public void detectedCountedLoops() {
for (LoopEx loop : loops()) {
InductionVariables ivs = new InductionVariables(loop);
LoopBeginNode loopBegin = loop.loopBegin();
FixedNode next = loopBegin.next();
while (next instanceof FixedGuardNode || next instanceof ValueAnchorNode) {
next = ((FixedWithNextNode) next).next();
}
if (next instanceof IfNode) {
IfNode ifNode = (IfNode) next;
boolean negated = false;
if (!loopBegin.isLoopExit(ifNode.falseSuccessor())) {
if (!loopBegin.isLoopExit(ifNode.trueSuccessor())) {
continue;
}
negated = true;
}
LogicNode ifTest = ifNode.condition();
if (!(ifTest instanceof IntegerLessThanNode)) {
if (ifTest instanceof IntegerBelowThanNode) {
Debug.log("Ignored potential Counted loop at %s with |<|", loopBegin);
}
continue;
}
IntegerLessThanNode lessThan = (IntegerLessThanNode) ifTest;
Condition condition = null;
InductionVariable iv = null;
ValueNode limit = null;
if (loop.isOutsideLoop(lessThan.x())) {
iv = ivs.get(lessThan.y());
if (iv != null) {
condition = lessThan.condition().mirror();
limit = lessThan.x();
}
} else if (loop.isOutsideLoop(lessThan.y())) {
iv = ivs.get(lessThan.x());
if (iv != null) {
condition = lessThan.condition();
limit = lessThan.y();
}
}
if (condition == null) {
continue;
}
if (negated) {
condition = condition.negate();
}
boolean oneOff = false;
switch (condition) {
case LE:
oneOff = true; // fall through
case LT:
if (iv.direction() != Direction.Up) {
continue;
}
break;
case GE:
oneOff = true; // fall through
case GT:
if (iv.direction() != Direction.Down) {
continue;
}
break;
default:
throw GraalInternalError.shouldNotReachHere();
}
loop.setCounted(
new CountedLoopInfo(
loop,
iv,
limit,
oneOff,
negated ? ifNode.falseSuccessor() : ifNode.trueSuccessor()));
}
}
}
public static void emit(
TargetMethodAssembler tasm, AMD64MacroAssembler masm, AMD64Compare opcode, Value x, Value y) {
if (isRegister(y)) {
switch (opcode) {
case ICMP:
masm.cmpl(asIntReg(x), asIntReg(y));
break;
case LCMP:
masm.cmpq(asLongReg(x), asLongReg(y));
break;
case ACMP:
masm.cmpptr(asObjectReg(x), asObjectReg(y));
break;
case FCMP:
masm.ucomiss(asFloatReg(x), asFloatReg(y));
break;
case DCMP:
masm.ucomisd(asDoubleReg(x), asDoubleReg(y));
break;
default:
throw GraalInternalError.shouldNotReachHere();
}
} else if (isConstant(y)) {
switch (opcode) {
case ICMP:
masm.cmpl(asIntReg(x), tasm.asIntConst(y));
break;
case LCMP:
masm.cmpq(asLongReg(x), tasm.asIntConst(y));
break;
case ACMP:
if (((Constant) y).isNull()) {
masm.cmpq(asObjectReg(x), 0);
break;
} else {
throw GraalInternalError.shouldNotReachHere(
"Only null object constants are allowed in comparisons");
}
case FCMP:
masm.ucomiss(asFloatReg(x), (AMD64Address) tasm.asFloatConstRef(y));
break;
case DCMP:
masm.ucomisd(asDoubleReg(x), (AMD64Address) tasm.asDoubleConstRef(y));
break;
default:
throw GraalInternalError.shouldNotReachHere();
}
} else {
switch (opcode) {
case ICMP:
masm.cmpl(asIntReg(x), (AMD64Address) tasm.asIntAddr(y));
break;
case LCMP:
masm.cmpq(asLongReg(x), (AMD64Address) tasm.asLongAddr(y));
break;
case ACMP:
masm.cmpptr(asObjectReg(x), (AMD64Address) tasm.asObjectAddr(y));
break;
case FCMP:
masm.ucomiss(asFloatReg(x), (AMD64Address) tasm.asFloatAddr(y));
break;
case DCMP:
masm.ucomisd(asDoubleReg(x), (AMD64Address) tasm.asDoubleAddr(y));
break;
default:
throw GraalInternalError.shouldNotReachHere();
}
}
}