X-Git-Url: https://mograsim.net/gitweb/?a=blobdiff_plain;f=era.mi%2Fsrc%2Fera%2Fmi%2Flogic%2Fwires%2FWireArray.java;h=957f00b196dce3dd9e2d321a8deb8aad7b899546;hb=74aebd92f41d03f4a44c9a455ef8c05465136412;hp=cf960e084c3cb3b78fccf15fd6abcd5f22a41cea;hpb=ebe86d1517aea138ffb6485b7bd2dff31fdb1253;p=Mograsim.git diff --git a/era.mi/src/era/mi/logic/wires/WireArray.java b/era.mi/src/era/mi/logic/wires/WireArray.java index cf960e08..957f00b1 100644 --- a/era.mi/src/era/mi/logic/wires/WireArray.java +++ b/era.mi/src/era/mi/logic/wires/WireArray.java @@ -7,77 +7,69 @@ import java.util.List; import era.mi.logic.Bit; import era.mi.logic.Simulation; +import era.mi.logic.Util; /** * Represents an array of wires that can store n bits of information. + * * @author Fabian Stemmler * */ -public class WireArray -{ +public class WireArray { private Bit[] values; public final int travelTime; private List observers = new ArrayList(); public final int length; private List inputs = new ArrayList(); - - public WireArray(int length, int travelTime) - { - if(length < 1) - throw new IllegalArgumentException("Tried to create an array of wires with length " + length + ", but a length of less than 1 makes no sense."); + + public WireArray(int length, int travelTime) { + if (length < 1) + throw new IllegalArgumentException( + String.format("Tried to create an array of wires with length %d, but a length of less than 1 makes no sense.", length)); this.length = length; this.travelTime = travelTime; initValues(); } - - private void initValues() - { - values = new Bit[length]; - for(int i = 0; i < length; i++) - values[i] = Bit.Z; + + private void initValues() { + values = Bit.Z.makeArray(length); } - - private void recalculateSingleInput() - { + + private void recalculateSingleInput() { WireArrayInput input = inputs.get(0); - if(!Arrays.equals(input.getValues(), values)) - { + if (!Arrays.equals(input.getValues(), values)) { + Bit[] oldValues = values.clone(); System.arraycopy(input.getValues(), 0, values, 0, length); - notifyObservers(); + notifyObservers(oldValues); } } - - private void recalculateMultipleInputs() - { + + private void recalculateMultipleInputs() { Iterator it = inputs.iterator(); - Bit[] newValues = it.next().values.clone(); - - while(it.hasNext()) - { + Bit[] newValues = it.next().inputValues.clone(); + + while (it.hasNext()) { WireArrayInput input = it.next(); Bit[] bits = input.getValues(); - for(int i = 0; i < length; i++) - { - if(Bit.Z.equals(bits[i]) || newValues[i].equals(bits[i])) + for (int i = 0; i < length; i++) { + if (Bit.Z.equals(bits[i]) || newValues[i].equals(bits[i])) continue; - else if(Bit.Z.equals(newValues[i])) + else if (Bit.Z.equals(newValues[i])) newValues[i] = bits[i]; else newValues[i] = Bit.X; } } - - if(!Arrays.equals(newValues, values)) - { - notifyObservers(); + + if (!Arrays.equals(newValues, values)) { + Bit[] oldValues = values; values = newValues; + notifyObservers(oldValues); } } - private void recalculate() - { - switch(inputs.size()) - { + private void recalculate() { + switch (inputs.size()) { case 0: return; case 1: @@ -87,41 +79,40 @@ public class WireArray recalculateMultipleInputs(); } } - + /** * The WireArray is interpreted as an unsigned integer with n bits. - * @return true if all bits are either Bit.ONE or Bit.ZERO (they do not all have to have the same value), not Bit.X or Bit.Z. false is returned otherwise. + * + * @return true if all bits are either Bit.ONE or Bit.ZERO (they do not all have to have the same + * value), not Bit.X or Bit.Z. false is returned otherwise. * * @author Fabian Stemmler */ - public boolean hasNumericValue() - { - for(Bit b : values) - { - if(b != Bit.ZERO && b != Bit.ONE) + public boolean hasNumericValue() { + for (Bit b : values) { + if (b != Bit.ZERO && b != Bit.ONE) return false; } return true; } - + /** * The WireArray is interpreted as an unsigned integer with n bits. + * * @return The unsigned value of the {@link WireArray}'s bits, where value 0 corresponds with 2^0, value 1 is 2^1 and so on. * * @author Fabian Stemmler */ - public long getUnsignedValue() - { + public long getUnsignedValue() { long val = 0; long mask = 1; - for(int i = 0; i < length; i++) - { - switch(values[i]) - { + for (int i = 0; i < length; i++) { + switch (values[i]) { default: case Z: case X: - return 0; //TODO: Proper handling for getUnsignedValue(), if not all bits are 1 or 0; Random number? + return 0; // TODO: Proper handling for getUnsignedValue(), if not all bits are 1 or 0; + // Random number? case ONE: val |= mask; break; @@ -131,36 +122,35 @@ public class WireArray } return val; } - + /** * The WireArray is interpreted as a signed integer with n bits. + * * @return The signed value of the {@link WireArray}'s bits, where value 0 corresponds with 2^0, value 1 is 2^1 and so on. * * @author Fabian Stemmler */ - public long getSignedValue() - { + public long getSignedValue() { long val = getUnsignedValue(); long mask = 1 << (length - 1); - if((mask & val) != 0) - { + if ((mask & val) != 0) { int shifts = 64 - length; return (val << shifts) >> shifts; } return val; } - + /** * Included for convenient use on {@link WireArray}s of length 1. + * * @return The value of bit 0. * * @author Fabian Stemmler */ - public Bit getValue() - { + public Bit getValue() { return getValue(0); } - + /** * * @param index Index of the requested bit. @@ -168,128 +158,155 @@ public class WireArray * * @author Fabian Stemmler */ - public Bit getValue(int index) - { + public Bit getValue(int index) { return values[index]; } - - public Bit[] getValues(int start, int end) - { + + public Bit[] getValues(int start, int end) { int length = end - start; Bit[] bits = new Bit[length]; - System.arraycopy(values, start, bits, 0, length); + System.arraycopy(values, start, bits, 0, length); return bits; } - - + /** * @return An array of length n containing the values of the n bits in the {@link WireArray}. Can be safely modified. * * @author Fabian Stemmler */ - public Bit[] getValues() - { + public Bit[] getValues() { return values.clone(); } - + /** * Adds an {@link WireArrayObserver}, who will be notified when the value of the {@link WireArray} is updated. + * * @param ob The {@link WireArrayObserver} to be notified of changes. * @return true if the given {@link WireArrayObserver} was not already registered, false otherwise * * @author Fabian Stemmler */ - public boolean addObserver(WireArrayObserver ob) - { + public boolean addObserver(WireArrayObserver ob) { return observers.add(ob); } - - private void notifyObservers() - { - for(WireArrayObserver o : observers) - o.update(this); + + private void notifyObservers(Bit[] oldValues) { + for (WireArrayObserver o : observers) + o.update(this, oldValues); } - - public WireArrayInput createInput() - { + + /** + * Create and register a {@link WireArrayInput} object, which is tied to this {@link WireArray}. + */ + public WireArrayInput createInput() { return new WireArrayInput(this); } - - private void registerInput(WireArrayInput toRegister) - { + + private void registerInput(WireArrayInput toRegister) { inputs.add(toRegister); } - + + /** + * A {@link WireArrayInput} feeds a constant signal into the {@link WireArray} it is tied to. The combination of all inputs determines + * the {@link WireArray}s final value. X dominates all other inputs Z does not affect the final value, unless there are no other inputs + * than Z 0 and 1 turn into X when they are mixed + * + * @author Fabian Stemmler + */ public class WireArrayInput { public final WireArray owner; - private Bit[] values; - + private Bit[] inputValues; + private WireArrayInput(WireArray owner) { super(); this.owner = owner; initValues(); owner.registerInput(this); } - - private void initValues() - { - values = new Bit[length]; - for(int i = 0; i < length; i++) - values[i] = Bit.Z; + + private void initValues() { + inputValues = Bit.Z.makeArray(length); } - + /** * Sets the wires values. This takes up time, as specified by the {@link WireArray}s travel time. + * * @param newValues The new values the wires should take on. * * @author Fabian Stemmler */ - public void feedSignals(Bit... newValues) - { - if(newValues.length == length) - { + public void feedSignals(Bit... newValues) { + if (newValues.length == length) { feedSignals(0, newValues); - } - else - throw new IllegalArgumentException("Attempted to input " + newValues.length + " bits instead of " + length + " bits."); + } else + throw new IllegalArgumentException( + String.format("Attempted to input %o bits instead of %o bits.", newValues.length, length)); } - + /** * Sets values of a subarray of wires. This takes up time, as specified by the {@link WireArray}s travel time. - * @param newValues The new values the wires should take on. + * + * @param newValues The new values the wires should take on. * @param startingBit The first index of the subarray of wires. * * @author Fabian Stemmler */ - public void feedSignals(int startingBit, Bit... newValues) - { + public void feedSignals(int startingBit, Bit... newValues) { Simulation.TIMELINE.addEvent((e) -> setValues(startingBit, newValues), travelTime); } - - private void setValues(int startingBit, Bit... newValues) - { + + private void setValues(int startingBit, Bit... newValues) { int exclLastIndex = startingBit + newValues.length; - if(length < exclLastIndex) - throw new ArrayIndexOutOfBoundsException("Attempted to input bits from index " + startingBit + " to " - + exclLastIndex + " when there are only " + length + "wires."); - if(!Arrays.equals(values, startingBit, exclLastIndex, newValues, 0, newValues.length)) - { - System.arraycopy(newValues, 0, values, startingBit, newValues.length); + if (length < exclLastIndex) + throw new ArrayIndexOutOfBoundsException( + String.format("Attempted to input bits from index %o to %o when there are only %o wires.", startingBit, + exclLastIndex - 1, length)); + if (!Arrays.equals(inputValues, startingBit, exclLastIndex, newValues, 0, newValues.length)) { + System.arraycopy(newValues, 0, inputValues, startingBit, newValues.length); owner.recalculate(); } } - - public Bit[] getValues() - { - return values.clone(); + + /** + * Returns a copy (safe to modify) of the values the {@link WireArrayInput} is currently feeding into the associated + * {@link WireArray}. + */ + public Bit[] getValues() { + return inputValues.clone(); } - - public void clearSignals() - { - Bit[] bits = new Bit[length]; - for(int i = 0; i < length; i++) - bits[i] = Bit.Z; - feedSignals(bits); + + /** + * {@link WireArrayInput} now feeds Z into the associated {@link WireArray}. + */ + public void clearSignals() { + feedSignals(Bit.Z.makeArray(length)); + } + + public Bit[] wireValuesExcludingMe() { + Bit[] bits = Bit.Z.makeArray(length); + for (WireArrayInput wai : inputs) { + if (wai == this) + continue; + Util.combineInto(bits, wai.getValues()); + } + return bits; } + + @Override + public String toString() { + return Arrays.toString(inputValues); + } + } + + @Override + public String toString() { + return String.format("wire 0x%08x value: %s inputs: %s", hashCode(), Arrays.toString(values), inputs); + } + + public static WireArrayInput[] extractInputs(WireArray[] w) { + WireArrayInput[] inputs = new WireArrayInput[w.length]; + for (int i = 0; i < w.length; i++) + inputs[i] = w[i].createInput(); + return inputs; } -} +} \ No newline at end of file