1 files changed, 150 insertions, 0 deletions
diff --git a/third_party/java/proguard/proguard5.3.3/src/proguard/optimize/ParameterShrinker.java b/third_party/java/proguard/proguard5.3.3/src/proguard/optimize/ParameterShrinker.java
new file mode 100644
index 0000000000..8d6ff621f0
--- /dev/null
+++ b/third_party/java/proguard/proguard5.3.3/src/proguard/optimize/ParameterShrinker.java
@@ -0,0 +1,150 @@
+/*
+ * ProGuard -- shrinking, optimization, obfuscation, and preverification
+ *             of Java bytecode.
+ *
+ * Copyright (c) 2002-2017 Eric Lafortune @ GuardSquare
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program 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 for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+package proguard.optimize;
+
+import proguard.classfile.*;
+import proguard.classfile.attribute.*;
+import proguard.classfile.attribute.visitor.AttributeVisitor;
+import proguard.classfile.editor.VariableRemapper;
+import proguard.classfile.util.*;
+import proguard.classfile.visitor.MemberVisitor;
+import proguard.optimize.info.ParameterUsageMarker;
+
+/**
+ * This AttributeVisitor removes unused parameters from the code of the methods
+ * that it visits.
+ *
+ * @see ParameterUsageMarker
+ * @see MethodStaticizer
+ * @see MethodDescriptorShrinker
+ * @author Eric Lafortune
+ */
+public class ParameterShrinker
+extends      SimplifiedVisitor
+implements   AttributeVisitor
+{
+    //*
+    private static final boolean DEBUG = false;
+    /*/
+    private static       boolean DEBUG = System.getProperty("ps") != null;
+    //*/
+
+
+    private final MemberVisitor extraVariableMemberVisitor;
+
+    private final VariableRemapper variableRemapper = new VariableRemapper();
+
+
+    /**
+     * Creates a new ParameterShrinker.
+     */
+    public ParameterShrinker()
+    {
+        this(null);
+    }
+
+
+    /**
+     * Creates a new ParameterShrinker with an extra visitor.
+     * @param extraVariableMemberVisitor an optional extra visitor for all
+     *                                   removed parameters.
+     */
+    public ParameterShrinker(MemberVisitor extraVariableMemberVisitor)
+    {
+        this.extraVariableMemberVisitor = extraVariableMemberVisitor;
+    }
+
+
+    // Implementations for AttributeVisitor.
+
+    public void visitAnyAttribute(Clazz clazz, Attribute attribute) {}
+
+
+    public void visitCodeAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute)
+    {
+        // Get the original parameter size that was saved.
+        int oldParameterSize = ParameterUsageMarker.getParameterSize(method);
+
+        // Compute the new parameter size from the shrunk descriptor.
+        int newParameterSize =
+            ClassUtil.internalMethodParameterSize(method.getDescriptor(clazz),
+                                                  method.getAccessFlags());
+
+        if (oldParameterSize > newParameterSize)
+        {
+            // Get the total size of the local variable frame.
+            int maxLocals = codeAttribute.u2maxLocals;
+
+            if (DEBUG)
+            {
+                System.out.println("ParameterShrinker: "+clazz.getName()+"."+method.getName(clazz)+method.getDescriptor(clazz));
+                System.out.println("  Old parameter size = " + oldParameterSize);
+                System.out.println("  New parameter size = " + newParameterSize);
+                System.out.println("  Max locals         = " + maxLocals);
+            }
+
+            // Create a variable map.
+            int[] variableMap = new int[maxLocals];
+
+            // Move unused parameters right after the parameter block.
+            int usedParameterIndex   = 0;
+            int unusedParameterIndex = newParameterSize;
+            for (int parameterIndex = 0; parameterIndex < oldParameterSize; parameterIndex++)
+            {
+                // Is the variable required as a parameter?
+                if (ParameterUsageMarker.isParameterUsed(method, parameterIndex))
+                {
+                    // Keep the variable as a parameter.
+                    variableMap[parameterIndex] = usedParameterIndex++;
+                }
+                else
+                {
+                    if (DEBUG)
+                    {
+                        System.out.println("  Deleting parameter #"+parameterIndex);
+                    }
+
+                    // Shift the variable to the unused parameter block,
+                    // in case it is still used as a variable.
+                    variableMap[parameterIndex] = unusedParameterIndex++;
+
+                    // Visit the method, if required.
+                    if (extraVariableMemberVisitor != null)
+                    {
+                        method.accept(clazz, extraVariableMemberVisitor);
+                    }
+                }
+            }
+
+            // Fill out the remainder of the map.
+            for (int variableIndex = oldParameterSize; variableIndex < maxLocals; variableIndex++)
+            {
+                variableMap[variableIndex] = variableIndex;
+            }
+
+            // Set the map.
+            variableRemapper.setVariableMap(variableMap);
+
+            // Remap the variables.
+            variableRemapper.visitCodeAttribute(clazz, method, codeAttribute);
+        }
+    }
+}