Clean up code gen for method invocations

The code was patched many times in the history and became a bit
scattered.

When emitting a virtual call, the receiver in the bytecode cannot just
be the method's owner (the class in which it is declared), because that
class may not be accessible at the callsite. Instead we use the type
of the receiver. This was basically done to fix
  - aladdin bug 455 (9954eaf)
  - SI-1430 (0bea2ab) - basically the same bug, slightly different
  - SI-4283 (8707c9e) - the same for field reads

In this patch we extend the fix to field writes, and clean up the code.

This patch basically reverts 6eb55d4b, the fix for SI-4560, which was
rather a workaround than a fix. The underlying problem was that in some
cases, in a method invocation `foo.bar()`, the method `bar` was not
actually a member of `foo.tpe`, causing a NoSuchMethodErrors. The
issue was related to trait implementation classes. The idea of the fix
was to check, at code-gen time, `foo.tpe.member("bar")`, and if that
returns `NoSymbol`, use `barSym.owner`. With the new trait encoding
the underlying problem seems to be fixed - all tests still pass
(run/t4560.scala and run/t4560b.scala).

1 files changed, 6 insertions, 6 deletions

diff --git a/test/junit/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzerTest.scala b/test/junit/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzerTest.scala
index 78dbab82f4..ab05c15e85 100644
--- a/test/junit/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzerTest.scala
+++ b/test/junit/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzerTest.scala
@@ -68,12 +68,12 @@ class NullnessAnalyzerTest extends ClearAfterClass {
     // So in the frame for `ALOAD 0`, the stack is still empty.
 
     val res =
-      """                                                          L0: 0:  NotNull
-        |                                             LINENUMBER 1 L0: 0:  NotNull
-        |                                                     ALOAD 0: 0:  NotNull
-        |INVOKEVIRTUAL java/lang/Object.toString ()Ljava/lang/String;: 0:  NotNull, 1:  NotNull
-        |                                                     ARETURN: 0:  NotNull, 1: Unknown1
-        |                                                          L0: null""".stripMargin
+      """                                           L0: 0:  NotNull
+        |                              LINENUMBER 1 L0: 0:  NotNull
+        |                                      ALOAD 0: 0:  NotNull
+        |INVOKEVIRTUAL C.toString ()Ljava/lang/String;: 0:  NotNull, 1:  NotNull
+        |                                      ARETURN: 0:  NotNull, 1: Unknown1
+        |                                           L0: null""".stripMargin
 //    println(showAllNullnessFrames(newNullnessAnalyzer(m), m))
     assertEquals(showAllNullnessFrames(newNullnessAnalyzer(m), m), res)
   }