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/*
* Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.oracle.truffle.api.debug;
import java.net.URI;
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import java.util.Objects;
import java.util.Set;
import java.util.concurrent.atomic.AtomicLong;
import com.oracle.truffle.api.Assumption;
import com.oracle.truffle.api.CallTarget;
import com.oracle.truffle.api.CompilerAsserts;
import com.oracle.truffle.api.CompilerDirectives;
import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
import com.oracle.truffle.api.Truffle;
import com.oracle.truffle.api.TruffleException;
import com.oracle.truffle.api.frame.MaterializedFrame;
import com.oracle.truffle.api.frame.VirtualFrame;
import com.oracle.truffle.api.instrumentation.EventBinding;
import com.oracle.truffle.api.instrumentation.EventContext;
import com.oracle.truffle.api.instrumentation.ExecuteSourceEvent;
import com.oracle.truffle.api.instrumentation.ExecuteSourceListener;
import com.oracle.truffle.api.instrumentation.ExecutionEventNode;
import com.oracle.truffle.api.instrumentation.ExecutionEventNodeFactory;
import com.oracle.truffle.api.instrumentation.SourceFilter;
import com.oracle.truffle.api.instrumentation.SourceSectionFilter;
import com.oracle.truffle.api.instrumentation.TruffleInstrument;
import com.oracle.truffle.api.nodes.DirectCallNode;
import com.oracle.truffle.api.nodes.ExecutableNode;
import com.oracle.truffle.api.nodes.ExplodeLoop;
import com.oracle.truffle.api.nodes.Node;
import com.oracle.truffle.api.nodes.RootNode;
import com.oracle.truffle.api.nodes.SlowPathException;
import com.oracle.truffle.api.profiles.BranchProfile;
import com.oracle.truffle.api.source.Source;
import com.oracle.truffle.api.source.SourceSection;
/**
* A request that guest language program execution be suspended at specified locations on behalf of
* a debugging client {@linkplain DebuggerSession session}.
*
*
Breakpoint lifetime
*
*
* - A client of a {@link DebuggerSession} uses a {@link Builder} to create a new breakpoint,
* choosing among multiple ways to specify the intended location. Examples include a specified
* {@link #newBuilder(Source) source}, a specified {@link #newBuilder(URI) URI}, line ranges, or an
* exact {@link #newBuilder(SourceSection) SourceSection}.
*
* - A new breakpoint cannot affect execution until after it has been
* {@linkplain DebuggerSession#install(Breakpoint) installed} by a session, which may be done only
* once.
*
* - A breakpoint that is both installed and {@linkplain Breakpoint#isEnabled() enabled} (true by
* default) will suspend any guest language execution thread that arrives at a matching AST
* location. The breakpoint (synchronously) {@linkplain SuspendedCallback calls back} to the
* responsible session on the execution thread.
*
* - A breakpoint may be enabled or disabled any number of times.
*
* - A breakpoint that is no longer needed may be {@linkplain #dispose() disposed}. A disposed
* breakpoint:
*
* - is disabled
* - is not installed in any session
* - can have no effect on program execution, and
* - must not be used again.
*
*
*
* - A session being {@linkplain DebuggerSession#close() closed} disposes all installed
* breakpoints.
*
*
*
* Example usage: {@link com.oracle.truffle.api.debug.BreakpointSnippets#example()}
*
* @since 0.9
*/
public class Breakpoint {
/**
* Specifies a breakpoint kind. Breakpoints with different kinds have different creation methods
* and address different debugging needs.
*
* @since 1.0
*/
public enum Kind {
/**
* Represents breakpoints submitted for a halt instruction in a guest language program. For
* instance, in JavaScript this is debugger statement. Guest languages mark
* such nodes with {@link DebuggerTags.AlwaysHalt}. A breakpoint of this kind is created by
* {@link DebuggerSession} automatically.
*
* @since 1.0
*/
HALT_INSTRUCTION,
/**
* Represents breakpoints submitted for a particular source code location. Use one of the
* newBuilder methods to create a breakpoint of this kind.
*
* @since 1.0
*/
SOURCE_LOCATION,
/**
* Represents exception breakpoints that are hit when an exception is thrown from a guest
* language program. Use {@link #newExceptionBuilder(boolean, boolean)} to create a
* breakpoint of this kind.
*
* @since 1.0
*/
EXCEPTION;
static final Kind[] VALUES = values();
}
private static final Breakpoint BUILDER_INSTANCE = new Breakpoint();
private final SuspendAnchor suspendAnchor;
private final BreakpointLocation locationKey;
private final boolean oneShot;
private final BreakpointExceptionFilter exceptionFilter;
private final ResolveListener resolveListener;
private volatile Debugger debugger;
private final List sessions = new LinkedList<>();
private volatile Assumption sessionsUnchanged;
private volatile boolean enabled;
private volatile boolean resolved;
private volatile int ignoreCount;
private volatile boolean disposed;
private volatile String condition;
private volatile boolean global;
private volatile GlobalBreakpoint roWrapper;
/* We use long instead of int in the implementation to avoid not hitting again on overflows. */
private final AtomicLong hitCount = new AtomicLong();
private volatile Assumption conditionUnchanged;
private volatile Assumption conditionExistsUnchanged;
private volatile EventBinding breakpointBinding;
private EventBinding sourceBinding;
Breakpoint(BreakpointLocation key, SuspendAnchor suspendAnchor) {
this(key, suspendAnchor, false, null, null);
}
private Breakpoint(BreakpointLocation key, SuspendAnchor suspendAnchor, boolean oneShot, BreakpointExceptionFilter exceptionFilter, ResolveListener resolveListener) {
this.locationKey = key;
this.suspendAnchor = suspendAnchor;
this.oneShot = oneShot;
this.exceptionFilter = exceptionFilter;
this.resolveListener = resolveListener;
this.enabled = true;
}
private Breakpoint() {
this.locationKey = null;
this.suspendAnchor = SuspendAnchor.BEFORE;
this.oneShot = false;
this.exceptionFilter = null;
this.resolveListener = null;
}
/**
* Returns the kind of this breakpoint.
*
* @since 1.0
*/
public Kind getKind() {
if (locationKey == null) {
return Kind.HALT_INSTRUCTION;
} else if (exceptionFilter == null) {
return Kind.SOURCE_LOCATION;
} else {
return Kind.EXCEPTION;
}
}
/**
* @return whether this breakpoint is permanently unable to affect execution
* @see #dispose()
*
* @since 0.17
*/
public boolean isDisposed() {
return disposed;
}
/**
* @return whether this breakpoint is currently allowed to suspend execution (true by default)
* @see #setEnabled(boolean)
*
* @since 0.9
*/
public boolean isEnabled() {
return enabled;
}
/**
* Controls whether this breakpoint is currently allowed to suspend execution (true by default).
* This can be changed arbitrarily until breakpoint is {@linkplain #dispose() disposed}.
*
* When not {@link #isModifiable() modifiable}, {@link IllegalStateException} is thrown.
*
* @param enabled whether this breakpoint should be allowed to suspend execution
*
* @since 0.9
*/
public synchronized void setEnabled(boolean enabled) {
if (disposed) {
// cannot enable disposed breakpoints
return;
}
if (this.enabled != enabled) {
if (!sessions.isEmpty()) {
if (enabled) {
install();
} else {
uninstall();
}
}
this.enabled = enabled;
}
}
/**
* @return whether at least one source has been loaded that contains a match for this
* breakpoint's location.
*
* @since 0.17
*/
public boolean isResolved() {
return resolved;
}
/**
* Assigns to this breakpoint a boolean expression whose evaluation will determine whether the
* breakpoint suspends execution (i.e. "hits"), {@code null} to remove any condition and always
* suspend.
*
* Breakpoints are by default unconditional.
*
*
* Evaluation: expressions are parsed and evaluated in the lexical context of
* the breakpoint's location. A conditional breakpoint that applies to multiple code locations
* will be parsed and evaluated separately for each location.
*
*
* Evaluation failure: when evaluation of a condition fails for any reason,
* including the return of a non-boolean value:
*
* - execution suspends, as if evaluation had returned {@code true}, and
* - a message is logged that can be
* {@linkplain SuspendedEvent#getBreakpointConditionException(Breakpoint) retrieved} while
* execution is suspended.
*
* When not {@link #isModifiable() modifiable}, {@link IllegalStateException} is thrown.
*
* @param expression if non{@code -null}, a boolean expression, expressed in the guest language
* of the breakpoint's location.
* @see SuspendedEvent#getBreakpointConditionException(Breakpoint)
*
* @since 0.9
*/
public synchronized void setCondition(String expression) {
boolean existsChanged = (this.condition == null) != (expression == null);
this.condition = expression;
Assumption assumption = conditionUnchanged;
if (assumption != null) {
this.conditionUnchanged = null;
assumption.invalidate();
}
if (existsChanged) {
assumption = conditionExistsUnchanged;
if (assumption != null) {
this.conditionExistsUnchanged = null;
assumption.invalidate();
}
}
}
/**
* Returns the expression used to create the current breakpoint condition, null if no condition
* set.
*
* @since 0.20
*/
@SuppressFBWarnings("UG")
public String getCondition() {
return condition;
}
/**
* Permanently prevents this breakpoint from affecting execution. When not
* {@link #isModifiable() modifiable}, {@link IllegalStateException} is thrown.
*
* @since 0.9
*/
public synchronized void dispose() {
if (!disposed) {
setEnabled(false);
if (sourceBinding != null) {
sourceBinding.dispose();
sourceBinding = null;
}
for (DebuggerSession session : sessions) {
session.disposeBreakpoint(this);
}
if (debugger != null) {
debugger.disposeBreakpoint(this);
debugger = null;
}
disposed = true;
}
}
/**
* @return whether this breakpoint disables itself after suspending execution, i.e. on first hit
*
* @since 0.9
*/
public boolean isOneShot() {
return oneShot;
}
/**
* @return the number of times breakpoint will be executed but not hit (i.e. suspend execution).
* @see #setIgnoreCount(int)
*
* @since 0.9
*/
public int getIgnoreCount() {
return ignoreCount;
}
/**
* Changes the number of times the breakpoint must be executed before it hits (i.e. suspends
* execution).
*
* When a breakpoint {@linkplain #setCondition(String) condition} evaluates to {@code false}:
*
* - execution is not suspended
* - it does not count as a hit
* - the remaining {@code ignoreCount} does not change.
*
* When not {@link #isModifiable() modifiable}, {@link IllegalStateException} is thrown.
*
* @param ignoreCount number of breakpoint activations to ignore before it hits
*
* @since 0.9
*/
public void setIgnoreCount(int ignoreCount) {
this.ignoreCount = ignoreCount;
}
/**
* @return the number of times this breakpoint has suspended execution
*
* @since 0.9
*/
public int getHitCount() {
return (int) hitCount.get();
}
/**
* @return a description of this breakpoint's specified location
*
* @since 0.9
*/
public String getLocationDescription() {
return locationKey.toString();
}
/**
* Returns the suspended position within the guest language source location.
*
* @since 0.32
*/
public SuspendAnchor getSuspendAnchor() {
return suspendAnchor;
}
/**
* Test whether this breakpoint can be modified. When false, methods that change
* breakpoint state throw {@link IllegalStateException}.
*
* Unmodifiable breakpoints are created from installed breakpoints as read-only copies to be
* available to clients other than the one who installed the original breakpoint.
* {@link Debugger#getBreakpoints()} returns unmodifiable breakpoints, for instance.
*
* @return whether this breakpoint can be modified.
* @since 0.27
*/
public boolean isModifiable() {
return true;
}
/**
* {@inheritDoc}
*
* @since 0.9
*/
@Override
public String toString() {
return getClass().getSimpleName() + "@" + Integer.toHexString(hashCode());
}
DebuggerNode lookupNode(EventContext context) {
if (!isEnabled()) {
return null;
} else {
EventBinding binding = breakpointBinding;
if (binding != null) {
return (DebuggerNode) context.lookupExecutionEventNode(binding);
}
return null;
}
}
private synchronized Assumption getConditionUnchanged() {
if (conditionUnchanged == null) {
conditionUnchanged = Truffle.getRuntime().createAssumption("Breakpoint condition unchanged.");
}
return conditionUnchanged;
}
private synchronized Assumption getConditionExistsUnchanged() {
if (conditionExistsUnchanged == null) {
conditionExistsUnchanged = Truffle.getRuntime().createAssumption("Breakpoint condition existence unchanged.");
}
return conditionExistsUnchanged;
}
synchronized void installGlobal(Debugger d) {
if (disposed) {
throw new IllegalArgumentException("Cannot install breakpoint, it is disposed already.");
}
if (this.debugger != null) {
throw new IllegalStateException("Breakpoint is already installed in a Debugger instance.");
}
install(d);
this.global = true;
}
private void install(Debugger d) {
assert Thread.holdsLock(this);
if (this.debugger != null && this.debugger != d) {
throw new IllegalStateException("Breakpoint is already installed in a different Debugger instance.");
}
this.debugger = d;
if (exceptionFilter != null) {
exceptionFilter.setDebugger(d);
}
}
synchronized boolean install(DebuggerSession d, boolean failOnError) {
if (disposed) {
if (failOnError) {
throw new IllegalArgumentException("Cannot install breakpoint, it is disposed already.");
} else {
return false;
}
}
if (this.sessions.contains(d)) {
if (failOnError) {
throw new IllegalStateException("Breakpoint is already installed in the session.");
} else {
return true;
}
}
install(d.getDebugger());
this.sessions.add(d);
sessionsAssumptionInvalidate();
if (enabled) {
install();
}
return true;
}
private void install() {
assert Thread.holdsLock(this);
SourceFilter filter;
if (sourceBinding == null && (filter = locationKey.createSourceFilter()) != null) {
final boolean[] sourceResolved = new boolean[]{false};
sourceBinding = debugger.getInstrumenter().attachExecuteSourceListener(filter, new ExecuteSourceListener() {
@Override
public void onExecute(ExecuteSourceEvent event) {
if (sourceResolved[0]) {
return;
}
sourceResolved[0] = true;
synchronized (Breakpoint.this) {
if (sourceBinding != null) {
sourceBinding.dispose();
}
}
Source source = event.getSource();
SourceSection location = locationKey.adjustLocation(source, debugger.getEnv(), suspendAnchor);
if (location != null) {
resolveBreakpoint(location);
}
SourceSectionFilter locationFilter = locationKey.createLocationFilter(source, suspendAnchor);
breakpointBinding = createBinding(locationFilter);
}
}, true);
if (sourceResolved[0]) {
sourceBinding.dispose();
}
} else if (breakpointBinding == null && (sourceBinding == null || sourceBinding.isDisposed())) {
// re-installing breakpoint
resolved = true;
SourceSectionFilter locationFilter = locationKey.createLocationFilter(null, suspendAnchor);
breakpointBinding = createBinding(locationFilter);
}
}
private EventBinding createBinding(SourceSectionFilter locationFilter) {
EventBinding binding = debugger.getInstrumenter().attachExecutionEventFactory(locationFilter, new BreakpointNodeFactory());
synchronized (this) {
for (DebuggerSession s : sessions) {
s.allBindings.add(binding);
}
}
return binding;
}
boolean isGlobal() {
return global;
}
synchronized void sessionClosed(DebuggerSession d) {
this.sessions.remove(d);
sessionsAssumptionInvalidate();
if (this.sessions.isEmpty()) {
uninstall();
}
}
private void sessionsAssumptionInvalidate() {
assert Thread.holdsLock(this);
Assumption assumption = sessionsUnchanged;
if (assumption != null) {
this.sessionsUnchanged = null;
assumption.invalidate();
}
}
private void resolveBreakpoint(SourceSection resolvedLocation) {
boolean notifyResolved = false;
synchronized (this) {
if (disposed) {
// cannot resolve disposed breakpoint
return;
}
if (!isResolved()) {
notifyResolved = true;
resolved = true;
}
}
if (notifyResolved && resolveListener != null) {
resolveListener.breakpointResolved(Breakpoint.this, resolvedLocation);
}
}
private void uninstall() {
assert Thread.holdsLock(this);
EventBinding binding = breakpointBinding;
breakpointBinding = null;
for (DebuggerSession s : sessions) {
s.allBindings.remove(binding);
}
if (binding != null) {
binding.dispose();
}
resolved = false;
}
/**
* Returns true if it should appear in the breakpoints list.
*
* @throws BreakpointConditionFailure
*/
boolean notifyIndirectHit(DebuggerNode source, DebuggerNode node, MaterializedFrame frame, DebugException exception) throws BreakpointConditionFailure {
if (!isEnabled()) {
return false;
}
assert node.getBreakpoint() == this;
if (source != node) {
// We're testing a different breakpoint at the same location
if (!((AbstractBreakpointNode) node).testCondition(frame)) {
return false;
}
if (exceptionFilter != null && exception != null) {
Throwable throwable = (Throwable) exception.getTruffleException();
assert throwable != null;
BreakpointExceptionFilter.Match matched = exceptionFilter.matchException(node, throwable);
if (!matched.isMatched) {
return false;
}
}
if (this.hitCount.incrementAndGet() <= ignoreCount) {
// breakpoint hit was ignored
return false;
}
}
if (isOneShot()) {
setEnabled(false);
}
return true;
}
@TruffleBoundary
private void doBreak(DebuggerNode source, DebuggerSession[] breakInSessions, MaterializedFrame frame, boolean onEnter, Object result, Throwable exception, BreakpointConditionFailure failure) {
DebugException de;
if (exception != null) {
de = new DebugException(debugger, (TruffleException) exception, null, source, false, null);
} else {
de = null;
}
doBreak(source, breakInSessions, frame, onEnter, result, de, failure);
}
@TruffleBoundary
private void doBreak(DebuggerNode source, DebuggerSession[] breakInSessions, MaterializedFrame frame, boolean onEnter, Object result, DebugException exception,
BreakpointConditionFailure failure) {
if (!isEnabled()) {
// make sure we do not cause break events if we got disabled already
// the instrumentation framework will make sure that this is not happening if the
// binding was disposed.
return;
}
if (this.hitCount.incrementAndGet() <= ignoreCount) {
// breakpoint hit was ignored
return;
}
SuspendAnchor anchor = onEnter ? SuspendAnchor.BEFORE : SuspendAnchor.AFTER;
for (DebuggerSession session : breakInSessions) {
if (session.isBreakpointsActive(getKind())) {
session.notifyCallback(source, frame, anchor, null, result, exception, failure);
}
}
}
Breakpoint getROWrapper() {
assert global; // wrappers are for global breakpoints only
GlobalBreakpoint wrapper = roWrapper;
if (wrapper == null) {
synchronized (this) {
wrapper = roWrapper;
if (wrapper == null) {
roWrapper = wrapper = new GlobalBreakpoint(this);
}
}
}
return wrapper;
}
/**
* Creates a new breakpoint builder based on a URI location.
*
* @param sourceUri a URI to specify breakpoint location
*
* @since 0.17
*/
public static Builder newBuilder(URI sourceUri) {
return BUILDER_INSTANCE.new Builder(sourceUri);
}
/**
* Creates a new breakpoint builder based on a {@link Source}.
*
* @param source a {@link Source} to specify breakpoint location
*
* @since 0.17
*/
public static Builder newBuilder(Source source) {
return BUILDER_INSTANCE.new Builder(source);
}
/**
* Creates a new breakpoint builder based on the textual region of a guest language source
* element.
*
* @param sourceSection a specification for guest language source element
*
* @since 0.17
*/
public static Builder newBuilder(SourceSection sourceSection) {
return BUILDER_INSTANCE.new Builder(sourceSection);
}
/**
* Creates a new exception breakpoint builder. The exception breakpoint can be set to intercept
* caught or uncaught exceptions, or both. At least one argument needs to be true. The builder
* creates {@link Breakpoint breakpoint} of {@link Kind#EXCEPTION EXCEPTION} kind.
*
* @param caught true to intercept exceptions that are caught by guest language
* code.
* @param uncaught true to intercept exceptions that are not caught by guest
* language code.
* @since 1.0
*/
public static ExceptionBuilder newExceptionBuilder(boolean caught, boolean uncaught) {
if (!(caught || uncaught)) {
throw new IllegalArgumentException("At least one of 'caught' or 'uncaught' needs to be true.");
}
return BUILDER_INSTANCE.new ExceptionBuilder(caught, uncaught);
}
/**
* Builder implementation for a new {@link Breakpoint breakpoint}.
*
* @see Breakpoint#newBuilder(Source)
* @see Breakpoint#newBuilder(URI)
* @see Breakpoint#newBuilder(SourceSection)
*
* @since 0.17
*/
public final class Builder {
private final Object key;
private int line = -1;
private SuspendAnchor anchor = SuspendAnchor.BEFORE;
private int column = -1;
private ResolveListener resolveListener;
private int ignoreCount;
private boolean oneShot;
private SourceSection sourceSection;
private SourceElement[] sourceElements;
private Builder(Object key) {
Objects.requireNonNull(key);
this.key = key;
}
private Builder(SourceSection key) {
this(key.getSource());
Objects.requireNonNull(key);
sourceSection = key;
}
/**
* Specifies the breakpoint's line number.
*
* Can only be invoked once per builder. Cannot be used together with
* {@link Breakpoint#newBuilder(SourceSection)}.
*
* @param line 1-based line number
* @throws IllegalStateException if {@code line < 1}
*
* @since 0.17
*/
public Builder lineIs(@SuppressWarnings("hiding") int line) {
if (line <= 0) {
throw new IllegalArgumentException("Line argument must be > 0.");
}
if (this.line != -1) {
throw new IllegalStateException("LineIs can only be called once per breakpoint builder.");
}
if (sourceSection != null) {
throw new IllegalArgumentException("LineIs cannot be used with source section based breakpoint. ");
}
this.line = line;
return this;
}
/**
* Specify the breakpoint suspension anchor within the guest language source location. By
* default, the breakpoint suspends {@link SuspendAnchor#BEFORE before} the source location.
*
* @param anchor the breakpoint suspension anchor
* @since 0.32
*/
public Builder suspendAnchor(@SuppressWarnings("hiding") SuspendAnchor anchor) {
this.anchor = anchor;
return this;
}
/**
* Specifies the breakpoint's column number.
*
* Can only be invoked once per builder. Cannot be used together with
* {@link Breakpoint#newBuilder(SourceSection)}. A line needs to be specified before a
* column can be set.
*
* @param column 1-based column number
* @throws IllegalStateException if {@code column < 1}
*
* @since 0.33
*/
public Builder columnIs(@SuppressWarnings("hiding") int column) {
if (column <= 0) {
throw new IllegalArgumentException("Column argument must be > 0.");
}
if (this.line == -1) {
throw new IllegalStateException("ColumnIs can only be called after a line is set.");
}
this.column = column;
return this;
}
/**
* Set a resolve listener. The listener is called when the breakpoint is resolved at the
* target location. A breakpoint is not resolved till the target source section is loaded.
* The target resolved location may differ from the specified {@link #lineIs(int) line} and
* {@link #columnIs(int) column}.
*
* @since 0.33
*/
public Builder resolveListener(@SuppressWarnings("hiding") ResolveListener resolveListener) {
Objects.requireNonNull(resolveListener);
if (this.resolveListener != null) {
throw new IllegalStateException("ResolveListener can only be set once per breakpoint builder.");
}
this.resolveListener = resolveListener;
return this;
}
/**
* Specifies the number of times a breakpoint is ignored until it hits (i.e. suspends
* execution}.
*
* @see Breakpoint#setIgnoreCount(int)
*
* @since 0.17
*/
public Builder ignoreCount(@SuppressWarnings("hiding") int ignoreCount) {
if (ignoreCount < 0) {
throw new IllegalArgumentException("IgnoreCount argument must be >= 0.");
}
this.ignoreCount = ignoreCount;
return this;
}
/**
* Specifies that the breakpoint will {@linkplain Breakpoint#setEnabled(boolean) disable}
* itself after suspending execution, i.e. on first hit.
*
* Disabled one-shot breakpoints can be {@linkplain Breakpoint#setEnabled(boolean)
* re-enabled}.
*
* @since 0.17
*/
public Builder oneShot() {
this.oneShot = true;
return this;
}
/**
* Specifies which source elements will this breakpoint adhere to. When not specified,
* breakpoint adhere to {@link SourceElement#STATEMENT} elements. Can only be invoked once
* per builder.
*
* @param sourceElements a non-empty list of source elements
* @since 0.33
*/
public Builder sourceElements(@SuppressWarnings("hiding") SourceElement... sourceElements) {
if (this.sourceElements != null) {
throw new IllegalStateException("Step source elements can only be set once per the builder.");
}
if (sourceElements.length == 0) {
throw new IllegalArgumentException("At least one source element needs to be provided.");
}
this.sourceElements = sourceElements;
return this;
}
/**
* @return a new breakpoint instance of {@link Kind#SOURCE_LOCATION SOURCE_LOCATION} kind.
*
* @since 0.17
*/
public Breakpoint build() {
if (sourceElements == null) {
sourceElements = new SourceElement[]{SourceElement.STATEMENT};
}
BreakpointLocation location;
if (sourceSection != null) {
location = BreakpointLocation.create(key, sourceElements, sourceSection);
} else {
location = BreakpointLocation.create(key, sourceElements, line, column);
}
Breakpoint breakpoint = new Breakpoint(location, anchor, oneShot, null, resolveListener);
breakpoint.setIgnoreCount(ignoreCount);
return breakpoint;
}
}
/**
* Builder implementation for a new {@link Breakpoint breakpoint} of {@link Kind#EXCEPTION
* EXCEPTION} kind.
*
* @see Breakpoint#newExceptionBuilder(boolean, boolean)
* @since 1.0
*/
public final class ExceptionBuilder {
private final boolean caught;
private final boolean uncaught;
private SuspensionFilter suspensionFilter;
private SourceElement[] sourceElements;
ExceptionBuilder(boolean caught, boolean uncaught) {
this.caught = caught;
this.uncaught = uncaught;
}
/**
* A filter to limit source locations which intercept exceptions. Only the source locations
* matching the filter will report thrown exceptions.
*
* @since 1.0
*/
public ExceptionBuilder suspensionFilter(SuspensionFilter filter) {
this.suspensionFilter = filter;
return this;
}
/**
* Specifies which source elements will this breakpoint adhere to. When not specified,
* breakpoint adhere to {@link SourceElement#STATEMENT} elements. Can only be invoked once
* per builder.
*
* @param sourceElements a non-empty list of source elements
* @since 1.0
*/
public ExceptionBuilder sourceElements(@SuppressWarnings("hiding") SourceElement... sourceElements) {
if (this.sourceElements != null) {
throw new IllegalStateException("Step source elements can only be set once per the builder.");
}
if (sourceElements.length == 0) {
throw new IllegalArgumentException("At least one source element needs to be provided.");
}
this.sourceElements = sourceElements.clone();
return this;
}
/**
* @return a new breakpoint instance of {@link Kind#EXCEPTION EXCEPTION} kind.
*
* @since 1.0
*/
public Breakpoint build() {
if (sourceElements == null) {
sourceElements = new SourceElement[]{SourceElement.STATEMENT};
}
BreakpointLocation location = BreakpointLocation.create(sourceElements, suspensionFilter);
BreakpointExceptionFilter efilter = new BreakpointExceptionFilter(caught, uncaught);
return new Breakpoint(location, SuspendAnchor.AFTER, false, efilter, null);
}
}
/**
* This listener is called when a breakpoint is resolved at the target location. The breakpoint
* is not resolved till the target source section is loaded. The target resolved location may
* differ from the specified breakpoint location.
*
* @since 0.33
*/
public interface ResolveListener {
/**
* Notify about a breakpoint resolved at the specified location.
*
* @param breakpoint The resolved breakpoint
* @param section The resolved location
* @since 0.33
*/
void breakpointResolved(Breakpoint breakpoint, SourceSection section);
}
private class BreakpointNodeFactory implements ExecutionEventNodeFactory {
@Override
public ExecutionEventNode create(EventContext context) {
if (!isResolved()) {
resolveBreakpoint(context.getInstrumentedSourceSection());
}
if (exceptionFilter != null) {
return new BreakpointAfterNodeException(Breakpoint.this, context);
}
switch (suspendAnchor) {
case BEFORE:
return new BreakpointBeforeNode(Breakpoint.this, context);
case AFTER:
return new BreakpointAfterNode(Breakpoint.this, context);
default:
throw new IllegalStateException("Unknown suspend anchor: " + suspendAnchor);
}
}
}
private static class BreakpointBeforeNode extends AbstractBreakpointNode {
BreakpointBeforeNode(Breakpoint breakpoint, EventContext context) {
super(breakpoint, context);
}
@Override
Set getSuspendAnchors() {
return DebuggerSession.ANCHOR_SET_BEFORE;
}
@Override
boolean isActiveAt(SuspendAnchor anchor) {
return SuspendAnchor.BEFORE == anchor;
}
@Override
protected void onEnter(VirtualFrame frame) {
onNode(frame, true, null, null);
}
}
private static class BreakpointAfterNode extends AbstractBreakpointNode {
BreakpointAfterNode(Breakpoint breakpoint, EventContext context) {
super(breakpoint, context);
}
@Override
Set getSuspendAnchors() {
return DebuggerSession.ANCHOR_SET_AFTER;
}
@Override
boolean isActiveAt(SuspendAnchor anchor) {
return SuspendAnchor.AFTER == anchor;
}
@Override
protected void onReturnValue(VirtualFrame frame, Object result) {
onNode(frame, false, result, null);
}
@Override
protected void onReturnExceptional(VirtualFrame frame, Throwable exception) {
if (exception instanceof TruffleException) {
onNode(frame, false, null, exception);
}
}
}
private static class BreakpointAfterNodeException extends AbstractBreakpointNode {
BreakpointAfterNodeException(Breakpoint breakpoint, EventContext context) {
super(breakpoint, context);
}
@Override
Set getSuspendAnchors() {
return DebuggerSession.ANCHOR_SET_AFTER;
}
@Override
boolean isActiveAt(SuspendAnchor anchor) {
return SuspendAnchor.AFTER == anchor;
}
@Override
public void onEnter(VirtualFrame frame) {
getBreakpoint().exceptionFilter.resetReportedException();
}
@Override
public void onReturnValue(VirtualFrame frame, Object result) {
getBreakpoint().exceptionFilter.resetReportedException();
}
@Override
@ExplodeLoop
protected void onReturnExceptional(VirtualFrame frame, Throwable exception) {
if (exception instanceof TruffleException) {
DebuggerSession[] debuggerSessions = getSessions();
boolean active = false;
List nonDuplicateSessions = null;
for (DebuggerSession session : debuggerSessions) {
if (consumeIsDuplicate(session)) {
if (nonDuplicateSessions == null) {
if (debuggerSessions.length == 1) {
// This node is marked as duplicate in the only session
return;
}
}
nonDuplicateSessions = removeDuplicateSession(debuggerSessions, session, nonDuplicateSessions);
} else if (session.isBreakpointsActive(getBreakpoint().getKind())) {
active = true;
}
}
if (!active) {
return;
}
if (nonDuplicateSessions != null) {
if (nonDuplicateSessions.isEmpty()) {
return;
}
debuggerSessions = toSessionsArray(nonDuplicateSessions);
}
BreakpointExceptionFilter.Match matched = getBreakpoint().exceptionFilter.matchException(this, exception);
if (matched.isMatched) {
BreakpointConditionFailure conditionError = null;
try {
if (!testCondition(frame)) {
return;
}
} catch (BreakpointConditionFailure e) {
conditionError = e;
}
breakBranch.enter();
doBreak(frame.materialize(), debuggerSessions, conditionError, exception, matched);
}
}
}
@TruffleBoundary
void doBreak(MaterializedFrame frame, DebuggerSession[] debuggerSessions, BreakpointConditionFailure conditionError, Throwable exception, BreakpointExceptionFilter.Match matched) {
Node throwLocation = getContext().getInstrumentedNode();
DebugException de = new DebugException(getBreakpoint().debugger, (TruffleException) exception, null, throwLocation, matched.isCatchNodeComputed, matched.catchLocation);
getBreakpoint().doBreak(this, debuggerSessions, frame, false, null, de, conditionError);
}
}
private abstract static class AbstractBreakpointNode extends DebuggerNode {
private final Breakpoint breakpoint;
protected final BranchProfile breakBranch = BranchProfile.create();
@Child private ConditionalBreakNode breakCondition;
@CompilationFinal private Assumption conditionExistsUnchanged;
@CompilationFinal(dimensions = 1) private DebuggerSession[] sessions;
@CompilationFinal private Assumption sessionsUnchanged;
AbstractBreakpointNode(Breakpoint breakpoint, EventContext context) {
super(context);
this.breakpoint = breakpoint;
initializeSessions();
this.conditionExistsUnchanged = breakpoint.getConditionExistsUnchanged();
if (breakpoint.condition != null) {
this.breakCondition = new ConditionalBreakNode(context, breakpoint);
}
}
private void initializeSessions() {
CompilerAsserts.neverPartOfCompilation();
synchronized (breakpoint) {
this.sessions = breakpoint.sessions.toArray(new DebuggerSession[]{});
sessionsUnchanged = Truffle.getRuntime().createAssumption("Breakpoint sessions unchanged.");
breakpoint.sessionsUnchanged = sessionsUnchanged;
}
}
@Override
boolean isStepNode() {
return false;
}
@Override
Breakpoint getBreakpoint() {
return breakpoint;
}
@Override
EventBinding getBinding() {
return breakpoint.breakpointBinding;
}
@ExplodeLoop
protected final void onNode(VirtualFrame frame, boolean onEnter, Object result, Throwable exception) {
if (!sessionsUnchanged.isValid()) {
CompilerDirectives.transferToInterpreterAndInvalidate();
initializeSessions();
}
DebuggerSession[] debuggerSessions = sessions;
boolean active = false;
List sessionsWithUniqueNodes = null;
for (DebuggerSession session : debuggerSessions) {
if (consumeIsDuplicate(session)) {
if (sessionsWithUniqueNodes == null) {
if (debuggerSessions.length == 1) {
// This node is marked as duplicate in the only session that's there.
return;
}
}
sessionsWithUniqueNodes = removeDuplicateSession(debuggerSessions, session, sessionsWithUniqueNodes);
} else if (session.isBreakpointsActive(breakpoint.getKind())) {
active = true;
}
}
if (!active) {
return;
}
if (sessionsWithUniqueNodes != null) {
if (sessionsWithUniqueNodes.isEmpty()) {
return;
}
debuggerSessions = toSessionsArray(sessionsWithUniqueNodes);
}
if (!conditionExistsUnchanged.isValid()) {
CompilerDirectives.transferToInterpreterAndInvalidate();
if (breakpoint.condition != null) {
this.breakCondition = insert(new ConditionalBreakNode(context, breakpoint));
notifyInserted(this.breakCondition);
} else {
this.breakCondition = null;
}
conditionExistsUnchanged = breakpoint.getConditionExistsUnchanged();
}
BreakpointConditionFailure conditionError = null;
try {
if (!testCondition(frame)) {
return;
}
} catch (BreakpointConditionFailure e) {
conditionError = e;
}
breakBranch.enter();
breakpoint.doBreak(this, debuggerSessions, frame.materialize(), onEnter, result, exception, conditionError);
}
final DebuggerSession[] getSessions() {
if (!sessionsUnchanged.isValid()) {
CompilerDirectives.transferToInterpreterAndInvalidate();
initializeSessions();
}
return sessions;
}
boolean testCondition(VirtualFrame frame) throws BreakpointConditionFailure {
if (!conditionExistsUnchanged.isValid()) {
CompilerDirectives.transferToInterpreterAndInvalidate();
if (breakpoint.condition != null) {
this.breakCondition = insert(new ConditionalBreakNode(context, breakpoint));
notifyInserted(this.breakCondition);
} else {
this.breakCondition = null;
}
conditionExistsUnchanged = breakpoint.getConditionExistsUnchanged();
}
if (breakCondition != null) {
try {
return breakCondition.executeBreakCondition(frame, sessions);
} catch (Throwable e) {
CompilerDirectives.transferToInterpreter();
throw new BreakpointConditionFailure(breakpoint, e);
}
}
return true;
}
}
@TruffleBoundary
private static List removeDuplicateSession(DebuggerSession[] sessions, DebuggerSession session, List nonDuplicateSessionsList) {
List nonDuplicateSessions = nonDuplicateSessionsList;
if (nonDuplicateSessions == null) {
nonDuplicateSessions = new ArrayList<>(sessions.length);
for (DebuggerSession s : sessions) {
if (s != session) {
nonDuplicateSessions.add(s);
}
}
} else {
nonDuplicateSessions.remove(session);
}
return nonDuplicateSessions;
}
@TruffleBoundary
private static DebuggerSession[] toSessionsArray(List sessions) {
return sessions.toArray(new DebuggerSession[sessions.size()]);
}
static final class BreakpointConditionFailure extends SlowPathException {
private static final long serialVersionUID = 1L;
private final Breakpoint breakpoint;
BreakpointConditionFailure(Breakpoint breakpoint, Throwable cause) {
super(cause);
this.breakpoint = breakpoint;
}
public Breakpoint getBreakpoint() {
return breakpoint;
}
public Throwable getConditionFailure() {
return getCause();
}
}
private static class ConditionalBreakNode extends Node {
private static final Object[] EMPTY_ARRAY = new Object[0];
private final EventContext context;
private final Breakpoint breakpoint;
@Child private SetThreadSuspensionEnabledNode suspensionEnabledNode = SetThreadSuspensionEnabledNodeGen.create();
@Child private DirectCallNode conditionCallNode;
@Child private ExecutableNode conditionSnippet;
@CompilationFinal private Assumption conditionUnchanged;
ConditionalBreakNode(EventContext context, Breakpoint breakpoint) {
this.context = context;
this.breakpoint = breakpoint;
this.conditionUnchanged = breakpoint.getConditionUnchanged();
}
boolean executeBreakCondition(VirtualFrame frame, DebuggerSession[] sessions) {
if ((conditionSnippet == null && conditionCallNode == null) || !conditionUnchanged.isValid()) {
CompilerDirectives.transferToInterpreterAndInvalidate();
initializeConditional(frame.materialize());
}
Object result;
try {
suspensionEnabledNode.execute(false, sessions);
if (conditionSnippet != null) {
result = conditionSnippet.execute(frame);
} else {
result = conditionCallNode.call(EMPTY_ARRAY);
}
} finally {
suspensionEnabledNode.execute(true, sessions);
}
if (!(result instanceof Boolean)) {
CompilerDirectives.transferToInterpreter();
throw new IllegalArgumentException("Unsupported return type " + result + " in condition.");
}
return (Boolean) result;
}
private void initializeConditional(MaterializedFrame frame) {
Node instrumentedNode = context.getInstrumentedNode();
final RootNode rootNode = instrumentedNode.getRootNode();
if (rootNode == null) {
throw new IllegalStateException("Probe was disconnected from the AST.");
}
Source instrumentedSource = context.getInstrumentedSourceSection().getSource();
Source conditionSource;
synchronized (breakpoint) {
conditionSource = Source.newBuilder(breakpoint.condition).language(instrumentedSource.getLanguage()).mimeType(instrumentedSource.getMimeType()).name(
"breakpoint condition").build();
if (conditionSource == null) {
throw new IllegalStateException("Condition is not resolved " + rootNode);
}
conditionUnchanged = breakpoint.getConditionUnchanged();
}
ExecutableNode snippet = breakpoint.debugger.getEnv().parseInline(conditionSource, instrumentedNode, frame);
if (snippet != null) {
conditionSnippet = insert(snippet);
notifyInserted(snippet);
} else {
CallTarget callTarget = Debugger.ACCESSOR.parse(conditionSource, instrumentedNode, new String[0]);
conditionCallNode = insert(Truffle.getRuntime().createDirectCallNode(callTarget));
}
}
}
/**
* A read-only wrapper over "global" breakpoint installed on {@link Debugger}. Instances of this
* wrapper are for public access to global breakpoints.
*/
@SuppressWarnings("sync-override")
static final class GlobalBreakpoint extends Breakpoint {
private final Breakpoint delegate;
GlobalBreakpoint(Breakpoint delegate) {
this.delegate = delegate;
}
@Override
public void dispose() {
fail();
}
@Override
public void setCondition(String expression) {
fail();
}
@Override
public void setEnabled(boolean enabled) {
fail();
}
@Override
public void setIgnoreCount(int ignoreCount) {
fail();
}
private static void fail() {
throw new IllegalStateException("Unmodifiable breakpoint.");
}
@Override
public boolean isModifiable() {
return false;
}
@Override
public String getCondition() {
return delegate.getCondition();
}
@Override
public int getHitCount() {
return delegate.getHitCount();
}
@Override
public int getIgnoreCount() {
return delegate.getIgnoreCount();
}
@Override
public String getLocationDescription() {
return delegate.getLocationDescription();
}
@Override
public SuspendAnchor getSuspendAnchor() {
return delegate.getSuspendAnchor();
}
@Override
public boolean isDisposed() {
return delegate.isDisposed();
}
@Override
public boolean isEnabled() {
return delegate.isEnabled();
}
@Override
public boolean isOneShot() {
return delegate.isOneShot();
}
@Override
public boolean isResolved() {
return delegate.isResolved();
}
}
}
class BreakpointSnippets {
@SuppressFBWarnings("")
public void example() {
SuspendedCallback suspendedCallback = new SuspendedCallback() {
public void onSuspend(SuspendedEvent event) {
}
};
Source someCode = Source.newBuilder("").mimeType("").name("").build();
TruffleInstrument.Env instrumentEnvironment = null;
// @formatter:off
// BEGIN: BreakpointSnippets.example
try (DebuggerSession session = Debugger.find(instrumentEnvironment).
startSession(suspendedCallback)) {
// install breakpoint in someCode at line 3.
session.install(Breakpoint.newBuilder(someCode).
lineIs(3).build());
// install breakpoint for a URI at line 3
session.install(Breakpoint.newBuilder(someCode.getURI()).
lineIs(3).build());
}
// END: BreakpointSnippets.example
// @formatter:on
}
}