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ioq3/code/qcommon/vm_interpreted.c

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/*
===========================================================================
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
===========================================================================
*/
#include "vm_local.h"
//#define DEBUG_VM
#ifdef DEBUG_VM
static char *opnames[256] = {
"OP_UNDEF",
"OP_IGNORE",
"OP_BREAK",
"OP_ENTER",
"OP_LEAVE",
"OP_CALL",
"OP_PUSH",
"OP_POP",
"OP_CONST",
"OP_LOCAL",
"OP_JUMP",
//-------------------
"OP_EQ",
"OP_NE",
"OP_LTI",
"OP_LEI",
"OP_GTI",
"OP_GEI",
"OP_LTU",
"OP_LEU",
"OP_GTU",
"OP_GEU",
"OP_EQF",
"OP_NEF",
"OP_LTF",
"OP_LEF",
"OP_GTF",
"OP_GEF",
//-------------------
"OP_LOAD1",
"OP_LOAD2",
"OP_LOAD4",
"OP_STORE1",
"OP_STORE2",
"OP_STORE4",
"OP_ARG",
"OP_BLOCK_COPY",
//-------------------
"OP_SEX8",
"OP_SEX16",
"OP_NEGI",
"OP_ADD",
"OP_SUB",
"OP_DIVI",
"OP_DIVU",
"OP_MODI",
"OP_MODU",
"OP_MULI",
"OP_MULU",
"OP_BAND",
"OP_BOR",
"OP_BXOR",
"OP_BCOM",
"OP_LSH",
"OP_RSHI",
"OP_RSHU",
"OP_NEGF",
"OP_ADDF",
"OP_SUBF",
"OP_DIVF",
"OP_MULF",
"OP_CVIF",
"OP_CVFI"
};
#endif
#if idppc
//FIXME: these, um... look the same to me
#if defined(__GNUC__)
static ID_INLINE unsigned int loadWord(void *addr) {
unsigned int word;
asm("lwbrx %0,0,%1" : "=r" (word) : "r" (addr));
return word;
}
#else
static ID_INLINE unsigned int __lwbrx(register void *addr,
register int offset) {
register unsigned int word;
asm("lwbrx %0,%2,%1" : "=r" (word) : "r" (addr), "b" (offset));
return word;
}
#define loadWord(addr) __lwbrx(addr,0)
#endif
#else
static ID_INLINE int loadWord(void *addr) {
int word;
memcpy(&word, addr, 4);
return LittleLong(word);
}
#endif
char *VM_Indent( vm_t *vm ) {
static char *string = " ";
if ( vm->callLevel > 20 ) {
return string;
}
return string + 2 * ( 20 - vm->callLevel );
}
void VM_StackTrace( vm_t *vm, int programCounter, int programStack ) {
int count;
count = 0;
do {
Com_Printf( "%s\n", VM_ValueToSymbol( vm, programCounter ) );
programStack = *(int *)&vm->dataBase[programStack+4];
programCounter = *(int *)&vm->dataBase[programStack];
} while ( programCounter != -1 && ++count < 32 );
}
/*
====================
VM_PrepareInterpreter
====================
*/
void VM_PrepareInterpreter( vm_t *vm, vmHeader_t *header ) {
int op;
int byte_pc;
int int_pc;
byte *code;
int instruction;
int *codeBase;
vm->codeBase = Hunk_Alloc( vm->codeLength*4, h_high ); // we're now int aligned
// memcpy( vm->codeBase, (byte *)header + header->codeOffset, vm->codeLength );
// we don't need to translate the instructions, but we still need
// to find each instructions starting point for jumps
int_pc = byte_pc = 0;
instruction = 0;
code = (byte *)header + header->codeOffset;
codeBase = (int *)vm->codeBase;
// Copy and expand instructions to words while building instruction table
while ( instruction < header->instructionCount ) {
vm->instructionPointers[ instruction ] = int_pc;
instruction++;
op = (int)code[ byte_pc ];
codeBase[int_pc] = op;
if(byte_pc > header->codeLength)
Com_Error(ERR_DROP, "VM_PrepareInterpreter: pc > header->codeLength");
byte_pc++;
int_pc++;
// these are the only opcodes that aren't a single byte
switch ( op ) {
case OP_ENTER:
case OP_CONST:
case OP_LOCAL:
case OP_LEAVE:
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:
case OP_EQF:
case OP_NEF:
case OP_LTF:
case OP_LEF:
case OP_GTF:
case OP_GEF:
case OP_BLOCK_COPY:
codeBase[int_pc] = loadWord(&code[byte_pc]);
byte_pc += 4;
int_pc++;
break;
case OP_ARG:
codeBase[int_pc] = (int)code[byte_pc];
byte_pc++;
int_pc++;
break;
default:
break;
}
}
int_pc = 0;
instruction = 0;
// Now that the code has been expanded to int-sized opcodes, we'll translate instruction index
//into an index into codeBase[], which contains opcodes and operands.
while ( instruction < header->instructionCount ) {
op = codeBase[ int_pc ];
instruction++;
int_pc++;
switch ( op ) {
// These ops need to translate addresses in jumps from instruction index to int index
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:
case OP_EQF:
case OP_NEF:
case OP_LTF:
case OP_LEF:
case OP_GTF:
case OP_GEF:
if(codeBase[int_pc] < 0 || codeBase[int_pc] > vm->instructionCount)
Com_Error(ERR_DROP, "VM_PrepareInterpreter: Jump to invalid instruction number");
// codeBase[pc] is the instruction index. Convert that into an offset into
//the int-aligned codeBase[] by the lookup table.
codeBase[int_pc] = vm->instructionPointers[codeBase[int_pc]];
int_pc++;
break;
// These opcodes have an operand that isn't an instruction index
case OP_ENTER:
case OP_CONST:
case OP_LOCAL:
case OP_LEAVE:
case OP_BLOCK_COPY:
case OP_ARG:
int_pc++;
break;
default:
break;
}
}
}
/*
==============
VM_Call
Upon a system call, the stack will look like:
sp+32 parm1
sp+28 parm0
sp+24 return stack
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 DEBUGSTR va("%s%i", VM_Indent(vm), opStackOfs)
int VM_CallInterpreted( vm_t *vm, int *args ) {
byte stack[OPSTACK_SIZE + 15];
register int *opStack;
register uint8_t opStackOfs;
int programCounter;
int programStack;
int stackOnEntry;
byte *image;
int *codeImage;
int v1;
int dataMask;
int arg;
#ifdef DEBUG_VM
vmSymbol_t *profileSymbol;
#endif
// interpret the code
vm->currentlyInterpreting = qtrue;
// we might be called recursively, so this might not be the very top
programStack = stackOnEntry = vm->programStack;
#ifdef DEBUG_VM
profileSymbol = VM_ValueToFunctionSymbol( vm, 0 );
// uncomment this for debugging breakpoints
vm->breakFunction = 0;
#endif
// set up the stack frame
image = vm->dataBase;
codeImage = (int *)vm->codeBase;
dataMask = vm->dataMask;
programCounter = 0;
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
VM_Debug(0);
// leave a free spot at start of stack so
// that as long as opStack is valid, opStack-1 will
// not corrupt anything
opStack = PADP(stack, 16);
*opStack = 0xDEADBEEF;
opStackOfs = 0;
// vm_debugLevel=2;
// main interpreter loop, will exit when a LEAVE instruction
// grabs the -1 program counter
#define r2 codeImage[programCounter]
while ( 1 ) {
int opcode, r0, r1;
// unsigned int r2;
nextInstruction:
r0 = opStack[opStackOfs];
r1 = opStack[(uint8_t) (opStackOfs - 1)];
nextInstruction2:
#ifdef DEBUG_VM
if ( (unsigned)programCounter >= vm->codeLength ) {
Com_Error( ERR_DROP, "VM pc out of range" );
return 0;
}
if ( programStack <= vm->stackBottom ) {
Com_Error( ERR_DROP, "VM stack overflow" );
return 0;
}
if ( programStack & 3 ) {
Com_Error( ERR_DROP, "VM program stack misaligned" );
return 0;
}
if ( vm_debugLevel > 1 ) {
Com_Printf( "%s %s\n", DEBUGSTR, opnames[opcode] );
}
profileSymbol->profileCount++;
#endif
opcode = codeImage[ programCounter++ ];
switch ( opcode ) {
#ifdef DEBUG_VM
default:
Com_Error( ERR_DROP, "Bad VM instruction" ); // this should be scanned on load!
return 0;
#endif
case OP_BREAK:
vm->breakCount++;
goto nextInstruction2;
case OP_CONST:
opStackOfs++;
r1 = r0;
r0 = opStack[opStackOfs] = r2;
programCounter += 1;
goto nextInstruction2;
case OP_LOCAL:
opStackOfs++;
r1 = r0;
r0 = opStack[opStackOfs] = r2+programStack;
programCounter += 1;
goto nextInstruction2;
case OP_LOAD4:
#ifdef DEBUG_VM
if(opStack[opStackOfs] & 3)
{
Com_Error( ERR_DROP, "OP_LOAD4 misaligned" );
return 0;
}
#endif
r0 = opStack[opStackOfs] = *(int *) &image[r0 & dataMask & ~3 ];
goto nextInstruction2;
case OP_LOAD2:
r0 = opStack[opStackOfs] = *(unsigned short *)&image[ r0&dataMask&~1 ];
goto nextInstruction2;
case OP_LOAD1:
r0 = opStack[opStackOfs] = image[ r0&dataMask ];
goto nextInstruction2;
case OP_STORE4:
*(int *)&image[ r1&(dataMask & ~3) ] = r0;
opStackOfs -= 2;
goto nextInstruction;
case OP_STORE2:
*(short *)&image[ r1&(dataMask & ~1) ] = r0;
opStackOfs -= 2;
goto nextInstruction;
case OP_STORE1:
image[ r1&dataMask ] = r0;
opStackOfs -= 2;
goto nextInstruction;
case OP_ARG:
// single byte offset from programStack
*(int *)&image[ (codeImage[programCounter] + programStack)&dataMask&~3 ] = r0;
opStackOfs--;
programCounter += 1;
goto nextInstruction;
case OP_BLOCK_COPY:
VM_BlockCopy(r1, r0, r2);
programCounter += 1;
opStackOfs -= 2;
goto nextInstruction;
case OP_CALL:
// save current program counter
*(int *)&image[ programStack ] = programCounter;
// jump to the location on the stack
programCounter = r0;
opStackOfs--;
if ( programCounter < 0 ) {
// system call
int r;
// int temp;
#ifdef DEBUG_VM
int stomped;
if ( vm_debugLevel ) {
Com_Printf( "%s---> systemcall(%i)\n", DEBUGSTR, -1 - programCounter );
}
#endif
// save the stack to allow recursive VM entry
// temp = vm->callLevel;
vm->programStack = programStack - 4;
#ifdef DEBUG_VM
stomped = *(int *)&image[ programStack + 4 ];
#endif
*(int *)&image[ programStack + 4 ] = -1 - programCounter;
//VM_LogSyscalls( (int *)&image[ programStack + 4 ] );
{
// the vm has ints on the stack, we expect
// pointers so we might have to convert it
if (sizeof(intptr_t) != sizeof(int)) {
intptr_t argarr[ MAX_VMSYSCALL_ARGS ];
int *imagePtr = (int *)&image[ programStack ];
int i;
for (i = 0; i < ARRAY_LEN(argarr); ++i) {
argarr[i] = *(++imagePtr);
}
r = vm->systemCall( argarr );
} else {
intptr_t* argptr = (intptr_t *)&image[ programStack + 4 ];
r = vm->systemCall( argptr );
}
}
#ifdef DEBUG_VM
// this is just our stack frame pointer, only needed
// for debugging
*(int *)&image[ programStack + 4 ] = stomped;
#endif
// save return value
opStackOfs++;
opStack[opStackOfs] = r;
programCounter = *(int *)&image[ programStack ];
// vm->callLevel = temp;
#ifdef DEBUG_VM
if ( vm_debugLevel ) {
Com_Printf( "%s<--- %s\n", DEBUGSTR, VM_ValueToSymbol( vm, programCounter ) );
}
#endif
} else if ( (unsigned)programCounter >= vm->instructionCount ) {
Com_Error( ERR_DROP, "VM program counter out of range in OP_CALL" );
return 0;
} else {
programCounter = vm->instructionPointers[ programCounter ];
}
goto nextInstruction;
// push and pop are only needed for discarded or bad function return values
case OP_PUSH:
opStackOfs++;
goto nextInstruction;
case OP_POP:
opStackOfs--;
goto nextInstruction;
case OP_ENTER:
#ifdef DEBUG_VM
profileSymbol = VM_ValueToFunctionSymbol( vm, programCounter );
#endif
// get size of stack frame
v1 = r2;
programCounter += 1;
programStack -= v1;
#ifdef DEBUG_VM
// save old stack frame for debugging traces
*(int *)&image[programStack+4] = programStack + v1;
if ( vm_debugLevel ) {
Com_Printf( "%s---> %s\n", DEBUGSTR, VM_ValueToSymbol( vm, programCounter - 5 ) );
if ( vm->breakFunction && programCounter - 5 == vm->breakFunction ) {
// this is to allow setting breakpoints here in the debugger
vm->breakCount++;
// vm_debugLevel = 2;
// VM_StackTrace( vm, programCounter, programStack );
}
// vm->callLevel++;
}
#endif
goto nextInstruction;
case OP_LEAVE:
// remove our stack frame
v1 = r2;
programStack += v1;
// grab the saved program counter
programCounter = *(int *)&image[ programStack ];
#ifdef DEBUG_VM
profileSymbol = VM_ValueToFunctionSymbol( vm, programCounter );
if ( vm_debugLevel ) {
// vm->callLevel--;
Com_Printf( "%s<--- %s\n", DEBUGSTR, VM_ValueToSymbol( vm, programCounter ) );
}
#endif
// check for leaving the VM
if ( programCounter == -1 ) {
goto done;
} else if ( (unsigned)programCounter >= vm->codeLength ) {
Com_Error( ERR_DROP, "VM program counter out of range in OP_LEAVE" );
return 0;
}
goto nextInstruction;
/*
===================================================================
BRANCHES
===================================================================
*/
case OP_JUMP:
if ( (unsigned)r0 >= vm->instructionCount )
{
Com_Error( ERR_DROP, "VM program counter out of range in OP_JUMP" );
return 0;
}
programCounter = vm->instructionPointers[ r0 ];
opStackOfs--;
goto nextInstruction;
case OP_EQ:
opStackOfs -= 2;
if ( r1 == r0 ) {
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_NE:
opStackOfs -= 2;
if ( r1 != r0 ) {
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_LTI:
opStackOfs -= 2;
if ( r1 < r0 ) {
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_LEI:
opStackOfs -= 2;
if ( r1 <= r0 ) {
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_GTI:
opStackOfs -= 2;
if ( r1 > r0 ) {
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_GEI:
opStackOfs -= 2;
if ( r1 >= r0 ) {
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_LTU:
opStackOfs -= 2;
if ( ((unsigned)r1) < ((unsigned)r0) ) {
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_LEU:
opStackOfs -= 2;
if ( ((unsigned)r1) <= ((unsigned)r0) ) {
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_GTU:
opStackOfs -= 2;
if ( ((unsigned)r1) > ((unsigned)r0) ) {
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_GEU:
opStackOfs -= 2;
if ( ((unsigned)r1) >= ((unsigned)r0) ) {
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_EQF:
opStackOfs -= 2;
if(((float *) opStack)[(uint8_t) (opStackOfs + 1)] == ((float *) opStack)[(uint8_t) (opStackOfs + 2)])
{
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_NEF:
opStackOfs -= 2;
if(((float *) opStack)[(uint8_t) (opStackOfs + 1)] != ((float *) opStack)[(uint8_t) (opStackOfs + 2)])
{
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_LTF:
opStackOfs -= 2;
if(((float *) opStack)[(uint8_t) (opStackOfs + 1)] < ((float *) opStack)[(uint8_t) (opStackOfs + 2)])
{
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_LEF:
opStackOfs -= 2;
if(((float *) opStack)[(uint8_t) ((uint8_t) (opStackOfs + 1))] <= ((float *) opStack)[(uint8_t) ((uint8_t) (opStackOfs + 2))])
{
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_GTF:
opStackOfs -= 2;
if(((float *) opStack)[(uint8_t) (opStackOfs + 1)] > ((float *) opStack)[(uint8_t) (opStackOfs + 2)])
{
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
case OP_GEF:
opStackOfs -= 2;
if(((float *) opStack)[(uint8_t) (opStackOfs + 1)] >= ((float *) opStack)[(uint8_t) (opStackOfs + 2)])
{
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
programCounter += 1;
goto nextInstruction;
}
//===================================================================
case OP_NEGI:
opStack[opStackOfs] = -r0;
goto nextInstruction;
case OP_ADD:
opStackOfs--;
opStack[opStackOfs] = r1 + r0;
goto nextInstruction;
case OP_SUB:
opStackOfs--;
opStack[opStackOfs] = r1 - r0;
goto nextInstruction;
case OP_DIVI:
opStackOfs--;
opStack[opStackOfs] = r1 / r0;
goto nextInstruction;
case OP_DIVU:
opStackOfs--;
opStack[opStackOfs] = ((unsigned) r1) / ((unsigned) r0);
goto nextInstruction;
case OP_MODI:
opStackOfs--;
opStack[opStackOfs] = r1 % r0;
goto nextInstruction;
case OP_MODU:
opStackOfs--;
opStack[opStackOfs] = ((unsigned) r1) % ((unsigned) r0);
goto nextInstruction;
case OP_MULI:
opStackOfs--;
opStack[opStackOfs] = r1 * r0;
goto nextInstruction;
case OP_MULU:
opStackOfs--;
opStack[opStackOfs] = ((unsigned) r1) * ((unsigned) r0);
goto nextInstruction;
case OP_BAND:
opStackOfs--;
opStack[opStackOfs] = ((unsigned) r1) & ((unsigned) r0);
goto nextInstruction;
case OP_BOR:
opStackOfs--;
opStack[opStackOfs] = ((unsigned) r1) | ((unsigned) r0);
goto nextInstruction;
case OP_BXOR:
opStackOfs--;
opStack[opStackOfs] = ((unsigned) r1) ^ ((unsigned) r0);
goto nextInstruction;
case OP_BCOM:
opStack[opStackOfs] = ~((unsigned) r0);
goto nextInstruction;
case OP_LSH:
opStackOfs--;
opStack[opStackOfs] = r1 << r0;
goto nextInstruction;
case OP_RSHI:
opStackOfs--;
opStack[opStackOfs] = r1 >> r0;
goto nextInstruction;
case OP_RSHU:
opStackOfs--;
opStack[opStackOfs] = ((unsigned) r1) >> r0;
goto nextInstruction;
case OP_NEGF:
((float *) opStack)[opStackOfs] = -((float *) opStack)[opStackOfs];
goto nextInstruction;
case OP_ADDF:
opStackOfs--;
((float *) opStack)[opStackOfs] = ((float *) opStack)[opStackOfs] + ((float *) opStack)[(uint8_t) (opStackOfs + 1)];
goto nextInstruction;
case OP_SUBF:
opStackOfs--;
((float *) opStack)[opStackOfs] = ((float *) opStack)[opStackOfs] - ((float *) opStack)[(uint8_t) (opStackOfs + 1)];
goto nextInstruction;
case OP_DIVF:
opStackOfs--;
((float *) opStack)[opStackOfs] = ((float *) opStack)[opStackOfs] / ((float *) opStack)[(uint8_t) (opStackOfs + 1)];
goto nextInstruction;
case OP_MULF:
opStackOfs--;
((float *) opStack)[opStackOfs] = ((float *) opStack)[opStackOfs] * ((float *) opStack)[(uint8_t) (opStackOfs + 1)];
goto nextInstruction;
case OP_CVIF:
((float *) opStack)[opStackOfs] = (float) opStack[opStackOfs];
goto nextInstruction;
case OP_CVFI:
opStack[opStackOfs] = Q_ftol(((float *) opStack)[opStackOfs]);
goto nextInstruction;
case OP_SEX8:
opStack[opStackOfs] = (signed char) opStack[opStackOfs];
goto nextInstruction;
case OP_SEX16:
opStack[opStackOfs] = (short) opStack[opStackOfs];
goto nextInstruction;
}
}
done:
vm->currentlyInterpreting = qfalse;
if (opStackOfs != 1 || *opStack != 0xDEADBEEF)
Com_Error(ERR_DROP, "Interpreter error: opStack[0] = %X, opStackOfs = %d", opStack[0], opStackOfs);
vm->programStack = stackOnEntry;
// return the result
return opStack[opStackOfs];
}
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