We have seen a production case where one the of the virtual call receivers got folded into a constant null, and then C2 started doing uncommon traps to get to the exception path.

Simplest way to reproduce follows:

```
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Fork(1)
@Warmup(iterations = 3, time = 1, timeUnit = TimeUnit.SECONDS)
@Measurement(iterations = 3, time = 1, timeUnit = TimeUnit.SECONDS)
@State(Scope.Thread)
public class NullReceiver {

    static final Object CONSTANT_OBJ = null;

    @Benchmark
    public String test() {
        try {
            return CONSTANT_OBJ.toString();
        } catch (NullPointerException e) {
            return "Boo";
        }
    }
}
```

It produces the attached flamegraph: null-receiver-uncommon-trap.

`-XX:+TraceDeoptimization` on current mainline produces a stream of "deopt" events with reason=null_check action=none:

```
UNCOMMON TRAP method=org.openjdk.NullReceiver.test()Ljava/lang/String; bci=3 pc=0x00000001148506e8, relative_pc=0x0000000000000068, debug_id=0 compiler=c2 compile_id=727 (@0x00000001148506e8) thread=26115 reason=null_check action=none unloaded_class_index=-1 debug_id=0
DEOPT PACKING thread=0x00000001259ada10 vframeArray=0x000000015800c410
   Compiled frame (sp=0x0000000171959f40 unextended sp=0x0000000171959f40, fp=0x0000000171959ff0, real_fp=0x0000000171959f60, pc=0x00000001148506e8)
     nmethod6032 727 ! 4 org.openjdk.NullReceiver::test (11 bytes)
   Virtual frames (innermost/newest first):
      VFrame 0 (0x00000001258bec20) - org.openjdk.NullReceiver.test()Ljava/lang/String; - invokevirtual @ bci=3
```

I think it is from here:
 https://github.com/openjdk/jdk/blob/3f1d9c441ea98910d9483e133bccfac784db393d/src/hotspot/share/opto/callGenerator.cpp#L238-L240

Arguably, calling virtual methods on known-null receiver is an antipattern, which we can avoid by checking for receiver null-ness explicitly. But it can also be the result of optimizations, which lets compiler know about receiver null-const-ness. It might be good if we can avoid doing this uncommon-trap dance and "just" throw the exception directly, as long as it is easy to do.