java-defects4j-closure-127-unreachablecodeelimination

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Before…lines 1–163 unchanged (163 lines)
            (n.getNext() == null || n.getNext().isFunction())) {
165
          Preconditions.checkState(
              outEdges.get(0).getValue() == Branch.UNCOND);
          Node fallThrough = computeFollowing(n);
          Node nextCfgNode = outEdges.get(0).getDestination().getValue();
          if (nextCfgNode == fallThrough) {
            removeNode(n);
          }
        }
    }
  }
176
177
  private Node computeFollowing(Node n) {
    Node next = ControlFlowAnalysis.computeFollowNode(n);
    while (next != null && next.isBlock()) {
      if (next.hasChildren()) {
        next = next.getFirstChild();
…lines 183–251 unchanged (69 lines)

After…lines 1–163 unchanged (163 lines)
            (n.getNext() == null || n.getNext().isFunction())) {
165
          Preconditions.checkState(
              outEdges.get(0).getValue() == Branch.UNCOND);
          Node fallThrough = computeFollowing(n);
          Node nextCfgNode = outEdges.get(0).getDestination().getValue();
          if (nextCfgNode == fallThrough && !inFinally(n.getParent(), n)) {
            removeNode(n);
          }
        }
    }
  }
176
  private boolean inFinally(Node parent, Node child) {
    if (parent == null || parent.isFunction()) {
      return false;
    } else if (NodeUtil.isTryFinallyNode(parent, child)) {
      return true;
    } else {
      return inFinally(parent.getParent(), parent);
    }
  }
186
  private Node computeFollowing(Node n) {
    Node next = ControlFlowAnalysis.computeFollowNode(n);
    while (next != null && next.isBlock()) {
      if (next.hasChildren()) {
        next = next.getFirstChild();
…lines 192–260 unchanged (69 lines)

Before…lines 1–163 unchanged (163 lines)
            (n.getNext() == null || n.getNext().isFunction())) {
165
          Preconditions.checkState(
              outEdges.get(0).getValue() == Branch.UNCOND);
          Node fallThrough = computeFollowing(n);
          Node nextCfgNode = outEdges.get(0).getDestination().getValue();
          if (nextCfgNode == fallThrough) {
            removeNode(n);
          }
        }
    }
  }
176
177
  private Node computeFollowing(Node n) {
    Node next = ControlFlowAnalysis.computeFollowNode(n);
    while (next != null && next.isBlock()) {
      if (next.hasChildren()) {
        next = next.getFirstChild();
…lines 183–251 unchanged (69 lines)

After…lines 1–163 unchanged (163 lines)
            (n.getNext() == null || n.getNext().isFunction())) {
165
          Preconditions.checkState(
              outEdges.get(0).getValue() == Branch.UNCOND);
          Node fallThrough = computeFollowing(n);
          Node nextCfgNode = outEdges.get(0).getDestination().getValue();
          if (nextCfgNode == fallThrough && !inFinally(n.getParent(), n)) {
            removeNode(n);
          }
        }
    }
  }
176
  private boolean inFinally(Node parent, Node child) {
    if (parent == null || parent.isFunction()) {
      return false;
    } else if (NodeUtil.isTryFinallyNode(parent, child)) {
      return true;
    } else {
      return inFinally(parent.getParent(), parent);
    }
  }
186
  private Node computeFollowing(Node n) {
    Node next = ControlFlowAnalysis.computeFollowNode(n);
    while (next != null && next.isBlock()) {
      if (next.hasChildren()) {
        next = next.getFirstChild();
…lines 192–260 unchanged (69 lines)

Before…lines 1–163 unchanged (163 lines)
            (n.getNext() == null || n.getNext().isFunction())) {
165
          Preconditions.checkState(
              outEdges.get(0).getValue() == Branch.UNCOND);
          Node fallThrough = computeFollowing(n);
          Node nextCfgNode = outEdges.get(0).getDestination().getValue();
          if (nextCfgNode == fallThrough) {
            removeNode(n);
          }
        }
    }
  }
176
177
  private Node computeFollowing(Node n) {
    Node next = ControlFlowAnalysis.computeFollowNode(n);
    while (next != null && next.isBlock()) {
      if (next.hasChildren()) {
        next = next.getFirstChild();
…lines 183–251 unchanged (69 lines)

After…lines 1–163 unchanged (163 lines)
            (n.getNext() == null || n.getNext().isFunction())) {
165
          Preconditions.checkState(
              outEdges.get(0).getValue() == Branch.UNCOND);
          Node fallThrough = computeFollowing(n);
          Node nextCfgNode = outEdges.get(0).getDestination().getValue();
          if (nextCfgNode == fallThrough && !inFinally(n.getParent(), n)) {
            removeNode(n);
          }
        }
    }
  }
176
  private boolean inFinally(Node parent, Node child) {
    if (parent == null || parent.isFunction()) {
      return false;
    } else if (NodeUtil.isTryFinallyNode(parent, child)) {
      return true;
    } else {
      return inFinally(parent.getParent(), parent);
    }
  }
186
  private Node computeFollowing(Node n) {
    Node next = ControlFlowAnalysis.computeFollowNode(n);
    while (next != null && next.isBlock()) {
      if (next.hasChildren()) {
        next = next.getFirstChild();
…lines 192–260 unchanged (69 lines)

Before

program

package_declaration

package "package"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "jscomp"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "common"

. "."

identifier "base"

. "."

identifier "Preconditions"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "jscomp"

. "."

identifier "ControlFlowGraph"

. "."

identifier "Branch"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "jscomp"

. "."

identifier "NodeTraversal"

. "."

identifier "AbstractShallowCallback"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "jscomp"

. "."

identifier "NodeTraversal"

. "."

identifier "FunctionCallback"

; ";"

import_declaration (+22 nodes collapsed)

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "jscomp"

. "."

identifier "graph"

. "."

identifier "GraphReachability"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "rhino"

. "."

identifier "Node"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

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identifier "javascript"

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identifier "rhino"

. "."

identifier "Token"

; ";"

import_declaration

import "import"

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identifier "java"

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identifier "util"

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identifier "List"

; ";"

import_declaration

import "import"

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identifier "java"

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identifier "util"

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identifier "logging"

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identifier "Level"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "java"

. "."

identifier "util"

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identifier "logging"

. "."

identifier "Logger"

; ";"

block_comment "/**\n * Removes dead code from a parse tree. The kinds of dea"...

line_comment "// TODO(user): Besides dead code after returns, this pass re"...

line_comment "// code such as breaks/continues/returns and stms w/out side"...

line_comment "// These things don't require reachability info, consider ma"...

line_comment "// pass or putting them in some other, more related pass."

class_declaration

class "class"

identifier "UnreachableCodeElimination"

super_interfaces

implements "implements"

type_list

type_identifier "CompilerPass"

class_body

{ "{"

field_declaration (+27 nodes collapsed)

field_declaration

modifiers

private "private"

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identifier "compiler"

; ";"

field_declaration

modifiers

private "private"

final "final"

boolean_type "boolean"

variable_declarator

identifier "removeNoOpStatements"

; ";"

field_declaration

modifiers

private "private"

boolean_type "boolean"

variable_declarator

identifier "codeChanged"

; ";"

constructor_declaration (+33 nodes collapsed)

method_declaration (+212 nodes collapsed)

class_declaration

modifiers

private "private"

class "class"

identifier "EliminationPass"

superclass

extends "extends"

type_identifier "AbstractShallowCallback"

class_body

{ "{"

field_declaration

modifiers

private "private"

final "final"

generic_type

type_identifier "ControlFlowGraph"

type_arguments

< "<"

type_identifier "Node"

> ">"

variable_declarator

identifier "cfg"

; ";"

constructor_declaration (+27 nodes collapsed)

method_declaration (+155 nodes collapsed)

block_comment "/**\n * Tries to remove n if it is an unconditional branc"...

method_declaration

modifiers

annotation

@ "@"

identifier "SuppressWarnings"

annotation_argument_list

( "("

string_literal

" "\""

string_fragment "fallthrough"

" "\""

) ")"

private "private"

void_type "void"

identifier "tryRemoveUnconditionalBranching"

formal_parameters

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formal_parameter

type_identifier "Node"

identifier "n"

) ")"

block

{ "{"

block_comment "/*\n * For each unconditional branching control flow no"...

line_comment "// If n is null the target is the end of the function, nothi"...

if_statement

if "if"

parenthesized_expression

( "("

binary_expression

identifier "n"

== "=="

null_literal "null"

) ")"

block

{ "{"

return_statement

return "return"

; ";"

} "}"

local_variable_declaration (+21 nodes collapsed)

if_statement

if "if"

parenthesized_expression

( "("

binary_expression

identifier "gNode"

== "=="

null_literal "null"

) ")"

block

{ "{"

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; ";"

} "}"

switch_expression

switch "switch"

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( "("

method_invocation

identifier "n"

. "."

identifier "getType"

argument_list

( "("

) ")"

switch_block

{ "{"

switch_block_statement_group (+26 nodes collapsed)

switch_block_statement_group

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case "case"

field_access

identifier "Token"

. "."

identifier "BREAK"

: ":"

switch_block_statement_group

switch_label

case "case"

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identifier "Token"

. "."

identifier "CONTINUE"

: ":"

line_comment "// We are looking for a control flow changing statement that"...

line_comment "// branches to the same node. If after removing it control s"...

line_comment "// branches to the same node, it is safe to remove."

local_variable_declaration (+25 nodes collapsed)

if_statement

if "if"

parenthesized_expression (+44 nodes collapsed)

block

{ "{"

expression_statement (+29 nodes collapsed)

local_variable_declaration

type_identifier "Node"

variable_declarator

identifier "fallThrough"

= "="

method_invocation

identifier "computeFollowing"

argument_list

( "("

identifier "n"

) ")"

; ";"

local_variable_declaration (+26 nodes collapsed)

if_statement

if "if"

parenthesized_expression

( "("

binary_expression any 1:2

identifier "nextCfgNode"

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identifier "fallThrough"

) ")"

block

{ "{"

expression_statement

method_invocation

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argument_list

( "("

identifier "n"

) ")"

; ";"

} "}"

method_declaration (+95 nodes collapsed)

method_declaration (+246 nodes collapsed)

method_declaration (+98 nodes collapsed)

} "}"

After

program

package_declaration

package "package"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "jscomp"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "common"

. "."

identifier "base"

. "."

identifier "Preconditions"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "jscomp"

. "."

identifier "ControlFlowGraph"

. "."

identifier "Branch"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "jscomp"

. "."

identifier "NodeTraversal"

. "."

identifier "AbstractShallowCallback"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "jscomp"

. "."

identifier "NodeTraversal"

. "."

identifier "FunctionCallback"

; ";"

import_declaration (+22 nodes collapsed)

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "jscomp"

. "."

identifier "graph"

. "."

identifier "GraphReachability"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "rhino"

. "."

identifier "Node"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "com"

. "."

identifier "google"

. "."

identifier "javascript"

. "."

identifier "rhino"

. "."

identifier "Token"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "java"

. "."

identifier "util"

. "."

identifier "List"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "java"

. "."

identifier "util"

. "."

identifier "logging"

. "."

identifier "Level"

; ";"

import_declaration

import "import"

scoped_identifier

identifier "java"

. "."

identifier "util"

. "."

identifier "logging"

. "."

identifier "Logger"

; ";"

block_comment "/**\n * Removes dead code from a parse tree. The kinds of dea"...

line_comment "// TODO(user): Besides dead code after returns, this pass re"...

line_comment "// code such as breaks/continues/returns and stms w/out side"...

line_comment "// These things don't require reachability info, consider ma"...

line_comment "// pass or putting them in some other, more related pass."

class_declaration

class "class"

identifier "UnreachableCodeElimination"

super_interfaces

implements "implements"

type_list

type_identifier "CompilerPass"

class_body

{ "{"

field_declaration (+27 nodes collapsed)

field_declaration

modifiers

private "private"

final "final"

type_identifier "AbstractCompiler"

variable_declarator

identifier "compiler"

; ";"

field_declaration

modifiers

private "private"

final "final"

boolean_type "boolean"

variable_declarator

identifier "removeNoOpStatements"

; ";"

field_declaration

modifiers

private "private"

boolean_type "boolean"

variable_declarator

identifier "codeChanged"

; ";"

constructor_declaration (+33 nodes collapsed)

method_declaration (+212 nodes collapsed)

class_declaration

modifiers

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identifier "EliminationPass"

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type_identifier "AbstractShallowCallback"

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{ "{"

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type_arguments

< "<"

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variable_declarator

identifier "cfg"

; ";"

constructor_declaration (+27 nodes collapsed)

method_declaration (+155 nodes collapsed)

block_comment "/**\n * Tries to remove n if it is an unconditional branc"...

method_declaration

modifiers

annotation

@ "@"

identifier "SuppressWarnings"

annotation_argument_list

( "("

string_literal

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{ "{"

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{ "{"

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( "("

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identifier "n"

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line_comment "// branches to the same node, it is safe to remove."

local_variable_declaration (+25 nodes collapsed)

if_statement

if "if"

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block

{ "{"

expression_statement (+29 nodes collapsed)

local_variable_declaration

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variable_declarator

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argument_list

( "("

identifier "n"

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local_variable_declaration (+26 nodes collapsed)

if_statement

if "if"

parenthesized_expression

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{ "{"

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modifiers

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method_declaration (+95 nodes collapsed)

method_declaration (+246 nodes collapsed)

method_declaration (+98 nodes collapsed)

} "}"