Fixed a bug in the optimizer which was preventi...

Fixed a bug in the optimizer which was preventing private methods from
being inlined. Also relaxes a condition related to the "liftedTry"
problem: the inliner has to exclude certain methods from consideration
if there is a value on the stack and the method being inlined has
exception handlers. The new condition is as before, except that it does
not exclude methods of the "try/finally" variety (i.e. finalizers, but
no other exception handlers.) This is necessary to optimize this common
pattern:

  @inline private def foo(body: => Unit) {
    val saved = something
    try body
    finally something = saved
  }

The closure for "body" can be fully eliminated, but only if the contents
of foo can be inlined into the caller.

Closes #4764, review by rompf.

1 files changed, 8 insertions, 0 deletions

diff --git a/src/compiler/scala/tools/nsc/Global.scala b/src/compiler/scala/tools/nsc/Global.scala
index 2cf8246db1..d48b6fa569 100644
--- a/src/compiler/scala/tools/nsc/Global.scala
+++ b/src/compiler/scala/tools/nsc/Global.scala
@@ -163,6 +163,14 @@ class Global(var currentSettings: Settings, var reporter: Reporter) extends Symb
     if (opt.fatalWarnings) globalError(msg)
     else reporter.warning(NoPosition, msg)
 
+  @inline final def ifDebug(body: => Unit) {
+    if (settings.debug.value)
+      body
+  }
+  @inline final def debuglog(msg: => String) {
+    if (settings.debug.value)
+      inform("[log " + phase + "] " + msg)
+  }
   private def elapsedMessage(msg: String, start: Long) =
     msg + " in " + (currentTime - start) + "ms"