--- /dev/null
+// Copyright 2003 Brian Alliet
+// Based on org.xwt.imp.MIPS by Adam Megacz
+// Portions Copyright 2003 Adam Megacz
+
+package org.ibex.nestedvm;
+
+import org.ibex.nestedvm.util.*;
+import java.io.*;
+
+public class Interpreter extends UnixRuntime {
+ // Registers
+ private int[] registers = new int[32];
+ private int hi,lo;
+
+ // Floating Point Registers
+ private int[] fpregs = new int[32];
+ // 24-31 - unused
+ // 23 - conditional bit
+ // 18-22 - unused
+ // 12-17 - cause bits (unimplemented)
+ // 7-11 - enables bits (unimplemented)
+ // 2-6 - flags (unimplemented)
+ // 0-1 - rounding mode (only implemented for fixed point conversions)
+ private int fcsr;
+
+ private int pc;
+
+ // The filename if the binary we're running
+ public String image;
+ private ELF.Symtab symtab;
+
+ // Register Operations
+ private final void setFC(boolean b) { fcsr = (fcsr&~0x800000) | (b ? 0x800000 : 0x000000); }
+ private final int roundingMode() { return fcsr & 3; /* bits 0-1 */ }
+ private final double getDouble(int r) {
+ return Double.longBitsToDouble(((fpregs[r+1]&0xffffffffL) << 32) | (fpregs[r]&0xffffffffL));
+ }
+ private final void setDouble(int r, double d) {
+ long l = Double.doubleToLongBits(d);
+ fpregs[r+1] = (int)(l >>> 32); fpregs[r] = (int)l;
+ }
+ private final float getFloat(int r) { return Float.intBitsToFloat(fpregs[r]); }
+ private final void setFloat(int r, float f) { fpregs[r] = Float.floatToRawIntBits(f); }
+
+ protected void _execute() throws ExecutionException {
+ try {
+ runSome();
+ } catch(ExecutionException e) {
+ e.setLocation(toHex(pc) + ": " + sourceLine(pc));
+ throw e;
+ }
+ }
+
+ // Main interpretor
+ // the return value is meaningless, its just to catch people typing "return" by accident
+ private final int runSome() throws FaultException,ExecutionException {
+ int[] r = registers;
+ int[] f = fpregs;
+ int pc = this.pc;
+ int nextPC = pc + 4;
+ try {
+ OUTER: for(;;) {
+ int insn;
+ try {
+ insn = readPages[pc>>>PAGE_SHIFT][(pc>>>2)&PAGE_WORDS-1];
+ } catch (RuntimeException e) {
+ insn = memRead(pc);
+ }
+
+ int op = (insn >>> 26) & 0xff; // bits 26-31
+ int rs = (insn >>> 21) & 0x1f; // bits 21-25
+ int rt = (insn >>> 16) & 0x1f; // bits 16-20
+ int ft = (insn >>> 16) & 0x1f;
+ int rd = (insn >>> 11) & 0x1f; // bits 11-15
+ int fs = (insn >>> 11) & 0x1f;
+ int shamt = (insn >>> 6) & 0x1f; // bits 6-10
+ int fd = (insn >>> 6) & 0x1f;
+ int subcode = insn & 0x3f; // bits 0-5
+
+ int jumpTarget = (insn & 0x03ffffff); // bits 0-25
+ int unsignedImmediate = insn & 0xffff;
+ int signedImmediate = (insn << 16) >> 16;
+ int branchTarget = signedImmediate;
+
+ int tmp, addr; // temporaries
+
+ r[ZERO] = 0;
+
+ switch(op) {
+ case 0: {
+ switch(subcode) {
+ case 0: // SLL
+ if(insn == 0) break;
+ r[rd] = r[rt] << shamt;
+ break;
+ case 2: // SRL
+ r[rd] = r[rt] >>> shamt;
+ break;
+ case 3: // SRA
+ r[rd] = r[rt] >> shamt;
+ break;
+ case 4: // SLLV
+ r[rd] = r[rt] << (r[rs]&0x1f);
+ break;
+ case 6: // SRLV
+ r[rd] = r[rt] >>> (r[rs]&0x1f);
+ break;
+ case 7: // SRAV
+ r[rd] = r[rt] >> (r[rs]&0x1f);
+ break;
+ case 8: // JR
+ tmp = r[rs]; pc += 4; nextPC = tmp;
+ continue OUTER;
+ case 9: // JALR
+ tmp = r[rs]; pc += 4; r[rd] = pc+4; nextPC = tmp;
+ continue OUTER;
+ case 12: // SYSCALL
+ this.pc = pc;
+ r[V0] = syscall(r[V0],r[A0],r[A1],r[A2],r[A3]);
+ if(state != RUNNING) { this.pc = nextPC; break OUTER; }
+ break;
+ case 13: // BREAK
+ throw new ExecutionException("Break");
+ case 16: // MFHI
+ r[rd] = hi;
+ break;
+ case 17: // MTHI
+ hi = r[rs];
+ break;
+ case 18: // MFLO
+ r[rd] = lo;
+ break;
+ case 19: // MTLO
+ lo = r[rs];
+ break;
+ case 24: { // MULT
+ long hilo = (long)(r[rs]) * ((long)r[rt]);
+ hi = (int) (hilo >>> 32);
+ lo = (int) hilo;
+ break;
+ }
+ case 25: { // MULTU
+ long hilo = (r[rs] & 0xffffffffL) * (r[rt] & 0xffffffffL);
+ hi = (int) (hilo >>> 32);
+ lo = (int) hilo;
+ break;
+ }
+ case 26: // DIV
+ hi = r[rs]%r[rt];
+ lo = r[rs]/r[rt];
+ break;
+ case 27: // DIVU
+ if(rt != 0) {
+ hi = (int)((r[rs] & 0xffffffffL) % (r[rt] & 0xffffffffL));
+ lo = (int)((r[rs] & 0xffffffffL) / (r[rt] & 0xffffffffL));
+ }
+ break;
+ case 32: // ADD
+ throw new ExecutionException("ADD (add with oveflow trap) not suported");
+ /*This must trap on overflow
+ r[rd] = r[rs] + r[rt];
+ break;*/
+ case 33: // ADDU
+ r[rd] = r[rs] + r[rt];
+ break;
+ case 34: // SUB
+ throw new ExecutionException("SUB (sub with oveflow trap) not suported");
+ /*This must trap on overflow
+ r[rd] = r[rs] - r[rt];
+ break;*/
+ case 35: // SUBU
+ r[rd] = r[rs] - r[rt];
+ break;
+ case 36: // AND
+ r[rd] = r[rs] & r[rt];
+ break;
+ case 37: // OR
+ r[rd] = r[rs] | r[rt];
+ break;
+ case 38: // XOR
+ r[rd] = r[rs] ^ r[rt];
+ break;
+ case 39: // NOR
+ r[rd] = ~(r[rs] | r[rt]);
+ break;
+ case 42: // SLT
+ r[rd] = r[rs] < r[rt] ? 1 : 0;
+ break;
+ case 43: // SLTU
+ r[rd] = ((r[rs] & 0xffffffffL) < (r[rt] & 0xffffffffL)) ? 1 : 0;
+ break;
+ default:
+ throw new ExecutionException("Illegal instruction 0/" + subcode);
+ }
+ break;
+ }
+ case 1: {
+ switch(rt) {
+ case 0: // BLTZ
+ if(r[rs] < 0) {
+ pc += 4; tmp = pc + branchTarget*4; nextPC = tmp;
+ continue OUTER;
+ }
+ break;
+ case 1: // BGEZ
+ if(r[rs] >= 0) {
+ pc += 4; tmp = pc + branchTarget*4; nextPC = tmp;
+ continue OUTER;
+ }
+ break;
+ case 16: // BLTZAL
+ if(r[rs] < 0) {
+ pc += 4; r[RA] = pc+4; tmp = pc + branchTarget*4; nextPC = tmp;
+ continue OUTER;
+ }
+ break;
+ case 17: // BGEZAL
+ if(r[rs] >= 0) {
+ pc += 4; r[RA] = pc+4; tmp = pc + branchTarget*4; nextPC = tmp;
+ continue OUTER;
+ }
+ break;
+ default:
+ throw new ExecutionException("Illegal Instruction");
+ }
+ break;
+ }
+ case 2: { // J
+ tmp = (pc&0xf0000000) | (jumpTarget << 2);
+ pc+=4; nextPC = tmp;
+ continue OUTER;
+ }
+ case 3: { // JAL
+ tmp = (pc&0xf0000000) | (jumpTarget << 2);
+ pc+=4; r[RA] = pc+4; nextPC = tmp;
+ continue OUTER;
+ }
+ case 4: // BEQ
+ if(r[rs] == r[rt]) {
+ pc += 4; tmp = pc + branchTarget*4; nextPC = tmp;
+ continue OUTER;
+ }
+ break;
+ case 5: // BNE
+ if(r[rs] != r[rt]) {
+ pc += 4; tmp = pc + branchTarget*4; nextPC = tmp;
+ continue OUTER;
+ }
+ break;
+ case 6: //BLEZ
+ if(r[rs] <= 0) {
+ pc += 4; tmp = pc + branchTarget*4; nextPC = tmp;
+ continue OUTER;
+ }
+ break;
+ case 7: //BGTZ
+ if(r[rs] > 0) {
+ pc += 4; tmp = pc + branchTarget*4; nextPC = tmp;
+ continue OUTER;
+ }
+ break;
+ case 8: // ADDI
+ r[rt] = r[rs] + signedImmediate;
+ break;
+ case 9: // ADDIU
+ r[rt] = r[rs] + signedImmediate;
+ break;
+ case 10: // SLTI
+ r[rt] = r[rs] < signedImmediate ? 1 : 0;
+ break;
+ case 11: // SLTIU
+ r[rt] = (r[rs]&0xffffffffL) < (unsignedImmediate&0xffffffffL) ? 1 : 0;
+ break;
+ case 12: // ANDI
+ r[rt] = r[rs] & unsignedImmediate;
+ break;
+ case 13: // ORI
+ r[rt] = r[rs] | unsignedImmediate;
+ break;
+ case 14: // XORI
+ r[rt] = r[rs] ^ unsignedImmediate;
+ break;
+ case 15: // LUI
+ r[rt] = unsignedImmediate << 16;
+ break;
+ case 16:
+ throw new ExecutionException("TLB/Exception support not implemented");
+ case 17: { // FPU
+ boolean debug = false;
+ String line = debug ? sourceLine(pc) : "";
+ boolean debugon = debug && (line.indexOf("dtoa.c:51") >= 0 || line.indexOf("dtoa.c:52") >= 0 || line.indexOf("test.c") >= 0);
+ if(rs > 8 && debugon)
+ System.out.println(" FP Op: " + op + "/" + rs + "/" + subcode + " " + line);
+ if(roundingMode() != 0 && rs != 6 /*CTC.1*/ && !((rs==16 || rs==17) && subcode == 36 /* CVT.W.Z */))
+ throw new ExecutionException("Non-cvt.w.z operation attempted with roundingMode != round to nearest");
+ switch(rs) {
+ case 0: // MFC.1
+ r[rt] = f[rd];
+ break;
+ case 2: // CFC.1
+ if(fs != 31) throw new ExecutionException("FCR " + fs + " unavailable");
+ r[rt] = fcsr;
+ break;
+ case 4: // MTC.1
+ f[rd] = r[rt];
+ break;
+ case 6: // CTC.1
+ if(fs != 31) throw new ExecutionException("FCR " + fs + " unavailable");
+ fcsr = r[rt];
+ break;
+ case 8: // BC1F, BC1T
+ if(((fcsr&0x800000)!=0) == (((insn>>>16)&1)!=0)) {
+ pc += 4; tmp = pc + branchTarget*4; nextPC = tmp;
+ continue OUTER;
+ }
+ break;
+ case 16: { // Single
+ switch(subcode) {
+ case 0: // ADD.S
+ setFloat(fd,getFloat(fs)+getFloat(ft));
+ break;
+ case 1: // SUB.S
+ setFloat(fd,getFloat(fs)-getFloat(ft));
+ break;
+ case 2: // MUL.S
+ setFloat(fd,getFloat(fs)*getFloat(ft));
+ break;
+ case 3: // DIV.S
+ setFloat(fd,getFloat(fs)/getFloat(ft));
+ break;
+ case 5: // ABS.S
+ setFloat(fd,Math.abs(getFloat(fs)));
+ break;
+ case 6: // MOV.S
+ f[fd] = f[fs];
+ break;
+ case 7: // NEG.S
+ setFloat(fd,-getFloat(fs));
+ break;
+ case 33: // CVT.D.S
+ setDouble(fd,getFloat(fs));
+ break;
+ case 36: // CVT.W.S
+ switch(roundingMode()) {
+ case 0: f[fd] = (int)Math.floor(getFloat(fs)+0.5f); break; // Round to nearest
+ case 1: f[fd] = (int)getFloat(fs); break; // Round towards zero
+ case 2: f[fd] = (int)Math.ceil(getFloat(fs)); break; // Round towards plus infinity
+ case 3: f[fd] = (int)Math.floor(getFloat(fs)); break; // Round towards minus infinity
+ }
+ break;
+ case 50: // C.EQ.S
+ setFC(getFloat(fs) == getFloat(ft));
+ break;
+ case 60: // C.LT.S
+ setFC(getFloat(fs) < getFloat(ft));
+ break;
+ default: throw new ExecutionException("Invalid Instruction 17/" + rs + "/" + subcode + " at " + sourceLine(pc));
+ }
+ break;
+ }
+ case 17: { // Double
+ switch(subcode) {
+ case 0: // ADD.D
+ setDouble(fd,getDouble(fs)+getDouble(ft));
+ break;
+ case 1: // SUB.D
+ if(debugon) System.out.println("f" + fd + " = f" + fs + " (" + getDouble(fs) + ") - f" + ft + " (" + getDouble(ft) + ")");
+ setDouble(fd,getDouble(fs)-getDouble(ft));
+ break;
+ case 2: // MUL.D
+ if(debugon) System.out.println("f" + fd + " = f" + fs + " (" + getDouble(fs) + ") * f" + ft + " (" + getDouble(ft) + ")");
+ setDouble(fd,getDouble(fs)*getDouble(ft));
+ if(debugon) System.out.println("f" + fd + " = " + getDouble(fd));
+ break;
+ case 3: // DIV.D
+ setDouble(fd,getDouble(fs)/getDouble(ft));
+ break;
+ case 5: // ABS.D
+ setDouble(fd,Math.abs(getDouble(fs)));
+ break;
+ case 6: // MOV.D
+ f[fd] = f[fs];
+ f[fd+1] = f[fs+1];
+ break;
+ case 7: // NEG.D
+ setDouble(fd,-getDouble(fs));
+ break;
+ case 32: // CVT.S.D
+ setFloat(fd,(float)getDouble(fs));
+ break;
+ case 36: // CVT.W.D
+ if(debugon) System.out.println("CVT.W.D rm: " + roundingMode() + " f" + fs + ":" + getDouble(fs));
+ switch(roundingMode()) {
+ case 0: f[fd] = (int)Math.floor(getDouble(fs)+0.5); break; // Round to nearest
+ case 1: f[fd] = (int)getDouble(fs); break; // Round towards zero
+ case 2: f[fd] = (int)Math.ceil(getDouble(fs)); break; // Round towards plus infinity
+ case 3: f[fd] = (int)Math.floor(getDouble(fs)); break; // Round towards minus infinity
+ }
+ if(debugon) System.out.println("CVT.W.D: f" + fd + ":" + f[fd]);
+ break;
+ case 50: // C.EQ.D
+ setFC(getDouble(fs) == getDouble(ft));
+ break;
+ case 60: // C.LT.D
+ setFC(getDouble(fs) < getDouble(ft));
+ break;
+ case 62: // C.LE.D
+ setFC(getDouble(fs) <= getDouble(ft));
+ break;
+ default: throw new ExecutionException("Invalid Instruction 17/" + rs + "/" + subcode + " at " + sourceLine(pc));
+ }
+ break;
+ }
+ case 20: { // Integer
+ switch(subcode) {
+ case 33: // CVT.D.W
+ setDouble(fd,f[fs]);
+ break;
+ default: throw new ExecutionException("Invalid Instruction 17/" + rs + "/" + subcode + " at " + sourceLine(pc));
+ }
+ break;
+ }
+ default:
+ throw new ExecutionException("Invalid Instruction 17/" + rs);
+ }
+ break;
+ }
+ case 18: case 19:
+ throw new ExecutionException("No coprocessor installed");
+ case 32: { // LB
+ addr = r[rs] + signedImmediate;
+ try {
+ tmp = readPages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)];
+ } catch(RuntimeException e) {
+ tmp = memRead(addr&~3);
+ }
+ switch(addr&3) {
+ case 0: tmp = (tmp>>>24)&0xff; break;
+ case 1: tmp = (tmp>>>16)&0xff; break;
+ case 2: tmp = (tmp>>> 8)&0xff; break;
+ case 3: tmp = (tmp>>> 0)&0xff; break;
+ }
+ if((tmp&0x80)!=0) tmp |= 0xffffff00; // sign extend
+ r[rt] = tmp;
+ break;
+ }
+ case 33: { // LH
+ addr = r[rs] + signedImmediate;
+ try {
+ tmp = readPages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)];
+ } catch(RuntimeException e) {
+ tmp = memRead(addr&~3);
+ }
+ switch(addr&2) {
+ case 0: tmp = (tmp>>>16)&0xffff; break;
+ case 2: tmp = (tmp>>> 0)&0xffff; break;
+ }
+ if((tmp&0x8000)!=0) tmp |= 0xffff0000; // sign extend
+ r[rt] = tmp;
+ break;
+ }
+ case 34: { // LWL;
+ addr = r[rs] + signedImmediate;
+ try {
+ tmp = readPages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)];
+ } catch(RuntimeException e) {
+ tmp = memRead(addr&~3);
+ }
+ switch(addr&3) {
+ case 0: r[rt] = (r[rt]&0x00000000)|(tmp<< 0); break;
+ case 1: r[rt] = (r[rt]&0x000000ff)|(tmp<< 8); break;
+ case 2: r[rt] = (r[rt]&0x0000ffff)|(tmp<<16); break;
+ case 3: r[rt] = (r[rt]&0x00ffffff)|(tmp<<24); break;
+ }
+ break;
+ }
+ case 35: // LW
+ addr = r[rs] + signedImmediate;
+ try {
+ r[rt] = readPages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)];
+ } catch(RuntimeException e) {
+ r[rt] = memRead(addr);
+ }
+ break;
+ case 36: { // LBU
+ addr = r[rs] + signedImmediate;
+ try {
+ tmp = readPages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)];
+ } catch(RuntimeException e) {
+ tmp = memRead(addr);
+ }
+ switch(addr&3) {
+ case 0: r[rt] = (tmp>>>24)&0xff; break;
+ case 1: r[rt] = (tmp>>>16)&0xff; break;
+ case 2: r[rt] = (tmp>>> 8)&0xff; break;
+ case 3: r[rt] = (tmp>>> 0)&0xff; break;
+ }
+ break;
+ }
+ case 37: { // LHU
+ addr = r[rs] + signedImmediate;
+ try {
+ tmp = readPages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)];
+ } catch(RuntimeException e) {
+ tmp = memRead(addr&~3);
+ }
+ switch(addr&2) {
+ case 0: r[rt] = (tmp>>>16)&0xffff; break;
+ case 2: r[rt] = (tmp>>> 0)&0xffff; break;
+ }
+ break;
+ }
+ case 38: { // LWR
+ addr = r[rs] + signedImmediate;
+ try {
+ tmp = readPages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)];
+ } catch(RuntimeException e) {
+ tmp = memRead(addr&~3);
+ }
+ switch(addr&3) {
+ case 0: r[rt] = (r[rt]&0xffffff00)|(tmp>>>24); break;
+ case 1: r[rt] = (r[rt]&0xffff0000)|(tmp>>>16); break;
+ case 2: r[rt] = (r[rt]&0xff000000)|(tmp>>> 8); break;
+ case 3: r[rt] = (r[rt]&0x00000000)|(tmp>>> 0); break;
+ }
+ break;
+ }
+ case 40: { // SB
+ addr = r[rs] + signedImmediate;
+ try {
+ tmp = readPages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)];
+ } catch(RuntimeException e) {
+ tmp = memRead(addr&~3);
+ }
+ switch(addr&3) {
+ case 0: tmp = (tmp&0x00ffffff) | ((r[rt]&0xff)<<24); break;
+ case 1: tmp = (tmp&0xff00ffff) | ((r[rt]&0xff)<<16); break;
+ case 2: tmp = (tmp&0xffff00ff) | ((r[rt]&0xff)<< 8); break;
+ case 3: tmp = (tmp&0xffffff00) | ((r[rt]&0xff)<< 0); break;
+ }
+ try {
+ writePages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)] = tmp;
+ } catch(RuntimeException e) {
+ memWrite(addr&~3,tmp);
+ }
+ break;
+ }
+ case 41: { // SH
+ addr = r[rs] + signedImmediate;
+ try {
+ tmp = readPages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)];
+ } catch(RuntimeException e) {
+ tmp = memRead(addr&~3);
+ }
+ switch(addr&2) {
+ case 0: tmp = (tmp&0x0000ffff) | ((r[rt]&0xffff)<<16); break;
+ case 2: tmp = (tmp&0xffff0000) | ((r[rt]&0xffff)<< 0); break;
+ }
+ try {
+ writePages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)] = tmp;
+ } catch(RuntimeException e) {
+ memWrite(addr&~3,tmp);
+ }
+ break;
+ }
+ case 42: { // SWL
+ addr = r[rs] + signedImmediate;
+ tmp = memRead(addr&~3);
+ switch(addr&3) {
+ case 0: tmp=(tmp&0x00000000)|(r[rt]>>> 0); break;
+ case 1: tmp=(tmp&0xff000000)|(r[rt]>>> 8); break;
+ case 2: tmp=(tmp&0xffff0000)|(r[rt]>>>16); break;
+ case 3: tmp=(tmp&0xffffff00)|(r[rt]>>>24); break;
+ }
+ try {
+ writePages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)] = tmp;
+ } catch(RuntimeException e) {
+ memWrite(addr&~3,tmp);
+ }
+ break;
+ }
+ case 43: // SW
+ addr = r[rs] + signedImmediate;
+ try {
+ writePages[addr>>>PAGE_SHIFT][(addr>>>2)&(PAGE_WORDS-1)] = r[rt];
+ } catch(RuntimeException e) {
+ memWrite(addr&~3,r[rt]);
+ }
+ break;
+ case 46: { // SWR
+ addr = r[rs] + signedImmediate;
+ tmp = memRead(addr&~3);
+ switch(addr&3) {
+ case 0: tmp=(tmp&0x00ffffff)|(r[rt]<<24); break;
+ case 1: tmp=(tmp&0x0000ffff)|(r[rt]<<16); break;
+ case 2: tmp=(tmp&0x000000ff)|(r[rt]<< 8); break;
+ case 3: tmp=(tmp&0x00000000)|(r[rt]<< 0); break;
+ }
+ memWrite(addr&~3,tmp);
+ break;
+ }
+ // FEATURE: Needs to be atomic w/ threads
+ case 48: // LWC0/LL
+ r[rt] = memRead(r[rs] + signedImmediate);
+ break;
+ case 49: // LWC1
+ f[rt] = memRead(r[rs] + signedImmediate);
+ break;
+ // FEATURE: Needs to be atomic w/ threads
+ case 56:
+ memWrite(r[rs] + signedImmediate,r[rt]);
+ r[rt] = 1;
+ break;
+ case 57: // SWC1
+ memWrite(r[rs] + signedImmediate,f[rt]);
+ break;
+ default:
+ throw new ExecutionException("Invalid Instruction: " + op);
+ }
+ pc = nextPC;
+ nextPC = pc + 4;
+ } // for(;;)
+ } catch(ExecutionException e) {
+ this.pc = pc;
+ throw e;
+ }
+ return 0;
+ }
+
+ public int lookupSymbol(String name) {
+ ELF.Symbol sym = symtab.getGlobalSymbol(name);
+ return sym == null ? -1 : sym.addr;
+ }
+
+ // Image loading function
+ private void loadImage(Seekable data) throws IOException {
+ if(state != UNINITIALIZED) throw new IllegalStateException("loadImage called on initialized runtime");
+
+ ELF elf = new ELF(data);
+ symtab = elf.getSymtab();
+
+ if(elf.header.type != ELF.ELFHeader.ET_EXEC) throw new IOException("Binary is not an executable");
+ if(elf.header.machine != ELF.ELFHeader.EM_MIPS) throw new IOException("Binary is not for the MIPS I Architecture");
+ if(elf.ident.data != ELF.ELFIdent.ELFDATA2MSB) throw new IOException("Binary is not big endian");
+
+ entryPoint = elf.header.entry;
+
+ ELF.Symtab symtab = elf.getSymtab();
+ if(symtab == null) throw new IOException("No symtab in binary (did you strip it?)");
+ ELF.Symbol userInfo = symtab.getGlobalSymbol("user_info");
+ ELF.Symbol gpsym = symtab.getGlobalSymbol("_gp");
+
+ if(gpsym == null) throw new IOException("NO _gp symbol!");
+ gp = gpsym.addr;
+
+ if(userInfo != null) {
+ userInfoBase = userInfo.addr;
+ userInfoSize = userInfo.size;
+ }
+
+ ELF.PHeader[] pheaders = elf.pheaders;
+ int brk = 0;
+ for(int i=0;i<pheaders.length;i++) {
+ ELF.PHeader ph = pheaders[i];
+ if(ph.type != ELF.PHeader.PT_LOAD) continue;
+ int memsize = ph.memsz;
+ int filesize = ph.filesz;
+ if(memsize == 0) continue;
+ if(memsize < 0) throw new IOException("pheader size too large");
+ int addr = ph.vaddr;
+ if(addr == 0x0) throw new IOException("pheader vaddr == 0x0");
+ brk = max(addr+memsize,brk);
+
+ for(int j=0;j<memsize+PAGE_SIZE-1;j+=PAGE_SIZE) {
+ int page = (j+addr) >>> PAGE_SHIFT;
+ if(readPages[page] == null)
+ readPages[page] = new int[PAGE_WORDS];
+ if(ph.writable()) writePages[page] = readPages[page];
+ }
+ if(filesize != 0) {
+ filesize = filesize & ~3;
+ DataInputStream dis = new DataInputStream(ph.getInputStream());
+ do {
+ readPages[addr >>> PAGE_SHIFT][(addr >>> 2)&(PAGE_WORDS-1)] = dis.readInt();
+ addr+=4;
+ filesize-=4;
+ } while(filesize > 0);
+ dis.close();
+ }
+ }
+ brkAddr = (brk+PAGE_SIZE-1)&~(PAGE_SIZE-1);
+ state = INITIALIZED;
+ }
+
+ protected void setCPUState(CPUState state) {
+ for(int i=1;i<32;i++) registers[i] = state.r[i];
+ for(int i=0;i<32;i++) fpregs[i] = state.f[i];
+ hi=state.hi; lo=state.lo; fcsr=state.fcsr;
+ pc=state.pc;
+ }
+
+ protected CPUState getCPUState() {
+ CPUState state = new CPUState();
+ for(int i=1;i<32;i++) state.r[i] = registers[i];
+ for(int i=0;i<32;i++) state.f[i] = fpregs[i];
+ state.hi=hi; state.lo=lo; state.fcsr=fcsr;
+ state.pc=pc;
+ return state;
+ }
+
+ // This is package private for fork() which does all kinds of ugly things behind the scenes
+ Interpreter() { super(4096,65536,true); }
+ public Interpreter(Seekable data) throws IOException { this(); loadImage(data); }
+ public Interpreter(String filename) throws IOException {
+ this(new Seekable.File(filename,false));
+ image = filename;
+ }
+ public Interpreter(InputStream is) throws IOException { this(new Seekable.InputStream(is)); }
+
+ // Debug functions
+ // NOTE: This probably requires a jdk > 1.1, however, it is only used for debugging
+ private java.util.HashMap sourceLineCache;
+ public String sourceLine(int pc) {
+ final String addr2line = "mips-unknown-elf-addr2line";
+ String line = (String) (sourceLineCache == null ? null : sourceLineCache.get(new Integer(pc)));
+ if(line != null) return line;
+ if(image==null) return null;
+ try {
+ Process p = java.lang.Runtime.getRuntime().exec(new String[]{addr2line,"-e",image,toHex(pc)});
+ line = new BufferedReader(new InputStreamReader(p.getInputStream())).readLine();
+ if(line == null) return null;
+ while(line.startsWith("../")) line = line.substring(3);
+ if(sourceLineCache == null) sourceLineCache = new java.util.HashMap();
+ sourceLineCache.put(new Integer(pc),line);
+ return line;
+ } catch(IOException e) {
+ return null;
+ }
+ }
+
+ public class DebugShutdownHook implements Runnable {
+ public void run() {
+ int pc = Interpreter.this.pc;
+ if(getState() == RUNNING)
+ System.err.print("\nCPU Executing " + toHex(pc) + ": " + sourceLine(pc) + "\n");
+ }
+ }
+
+ public static void main(String[] argv) throws Exception {
+ String image = argv[0];
+ Interpreter emu = new Interpreter(image);
+ java.lang.Runtime.getRuntime().addShutdownHook(new Thread(emu.new DebugShutdownHook()));
+ int status = emu.run(argv);
+ System.err.println("Exit status: " + status);
+ System.exit(status);
+ }
+}
projects / nestedvm.git / blobdiff