Class Profiler

java.lang.Object
org.antlr.runtime.debug.BlankDebugEventListener
org.antlr.runtime.debug.Profiler
All Implemented Interfaces:
DebugEventListener
public class Profiler extends BlankDebugEventListener
Using the debug event interface, track what is happening in the parser and record statistics about the runtime.

  • Field Details

  • Constructor Details

    • Profiler

      public Profiler()

    • Profiler

      public Profiler(DebugParser parser)

  • Method Details

    • enterRule

      public void enterRule(String grammarFileName, String ruleName)
      Description copied from interface: DebugEventListener
      The parser has just entered a rule. No decision has been made about which alt is predicted. This is fired AFTER init actions have been executed. Attributes are defined and available etc... The grammarFileName allows composite grammars to jump around among multiple grammar files.
      Specified by:
      enterRule in interface DebugEventListener
      Overrides:
      enterRule in class BlankDebugEventListener

    • exitRule

      public void exitRule(String grammarFileName, String ruleName)
      Description copied from interface: DebugEventListener
      This is the last thing executed before leaving a rule. It is executed even if an exception is thrown. This is triggered after error reporting and recovery have occurred (unless the exception is not caught in this rule). This implies an "exitAlt" event. The grammarFileName allows composite grammars to jump around among multiple grammar files.
      Specified by:
      exitRule in interface DebugEventListener
      Overrides:
      exitRule in class BlankDebugEventListener

    • examineRuleMemoization

      public void examineRuleMemoization(IntStream input, int ruleIndex, int stopIndex, String ruleName)
      Track memoization; this is not part of standard debug interface but is triggered by profiling. Code gen inserts an override for this method in the recognizer, which triggers this method. Called from alreadyParsedRule().

    • memoize

      public void memoize(IntStream input, int ruleIndex, int ruleStartIndex, String ruleName)
      Warning: doesn't track success/failure, just unique recording event

    • location

      public void location(int line, int pos)
      Description copied from interface: DebugEventListener
      To watch a parser move through the grammar, the parser needs to inform the debugger what line/charPos it is passing in the grammar. For now, this does not know how to switch from one grammar to the other and back for island grammars etc... This should also allow breakpoints because the debugger can stop the parser whenever it hits this line/pos.
      Specified by:
      location in interface DebugEventListener
      Overrides:
      location in class BlankDebugEventListener

    • enterDecision

      public void enterDecision(int decisionNumber, boolean couldBacktrack)
      Description copied from interface: DebugEventListener
      Every decision, fixed k or arbitrary, has an enter/exit event so that a GUI can easily track what LT/consume events are associated with prediction. You will see a single enter/exit subrule but multiple enter/exit decision events, one for each loop iteration.
      Specified by:
      enterDecision in interface DebugEventListener
      Overrides:
      enterDecision in class BlankDebugEventListener

    • exitDecision

      public void exitDecision(int decisionNumber)
      Specified by:
      exitDecision in interface DebugEventListener
      Overrides:
      exitDecision in class BlankDebugEventListener

    • consumeToken

      public void consumeToken(Token token)
      Description copied from interface: DebugEventListener
      An input token was consumed; matched by any kind of element. Trigger after the token was matched by things like match(), matchAny().
      Specified by:
      consumeToken in interface DebugEventListener
      Overrides:
      consumeToken in class BlankDebugEventListener

    • inDecision

      public boolean inDecision()
      The parser is in a decision if the decision depth > 0. This works for backtracking also, which can have nested decisions.

    • consumeHiddenToken

      public void consumeHiddenToken(Token token)
      Description copied from interface: DebugEventListener
      An off-channel input token was consumed. Trigger after the token was matched by things like match(), matchAny(). (unless of course the hidden token is first stuff in the input stream).
      Specified by:
      consumeHiddenToken in interface DebugEventListener
      Overrides:
      consumeHiddenToken in class BlankDebugEventListener

    • LT

      public void LT(int i, Token t)
      Track refs to lookahead if in a fixed/nonfixed decision.
      Specified by:
      LT in interface DebugEventListener
      Overrides:
      LT in class BlankDebugEventListener

    • beginBacktrack

      public void beginBacktrack(int level)
      Track backtracking decisions. You'll see a fixed or cyclic decision and then a backtrack. enter rule ... enter decision LA and possibly consumes (for cyclic DFAs) begin backtrack level mark m rewind m end backtrack level, success exit decision ... exit rule
      Specified by:
      beginBacktrack in interface DebugEventListener
      Overrides:
      beginBacktrack in class BlankDebugEventListener

    • endBacktrack

      public void endBacktrack(int level, boolean successful)
      Successful or not, track how much lookahead synpreds use
      Specified by:
      endBacktrack in interface DebugEventListener
      Overrides:
      endBacktrack in class BlankDebugEventListener

    • mark

      public void mark(int i)
      Description copied from interface: DebugEventListener
      The parser is going to look arbitrarily ahead; mark this location, the token stream's marker is sent in case you need it.
      Specified by:
      mark in interface DebugEventListener
      Overrides:
      mark in class BlankDebugEventListener

    • rewind

      public void rewind(int i)
      Description copied from interface: DebugEventListener
      After an arbitrairly long lookahead as with a cyclic DFA (or with any backtrack), this informs the debugger that stream should be rewound to the position associated with marker.
      Specified by:
      rewind in interface DebugEventListener
      Overrides:
      rewind in class BlankDebugEventListener

    • rewind

      public void rewind()
      Description copied from interface: DebugEventListener
      Rewind to the input position of the last marker. Used currently only after a cyclic DFA and just before starting a sem/syn predicate to get the input position back to the start of the decision. Do not "pop" the marker off the state. mark(i) and rewind(i) should balance still.
      Specified by:
      rewind in interface DebugEventListener
      Overrides:
      rewind in class BlankDebugEventListener

    • currentDecision

      protected Profiler.DecisionEvent currentDecision()

    • recognitionException

      public void recognitionException(RecognitionException e)
      Description copied from interface: DebugEventListener
      A recognition exception occurred such as NoViableAltException. I made this a generic event so that I can alter the exception hierachy later without having to alter all the debug objects. Upon error, the stack of enter rule/subrule must be properly unwound. If no viable alt occurs it is within an enter/exit decision, which also must be rewound. Even the rewind for each mark must be unwount. In the Java target this is pretty easy using try/finally, if a bit ugly in the generated code. The rewind is generated in DFA.predict() actually so no code needs to be generated for that. For languages w/o this "finally" feature (C++?), the target implementor will have to build an event stack or something. Across a socket for remote debugging, only the RecognitionException data fields are transmitted. The token object or whatever that caused the problem was the last object referenced by LT. The immediately preceding LT event should hold the unexpected Token or char. Here is a sample event trace for grammar: b : C ({;}A|B) // {;} is there to prevent A|B becoming a set | D ; The sequence for this rule (with no viable alt in the subrule) for input 'c c' (there are 3 tokens) is: commence LT(1) enterRule b location 7 1 enter decision 3 LT(1) exit decision 3 enterAlt1 location 7 5 LT(1) consumeToken [c/<4>,1:0] location 7 7 enterSubRule 2 enter decision 2 LT(1) LT(1) recognitionException NoViableAltException 2 1 2 exit decision 2 exitSubRule 2 beginResync LT(1) consumeToken [c/<4>,1:1] LT(1) endResync LT(-1) exitRule b terminate
      Specified by:
      recognitionException in interface DebugEventListener
      Overrides:
      recognitionException in class BlankDebugEventListener

    • semanticPredicate

      public void semanticPredicate(boolean result, String predicate)
      Description copied from interface: DebugEventListener
      A semantic predicate was evaluate with this result and action text
      Specified by:
      semanticPredicate in interface DebugEventListener
      Overrides:
      semanticPredicate in class BlankDebugEventListener

    • terminate

      public void terminate()
      Description copied from interface: DebugEventListener
      Parsing is over; successfully or not. Mostly useful for telling remote debugging listeners that it's time to quit. When the rule invocation level goes to zero at the end of a rule, we are done parsing.
      Specified by:
      terminate in interface DebugEventListener
      Overrides:
      terminate in class BlankDebugEventListener

    • setParser

      public void setParser(DebugParser parser)

    • toNotifyString

      public String toNotifyString()

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • getReport

      public Profiler.ProfileStats getReport()

    • getDecisionStats

      public DoubleKeyMap<String, Integer, Profiler.DecisionDescriptor> getDecisionStats()

    • getDecisionEvents

      public List<Profiler.DecisionEvent> getDecisionEvents()

    • toString

      public static String toString(Profiler.ProfileStats stats)

    • getDecisionStatsDump

      public String getDecisionStatsDump()

    • trim

      protected int[] trim(int[] X, int n)

    • toArray

      protected int[] toArray(List<Integer> a)

    • getNumberOfHiddenTokens

      public int getNumberOfHiddenTokens(int i, int j)
      Get num hidden tokens between i..j inclusive

    • locationDescription

      protected String locationDescription()

    • locationDescription

      protected String locationDescription(String file, String rule, int line, int pos)