* In blocks, discard the result of any statement that has a return
type other than void. This was previously done by wrapping each
statement into an "implicit Unit conversion" that was actually
compiled down to a stack pop instead. If an expression happened to
already have type Unit, however, such a conversion was not inserted,
resulting in a stray reference on the stack. These conversions are
now redundant and should probably be removed.
* In assignments and non-exhaustive conditionals, materialize a Unit
on the stack to avoid depth mismatches that trip up the bytecode
validator. Because such expressions are generally used at block level
(and, indeed, the frontend will reject a non-exhaustive conditional
used as an expression), combined with the above change this results
in no additional GETSTATIC opcodes, as they are immediately removed
by the peephole optimizer.
Specifically, defer the removal of hand-written "if (true|false)" from
JvmBuiltinOptimizationLowering into codegen so that appropriate debug
info (and a NOP) can be inserted.
Change-Id: Ia11af05ad8b4251946bd3e685fb7c3319f0f433f
Simplify ifs when branches have condition true/false.
Simplify blocks containing only a variable declaration
and a variable get of the same variable. Simplify to
just the condition.
Do not introduce temporary variables for constants for
null checks. Constants have no side-effects and can be
reloaded freely instead of going through a local.
This simplifies code such as "42.toLong()!!" so that the
resulting code has no branches and uses no locals. The
simplifications happen as follows:
```
block
temp = 42.toLong()
when
(temp == null) throw NPE
(true) load temp
---> null test simplification
block
temp = 42.toLong()
when
(false) throw NPE
(true) load temp
---> when simplification
block
temp = 42.toLong()
load temp
---> block simplification
42.toLong()
```
Most of these tests used this directive as a way to opt in to a new
language feature, and most of those features are already stable for a
long time, so no opt-in is needed. Some other tests used the directive
to opt out from a language feature, replace those by the `LANGUAGE`
directive. One test used the directive to test behavior that actually
depended on the API version; use `API_VERSION` directive there instead.
[JS IR BE] Runtime fixes
* Do not generate external declarations for IR BE
* Move `arrayToString` helper function out of shared JS stdlib
* Fix arrays type check for IR BE
* Move FinallyBlockLowering to common part
* Fix catching of dynamic exception
* Fix bridges for suspend functions
* Disable explicit cast to Unit
* Run lowering per module
* Update some test data
- Into PrimitiveNumberRangeLiteralRangeValue modifies how bounded
value are created by checking if the high bound range can be modified
to be exclusive instead of inclusive such as the generated code will
be optimized.
- Add black box tests checking that the specialization does not fail
on any kind of arrays.
- Add a bytecode test checking that the code is correctly optimized.
Fix of https://youtrack.jetbrains.com/issue/KT-22334
