jediacademy/codemp/qcommon/vm_ppc.cpp
2013-04-04 17:35:38 -05:00

1274 lines
44 KiB
C++

// vm_ppc.c
// ppc dynamic compiler
#include "vm_local.h"
#pragma opt_pointer_analysis off
typedef enum {
R_REAL_STACK = 1,
// registers 3-11 are the parameter passing registers
// state
R_STACK = 3, // local
R_OPSTACK, // global
// constants
R_MEMBASE, // global
R_MEMMASK,
R_ASMCALL, // global
R_INSTRUCTIONS, // global
R_NUM_INSTRUCTIONS, // global
R_CVM, // currentVM
// temps
R_TOP = 12,
R_SECOND = 13,
R_EA = 14 // effective address calculation
} regNums_t;
#define RG_REAL_STACK r1
#define RG_STACK r3
#define RG_OPSTACK r4
#define RG_MEMBASE r5
#define RG_MEMMASK r6
#define RG_ASMCALL r7
#define RG_INSTRUCTIONS r8
#define RG_NUM_INSTRUCTIONS r9
#define RG_CVM r10
#define RG_TOP r12
#define RG_SECOND r13
#define RG_EA r14
// this doesn't have the low order bits set for instructions i'm not using...
typedef enum {
PPC_TDI = 0x08000000,
PPC_TWI = 0x0c000000,
PPC_MULLI = 0x1c000000,
PPC_SUBFIC = 0x20000000,
PPC_CMPI = 0x28000000,
PPC_CMPLI = 0x2c000000,
PPC_ADDIC = 0x30000000,
PPC_ADDIC_ = 0x34000000,
PPC_ADDI = 0x38000000,
PPC_ADDIS = 0x3c000000,
PPC_BC = 0x40000000,
PPC_SC = 0x44000000,
PPC_B = 0x48000000,
PPC_MCRF = 0x4c000000,
PPC_BCLR = 0x4c000020,
PPC_RFID = 0x4c000000,
PPC_CRNOR = 0x4c000000,
PPC_RFI = 0x4c000000,
PPC_CRANDC = 0x4c000000,
PPC_ISYNC = 0x4c000000,
PPC_CRXOR = 0x4c000000,
PPC_CRNAND = 0x4c000000,
PPC_CREQV = 0x4c000000,
PPC_CRORC = 0x4c000000,
PPC_CROR = 0x4c000000,
//------------
PPC_BCCTR = 0x4c000420,
PPC_RLWIMI = 0x50000000,
PPC_RLWINM = 0x54000000,
PPC_RLWNM = 0x5c000000,
PPC_ORI = 0x60000000,
PPC_ORIS = 0x64000000,
PPC_XORI = 0x68000000,
PPC_XORIS = 0x6c000000,
PPC_ANDI_ = 0x70000000,
PPC_ANDIS_ = 0x74000000,
PPC_RLDICL = 0x78000000,
PPC_RLDICR = 0x78000000,
PPC_RLDIC = 0x78000000,
PPC_RLDIMI = 0x78000000,
PPC_RLDCL = 0x78000000,
PPC_RLDCR = 0x78000000,
PPC_CMP = 0x7c000000,
PPC_TW = 0x7c000000,
PPC_SUBFC = 0x7c000010,
PPC_MULHDU = 0x7c000000,
PPC_ADDC = 0x7c000014,
PPC_MULHWU = 0x7c000000,
PPC_MFCR = 0x7c000000,
PPC_LWAR = 0x7c000000,
PPC_LDX = 0x7c000000,
PPC_LWZX = 0x7c00002e,
PPC_SLW = 0x7c000030,
PPC_CNTLZW = 0x7c000000,
PPC_SLD = 0x7c000000,
PPC_AND = 0x7c000038,
PPC_CMPL = 0x7c000040,
PPC_SUBF = 0x7c000050,
PPC_LDUX = 0x7c000000,
//------------
PPC_DCBST = 0x7c000000,
PPC_LWZUX = 0x7c00006c,
PPC_CNTLZD = 0x7c000000,
PPC_ANDC = 0x7c000000,
PPC_TD = 0x7c000000,
PPC_MULHD = 0x7c000000,
PPC_MULHW = 0x7c000000,
PPC_MTSRD = 0x7c000000,
PPC_MFMSR = 0x7c000000,
PPC_LDARX = 0x7c000000,
PPC_DCBF = 0x7c000000,
PPC_LBZX = 0x7c0000ae,
PPC_NEG = 0x7c000000,
PPC_MTSRDIN = 0x7c000000,
PPC_LBZUX = 0x7c000000,
PPC_NOR = 0x7c0000f8,
PPC_SUBFE = 0x7c000000,
PPC_ADDE = 0x7c000000,
PPC_MTCRF = 0x7c000000,
PPC_MTMSR = 0x7c000000,
PPC_STDX = 0x7c000000,
PPC_STWCX_ = 0x7c000000,
PPC_STWX = 0x7c00012e,
PPC_MTMSRD = 0x7c000000,
PPC_STDUX = 0x7c000000,
PPC_STWUX = 0x7c00016e,
PPC_SUBFZE = 0x7c000000,
PPC_ADDZE = 0x7c000000,
PPC_MTSR = 0x7c000000,
PPC_STDCX_ = 0x7c000000,
PPC_STBX = 0x7c0001ae,
PPC_SUBFME = 0x7c000000,
PPC_MULLD = 0x7c000000,
//------------
PPC_ADDME = 0x7c000000,
PPC_MULLW = 0x7c0001d6,
PPC_MTSRIN = 0x7c000000,
PPC_DCBTST = 0x7c000000,
PPC_STBUX = 0x7c000000,
PPC_ADD = 0x7c000214,
PPC_DCBT = 0x7c000000,
PPC_LHZX = 0x7c00022e,
PPC_EQV = 0x7c000000,
PPC_TLBIE = 0x7c000000,
PPC_ECIWX = 0x7c000000,
PPC_LHZUX = 0x7c000000,
PPC_XOR = 0x7c000278,
PPC_MFSPR = 0x7c0002a6,
PPC_LWAX = 0x7c000000,
PPC_LHAX = 0x7c000000,
PPC_TLBIA = 0x7c000000,
PPC_MFTB = 0x7c000000,
PPC_LWAUX = 0x7c000000,
PPC_LHAUX = 0x7c000000,
PPC_STHX = 0x7c00032e,
PPC_ORC = 0x7c000338,
PPC_SRADI = 0x7c000000,
PPC_SLBIE = 0x7c000000,
PPC_ECOWX = 0x7c000000,
PPC_STHUX = 0x7c000000,
PPC_OR = 0x7c000378,
PPC_DIVDU = 0x7c000000,
PPC_DIVWU = 0x7c000396,
PPC_MTSPR = 0x7c0003a6,
PPC_DCBI = 0x7c000000,
PPC_NAND = 0x7c000000,
PPC_DIVD = 0x7c000000,
//------------
PPC_DIVW = 0x7c0003d6,
PPC_SLBIA = 0x7c000000,
PPC_MCRXR = 0x7c000000,
PPC_LSWX = 0x7c000000,
PPC_LWBRX = 0x7c000000,
PPC_LFSX = 0x7c000000,
PPC_SRW = 0x7c000430,
PPC_SRD = 0x7c000000,
PPC_TLBSYNC = 0x7c000000,
PPC_LFSUX = 0x7c000000,
PPC_MFSR = 0x7c000000,
PPC_LSWI = 0x7c000000,
PPC_SYNC = 0x7c000000,
PPC_LFDX = 0x7c000000,
PPC_LFDUX = 0x7c000000,
PPC_MFSRIN = 0x7c000000,
PPC_STSWX = 0x7c000000,
PPC_STWBRX = 0x7c000000,
PPC_STFSX = 0x7c000000,
PPC_STFSUX = 0x7c000000,
PPC_STSWI = 0x7c000000,
PPC_STFDX = 0x7c000000,
PPC_DCBA = 0x7c000000,
PPC_STFDUX = 0x7c000000,
PPC_LHBRX = 0x7c000000,
PPC_SRAW = 0x7c000630,
PPC_SRAD = 0x7c000000,
PPC_SRAWI = 0x7c000000,
PPC_EIEIO = 0x7c000000,
PPC_STHBRX = 0x7c000000,
PPC_EXTSH = 0x7c000734,
PPC_EXTSB = 0x7c000774,
PPC_ICBI = 0x7c000000,
//------------
PPC_STFIWX = 0x7c0007ae,
PPC_EXTSW = 0x7c000000,
PPC_DCBZ = 0x7c000000,
PPC_LWZ = 0x80000000,
PPC_LWZU = 0x84000000,
PPC_LBZ = 0x88000000,
PPC_LBZU = 0x8c000000,
PPC_STW = 0x90000000,
PPC_STWU = 0x94000000,
PPC_STB = 0x98000000,
PPC_STBU = 0x9c000000,
PPC_LHZ = 0xa0000000,
PPC_LHZU = 0xa4000000,
PPC_LHA = 0xa8000000,
PPC_LHAU = 0xac000000,
PPC_STH = 0xb0000000,
PPC_STHU = 0xb4000000,
PPC_LMW = 0xb8000000,
PPC_STMW = 0xbc000000,
PPC_LFS = 0xc0000000,
PPC_LFSU = 0xc4000000,
PPC_LFD = 0xc8000000,
PPC_LFDU = 0xcc000000,
PPC_STFS = 0xd0000000,
PPC_STFSU = 0xd4000000,
PPC_STFD = 0xd8000000,
PPC_STFDU = 0xdc000000,
PPC_LD = 0xe8000000,
PPC_LDU = 0xe8000001,
PPC_LWA = 0xe8000002,
PPC_FDIVS = 0xec000024,
PPC_FSUBS = 0xec000028,
PPC_FADDS = 0xec00002a,
//------------
PPC_FSQRTS = 0xec000000,
PPC_FRES = 0xec000000,
PPC_FMULS = 0xec000032,
PPC_FMSUBS = 0xec000000,
PPC_FMADDS = 0xec000000,
PPC_FNMSUBS = 0xec000000,
PPC_FNMADDS = 0xec000000,
PPC_STD = 0xf8000000,
PPC_STDU = 0xf8000001,
PPC_FCMPU = 0xfc000000,
PPC_FRSP = 0xfc000018,
PPC_FCTIW = 0xfc000000,
PPC_FCTIWZ = 0xfc00001e,
PPC_FDIV = 0xfc000000,
PPC_FSUB = 0xfc000028,
PPC_FADD = 0xfc000000,
PPC_FSQRT = 0xfc000000,
PPC_FSEL = 0xfc000000,
PPC_FMUL = 0xfc000000,
PPC_FRSQRTE = 0xfc000000,
PPC_FMSUB = 0xfc000000,
PPC_FMADD = 0xfc000000,
PPC_FNMSUB = 0xfc000000,
PPC_FNMADD = 0xfc000000,
PPC_FCMPO = 0xfc000000,
PPC_MTFSB1 = 0xfc000000,
PPC_FNEG = 0xfc000050,
PPC_MCRFS = 0xfc000000,
PPC_MTFSB0 = 0xfc000000,
PPC_FMR = 0xfc000000,
PPC_MTFSFI = 0xfc000000,
PPC_FNABS = 0xfc000000,
PPC_FABS = 0xfc000000,
//------------
PPC_MFFS = 0xfc000000,
PPC_MTFSF = 0xfc000000,
PPC_FCTID = 0xfc000000,
PPC_FCTIDZ = 0xfc000000,
PPC_FCFID = 0xfc000000
} ppcOpcodes_t;
// the newly generated code
static unsigned *buf;
static int compiledOfs; // in dwords
// fromt the original bytecode
static byte *code;
static int pc;
void AsmCall( void );
double itofConvert[2];
static int Constant4( void ) {
int v;
v = code[pc] | (code[pc+1]<<8) | (code[pc+2]<<16) | (code[pc+3]<<24);
pc += 4;
return v;
}
static int Constant1( void ) {
int v;
v = code[pc];
pc += 1;
return v;
}
static void Emit4( int i ) {
buf[ compiledOfs ] = i;
compiledOfs++;
}
static void Inst( int opcode, int destReg, int aReg, int bReg ) {
unsigned r;
r = opcode | ( destReg << 21 ) | ( aReg << 16 ) | ( bReg << 11 ) ;
buf[ compiledOfs ] = r;
compiledOfs++;
}
static void Inst4( int opcode, int destReg, int aReg, int bReg, int cReg ) {
unsigned r;
r = opcode | ( destReg << 21 ) | ( aReg << 16 ) | ( bReg << 11 ) | ( cReg << 6 );
buf[ compiledOfs ] = r;
compiledOfs++;
}
static void InstImm( int opcode, int destReg, int aReg, int immediate ) {
unsigned r;
if ( immediate > 32767 || immediate < -32768 ) {
Com_Error( ERR_FATAL, "VM_Compile: immediate value %i out of range, opcode %x,%d,%d", immediate, opcode, destReg, aReg );
}
r = opcode | ( destReg << 21 ) | ( aReg << 16 ) | ( immediate & 0xffff );
buf[ compiledOfs ] = r;
compiledOfs++;
}
static void InstImmU( int opcode, int destReg, int aReg, int immediate ) {
unsigned r;
if ( immediate > 0xffff || immediate < 0 ) {
Com_Error( ERR_FATAL, "VM_Compile: immediate value %i out of range", immediate );
}
r = opcode | ( destReg << 21 ) | ( aReg << 16 ) | ( immediate & 0xffff );
buf[ compiledOfs ] = r;
compiledOfs++;
}
static qboolean rtopped;
static int pop0, pop1, oc0, oc1;
static vm_t *tvm;
static int instruction;
static byte *jused;
static int pass;
static void ltop() {
if (rtopped == qfalse) {
InstImm( PPC_LWZ, R_TOP, R_OPSTACK, 0 ); // get value from opstack
}
}
static void ltopandsecond() {
if (pass>=0 && buf[compiledOfs-1] == (PPC_STWU | R_TOP<<21 | R_OPSTACK<<16 | 4 ) && jused[instruction]==0 ) {
compiledOfs--;
if (!pass) {
tvm->instructionPointers[instruction] = compiledOfs * 4;
}
InstImm( PPC_LWZ, R_SECOND, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -4 );
} else if (pass>=0 && buf[compiledOfs-1] == (PPC_STW | R_TOP<<21 | R_OPSTACK<<16 | 0 ) && jused[instruction]==0 ) {
compiledOfs--;
if (!pass) {
tvm->instructionPointers[instruction] = compiledOfs * 4;
}
InstImm( PPC_LWZ, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -8 );
} else {
ltop(); // get value from opstack
InstImm( PPC_LWZ, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -8 );
}
rtopped = qfalse;
}
// TJW: Unused
#if 0
static void fltop() {
if (rtopped == qfalse) {
InstImm( PPC_LFS, R_TOP, R_OPSTACK, 0 ); // get value from opstack
}
}
#endif
static void fltopandsecond() {
InstImm( PPC_LFS, R_TOP, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_LFS, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -8 );
rtopped = qfalse;
return;
}
/*
=================
VM_Compile
=================
*/
void VM_Compile( vm_t *vm, vmHeader_t *header ) {
int op;
int maxLength;
int v;
int i;
// set up the into-to-float variables
((int *)itofConvert)[0] = 0x43300000;
((int *)itofConvert)[1] = 0x80000000;
((int *)itofConvert)[2] = 0x43300000;
// allocate a very large temp buffer, we will shrink it later
maxLength = header->codeLength * 8;
buf = Z_Malloc( maxLength,qfalse );
jused = Z_Malloc(header->instructionCount + 2,qfalse);
Com_Memset(jused, 0, header->instructionCount+2);
// compile everything twice, so the second pass will have valid instruction
// pointers for branches
for ( pass = -1 ; pass < 2 ; pass++ ) {
rtopped = qfalse;
// translate all instructions
pc = 0;
pop0 = 343545;
pop1 = 2443545;
oc0 = -2343535;
oc1 = 24353454;
tvm = vm;
code = (byte *)header + header->codeOffset;
compiledOfs = 0;
#ifndef __GNUC__
// metrowerks seems to require this header in front of functions
Emit4( (int)(buf+2) );
Emit4( 0 );
#endif
for ( instruction = 0 ; instruction < header->instructionCount ; instruction++ ) {
if ( compiledOfs*4 > maxLength - 16 ) {
Com_Error( ERR_DROP, "VM_Compile: maxLength exceeded" );
}
op = code[ pc ];
if ( !pass ) {
vm->instructionPointers[ instruction ] = compiledOfs * 4;
}
pc++;
switch ( op ) {
case 0:
break;
case OP_BREAK:
InstImmU( PPC_ADDI, R_TOP, 0, 0 );
InstImm( PPC_LWZ, R_TOP, R_TOP, 0 ); // *(int *)0 to crash to debugger
rtopped = qfalse;
break;
case OP_ENTER:
InstImm( PPC_ADDI, R_STACK, R_STACK, -Constant4() ); // sub R_STACK, R_STACK, imm
rtopped = qfalse;
break;
case OP_CONST:
v = Constant4();
if (code[pc] == OP_LOAD4 || code[pc] == OP_LOAD2 || code[pc] == OP_LOAD1) {
v &= vm->dataMask;
}
if ( v < 32768 && v >= -32768 ) {
InstImmU( PPC_ADDI, R_TOP, 0, v & 0xffff );
} else {
InstImmU( PPC_ADDIS, R_TOP, 0, (v >> 16)&0xffff );
if ( v & 0xffff ) {
InstImmU( PPC_ORI, R_TOP, R_TOP, v & 0xffff );
}
}
if (code[pc] == OP_LOAD4) {
Inst( PPC_LWZX, R_TOP, R_TOP, R_MEMBASE ); // load from memory base
pc++;
instruction++;
} else if (code[pc] == OP_LOAD2) {
Inst( PPC_LHZX, R_TOP, R_TOP, R_MEMBASE ); // load from memory base
pc++;
instruction++;
} else if (code[pc] == OP_LOAD1) {
Inst( PPC_LBZX, R_TOP, R_TOP, R_MEMBASE ); // load from memory base
pc++;
instruction++;
}
if (code[pc] == OP_STORE4) {
InstImm( PPC_LWZ, R_SECOND, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -4 );
//Inst( PPC_AND, R_MEMMASK, R_SECOND, R_SECOND ); // mask it
Inst( PPC_STWX, R_TOP, R_SECOND, R_MEMBASE ); // store from memory base
pc++;
instruction++;
rtopped = qfalse;
break;
} else if (code[pc] == OP_STORE2) {
InstImm( PPC_LWZ, R_SECOND, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -4 );
//Inst( PPC_AND, R_MEMMASK, R_SECOND, R_SECOND ); // mask it
Inst( PPC_STHX, R_TOP, R_SECOND, R_MEMBASE ); // store from memory base
pc++;
instruction++;
rtopped = qfalse;
break;
} else if (code[pc] == OP_STORE1) {
InstImm( PPC_LWZ, R_SECOND, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -4 );
//Inst( PPC_AND, R_MEMMASK, R_SECOND, R_SECOND ); // mask it
Inst( PPC_STBX, R_TOP, R_SECOND, R_MEMBASE ); // store from memory base
pc++;
instruction++;
rtopped = qfalse;
break;
}
if (code[pc] == OP_JUMP) {
jused[v] = 1;
}
InstImm( PPC_STWU, R_TOP, R_OPSTACK, 4 );
rtopped = qtrue;
break;
case OP_LOCAL:
oc0 = oc1;
oc1 = Constant4();
if (code[pc] == OP_LOAD4 || code[pc] == OP_LOAD2 || code[pc] == OP_LOAD1) {
oc1 &= vm->dataMask;
}
InstImm( PPC_ADDI, R_TOP, R_STACK, oc1 );
if (code[pc] == OP_LOAD4) {
Inst( PPC_LWZX, R_TOP, R_TOP, R_MEMBASE ); // load from memory base
pc++;
instruction++;
} else if (code[pc] == OP_LOAD2) {
Inst( PPC_LHZX, R_TOP, R_TOP, R_MEMBASE ); // load from memory base
pc++;
instruction++;
} else if (code[pc] == OP_LOAD1) {
Inst( PPC_LBZX, R_TOP, R_TOP, R_MEMBASE ); // load from memory base
pc++;
instruction++;
}
if (code[pc] == OP_STORE4) {
InstImm( PPC_LWZ, R_SECOND, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -4 );
//Inst( PPC_AND, R_MEMMASK, R_SECOND, R_SECOND ); // mask it
Inst( PPC_STWX, R_TOP, R_SECOND, R_MEMBASE ); // store from memory base
pc++;
instruction++;
rtopped = qfalse;
break;
} else if (code[pc] == OP_STORE2) {
InstImm( PPC_LWZ, R_SECOND, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -4 );
//Inst( PPC_AND, R_MEMMASK, R_SECOND, R_SECOND ); // mask it
Inst( PPC_STHX, R_TOP, R_SECOND, R_MEMBASE ); // store from memory base
pc++;
instruction++;
rtopped = qfalse;
break;
} else if (code[pc] == OP_STORE1) {
InstImm( PPC_LWZ, R_SECOND, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -4 );
//Inst( PPC_AND, R_MEMMASK, R_SECOND, R_SECOND ); // mask it
Inst( PPC_STBX, R_TOP, R_SECOND, R_MEMBASE ); // store from memory base
pc++;
instruction++;
rtopped = qfalse;
break;
}
InstImm( PPC_STWU, R_TOP, R_OPSTACK, 4 );
rtopped = qtrue;
break;
case OP_ARG:
ltop(); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -4 );
InstImm( PPC_ADDI, R_EA, R_STACK, Constant1() ); // location to put it
Inst( PPC_STWX, R_TOP, R_EA, R_MEMBASE );
rtopped = qfalse;
break;
case OP_CALL:
Inst( PPC_MFSPR, R_SECOND, 8, 0 ); // move from link register
InstImm( PPC_STWU, R_SECOND, R_REAL_STACK, -16 ); // save off the old return address
Inst( PPC_MTSPR, R_ASMCALL, 9, 0 ); // move to count register
Inst( PPC_BCCTR | 1, 20, 0, 0 ); // jump and link to the count register
InstImm( PPC_LWZ, R_SECOND, R_REAL_STACK, 0 ); // fetch the old return address
InstImm( PPC_ADDI, R_REAL_STACK, R_REAL_STACK, 16 );
Inst( PPC_MTSPR, R_SECOND, 8, 0 ); // move to link register
rtopped = qfalse;
break;
case OP_PUSH:
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, 4 );
rtopped = qfalse;
break;
case OP_POP:
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -4 );
rtopped = qfalse;
break;
case OP_LEAVE:
InstImm( PPC_ADDI, R_STACK, R_STACK, Constant4() ); // add R_STACK, R_STACK, imm
Inst( PPC_BCLR, 20, 0, 0 ); // branch unconditionally to link register
rtopped = qfalse;
break;
case OP_LOAD4:
ltop(); // get value from opstack
//Inst( PPC_AND, R_MEMMASK, R_TOP, R_TOP ); // mask it
Inst( PPC_LWZX, R_TOP, R_TOP, R_MEMBASE ); // load from memory base
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 );
rtopped = qtrue;
break;
case OP_LOAD2:
ltop(); // get value from opstack
//Inst( PPC_AND, R_MEMMASK, R_TOP, R_TOP ); // mask it
Inst( PPC_LHZX, R_TOP, R_TOP, R_MEMBASE ); // load from memory base
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 );
rtopped = qtrue;
break;
case OP_LOAD1:
ltop(); // get value from opstack
//Inst( PPC_AND, R_MEMMASK, R_TOP, R_TOP ); // mask it
Inst( PPC_LBZX, R_TOP, R_TOP, R_MEMBASE ); // load from memory base
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 );
rtopped = qtrue;
break;
case OP_STORE4:
ltopandsecond(); // get value from opstack
//Inst( PPC_AND, R_MEMMASK, R_SECOND, R_SECOND ); // mask it
Inst( PPC_STWX, R_TOP, R_SECOND, R_MEMBASE ); // store from memory base
rtopped = qfalse;
break;
case OP_STORE2:
ltopandsecond(); // get value from opstack
//Inst( PPC_AND, R_MEMMASK, R_SECOND, R_SECOND ); // mask it
Inst( PPC_STHX, R_TOP, R_SECOND, R_MEMBASE ); // store from memory base
rtopped = qfalse;
break;
case OP_STORE1:
ltopandsecond(); // get value from opstack
//Inst( PPC_AND, R_MEMMASK, R_SECOND, R_SECOND ); // mask it
Inst( PPC_STBX, R_TOP, R_SECOND, R_MEMBASE ); // store from memory base
rtopped = qfalse;
break;
case OP_EQ:
ltopandsecond(); // get value from opstack
Inst( PPC_CMP, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
InstImm( PPC_BC, 4, 2, 8 );
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
Emit4(PPC_B | (v&0x3ffffff) );
rtopped = qfalse;
break;
case OP_NE:
ltopandsecond(); // get value from opstack
Inst( PPC_CMP, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
InstImm( PPC_BC, 12, 2, 8 );
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
Emit4(PPC_B | (unsigned int)(v&0x3ffffff) );
// InstImm( PPC_BC, 4, 2, v );
rtopped = qfalse;
break;
case OP_LTI:
ltopandsecond(); // get value from opstack
Inst( PPC_CMP, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
InstImm( PPC_BC, 4, 0, 8 );
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
Emit4(PPC_B | (unsigned int)(v&0x3ffffff) );
// InstImm( PPC_BC, 12, 0, v );
rtopped = qfalse;
break;
case OP_LEI:
ltopandsecond(); // get value from opstack
Inst( PPC_CMP, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
InstImm( PPC_BC, 12, 1, 8 );
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
Emit4(PPC_B | (unsigned int)(v&0x3ffffff) );
// InstImm( PPC_BC, 4, 1, v );
rtopped = qfalse;
break;
case OP_GTI:
ltopandsecond(); // get value from opstack
Inst( PPC_CMP, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
InstImm( PPC_BC, 4, 1, 8 );
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
Emit4(PPC_B | (unsigned int)(v&0x3ffffff) );
// InstImm( PPC_BC, 12, 1, v );
rtopped = qfalse;
break;
case OP_GEI:
ltopandsecond(); // get value from opstack
Inst( PPC_CMP, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 4, 0, v );
rtopped = qfalse;
break;
case OP_LTU:
ltopandsecond(); // get value from opstack
Inst( PPC_CMPL, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 12, 0, v );
rtopped = qfalse;
break;
case OP_LEU:
ltopandsecond(); // get value from opstack
Inst( PPC_CMPL, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 4, 1, v );
rtopped = qfalse;
break;
case OP_GTU:
ltopandsecond(); // get value from opstack
Inst( PPC_CMPL, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 12, 1, v );
rtopped = qfalse;
break;
case OP_GEU:
ltopandsecond(); // get value from opstack
Inst( PPC_CMPL, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 4, 0, v );
rtopped = qfalse;
break;
case OP_EQF:
fltopandsecond(); // get value from opstack
Inst( PPC_FCMPU, 0, R_TOP, R_SECOND );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 12, 2, v );
rtopped = qfalse;
break;
case OP_NEF:
fltopandsecond(); // get value from opstack
Inst( PPC_FCMPU, 0, R_TOP, R_SECOND );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 4, 2, v );
rtopped = qfalse;
break;
case OP_LTF:
fltopandsecond(); // get value from opstack
Inst( PPC_FCMPU, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 12, 0, v );
rtopped = qfalse;
break;
case OP_LEF:
fltopandsecond(); // get value from opstack
Inst( PPC_FCMPU, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 4, 1, v );
rtopped = qfalse;
break;
case OP_GTF:
fltopandsecond(); // get value from opstack
Inst( PPC_FCMPU, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 12, 1, v );
rtopped = qfalse;
break;
case OP_GEF:
fltopandsecond(); // get value from opstack
Inst( PPC_FCMPU, 0, R_SECOND, R_TOP );
i = Constant4();
jused[i] = 1;
if ( pass==1 ) {
v = vm->instructionPointers[ i ] - (int)&buf[compiledOfs];
} else {
v = 0;
}
InstImm( PPC_BC, 4, 0, v );
rtopped = qfalse;
break;
case OP_NEGI:
ltop(); // get value from opstack
InstImm( PPC_SUBFIC, R_TOP, R_TOP, 0 );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_ADD:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_ADD, R_TOP, R_TOP, R_SECOND );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_SUB:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_SUBF, R_TOP, R_TOP, R_SECOND );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_DIVI:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_DIVW, R_TOP, R_SECOND, R_TOP );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_DIVU:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_DIVWU, R_TOP, R_SECOND, R_TOP );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_MODI:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_DIVW, R_EA, R_SECOND, R_TOP );
Inst( PPC_MULLW, R_EA, R_TOP, R_EA );
Inst( PPC_SUBF, R_TOP, R_EA, R_SECOND );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_MODU:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_DIVWU, R_EA, R_SECOND, R_TOP );
Inst( PPC_MULLW, R_EA, R_TOP, R_EA );
Inst( PPC_SUBF, R_TOP, R_EA, R_SECOND );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_MULI:
case OP_MULU:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_MULLW, R_TOP, R_SECOND, R_TOP );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_BAND:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_AND, R_SECOND, R_TOP, R_TOP );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_BOR:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_OR, R_SECOND, R_TOP, R_TOP );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_BXOR:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_XOR, R_SECOND, R_TOP, R_TOP );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_BCOM:
ltop(); // get value from opstack
Inst( PPC_NOR, R_TOP, R_TOP, R_TOP );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_LSH:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_SLW, R_SECOND, R_TOP, R_TOP );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_RSHI:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_SRAW, R_SECOND, R_TOP, R_TOP );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_RSHU:
ltop(); // get value from opstack
InstImm( PPC_LWZU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_SRW, R_SECOND, R_TOP, R_TOP );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qtrue;
break;
case OP_NEGF:
InstImm( PPC_LFS, R_TOP, R_OPSTACK, 0 ); // get value from opstack
Inst( PPC_FNEG, R_TOP, 0, R_TOP );
InstImm( PPC_STFS, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qfalse;
break;
case OP_ADDF:
InstImm( PPC_LFS, R_TOP, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_LFSU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_FADDS, R_TOP, R_SECOND, R_TOP );
InstImm( PPC_STFS, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qfalse;
break;
case OP_SUBF:
InstImm( PPC_LFS, R_TOP, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_LFSU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_FSUBS, R_TOP, R_SECOND, R_TOP );
InstImm( PPC_STFS, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qfalse;
break;
case OP_DIVF:
InstImm( PPC_LFS, R_TOP, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_LFSU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst( PPC_FDIVS, R_TOP, R_SECOND, R_TOP );
InstImm( PPC_STFS, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qfalse;
break;
case OP_MULF:
InstImm( PPC_LFS, R_TOP, R_OPSTACK, 0 ); // get value from opstack
InstImm( PPC_LFSU, R_SECOND, R_OPSTACK, -4 ); // get value from opstack
Inst4( PPC_FMULS, R_TOP, R_SECOND, 0, R_TOP );
InstImm( PPC_STFS, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qfalse;
break;
case OP_CVIF:
v = (int)&itofConvert;
InstImmU( PPC_ADDIS, R_EA, 0, (v >> 16)&0xffff );
InstImmU( PPC_ORI, R_EA, R_EA, v & 0xffff );
InstImm( PPC_LWZ, R_TOP, R_OPSTACK, 0 ); // get value from opstack
InstImmU( PPC_XORIS, R_TOP, R_TOP, 0x8000 );
InstImm( PPC_STW, R_TOP, R_EA, 12 );
InstImm( PPC_LFD, R_TOP, R_EA, 0 );
InstImm( PPC_LFD, R_SECOND, R_EA, 8 );
Inst( PPC_FSUB, R_TOP, R_SECOND, R_TOP );
// Inst( PPC_FRSP, R_TOP, 0, R_TOP );
InstImm( PPC_STFS, R_TOP, R_OPSTACK, 0 ); // save value to opstack
rtopped = qfalse;
break;
case OP_CVFI:
InstImm( PPC_LFS, R_TOP, R_OPSTACK, 0 ); // get value from opstack
Inst( PPC_FCTIWZ, R_TOP, 0, R_TOP );
Inst( PPC_STFIWX, R_TOP, 0, R_OPSTACK ); // save value to opstack
rtopped = qfalse;
break;
case OP_SEX8:
ltop(); // get value from opstack
Inst( PPC_EXTSB, R_TOP, R_TOP, 0 );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 );
rtopped = qtrue;
break;
case OP_SEX16:
ltop(); // get value from opstack
Inst( PPC_EXTSH, R_TOP, R_TOP, 0 );
InstImm( PPC_STW, R_TOP, R_OPSTACK, 0 );
rtopped = qtrue;
break;
case OP_BLOCK_COPY:
v = Constant4() >> 2;
ltop(); // source
InstImm( PPC_LWZ, R_SECOND, R_OPSTACK, -4 ); // dest
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -8 );
InstImmU( PPC_ADDI, R_EA, 0, v ); // count
// FIXME: range check
Inst( PPC_MTSPR, R_EA, 9, 0 ); // move to count register
Inst( PPC_ADD, R_TOP, R_TOP, R_MEMBASE );
InstImm( PPC_ADDI, R_TOP, R_TOP, -4 );
Inst( PPC_ADD, R_SECOND, R_SECOND, R_MEMBASE );
InstImm( PPC_ADDI, R_SECOND, R_SECOND, -4 );
InstImm( PPC_LWZU, R_EA, R_TOP, 4 ); // source
InstImm( PPC_STWU, R_EA, R_SECOND, 4 ); // dest
Inst( PPC_BC | 0xfff8 , 16, 0, 0 ); // loop
rtopped = qfalse;
break;
case OP_JUMP:
ltop(); // get value from opstack
InstImm( PPC_ADDI, R_OPSTACK, R_OPSTACK, -4 );
Inst( PPC_RLWINM | ( 29 << 1 ), R_TOP, R_TOP, 2 );
// FIXME: range check
Inst( PPC_LWZX, R_TOP, R_TOP, R_INSTRUCTIONS );
Inst( PPC_MTSPR, R_TOP, 9, 0 ); // move to count register
Inst( PPC_BCCTR, 20, 0, 0 ); // jump to the count register
rtopped = qfalse;
break;
default:
Com_Error( ERR_DROP, "VM_CompilePPC: bad opcode %i at instruction %i, offset %i", op, instruction, pc );
}
pop0 = pop1;
pop1 = op;
}
Com_Printf( "VM file %s pass %d compiled to %i bytes of code\n", vm->name, (pass+1), compiledOfs*4 );
if ( pass == 0 ) {
// copy to an exact size buffer on the hunk
vm->codeLength = compiledOfs * 4;
vm->codeBase = Hunk_Alloc( vm->codeLength, h_low );
Com_Memcpy( vm->codeBase, buf, vm->codeLength );
Z_Free( buf );
// offset all the instruction pointers for the new location
for ( i = 0 ; i < header->instructionCount ; i++ ) {
vm->instructionPointers[i] += (int)vm->codeBase;
}
// go back over it in place now to fixup reletive jump targets
buf = (unsigned *)vm->codeBase;
}
}
Z_Free( jused );
}
/*
==============
VM_CallCompiled
This function is called directly by the generated code
==============
*/
int VM_CallCompiled( vm_t *vm, int *args ) {
int stack[1024];
int programStack;
int stackOnEntry;
byte *image;
currentVM = vm;
// interpret the code
vm->currentlyInterpreting = qtrue;
// we might be called recursively, so this might not be the very top
programStack = vm->programStack;
stackOnEntry = programStack;
image = vm->dataBase;
// set up the stack frame
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...
// the PPC calling standard says the parms will all go into R3 - R11, so
// no special asm code is needed here
#ifdef __GNUC__
((void(*)(int, int, int, int, int, int, int, int))(vm->codeBase))(
programStack, (int)&stack,
(int)image, vm->dataMask, (int)&AsmCall,
(int)vm->instructionPointers, vm->instructionPointersLength,
(int)vm );
#else
((void(*)(int, int, int, int, int, int, int, int))(vm->codeBase))(
programStack, (int)&stack,
(int)image, vm->dataMask, *(int *)&AsmCall /* skip function pointer header */,
(int)vm->instructionPointers, vm->instructionPointersLength,
(int)vm );
#endif
vm->programStack = stackOnEntry;
vm->currentlyInterpreting = qfalse;
return stack[1];
}
/*
==================
AsmCall
Put this at end of file because gcc messes up debug line numbers
==================
*/
#ifdef __GNUC__
void AsmCall( void ) {
asm ("
// pop off the destination instruction
lwz r12,0(r4) // RG_TOP, 0(RG_OPSTACK)
addi r4,r4,-4 // RG_OPSTACK, RG_OPSTACK, -4
// see if it is a system trap
cmpwi r12,0 // RG_TOP, 0
bc 12,0, systemTrap
// calling another VM function, so lookup in instructionPointers
slwi r12,r12,2 // RG_TOP,RG_TOP,2
// FIXME: range check
lwzx r12, r8, r12 // RG_TOP, RG_INSTRUCTIONS(RG_TOP)
mtctr r12 // RG_TOP
");
#if defined(MACOS_X) && defined(__OPTIMIZE__)
// On Mac OS X, gcc doesn't push a frame when we are optimized, so trying to tear it down results in grave disorder.
#warning Mac OS X optimization on, not popping GCC AsmCall frame
#else
// Mac OS X Server and unoptimized compiles include a GCC AsmCall frame
asm ("
lwz r1,0(r1) // pop off the GCC AsmCall frame
lmw r30,-8(r1)
");
#endif
asm ("
bcctr 20,0 // when it hits a leave, it will branch to the current link register
// calling a system trap
systemTrap:
// convert to positive system call number
subfic r12,r12,-1
// save all our registers, including the current link register
mflr r13 // RG_SECOND // copy off our link register
addi r1,r1,-92 // required 24 byets of linkage, 32 bytes of parameter, plus our saves
stw r3,56(r1) // RG_STACK, -36(REAL_STACK)
stw r4,60(r1) // RG_OPSTACK, 4(RG_REAL_STACK)
stw r5,64(r1) // RG_MEMBASE, 8(RG_REAL_STACK)
stw r6,68(r1) // RG_MEMMASK, 12(RG_REAL_STACK)
stw r7,72(r1) // RG_ASMCALL, 16(RG_REAL_STACK)
stw r8,76(r1) // RG_INSTRUCTIONS, 20(RG_REAL_STACK)
stw r9,80(r1) // RG_NUM_INSTRUCTIONS, 24(RG_REAL_STACK)
stw r10,84(r1) // RG_VM, 28(RG_REAL_STACK)
stw r13,88(r1) // RG_SECOND, 32(RG_REAL_STACK) // link register
// save the vm stack position to allow recursive VM entry
addi r13,r3,-4 // RG_TOP, RG_STACK, -4
stw r13,0(r10) //RG_TOP, VM_OFFSET_PROGRAM_STACK(RG_VM)
// save the system call number as the 0th parameter
add r3,r3,r5 // r3, RG_STACK, RG_MEMBASE // r3 is the first parameter to vm->systemCalls
stwu r12,4(r3) // RG_TOP, 4(r3)
// make the system call with the address of all the VM parms as a parameter
// vm->systemCalls( &parms )
lwz r12,4(r10) // RG_TOP, VM_OFFSET_SYSTEM_CALL(RG_VM)
mtctr r12 // RG_TOP
bcctrl 20,0
mr r12,r3 // RG_TOP, r3
// pop our saved registers
lwz r3,56(r1) // RG_STACK, 0(RG_REAL_STACK)
lwz r4,60(r1) // RG_OPSTACK, 4(RG_REAL_STACK)
lwz r5,64(r1) // RG_MEMBASE, 8(RG_REAL_STACK)
lwz r6,68(r1) // RG_MEMMASK, 12(RG_REAL_STACK)
lwz r7,72(r1) // RG_ASMCALL, 16(RG_REAL_STACK)
lwz r8,76(r1) // RG_INSTRUCTIONS, 20(RG_REAL_STACK)
lwz r9,80(r1) // RG_NUM_INSTRUCTIONS, 24(RG_REAL_STACK)
lwz r10,84(r1) // RG_VM, 28(RG_REAL_STACK)
lwz r13,88(r1) // RG_SECOND, 32(RG_REAL_STACK)
addi r1,r1,92 // RG_REAL_STACK, RG_REAL_STACK, 36
// restore the old link register
mtlr r13 // RG_SECOND
// save off the return value
stwu r12,4(r4) // RG_TOP, 0(RG_OPSTACK)
// GCC adds its own prolog / epliog code
" );
}
#endif