Unlike previously, this optimisation works on every callee return type.
Tail-calls inside unit functions can be either
INVOKE...
ARETURN
or
INVOKE
POP
GETSTATIC kotlin/Unit.INSTANCE
ARETURN
The first pattern is already covered. The second one is a bit tricky,
since we cannot just assume than the function is tail-call, we also need
to check whether the callee returned COROUTINE_SUSPENDED marker.
Thus, resulting bytecode of function's 'epilogue' look like
DUP
INVOKESTATIC getCOROUTINE_SUSPENDED
IF_ACMPNE LN
ARETURN
LN:
POP
#KT-28938 Fixed
coroutines intrinsic lambda.
The logic is if the lambda is crossinline we need to generate the
accessor. However, suspendCoroutine's and
suspendCoroutineUninterceptedOrReturn's parameter, despite being
crossinline, are effectively inline. Thus, we do not need to generate
the accessor.
#KT-27503 Fixed
Unfortunately this cannot currently be done for the extension overload which accepts a radix due to behavior difference with regard to invalid radix values.
- implement error result
- refactor other result classes
- implement handling in the script evaluation extension - also restores
previous script error reporting functionality
- add possibility to customize result fileds in script and REPL
- refactor result calculation in the backend: cleanup, rename (since
it is not only about REPL now)
In case the wrapped exception message contains some long text (bytecode,
IR, etc.), it could be displayed several times in the same stack trace,
which significantly worsened the experience of parsing such stack traces
Building on the work in #2403, shaves 1% of compilation time on kotlinx.serialization
by using SmartIdentityTable instead of hashMap in LabelNormailizationMethodTransformer.
Metrics on the prior hashMap use in this code:
| What | Count |
| --------- | ----- |
| instances | 21530 |
| min | 0 |
| max | 174 |
| mean | 4 |
| stddev | 8.24 |
| median | 4 |
| 90p | 8 |
| 95p | 15 |
Profiling the compilation of kotlinx.serialization, MaxStackFrameSizeAndLocalsCalculator
causes ~7% of the runtime to be spent in java.lang.Object.hashCode
This is through two uses:
- visitMaxs(..) has a pushed hashSet that causes ~2%
- labelWrappersMap used to attach additional data to asm Labels, causes ~ 5%
visitMaxs can use the existing SmartSet (not to be confused with SmartHashSet)
Analysis of the visitMaxs HashSet creation & sizes:
| What | Amount |
| calls to visitMaxs | 4416 |
| max pushed | 158 |
| median pushed | 4 |
| average pushed | 5.20 |
| stddev pushed | 7.66 |
| 90 percentile | 10 |
Analysis of labelWrappersMap creation & sizes:
| What | Amount |
| ------------------ | ------ |
| hashtables created | 4006 |
| max entries | 175 |
| median entries | 5 |
| average entries | 6.10 |
| stdev entries | 8.28 |
| 90 percentile | 11 |
testing with a non hash based map using an array for keys and an array for values
showed that the cost of MaxStackFrameSizeAndLocalsCalculator became neglible to
the overall running time.
SmartIdentityTable is a Map like structure that uses reference identity for keys.
It uses 2 arrays to store keys & values until the number of entries stored is larger than 10.
At that point it switches to using an IdentityHashMap.
This structure can be used instead of HashMap when reference identity can be used and
the number of entries inserted is small (<= 10) on average, drastically reducing the overhead
of calls to Object.hashCode
Between the two changes, compilation of kotlinx.serialization through kotlinc
commandline decreased from 14 seconds to 11 seconds on my machine
It's enough to have at least one good constraint.
Note that the whole algorithm can be a bit more general:
we could check also Out<T>, In<T> and verify that T has good only
lower constraint or upper constraint, but there are questions for
types like Inv<Out<T>>, where T should have lower and upper constraints
#KT-31514 Fixed
A synthetic property descriptor created for `B.value` (see the added
test) should not be equal to the normal descriptor created by the fake
override construction algorithm. Otherwise we can't reach this synthetic
non-abstract descriptor when building bridges in `C`, which results in
exception.
#KT-31367 Fixed
It uses isStaticMethod to determine whether to set ACC_STATIC, which is
not correct (see PR #2341). This results in using incorrectly typed
opcodes (as all arguments are shifted by 1) when modifying the inlined
lambda's bytecode. For example, in the test added by this commit, these
opcodes are inserted to spill the stack into locals before calling
another inline function.
Because getMethodAsmFlags is used by the non-IR backend (see PR #2341
again for why changing stuff might not be a good idea), the proposed
solution is to ditch it completely and override generateLambdaBody in
IrExpressionLambdaImpl to use FunctionCodegen's IR-based flag
computation logic.
Although the intention of the change 9894c216c1 (#2341) was sensible, it
unfortunately caused the type mapper to map a default method incorrectly
under certain _undiscovered_ circumstances, which leads to incorrect
bytecode being generated. Specifically, this led to an exception:
java.lang.NoSuchMethodError : org.jetbrains.kotlin.idea.debugger.evaluate.KotlinDebuggerCaches$Companion.compileCodeFragmentCacheAware$default(Lorg/jetbrains/kotlin/psi/KtCodeFragment;Lcom/intellij/debugger/SourcePosition;Lkotlin/jvm/functions/Function0;ZILjava/lang/Object;)Lkotlin/Pair;
in a developer branch where this class was refactored and moved to
another module. I was not able to determine the exact reason of this
error, so I'm workarounding it by limiting this change to the IR backend
only (where it's needed), and postponing the investigation of the
failure above for now.
The synthesized arguments caused the size of default value mask off by
one when it is close to the boundary of Int.SIZE, which in turn
resulted in wrong signature at call sites.
in OUTERCLASS field.
The inliner generates two versions of suspend functions/lambdas in
inline functions: with state-machine and without. The former is used
to call the function from Java or via reflection and have ordinary
name, while the latter is used by inliner and have $$forInline suffix.
The inliner throws the state-machine version away, duplicates
$$forInline version and then call state-machine generator.
If these suspend functions/lambdas are not going to be inlined,
$$forInline version is not generated. However, all objects, which are
used in these suspend functions/lambdas, have $$forInline version
written to OUTERCLASS field. This leads to errors by proguard.
Since they are used in both state-machine version and for-inline ones,
we can simply remove $$forInline suffix from OUTERCLASS field and this
fixes the issue.
#KT-31242 Fixed
In 1.3.31 I fixed Java interop for inline function with coroutines
(TL;DR: when we need a state machine, generate two methods: one with
normal name, and the other one with $$forInline suffix, for the inliner
to use, just like inline suspend functions), however, I forgot a case
with inline suspend function with inline suspend function parameter.
In this case, the compiler a generated two functions, as needed, but,
neither of them had a state-machine. This change adds the state-machine
for the method with normal name. Note, that suspend inline functions
with crossinline parameter, which are also supported by the change,
did not cause incorrect behaviour, since until now they were generated
as synthetic.
#KT-31354 Fixed
Denis Zharkov