Also deleted StepHandler. Since the HeaderInfo.needLastCalculation is
only set to true for handling step progressions, deleted that property
and all associated logic around it.
* 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.
Effectively, the following when structure:
when (s) {
s1, s2 -> e1,
s3 -> e2,
s4 -> e3,
...
else -> e
}
is implemented as:
when (s.hashCode()) {
h1 -> {
if (s == s1)
e1
else if (s == s2)
e1
else if (s == s3)
e2
else
e
}
h2 -> if (s == s3) e2 else e,
...
else -> e
}
where s1.hashCode() == s2.hashCode() == s3.hashCode() == h1,
s4.hashCode() == h2.
A tableswitch or lookupswitch is used for the hash code lookup.
Change-Id: I087bf623dbb4a41d3cc64399a1b42342a50757a6
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
A lookupswitch or tableswitch can be used if all conditions are equality
checks to constants. To be more specific, it can be done if:
1. All conditions are CALL 'EQEQ(Any?, Any?)': Boolean
2. All types of variables involved in comparison are in the same group
of Char/Byte/Short/Int, String or enum.
3. All arg0 refer to the same value.
4. All arg1 are IrConst<*>.
Change-Id: Ifd7cb618395f6c5cc64601018b446f0bb7f5891c
Consolidating these into IrStringConcatenations allows the backend to produce efficient code for string concatenations (e.g., using StringBuilder for JVM).
Introduce MetadataSource as a way to store the original descriptor for
any element (before any lowerings) and maintain it until the end of the
codegen where it's used in generating the metadata. Note that JVM
signatures written to the metadata are formed from the _resulting_
generated elements, not by mapping the original descriptors.
Some corner cases are not supported yet, namely properties declared in
companion objects, synthetic methods for property annotations,
JvmPackageName, etc.
#KT-29119 Fixed
For comparison intrinsics and for instanceof checks, make
it possible to get the the stack value produced and branch
on that directly instead of materializing a boolean to
branch on from it.
That reduces code such as
```
IF_CMPEQ L1
CONST_0
GOTO L2
L1: CONST_1
L2: IFEQ L3
```
to just one IF_CMP instruction.
The generated code is more inline with java, and we avoid the error of
accessing package-private field outside of the package.
However, this changes semantics a bit. Now, a user should set assertion
status of inline-site's package, instead of inline function's one.
#KT-28317: Fixed
Split the ConstAndJvmFieldPropertiesLowering into two: ConstLowering
which replaces const vals with their values, and
PropertiesToFieldsLowering which removes unnecessary property accessors
(such as for JvmField or private properties with default accessors) and
replaces calls to those accessors with field access
Initializers are "set field" expressions and are considered redundant
when they are:
1. In the primary constructor; and
2. Set the field to `0`, `false`, or `null`; and
3. Have a `null` origin. I.e., not in an initializer block or
constructor body, and therefore the field could not have been set by a
prior expression.
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()
```
Introduce lowering to remove null checks for primitive type
expressions and replace them with true/false. Side-effects
are preserved.
Generate ifnull/ifnonnull instructions for null checks instead
of materializing a null literal for an equality check.
Introduce lowering phase that turns !!exp -> exp for the boolean
'not' builtin. This makes sure that code such as
```
if (!!!!!booleanValue) {
doStuff()
}
```
generates only one branch.
All bytecode text tests are run with stdlib in the classpath and only
for JVM backend, therefore directives WITH_RUNTIME, TARGET_BACKEND,
IGNORE_BACKEND are not needed
