Remove redundant NOPs during bytecode optimization.
NOP instruction is required iff one of the following is true:
(a) it is a first bytecode instruction in a try-catch block (JVM BE assumption);
(b) it is a sole bytecode instruction in a source code line (breakpoints on that line will not work).
All other NOP instructions can be removed.
Note that it doesn't really affect the performance for mature JVM implementations.
However, the perceived quality of the generated code is somewhat improved :).
Related: KT-15609
Revert changes for "tolerant to uninitialized values" in OptimizationBasicInterpreter:
this approach doesn't converge for some specific cases where local variable is reused
(e.g., in several inlined functions - see https://youtrack.jetbrains.com/issue/KT-15112).
Instead, treat fake always-false conditional jump in the beginning of the post-condition loop as a "reference point" for stack on loop break / continue.
This requires an extra abstraction layer in FixStackAnalyzer, since we can't perform fine-grain manipulations on Frames
(such as "combine frame C from local variables of frame A and stack of frame B").
NB additional NOPs will be generated for post-condition loops.
Should make a separate bytecode postprocessing pass to get rid of unnecessary NOPs
(several YT issues for perceived quality of the generated bytecode are about such NOPs).
Note that now DeserializedClassDescriptor.getSealedSubclasses works a lot
faster than before, for all newly compiled sealed classes except empty ones. It
may be optimized further if we look at the metadata version of the file the
class was loaded from, however it's not easy currently because
DeserializedClassDescriptor is declared in common (non-JVM) code and has no
direct access to the binary version information.
This will also allow to add a reflection API to get subclasses of a sealed
class
#KT-12795 Fixed
For special calls (when-expressions, if-expressions, etc.), do not attempt to
get type of the argument expression, which is the block with the callable
reference, instead get type of the callable reference itself. The difference
matters because for block expressions, a new lexical scope is created for each
getTypeInfo (see ExpressionTypingServices.getBlockReturnedType), and we do not
support rewrites of this value in the binding trace
#KT-12044 Fixed
Prepend the platform name to the diagnostic in a common module, which is
reported when sources of that common module are analyzed as a part of the
platform source set: "<!JVM:...!> ... <!>". Fix some existing tests, mostly by
adding "impl" to implementations
Denis Zharkov