Fix #5386: Generate a synthetic val def and then apply the unary operator #5387
Conversation
compiler/src/dotty/tools/dotc/transform/InterceptedMethods.scala
Outdated
Show resolved
Hide resolved
compiler/src/dotty/tools/dotc/transform/InterceptedMethods.scala
Outdated
Show resolved
Hide resolved
compiler/src/dotty/tools/dotc/transform/InterceptedMethods.scala
Outdated
Show resolved
Hide resolved
compiler/src/dotty/tools/dotc/transform/InterceptedMethods.scala
Outdated
Show resolved
Hide resolved
|
@allanrenucci good question. What would be a recommended compiler phase? |
I don't know that's why I am raising the question. Hopefully someone more knowledgeable will see the question 😄 |
biboudis
dismissed
allanrenucci’s stale review
All suggestions where incorporated.
| @@ -22,6 +23,7 @@ object InterceptedMethods { | |||
| * - `x.##` for ## in Any becomes calls to ScalaRunTime.hash, | |||
| * using the most precise overload available | |||
| * - `x.getClass` for getClass in primitives becomes `x.getClass` with getClass in class Object. | |||
| * - `!{...;true}` becomes val tmp = {...;true};!tmp (similar to other primitives/unary ops) | |||
There was a problem hiding this comment.
What other primitives ? Where is that defined ?
There was a problem hiding this comment.
I should have written literal constants instead of primitives.
| @@ -45,6 +47,16 @@ class InterceptedMethods extends MiniPhase { | |||
| ctx.log(s"$phaseName rewrote $tree to $rewritten") | |||
| rewritten | |||
| } | |||
| // if the qualifier is constant folded then its type doesn't have a symbol | |||
There was a problem hiding this comment.
but if its type doesn't have a symbol, does that always mean that the qualifier is constant-folded ?
There was a problem hiding this comment.
The qualifier is not constant folded due to the side effectful println.
| @@ -45,6 +47,16 @@ class InterceptedMethods extends MiniPhase { | |||
| ctx.log(s"$phaseName rewrote $tree to $rewritten") | |||
| rewritten | |||
| } | |||
| // if the qualifier is constant folded then its type doesn't have a symbol | |||
| // in case a unary operator is applied to a block (potentially containing impure expressions) | |||
| // we create a synthetic variable and then apply the operator | |||
There was a problem hiding this comment.
What is special about unary operators here compared to any other method call on a block ?
There was a problem hiding this comment.
Would you mean something like that?
{
println("!")
1
}+2
There was a problem hiding this comment.
It feels like this should have a more general solution, independent of the fact that these are operators. I.e. in general:
{ ... }.m where m has constant type v --> { ...; v }
nicolasstucki
dismissed
their stale review
We should constant fold those cases
|
See #5479 for an another fix. |
|
Solved by #5479. |
I added the logic that lifts a block with a side-effectful operation at the
InterceptedMethodsphase. Is this the most appropriate place for that?What happens is essentially:
is rewritten to ->