Hi, occassionally I get errors like the following:
instruction type: class com.ibm.wala.classLoader.JavaLanguage$JavaInstructionFactory$10
call site: invokestatic < Application, Ljava/lang/invoke/LambdaMetafactory, metafactory(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite; >@20
caller: Node: < Application, Lru/saidgadjiev/ormnext/core/field/FieldAccessor, makeGetter(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/invoke/MethodHandle;)Ljava/util/function/Function; > Context: DelegatingContext [A=CallStringContext: [ com.ibm.wala.FakeRootClass.fakeRootMethod()V@4 ], B=Everywhere]
unexpected non-invokedynamic instruction!
Is there anything I can do about this?
With the changes in master I run into problems in my code.
fun SSAInvokeInstruction.getLambdaMethod(): IMethodName {
require(this.isLambdaMetafactoryInvoke()) { "instruction is not a call to LambdaMetafactory" }
require(this is SSAInvokeDynamicInstruction){"instruction is not a SSAInvokeDynamicInstruction: $this"} // here it fails
val cp = bootstrap.cp // <— how do I get access to the bootstrap? I’m looking for the method that get’s invoked.
val index = (0 until bootstrap.callArgumentCount()).first { bootstrap.callArgumentKind(it) == ClassConstants.CONSTANT_MethodHandle.toInt() }.let { bootstrap.callArgumentIndex(it) }
val methodName = "L${cp.getCPHandleClass(index)}.${cp.getCPHandleName(index)}${cp.getCPHandleType(index)}"
return VmMethodName.of(methodName)
}The cast fails (it’s not a SSAInvokeDynamic anymore). But w/o that cast i don’t get access to the bootstrap object. How would I solve this now?
invokedynamic is being used for more and more stuff, and it's hard to support arbitrary bootstrap methods, so we kind of play whack-a-mole with these issues
2 replies
Acyclic.computeBackEdges(callGraph, node), but I don’t know what do to with it
Hi, y'all. I am wondering if there are some code examples using WALA CAst for Java source code? In particular generating Call Graphs using it. Thanks!
@dtomassi this is the best example we have: https://github.com/wala/WALA/blob/master/com.ibm.wala.cast.java.ecj/src/main/java/com/ibm/wala/cast/java/ecj/util/SourceDirCallGraph.java Sorry, we need to make it more prominent in the documentation
22 replies
Hi all,
I am struggeling to traverse the controllflowgraph of an CGNode, in a way so that I can introspect each invocation/ instruction and get their node.
I imagine something like:
public static void main(String[] args) {
int x = 2;
x++;
if (true && 4 + 4 == 3)
throw new NullPointerException();
}In other words, how would I search through the graph and find the exception throwing, plus the expression in the if clause that is responsible for it?
Any help is welcome.
Hi all.
Thank you for your help in Issues the other day.
I have a question about the backward slice, so I ask it here.
I did some backward slicing on the following code, but I didn't get the results I expected.
The configuration is as follows.
- Slicer.DataDependenceOptions.FULL
- Slicer.ControlDependenceOptions.NO_EXCEPTIONAL_EDGES
- CallGraphBuilder: makeZeroOneContainerCFABuilder
- slice seed: Iterator.hasNest();
- java version: 1.8.0_211
- WALA version: 1.5.5
public class ArraySample {
public static void main(String[] args) {
List<Integer> list = new ArrayList<>();
list.add(1);
for (Integer str : list) {
System.out.println(str);
}
}
}Slice result:
0 = {NormalReturnCaller@2194} "NORMAL_RET_CALLER:Node: < Application, LArraySample, main([Ljava/lang/String;)V > Context: Everywhere[13]13 = invokeinterface < Application, Ljava/util/Iterator, hasNext()Z > 11 @27 exception:12"
1 = {NormalStatement@2195} "NORMAL hasNext:return 9 Node: < Primordial, Ljava/util/ArrayList$Itr, hasNext()Z > Context: DelegatingContext [A=ReceiverInstanceContext<SITE_IN_NODE{< Primordial, Ljava/util/ArrayList, iterator()Ljava/util/Iterator; >:NEW <Primordial,Ljava/util/ArrayList$Itr>@0 in DelegatingContext [A=ReceiverInstanceContext<SITE_IN_NODE{< Application, LArraySample, main([Ljava/lang/String;)V >:NEW <Application,Ljava/util/ArrayList>@0 in Everywhere}>, B=Everywhere]}>, B=Everywhere]"
2 = {PhiStatement@2196} "PHI Node: < Primordial, Ljava/util/ArrayList$Itr, hasNext()Z > Context: DelegatingContext [A=ReceiverInstanceContext<SITE_IN_NODE{< Primordial, Ljava/util/ArrayList, iterator()Ljava/util/Iterator; >:NEW <Primordial,Ljava/util/ArrayList$Itr>@0 in DelegatingContext [A=ReceiverInstanceContext<SITE_IN_NODE{< Application, LArraySample, main([Ljava/lang/String;)V >:NEW <Application,Ljava/util/ArrayList>@0 in Everywhere}>, B=Everywhere]}>, B=Everywhere]:9 = phi 8,7"
3 = {NormalReturnCallee@2197} "NORMAL_RET_CALLEE:Node: < Primordial, Ljava/util/ArrayList$Itr, hasNext()Z > Context: DelegatingContext [A=ReceiverInstanceContext<SITE_IN_NODE{< Primordial, Ljava/util/ArrayList, iterator()Ljava/util/Iterator; >:NEW <Primordial,Ljava/util/ArrayList$Itr>@0 in DelegatingContext [A=ReceiverInstanceContext<SITE_IN_NODE{< Application, LArraySample, main([Ljava/lang/String;)V >:NEW <Application,Ljava/util/ArrayList>@0 in Everywhere}>, B=Everywhere]}>, B=Everywhere]"The slice results I expect:
List<Integer> list = new ArrayList<>();
list.add(1);If an iterator is used, isn't a backward slice of the original object valid?
If so, how can I get the results I expect?
Could you give me some advice if convenient.
ArrayList even with no control dependence. But I'm not 100% sure. In any case I think it's worth reporting the issue
find() and then check the length of the returned List
https.get(..., function (r) { ... }), is it possible to use certain API to construct data-flow entering the callback's body? (assuming the model of https.get can be manually constructed using any approach)
https.get. In particular, our call graph construction accounts for inter-procedural data flow, and we have many frameworks that allow you to perform inter-procedural data flow analysis on top of a call graph
Hi, all.
I'd like to specify the definition of the arguments in a method call.
For example, the following code is assumed.
public class Main {
public static void main(String[] args) {
int x = 3;
branch(x);
}
private static void test(int x) {
for(int i = 0; i<x ; i++){
Syste.out.println("count");
}
}In this case, is it possible to specify the source of the definition of x, which is referenced in the test method?
One possible way is to use a backward slice with a conditional branch as the seed in a loop statement.
I would like to know if there is any other good way.
WALA has a way to do inter-procedural data flow analysis, but as far as I know, I am aware that it only works with static fields.
