[Fb-contrib-commit] fb-contrib/src/com/mebigfatguy/fbcontrib/detect UnnecessaryStoreBeforeReturn.java,1.2,1.3

[Dave B. <dbr...@us...>]

Update of /cvsroot/fb-contrib/fb-contrib/src/com/mebigfatguy/fbcontrib/detect
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv17455/src/com/mebigfatguy/fbcontrib/detect

Modified Files:
	UnnecessaryStoreBeforeReturn.java 
Log Message:
remove false positives when the load (for the return) is a branch target.

Index: UnnecessaryStoreBeforeReturn.java
===================================================================
RCS file: /cvsroot/fb-contrib/fb-contrib/src/com/mebigfatguy/fbcontrib/detect/UnnecessaryStoreBeforeReturn.java,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -d -r1.2 -r1.3
--- UnnecessaryStoreBeforeReturn.java	3 Dec 2005 16:47:19 -0000	1.2
+++ UnnecessaryStoreBeforeReturn.java	4 Dec 2005 05:32:46 -0000	1.3
@@ -18,6 +18,9 @@
  */
 package com.mebigfatguy.fbcontrib.detect;
 
+import java.util.HashSet;
+import java.util.Set;
+
 import org.apache.bcel.classfile.Method;
 
 import edu.umd.cs.findbugs.BugInstance;
@@ -30,8 +33,27 @@
 	private static final int SEEN_NOTHING = 0;
 	private static final int SEEN_STORE = 1;
 	private static final int SEEN_LOAD = 2;
+	private static final Set<Integer> branchInstructions = new HashSet<Integer>();
+	static {
+		branchInstructions.add(new Integer(GOTO));
+		branchInstructions.add(new Integer(IFEQ));
+		branchInstructions.add(new Integer(IFNE));
+		branchInstructions.add(new Integer(IFLT));
+		branchInstructions.add(new Integer(IFGE));
+		branchInstructions.add(new Integer(IFGT));
+		branchInstructions.add(new Integer(IFLE));
+		branchInstructions.add(new Integer(IF_ICMPEQ));
+		branchInstructions.add(new Integer(IF_ICMPNE));
+		branchInstructions.add(new Integer(IF_ICMPLT));
+		branchInstructions.add(new Integer(IF_ICMPGE));
+		branchInstructions.add(new Integer(IF_ICMPGT));
+		branchInstructions.add(new Integer(IF_ICMPLE));
+		branchInstructions.add(new Integer(IF_ACMPEQ));
+		branchInstructions.add(new Integer(IF_ACMPNE));
+	}
 	
 	private BugReporter bugReporter;
+	private Set<Integer> branchTargets = new HashSet<Integer>();
 	private int state;
 	private int storeReg;
 	private int loadReg;
@@ -46,6 +68,7 @@
 	
 	public void visitMethod(Method obj) {
 		state = SEEN_NOTHING;
+		branchTargets.clear();
 	}
 	
 	public void sawOpcode(int seen) {
@@ -73,6 +96,11 @@
 			break;
 			
 			case SEEN_STORE:
+				if (branchTargets.contains(new Integer(getPC()))) {
+					seen = SEEN_NOTHING;
+					return;
+				}
+
 				if ((seen >= ILOAD) && (seen <= ALOAD)) {
 					loadReg = getRegisterOperand();
 					state = (storeReg == loadReg) ? SEEN_LOAD : SEEN_NOTHING;
@@ -105,6 +133,11 @@
 				state = SEEN_NOTHING;
 			break;
 		}
+		
+		if (branchInstructions.contains(new Integer(seen))) {
+			branchTargets.add(new Integer(getBranchTarget()));
+		}
+		
 	}
 
 }