Commit 8052a90d authored by Bob Flavin's avatar Bob Flavin

Extended string concatenation code to handle arguments in 'new

StringBuilder()' constructer, ie  'new StringBuilder("str")' or 'new
StringBuilder(String.valueof(varName))' 
parent 3d20d7d3
......@@ -5,6 +5,7 @@ import jadx.core.dex.info.FieldInfo;
import jadx.core.dex.info.MethodInfo;
import jadx.core.dex.instructions.ArithNode;
import jadx.core.dex.instructions.ArithOp;
import jadx.core.dex.instructions.ConstStringNode;
import jadx.core.dex.instructions.IfNode;
import jadx.core.dex.instructions.IndexInsnNode;
import jadx.core.dex.instructions.InsnType;
......@@ -86,17 +87,6 @@ public class SimplifyVisitor extends AbstractVisitor {
}
break;
case MOVE:
InsnArg firstArg = insn.getArg(0);
if (firstArg.isLiteral()) {
InsnNode constInsn = new InsnNode(InsnType.CONST, 1);
constInsn.setResult(insn.getResult());
constInsn.addArg(firstArg);
constInsn.copyAttributesFrom(insn);
return constInsn;
}
break;
default:
break;
}
......@@ -134,30 +124,65 @@ public class SimplifyVisitor extends AbstractVisitor {
}
private static InsnNode convertInvoke(MethodNode mth, InsnNode insn) {
MethodInfo callMth = ((InvokeNode) insn).getCallMth();
if (callMth.getDeclClass().getFullName().equals(Consts.CLASS_STRING_BUILDER)
&& callMth.getShortId().equals(Consts.MTH_TOSTRING_SIGNATURE)
&& insn.getArg(0).isInsnWrap()) {
try {
List<InsnNode> chain = flattenInsnChain(insn);
if (chain.size() > 1 && chain.get(0).getType() == InsnType.CONSTRUCTOR) {
ConstructorInsn constr = (ConstructorInsn) chain.get(0);
if (constr.getClassType().getFullName().equals(Consts.CLASS_STRING_BUILDER)
&& constr.getArgsCount() == 0) {
int len = chain.size();
InsnNode concatInsn = new InsnNode(InsnType.STR_CONCAT, len - 1);
for (int i = 1; i < len; i++) {
concatInsn.addArg(chain.get(i).getArg(1));
}
concatInsn.setResult(insn.getResult());
return concatInsn;
}
}
} catch (Throwable e) {
LOG.debug("Can't convert string concatenation: {} insn: {}", mth, insn, e);
}
}
return null;
MethodInfo callMth = ((InvokeNode) insn).getCallMth();
// If this is a 'new StringBuilder(xxx).append(yyy).append(zzz).toString(),
// convert it to STRING_CONCAT pseudo instruction.
if (callMth.getDeclClass().getFullName().equals(Consts.CLASS_STRING_BUILDER)
&& callMth.getShortId().equals(Consts.MTH_TOSTRING_SIGNATURE)
&& insn.getArg(0).isInsnWrap()) {
try {
List<InsnNode> chain = flattenInsnChain(insn);
int constrIndex = -1; //RAF
// Case where new StringBuilder() is called with NO args (the entire
// string is created using .append() calls:
if (chain.size()>1 && chain.get(0).getType()==InsnType.CONSTRUCTOR) {
constrIndex = 0;
} else if (chain.size()>2 && chain.get(1).getType()==InsnType.CONSTRUCTOR) {
//RAF Case where the first string element is String arg to the
// new StringBuilder("xxx") constructor
constrIndex = 1;
} else if (chain.size()>3 && chain.get(2).getType()==InsnType.CONSTRUCTOR) {
//RAF Case where the first string element is String.valueOf() arg
// to the new StringBuilder(String.valueOf(zzz)) constructor
constrIndex = 2;
}
if (constrIndex != -1) { // If we found a CONSTRUCTOR, is it a StringBuilder?
ConstructorInsn constr = (ConstructorInsn) chain.get(constrIndex);
if (constr.getClassType().getFullName().equals(Consts.CLASS_STRING_BUILDER)) {
int len = chain.size(), argInd = 1;
InsnNode concatInsn = new InsnNode(InsnType.STR_CONCAT, len-1);
InsnNode argInsn;
if (constrIndex > 0) { // There was an arg to the StringBuilder constr
InsnWrapArg iwa;
if (constrIndex==2
&& (argInsn = chain.get(1)).getType()==InsnType.INVOKE
&& ((InvokeNode)argInsn).getCallMth().getName().compareTo("valueOf")==0) {
// The argument of new StringBuilder() is a String.valueOf(chainElement0)
iwa = (InsnWrapArg)argInsn.getArg(0);
argInd = 3; // Cause for loop below to skip to after the constructor
} else {
ConstStringNode csn = (ConstStringNode)chain.get(0);
iwa = new InsnWrapArg(csn);
argInd = 2; // Cause for loop below to skip to after the constructor
}
concatInsn.addArg(iwa);
}
for (; argInd < len; argInd++) { // Add the .append(xxx) arg string to concat
concatInsn.addArg(chain.get(argInd).getArg(1));
}
concatInsn.setResult(insn.getResult());
return concatInsn;
} // end of if constructor is for StringBuilder
} // end of if we found a constructor early in the chain
} catch (Throwable e) {
LOG.debug("Can't convert string concatenation: {} insn: {}", mth, insn, e);
}
}
return null;
}
private static InsnNode simplifyArith(InsnNode insn) {
......
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