols( vm ); + + // the stack is implicitly at the end of the image + vm->programStack = vm->dataMask + 1; + vm->stackBottom = vm->programStack - STACK_SIZE; + + Com_Printf("%s loaded in %d bytes on the hunk\n", module, remaining - Hunk_MemoryRemaining()); + + return vm; +} + +/* +============== +VM_Free +============== +*/ +void VM_Free( vm_t *vm ) { + + if(vm->destroy) + vm->destroy(vm); + + if ( vm->dllHandle ) { + Sys_UnloadDll( vm->dllHandle ); + Com_Memset( vm, 0, sizeof( *vm ) ); + } +#if 0 // now automatically freed by hunk + if ( vm->codeBase ) { + Z_Free( vm->codeBase ); + } + if ( vm->dataBase ) { + Z_Free( vm->dataBase ); + } + if ( vm->instructionPointers ) { + Z_Free( vm->instructionPointers ); + } +#endif + Com_Memset( vm, 0, sizeof( *vm ) ); + + currentVM = NULL; + lastVM = NULL; +} + +void VM_Clear(void) { + int i; + for (i=0;i<MAX_VM; i++) { + if ( vmTable[i].dllHandle ) { + Sys_UnloadDll( vmTable[i].dllHandle ); + } + Com_Memset( &vmTable[i], 0, sizeof( vm_t ) ); + } + currentVM = NULL; + lastVM = NULL; +} + +void *VM_ArgPtr( intptr_t intValue ) { + if ( !intValue ) { + return NULL; + } + // bk001220 - currentVM is missing on reconnect + if ( currentVM==NULL ) + return NULL; + + if ( currentVM->entryPoint ) { + return (void *)(currentVM->dataBase + intValue); + } + else { + return (void *)(currentVM->dataBase + (intValue & currentVM->dataMask)); + } +} + +void *VM_ExplicitArgPtr( vm_t *vm, intptr_t intValue ) { + if ( !intValue ) { + return NULL; + } + + // bk010124 - currentVM is missing on reconnect here as well? + if ( currentVM==NULL ) + return NULL; + + // + if ( vm->entryPoint ) { + return (void *)(vm->dataBase + intValue); + } + else { + return (void *)(vm->dataBase + (intValue & vm->dataMask)); + } +} + + +/* +============== +VM_Call + + +Upon a system call, the stack will look like: + +sp+32 parm1 +sp+28 parm0 +sp+24 return value +sp+20 return address +sp+16 local1 +sp+14 local0 +sp+12 arg1 +sp+8 arg0 +sp+4 return stack +sp return address + +An interpreted function will immediately execute +an OP_ENTER instruction, which will subtract space for +locals from sp +============== +*/ +#define MAX_STACK 256 +#define STACK_MASK (MAX_STACK-1) + +intptr_t QDECL VM_Call( vm_t *vm, int callnum, ... ) { + vm_t *oldVM; + intptr_t r; + int i; + + if ( !vm ) { + Com_Error( ERR_FATAL, "VM_Call with NULL vm" ); + } + + oldVM = currentVM; + currentVM = vm; + lastVM = vm; + + if ( vm_debugLevel ) { + Com_Printf( "VM_Call( %d )\n", callnum ); + } + + // if we have a dll loaded, call it directly + if ( vm->entryPoint ) { + //rcg010207 - see dissertation at top of VM_DllSyscall() in this file. + int args[10]; + va_list ap; + va_start(ap, callnum); + for (i = 0; i < sizeof (args) / sizeof (args[i]); i++) { + args[i] = va_arg(ap, int); + } + va_end(ap); + + r = vm->entryPoint( callnum, args[0], args[1], args[2], args[3], + args[4], args[5], args[6], args[7], + args[8], args[9]); + } else { +#if id386 // i386 calling convention doesn't need conversion +#ifndef NO_VM_COMPILED + if ( vm->compiled ) + r = VM_CallCompiled( vm, (int*)&callnum ); + else +#endif + r = VM_CallInterpreted( vm, (int*)&callnum ); +#else + struct { + int callnum; + int args[10]; + } a; + va_list ap; + + a.callnum = callnum; + va_start(ap, callnum); + for (i = 0; i < sizeof (a.args) / sizeof (a.args[0]); i++) { + a.args[i] = va_arg(ap, int); + } + va_end(ap); +#ifndef NO_VM_COMPILED + if ( vm->compiled ) + r = VM_CallCompiled( vm, &a.callnum ); + else +#endif + r = VM_CallInterpreted( vm, &a.callnum ); +#endif + } + + if ( oldVM != NULL ) // bk001220 - assert(currentVM!=NULL) for oldVM==NULL + currentVM = oldVM; + return r; +} + +//================================================================= + +static int QDECL VM_ProfileSort( const void *a, const void *b ) { + vmSymbol_t *sa, *sb; + + sa = *(vmSymbol_t **)a; + sb = *(vmSymbol_t **)b; + + if ( sa->profileCount < sb->profileCount ) { + return -1; + } + if ( sa->profileCount > sb->profileCount ) { + return 1; + } + return 0; +} + +/* +============== +VM_VmProfile_f + +============== +*/ +void VM_VmProfile_f( void ) { + vm_t *vm; + vmSymbol_t **sorted, *sym; + int i; + double total; + + if ( !lastVM ) { + return; + } + + vm = lastVM; + + if ( !vm->numSymbols ) { + return; + } + + sorted = Z_Malloc( vm->numSymbols * sizeof( *sorted ) ); + sorted[0] = vm->symbols; + total = sorted[0]->profileCount; + for ( i = 1 ; i < vm->numSymbols ; i++ ) { + sorted[i] = sorted[i-1]->next; + total += sorted[i]->profileCount; + } + + qsort( sorted, vm->numSymbols, sizeof( *sorted ), VM_ProfileSort ); + + for ( i = 0 ; i < vm->numSymbols ; i++ ) { + int perc; + + sym = sorted[i]; + + perc = 100 * (float) sym->profileCount / total; + Com_Printf( "%2i%% %9i %s\n", perc, sym->profileCount, sym->symName ); + sym->profileCount = 0; + } + + Com_Printf(" %9.0f total\n", total ); + + Z_Free( sorted ); +} + +/* +============== +VM_VmInfo_f + +============== +*/ +void VM_VmInfo_f( void ) { + vm_t *vm; + int i; + + Com_Printf( "Registered virtual machines:\n" ); + for ( i = 0 ; i < MAX_VM ; i++ ) { + vm = &vmTable[i]; + if ( !vm->name[0] ) { + break; + } + Com_Printf( "%s : ", vm->name ); + if ( vm->dllHandle ) { + Com_Printf( "native\n" ); + continue; + } + if ( vm->compiled ) { + Com_Printf( "compiled on load\n" ); + } else { + Com_Printf( "interpreted\n" ); + } + Com_Printf( " code length : %7i\n", vm->codeLength ); + Com_Printf( " table length: %7i\n", vm->instructionPointersLength ); + Com_Printf( " data length : %7i\n", vm->dataMask + 1 ); + } +} + +/* +=============== +VM_LogSyscalls + +Insert calls to this while debugging the vm compiler +=============== +*/ +void VM_LogSyscalls( int *args ) { + static int callnum; + static FILE *f; + + if ( !f ) { + f = fopen("syscalls.log", "w" ); + } + callnum++; + fprintf(f, "%i: %p (%i) = %i %i %i %i\n", callnum, (void*)(args - (int *)currentVM->dataBase), + args[0], args[1], args[2], args[3], args[4] ); +} |