JumpFlash.java

package com.rox.debug.cpu;

import com.rox.cpu.mos6502.assembler.DisassembledInstruction;

import java.util.List;
import java.util.function.LongSupplier;

/**
 * Whether to flash the current instruction's address: for {@link #FLASH_MILLIS} after a step lands on it by a
 * jump - any way control moves other than to the next instruction (JMP, JSR, RTS/RTI, a taken branch, an
 * interrupt) - while it's still the current instruction. Only while paused: running, nearly every refresh
 * follows some jump, so it would never stop.
 */
public final class JumpFlash {
    static final long FLASH_MILLIS = 600;
    private static final int ADDRESS_MASK = 0xFFFF;

    private final LongSupplier clockMillis;
    private long lastInstructionCount;
    private boolean pausedLastTime;
    private long flashUntil = Long.MIN_VALUE;

    /** @param clockMillis e.g. {@code System::currentTimeMillis} */
    public JumpFlash(final LongSupplier clockMillis){
        this.clockMillis = clockMillis;
    }

    /**
     * @param instructionCount see {@link CpuDebugSource#instructionCount()} - a rise while paused is a step
     * @param recent recently executed instructions, oldest first - see {@link CpuDebugSource#recentInstructions()}
     * @param currentAddress where the current instruction starts
     * @return whether the address should be flashing now
     */
    public boolean update(final long instructionCount, final boolean paused, final List<DisassembledInstruction> recent,
                          final int currentAddress){
        final long now = clockMillis.getAsLong();
        if (!paused){
            flashUntil = Long.MIN_VALUE;
            pausedLastTime = false;
            lastInstructionCount = instructionCount;
            return false;
        }
        //an instruction run while already paused is a step; the first look after pausing is not
        if (pausedLastTime && instructionCount != lastInstructionCount){
            //a step that didn't jump ends any flash still showing for the instruction before it
            flashUntil = landedByJump(recent, currentAddress) ? now + FLASH_MILLIS : Long.MIN_VALUE;
        }
        pausedLastTime = true;
        lastInstructionCount = instructionCount;
        return now < flashUntil;
    }

    /** True unless {@code currentAddress} directly follows the last executed instruction. */
    static boolean landedByJump(final List<DisassembledInstruction> recent, final int currentAddress){
        if (recent.isEmpty()){
            return false;
        }
        final DisassembledInstruction previous = recent.get(recent.size() - 1);
        return ((previous.address() + previous.length()) & ADDRESS_MASK) != currentAddress;
    }
}











Active mutators

CONDITIONALS_BOUNDARY
EMPTY_RETURNS
FALSE_RETURNS
INCREMENTS
INVERT_NEGS
MATH
NEGATE_CONDITIONALS
NULL_RETURNS
PRIMITIVE_RETURNS
TRUE_RETURNS
VOID_METHOD_CALLS

Tests examined

com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:anUnchangedRefreshDoesNotRetriggerTheFlash()] (0 ms)
com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:pausingIsNotAStep()] (0 ms)
com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:landedByJumpIsFalseWithNoHistoryOrASequentialStepAndHandlesWrapAround()] (0 ms)
com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:aStepThatJumpedFlashesForAWhileThenStops()] (0 ms)
com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:aStepToTheNextInstructionDoesNotFlash()] (0 ms)
com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:resumingEndsTheFlash()] (0 ms)
com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:aSequentialStepEndsAFlashStillShowingForTheInstructionBefore()] (0 ms)
com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:everyStepOfAJumpToItselfFlashes()] (2 ms)
com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:runningNeverFlashes()] (0 ms)
com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:theFirstLookNeverFlashes()] (0 ms)

Report generated by PIT 1.22.1

1		package com.rox.debug.cpu;
2
3		import com.rox.cpu.mos6502.assembler.DisassembledInstruction;
4
5		import java.util.List;
6		import java.util.function.LongSupplier;
7
8		/**
9		* Whether to flash the current instruction's address: for {@link #FLASH_MILLIS} after a step lands on it by a
10		* jump - any way control moves other than to the next instruction (JMP, JSR, RTS/RTI, a taken branch, an
11		* interrupt) - while it's still the current instruction. Only while paused: running, nearly every refresh
12		* follows some jump, so it would never stop.
13		*/
14		public final class JumpFlash {
15		static final long FLASH_MILLIS = 600;
16		private static final int ADDRESS_MASK = 0xFFFF;
17
18		private final LongSupplier clockMillis;
19		private long lastInstructionCount;
20		private boolean pausedLastTime;
21		private long flashUntil = Long.MIN_VALUE;
22
23		/** @param clockMillis e.g. {@code System::currentTimeMillis} */
24		public JumpFlash(final LongSupplier clockMillis){
25		this.clockMillis = clockMillis;
26		}
27
28		/**
29		* @param instructionCount see {@link CpuDebugSource#instructionCount()} - a rise while paused is a step
30		* @param recent recently executed instructions, oldest first - see {@link CpuDebugSource#recentInstructions()}
31		* @param currentAddress where the current instruction starts
32		* @return whether the address should be flashing now
33		*/
34		public boolean update(final long instructionCount, final boolean paused, final List<DisassembledInstruction> recent,
35		final int currentAddress){
36		final long now = clockMillis.getAsLong();
37	1 1. update : negated conditional → KILLED	if (!paused){
38		flashUntil = Long.MIN_VALUE;
39		pausedLastTime = false;
40		lastInstructionCount = instructionCount;
41	1 1. update : replaced boolean return with true for com/rox/debug/cpu/JumpFlash::update → KILLED	return false;
42		}
43		//an instruction run while already paused is a step; the first look after pausing is not
44	2 1. update : negated conditional → KILLED 2. update : negated conditional → KILLED	if (pausedLastTime && instructionCount != lastInstructionCount){
45		//a step that didn't jump ends any flash still showing for the instruction before it
46	2 1. update : Replaced long addition with subtraction → KILLED 2. update : negated conditional → KILLED	flashUntil = landedByJump(recent, currentAddress) ? now + FLASH_MILLIS : Long.MIN_VALUE;
47		}
48		pausedLastTime = true;
49		lastInstructionCount = instructionCount;
50	3 1. update : negated conditional → KILLED 2. update : changed conditional boundary → KILLED 3. update : replaced boolean return with true for com/rox/debug/cpu/JumpFlash::update → KILLED	return now < flashUntil;
51		}
52
53		/** True unless {@code currentAddress} directly follows the last executed instruction. */
54		static boolean landedByJump(final List<DisassembledInstruction> recent, final int currentAddress){
55	1 1. landedByJump : negated conditional → KILLED	if (recent.isEmpty()){
56	1 1. landedByJump : replaced boolean return with true for com/rox/debug/cpu/JumpFlash::landedByJump → KILLED	return false;
57		}
58	1 1. landedByJump : Replaced integer subtraction with addition → KILLED	final DisassembledInstruction previous = recent.get(recent.size() - 1);
59	4 1. landedByJump : Replaced integer addition with subtraction → KILLED 2. landedByJump : Replaced bitwise AND with OR → KILLED 3. landedByJump : negated conditional → KILLED 4. landedByJump : replaced boolean return with true for com/rox/debug/cpu/JumpFlash::landedByJump → KILLED	return ((previous.address() + previous.length()) & ADDRESS_MASK) != currentAddress;
60		}
61		}
		Mutations
37		1.1 Location : update Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:runningNeverFlashes()] negated conditional → KILLED
41		1.1 Location : update Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:runningNeverFlashes()] replaced boolean return with true for com/rox/debug/cpu/JumpFlash::update → KILLED
44		1.1 Location : update Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:anUnchangedRefreshDoesNotRetriggerTheFlash()] negated conditional → KILLED 2.2 Location : update Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:theFirstLookNeverFlashes()] negated conditional → KILLED
46		1.1 Location : update Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:pausingIsNotAStep()] Replaced long addition with subtraction → KILLED 2.2 Location : update Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:pausingIsNotAStep()] negated conditional → KILLED
50		1.1 Location : update Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:theFirstLookNeverFlashes()] negated conditional → KILLED 2.2 Location : update Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:anUnchangedRefreshDoesNotRetriggerTheFlash()] changed conditional boundary → KILLED 3.3 Location : update Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:theFirstLookNeverFlashes()] replaced boolean return with true for com/rox/debug/cpu/JumpFlash::update → KILLED
55		1.1 Location : landedByJump Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:pausingIsNotAStep()] negated conditional → KILLED
56		1.1 Location : landedByJump Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:landedByJumpIsFalseWithNoHistoryOrASequentialStepAndHandlesWrapAround()] replaced boolean return with true for com/rox/debug/cpu/JumpFlash::landedByJump → KILLED
58		1.1 Location : landedByJump Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:anUnchangedRefreshDoesNotRetriggerTheFlash()] Replaced integer subtraction with addition → KILLED
59		1.1 Location : landedByJump Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:landedByJumpIsFalseWithNoHistoryOrASequentialStepAndHandlesWrapAround()] Replaced integer addition with subtraction → KILLED 2.2 Location : landedByJump Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:landedByJumpIsFalseWithNoHistoryOrASequentialStepAndHandlesWrapAround()] Replaced bitwise AND with OR → KILLED 3.3 Location : landedByJump Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:pausingIsNotAStep()] negated conditional → KILLED 4.4 Location : landedByJump Killed by : com.rox.debug.cpu.JumpFlashTest.[engine:junit-jupiter]/[class:com.rox.debug.cpu.JumpFlashTest]/[method:landedByJumpIsFalseWithNoHistoryOrASequentialStepAndHandlesWrapAround()] replaced boolean return with true for com/rox/debug/cpu/JumpFlash::landedByJump → KILLED

JumpFlash.java

Mutations

Active mutators

Tests examined