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Java implementation of 64bit ldiv and lrem bytecodes for 32bit archit…
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…ectures.
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Ian Rogers committed Apr 6, 2009
1 parent dd51336 commit d69b02b
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Showing 10 changed files with 185 additions and 106 deletions.
72 changes: 8 additions & 64 deletions rvm/src/org/jikesrvm/compilers/baseline/ia32/BaselineCompilerImpl.java
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Original file line number Diff line number Diff line change
Expand Up @@ -1164,38 +1164,10 @@ protected final void emit_ldiv() {
asm.emitIDIV_Reg_Reg_Quad(EAX, ECX);
asm.emitPUSH_Reg(EAX); // push result
} else {
// (1) zero check
asm.emitMOV_Reg_RegInd(T0, SP);
asm.emitOR_Reg_RegDisp(T0, SP, ONE_SLOT);
asm.emitBranchLikelyNextInstruction();
ForwardReference fr1 = asm.forwardJcc(Assembler.NE);
asm.emitINT_Imm(RuntimeEntrypoints.TRAP_DIVIDE_BY_ZERO + RVM_TRAP_BASE); // trap if divisor is 0
fr1.resolve(asm);
// (2) save RVM nonvolatiles
int numNonVols = NONVOLATILE_GPRS.length;
Offset off = Offset.fromIntSignExtend(numNonVols * WORDSIZE);
for (int i = 0; i < numNonVols; i++) {
asm.emitPUSH_Reg(NONVOLATILE_GPRS[i]);
}
// (3) Push args to C function (reversed)
asm.emitPUSH_RegDisp(SP, off.plus(4));
asm.emitPUSH_RegDisp(SP, off.plus(4));
asm.emitPUSH_RegDisp(SP, off.plus(20));
asm.emitPUSH_RegDisp(SP, off.plus(20));
// (4) invoke C function through bootrecord
asm.emitMOV_Reg_Abs(S0, Magic.getTocPointer().plus(Entrypoints.the_boot_recordField.getOffset()));
asm.emitCALL_RegDisp(S0, Entrypoints.sysLongDivideIPField.getOffset());
// (5) pop space for arguments
adjustStack(4 * WORDSIZE, true);
// (6) restore RVM nonvolatiles
for (int i = numNonVols - 1; i >= 0; i--) {
asm.emitPOP_Reg(NONVOLATILE_GPRS[i]);
}
// (7) pop expression stack
adjustStack(WORDSIZE*4, true);
// (8) push results
asm.emitPUSH_Reg(T1);
asm.emitPUSH_Reg(T0);
genParameterRegisterLoad(asm, 4); // pass 4 parameter words
asm.emitCALL_Abs(Magic.getTocPointer().plus(Entrypoints.ldivMethod.getOffset()));
asm.emitPUSH_Reg(T0); // high half
asm.emitPUSH_Reg(T1); // low half
}
}

Expand All @@ -1212,38 +1184,10 @@ protected final void emit_lrem() {
asm.emitIDIV_Reg_Reg_Quad(EAX, ECX);
asm.emitPUSH_Reg(EDX); // push result
} else {
// (1) zero check
asm.emitMOV_Reg_RegInd(T0, SP);
asm.emitOR_Reg_RegDisp(T0, SP, ONE_SLOT);
asm.emitBranchLikelyNextInstruction();
ForwardReference fr1 = asm.forwardJcc(Assembler.NE);
asm.emitINT_Imm(RuntimeEntrypoints.TRAP_DIVIDE_BY_ZERO + RVM_TRAP_BASE); // trap if divisor is 0
fr1.resolve(asm);
// (2) save RVM nonvolatiles
int numNonVols = NONVOLATILE_GPRS.length;
Offset off = Offset.fromIntSignExtend(numNonVols * WORDSIZE);
for (int i = 0; i < numNonVols; i++) {
asm.emitPUSH_Reg(NONVOLATILE_GPRS[i]);
}
// (3) Push args to C function (reversed)
asm.emitPUSH_RegDisp(SP, off.plus(4));
asm.emitPUSH_RegDisp(SP, off.plus(4));
asm.emitPUSH_RegDisp(SP, off.plus(20));
asm.emitPUSH_RegDisp(SP, off.plus(20));
// (4) invoke C function through bootrecord
asm.emitMOV_Reg_Abs(S0, Magic.getTocPointer().plus(Entrypoints.the_boot_recordField.getOffset()));
asm.emitCALL_RegDisp(S0, Entrypoints.sysLongRemainderIPField.getOffset());
// (5) pop space for arguments
adjustStack(4 * WORDSIZE, true);
// (6) restore RVM nonvolatiles
for (int i = numNonVols - 1; i >= 0; i--) {
asm.emitPOP_Reg(NONVOLATILE_GPRS[i]);
}
// (7) pop expression stack
adjustStack(WORDSIZE*4, true);
// (8) push results
asm.emitPUSH_Reg(T1);
asm.emitPUSH_Reg(T0);
genParameterRegisterLoad(asm, 4); // pass 4 parameter words
asm.emitCALL_Abs(Magic.getTocPointer().plus(Entrypoints.lremMethod.getOffset()));
asm.emitPUSH_Reg(T0); // high half
asm.emitPUSH_Reg(T1); // low half
}
}

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44 changes: 44 additions & 0 deletions rvm/src/org/jikesrvm/compilers/baseline/ia32/BaselineMagic.java
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Expand Up @@ -2058,6 +2058,50 @@ void generateMagic(Assembler asm, MethodReference m, RVMMethod cm, Offset sd) {
generators.put(getMethodReference(Magic.class, MagicNames.pause, void.class), g);
}

/**
* Signed long divide by 32bit divisor giving 32bit quotient
*/
private static final class SignedDivide extends MagicGenerator {
@Override
void generateMagic(Assembler asm, MethodReference m, RVMMethod cm, Offset sd) {
// stack: value1.high = divident
// value1.low
// value2 = divisor <-- ESP
if (VM.VerifyAssertions) VM._assert(S0 != EAX && S0 != EDX);
asm.emitPOP_Reg(S0);
asm.emitPOP_Reg(EAX);
asm.emitPOP_Reg(EDX);
asm.emitIDIV_Reg_Reg(EAX, S0);
asm.emitPUSH_Reg(EAX);
}
}
static {
MagicGenerator g = new SignedDivide();
generators.put(getMethodReference(Magic.class, MagicNames.signedDivide, long.class, int.class, int.class), g);
}

/**
* Unsigned long divide by 32bit divisor giving 32bit quotient
*/
private static final class UnsignedDivide extends MagicGenerator {
@Override
void generateMagic(Assembler asm, MethodReference m, RVMMethod cm, Offset sd) {
// stack: value1.high = divident
// value1.low
// value2 = divisor <-- ESP
if (VM.VerifyAssertions) VM._assert(S0 != EAX && S0 != EDX);
asm.emitPOP_Reg(S0);
asm.emitPOP_Reg(EAX);
asm.emitPOP_Reg(EDX);
asm.emitDIV_Reg_Reg(EAX, S0);
asm.emitPUSH_Reg(EAX);
}
}
static {
MagicGenerator g = new UnsignedDivide();
generators.put(getMethodReference(Magic.class, MagicNames.unsignedDivide, long.class, int.class, int.class), g);
}

/**
* Floating point square root
*/
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32 changes: 32 additions & 0 deletions rvm/src/org/jikesrvm/compilers/opt/hir2lir/ExpandRuntimeServices.java
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Expand Up @@ -18,6 +18,8 @@
import static org.jikesrvm.compilers.opt.ir.Operators.GETFIELD_opcode;
import static org.jikesrvm.compilers.opt.ir.Operators.GETSTATIC_opcode;
import static org.jikesrvm.compilers.opt.ir.Operators.INT_ASTORE;
import static org.jikesrvm.compilers.opt.ir.Operators.LONG_DIV_opcode;
import static org.jikesrvm.compilers.opt.ir.Operators.LONG_REM_opcode;
import static org.jikesrvm.compilers.opt.ir.Operators.MONITORENTER_opcode;
import static org.jikesrvm.compilers.opt.ir.Operators.MONITOREXIT_opcode;
import static org.jikesrvm.compilers.opt.ir.Operators.NEWARRAY_UNRESOLVED_opcode;
Expand Down Expand Up @@ -54,6 +56,7 @@
import org.jikesrvm.compilers.opt.ir.Call;
import org.jikesrvm.compilers.opt.ir.GetField;
import org.jikesrvm.compilers.opt.ir.GetStatic;
import org.jikesrvm.compilers.opt.ir.GuardedBinary;
import org.jikesrvm.compilers.opt.ir.IR;
import org.jikesrvm.compilers.opt.ir.IRTools;
import org.jikesrvm.compilers.opt.ir.Instruction;
Expand Down Expand Up @@ -138,6 +141,35 @@ public void perform(IR ir) {
int opcode = inst.getOpcode();

switch (opcode) {
case LONG_DIV_opcode: {
if (VM.BuildFor64Addr) break; // don't reduce operator
RVMMethod target = Entrypoints.ldivMethod;
Call.mutate2(inst,
CALL,
GuardedBinary.getClearResult(inst),
IRTools.AC(target.getOffset()),
MethodOperand.STATIC(target),
GuardedBinary.getClearVal1(inst),
GuardedBinary.getClearVal2(inst));
if (!ir.options.FREQ_FOCUS_EFFORT || !inst.getBasicBlock().getInfrequent()) {
inline(inst, ir);
}
}

case LONG_REM_opcode: {
if (VM.BuildFor64Addr) break; // don't reduce operator
RVMMethod target = Entrypoints.lremMethod;
Call.mutate2(inst,
CALL,
GuardedBinary.getClearResult(inst),
IRTools.AC(target.getOffset()),
MethodOperand.STATIC(target),
GuardedBinary.getClearVal1(inst),
GuardedBinary.getClearVal2(inst));
if (!ir.options.FREQ_FOCUS_EFFORT || !inst.getBasicBlock().getInfrequent()) {
inline(inst, ir);
}
}

case NEW_opcode: {
TypeOperand Type = New.getClearType(inst);
Expand Down
28 changes: 0 additions & 28 deletions rvm/src/org/jikesrvm/compilers/opt/lir2mir/ConvertLIRtoMIR.java
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Expand Up @@ -216,34 +216,6 @@ public void perform(IR ir) {
}
break;

case LONG_DIV_opcode: {
if (VM.BuildForPowerPC && VM.BuildFor64Addr) break; // don't reduce operator -- leave for BURS
Call.mutate2(s,
SYSCALL,
GuardedBinary.getClearResult(s),
null,
MethodOperand.STATIC(Entrypoints.sysLongDivideIPField),
GuardedBinary.getClearVal1(s),
GuardedBinary.getClearVal2(s));
ConvertToLowLevelIR.expandSysCallTarget(s, ir);
CallingConvention.expandSysCall(s, ir);
}
break;

case LONG_REM_opcode: {
if (VM.BuildForPowerPC && VM.BuildFor64Addr) break; // don't reduce operator -- leave for BURS
Call.mutate2(s,
SYSCALL,
GuardedBinary.getClearResult(s),
null,
MethodOperand.STATIC(Entrypoints.sysLongRemainderIPField),
GuardedBinary.getClearVal1(s),
GuardedBinary.getClearVal2(s));
ConvertToLowLevelIR.expandSysCallTarget(s, ir);
CallingConvention.expandSysCall(s, ir);
}
break;

case FLOAT_REM_opcode:
case DOUBLE_REM_opcode: {
if (VM.BuildForPowerPC) {
Expand Down
4 changes: 0 additions & 4 deletions rvm/src/org/jikesrvm/runtime/BootRecord.java
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Original file line number Diff line number Diff line change
Expand Up @@ -266,10 +266,6 @@ public void setHeapRange(int id, Address start, Address end) {

// arithmetic
@Entrypoint
public Address sysLongDivideIP;
@Entrypoint
public Address sysLongRemainderIP;
@Entrypoint
public Address sysLongToFloatIP;
@Entrypoint
public Address sysLongToDoubleIP;
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9 changes: 5 additions & 4 deletions rvm/src/org/jikesrvm/runtime/Entrypoints.java
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Original file line number Diff line number Diff line change
Expand Up @@ -45,6 +45,11 @@ public class Entrypoints {
"objectAddressRemapper",
org.jikesrvm.runtime.ObjectAddressRemapper.class);

public static final NormalMethod ldivMethod =
getMethod(org.jikesrvm.runtime.RuntimeEntrypoints.class, "ldiv", "(JJ)J");
public static final NormalMethod lremMethod =
getMethod(org.jikesrvm.runtime.RuntimeEntrypoints.class, "lrem", "(JJ)J");

public static final NormalMethod instanceOfMethod =
getMethod(org.jikesrvm.runtime.RuntimeEntrypoints.class, "instanceOf", "(Ljava/lang/Object;I)Z");
public static final NormalMethod checkcastMethod =
Expand Down Expand Up @@ -331,10 +336,6 @@ public class Entrypoints {
getField(org.jikesrvm.runtime.BootRecord.class, "the_boot_record", org.jikesrvm.runtime.BootRecord.class);
public static final RVMField externalSignalFlagField =
getField(org.jikesrvm.runtime.BootRecord.class, "externalSignalFlag", int.class);
public static final RVMField sysLongDivideIPField =
getField(org.jikesrvm.runtime.BootRecord.class, "sysLongDivideIP", org.vmmagic.unboxed.Address.class);
public static final RVMField sysLongRemainderIPField =
getField(org.jikesrvm.runtime.BootRecord.class, "sysLongRemainderIP", org.vmmagic.unboxed.Address.class);
public static final RVMField sysLongToFloatIPField =
getField(org.jikesrvm.runtime.BootRecord.class, "sysLongToFloatIP", org.vmmagic.unboxed.Address.class);
public static final RVMField sysLongToDoubleIPField =
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20 changes: 20 additions & 0 deletions rvm/src/org/jikesrvm/runtime/Magic.java
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Original file line number Diff line number Diff line change
Expand Up @@ -877,6 +877,26 @@ public static void pause() {
}
}

/**
* A hardware signed long divide by 32bit divisor giving 32bit quotient
*/
public static int signedDivide(long u, int v) {
if (VM.runningVM && VM.VerifyAssertions) {
VM._assert(VM.NOT_REACHED); // call site should have been hijacked by magic in compiler
}
return 0;
}

/**
* A hardware unsigned long divide by 32bit divisor giving 32bit quotient
*/
public static int unsignedDivide(long u, int v) {
if (VM.runningVM && VM.VerifyAssertions) {
VM._assert(VM.NOT_REACHED); // call site should have been hijacked by magic in compiler
}
return 0;
}

/**
* A hardware SQRT instruction
*/
Expand Down
2 changes: 2 additions & 0 deletions rvm/src/org/jikesrvm/runtime/MagicNames.java
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Original file line number Diff line number Diff line change
Expand Up @@ -62,6 +62,8 @@ public class MagicNames {
public static final Atom loadObjectReference = Atom.findOrCreateAsciiAtom("loadObjectReference");
public static final Atom store = Atom.findOrCreateAsciiAtom("store");
public static final Atom pause = Atom.findOrCreateAsciiAtom("pause");
public static final Atom signedDivide = Atom.findOrCreateAsciiAtom("signedDivide");
public static final Atom unsignedDivide = Atom.findOrCreateAsciiAtom("unsignedDivide");
public static final Atom sqrt = Atom.findOrCreateAsciiAtom("sqrt");

public static final Atom getUnsignedByteAtOffset = Atom.findOrCreateAsciiAtom("getUnsignedByteAtOffset");
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74 changes: 74 additions & 0 deletions rvm/src/org/jikesrvm/runtime/RuntimeEntrypoints.java
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Original file line number Diff line number Diff line change
Expand Up @@ -92,6 +92,80 @@ public class RuntimeEntrypoints implements Constants, ArchitectureSpecific.Stack
public static final int TRAP_STORE_CHECK = 8; // opt-compiler
public static final int TRAP_STACK_OVERFLOW_FATAL = 9; // assertion checking

/**
* Perform signed division implementing the ldiv bytecode
*
* @param u dividend
* @param v divisor
* @return quotient
*/
@Entrypoint
static long ldiv(long u, long v) {
if (v == 0) {
raiseArithmeticException();
}
long au = Math.abs(u);
long av = Math.abs(v);
if ((av >>> 31) == 0) {
if (au < (av << 31)) {
long q = Magic.signedDivide(u, (int)v);
return (q << 32) >> 32;
}
}
long q = unsignedDivide(au, av);
long t = (u ^ v) >> 63;
return (q ^ t) - t;
}

/**
* Perform the unsigned division subcase of the ldiv bytecode
*
* @param u dividend
* @param v divisor
* @return quotient
*/
private static long unsignedDivide(long u, long v) {
if ((v >>> 32) == 0) {
if ((u >>> 32) < v) {
return Magic.unsignedDivide(u, (int)v) & 0xFFFFFFFF;
} else {
long u1 = u >>> 32;
long u0 = u & 0xFFFFFFFF;
long q1 = Magic.unsignedDivide(u1, (int)v) & 0xFFFFFFFF;
long k = u1 - q1 * v;
long q0 = Magic.unsignedDivide((k << 32) + u0, (int)v) & 0xFFFFFFFF;
return (q1 << 32) + q0;
}
} else {
int n = Long.numberOfLeadingZeros(v);
long v1 = (v << n) >>> 32;
long u1 = u >>> 1;
long q1 = Magic.unsignedDivide(u1, (int)v1) & 0xFFFFFFFF;
long q0 = (q1 << n) >>> 31;
if (q0 != 0) {
q0 = q0-1;
}
if ((u - q0*v) >= v) {
q0 = q0+1;
}
return q0;
}
}

/**
* Perform signed remainder implementing the lrem bytecode
*
* @param u dividend
* @param v divisor
* @return remainder
*/
@Entrypoint
static long lrem(long u, long v) {
// @TODO: optimize this further
long r = ldiv(u, v);
return u - (r * v);
}

//---------------------------------------------------------------//
// Type Checking. //
//---------------------------------------------------------------//
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6 changes: 0 additions & 6 deletions rvm/src/org/jikesrvm/runtime/SysCall.java
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Original file line number Diff line number Diff line change
Expand Up @@ -214,12 +214,6 @@ public abstract class SysCall {
public abstract void sysMonitorNotifyAll(Address monitor);

// arithmetic
@SysCallTemplate
public abstract long sysLongDivide(long x, long y);

@SysCallTemplate
public abstract long sysLongRemainder(long x, long y);

@SysCallTemplate
public abstract float sysLongToFloat(long x);

Expand Down

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