From 91dbfb2a8f466cf30f7b02cbc6f3e89376d31c59 Mon Sep 17 00:00:00 2001 From: Tiark Rompf Date: Tue, 29 Nov 2011 18:56:51 +0000 Subject: improve cps handling of if-then-else. no review. --- .../tools/selectivecps/SelectiveANFTransform.scala | 62 ++++++++++++---------- test/files/continuations-run/ifelse4.check | 4 ++ test/files/continuations-run/ifelse4.scala | 31 +++++++++++ test/files/continuations-run/patvirt.check | 2 + test/files/continuations-run/patvirt.scala | 32 +++++++++++ 5 files changed, 102 insertions(+), 29 deletions(-) create mode 100644 test/files/continuations-run/ifelse4.check create mode 100644 test/files/continuations-run/ifelse4.scala create mode 100644 test/files/continuations-run/patvirt.check create mode 100644 test/files/continuations-run/patvirt.scala diff --git a/src/continuations/plugin/scala/tools/selectivecps/SelectiveANFTransform.scala b/src/continuations/plugin/scala/tools/selectivecps/SelectiveANFTransform.scala index 9f1d3dfcd6..b383227243 100644 --- a/src/continuations/plugin/scala/tools/selectivecps/SelectiveANFTransform.scala +++ b/src/continuations/plugin/scala/tools/selectivecps/SelectiveANFTransform.scala @@ -173,40 +173,44 @@ abstract class SelectiveANFTransform extends PluginComponent with Transform with (Nil, tree1, cpsA) - case If(cond, thenp, elsep) => - - val (condStats, condVal, spc) = transInlineValue(cond, cpsA) - - val (cpsA2, cpsR2) = (spc, linearize(spc, getAnswerTypeAnn(tree.tpe))) -// val (cpsA2, cpsR2) = (None, getAnswerTypeAnn(tree.tpe)) - val thenVal = transExpr(thenp, cpsA2, cpsR2) - val elseVal = transExpr(elsep, cpsA2, cpsR2) - - // check that then and else parts agree (not necessary any more, but left as sanity check) - if (cpsR.isDefined) { - if (elsep == EmptyTree) - unit.error(tree.pos, "always need else part in cps code") - } - if (hasAnswerTypeAnn(thenVal.tpe) != hasAnswerTypeAnn(elseVal.tpe)) { - unit.error(tree.pos, "then and else parts must both be cps code or neither of them") - } + case If(cond, thenp, elsep) => + /* possible situations: + cps before (cpsA) + cps in condition (spc) <-- synth flag set if *only* here! + cps in (one or both) branches */ + val (condStats, condVal, spc) = transInlineValue(cond, cpsA) + val (cpsA2, cpsR2) = if (hasSynthMarker(tree.tpe)) + (spc, linearize(spc, getAnswerTypeAnn(tree.tpe))) else + (None, getAnswerTypeAnn(tree.tpe)) // if no cps in condition, branches must conform to tree.tpe directly + val thenVal = transExpr(thenp, cpsA2, cpsR2) + val elseVal = transExpr(elsep, cpsA2, cpsR2) + + // check that then and else parts agree (not necessary any more, but left as sanity check) + if (cpsR.isDefined) { + if (elsep == EmptyTree) + unit.error(tree.pos, "always need else part in cps code") + } + if (hasAnswerTypeAnn(thenVal.tpe) != hasAnswerTypeAnn(elseVal.tpe)) { + unit.error(tree.pos, "then and else parts must both be cps code or neither of them") + } - (condStats, updateSynthFlag(treeCopy.If(tree, condVal, thenVal, elseVal)), spc) + (condStats, updateSynthFlag(treeCopy.If(tree, condVal, thenVal, elseVal)), spc) - case Match(selector, cases) => + case Match(selector, cases) => - val (selStats, selVal, spc) = transInlineValue(selector, cpsA) - val (cpsA2, cpsR2) = (spc, linearize(spc, getAnswerTypeAnn(tree.tpe))) -// val (cpsA2, cpsR2) = (None, getAnswerTypeAnn(tree.tpe)) + val (selStats, selVal, spc) = transInlineValue(selector, cpsA) + val (cpsA2, cpsR2) = if (hasSynthMarker(tree.tpe)) + (spc, linearize(spc, getAnswerTypeAnn(tree.tpe))) else + (None, getAnswerTypeAnn(tree.tpe)) - val caseVals = for { - cd @ CaseDef(pat, guard, body) <- cases - bodyVal = transExpr(body, cpsA2, cpsR2) - } yield { - treeCopy.CaseDef(cd, transform(pat), transform(guard), bodyVal) - } + val caseVals = for { + cd @ CaseDef(pat, guard, body) <- cases + bodyVal = transExpr(body, cpsA2, cpsR2) + } yield { + treeCopy.CaseDef(cd, transform(pat), transform(guard), bodyVal) + } - (selStats, updateSynthFlag(treeCopy.Match(tree, selVal, caseVals)), spc) + (selStats, updateSynthFlag(treeCopy.Match(tree, selVal, caseVals)), spc) case ldef @ LabelDef(name, params, rhs) => diff --git a/test/files/continuations-run/ifelse4.check b/test/files/continuations-run/ifelse4.check new file mode 100644 index 0000000000..2545dd49a0 --- /dev/null +++ b/test/files/continuations-run/ifelse4.check @@ -0,0 +1,4 @@ +10 +10 +10 +10 diff --git a/test/files/continuations-run/ifelse4.scala b/test/files/continuations-run/ifelse4.scala new file mode 100644 index 0000000000..8360375283 --- /dev/null +++ b/test/files/continuations-run/ifelse4.scala @@ -0,0 +1,31 @@ +import scala.util.continuations._ + +object Test { + def sh(x1:Int) = shift( (k: Int => Int) => k(k(k(x1)))) + + def testA(x1: Int): Int @cps[Int] = { + sh(x1) + if (x1==42) x1 else sh(x1) + } + + def testB(x1: Int): Int @cps[Int] = { + if (sh(x1)==43) x1 else x1 + } + + def testC(x1: Int): Int @cps[Int] = { + sh(x1) + if (sh(x1)==44) x1 else x1 + } + + def testD(x1: Int): Int @cps[Int] = { + sh(x1) + if (sh(x1)==45) x1 else sh(x1) + } + + def main(args: Array[String]): Any = { + println(reset(1 + testA(7))) + println(reset(1 + testB(9))) + println(reset(1 + testC(9))) + println(reset(1 + testD(7))) + } +} \ No newline at end of file diff --git a/test/files/continuations-run/patvirt.check b/test/files/continuations-run/patvirt.check new file mode 100644 index 0000000000..b5fa014ad3 --- /dev/null +++ b/test/files/continuations-run/patvirt.check @@ -0,0 +1,2 @@ +10 +11 diff --git a/test/files/continuations-run/patvirt.scala b/test/files/continuations-run/patvirt.scala new file mode 100644 index 0000000000..5b4d312f20 --- /dev/null +++ b/test/files/continuations-run/patvirt.scala @@ -0,0 +1,32 @@ +import scala.util.continuations._ + +object Test { + def sh(x1:Int) = shift( (k: Int => Int) => k(k(k(x1)))) + + def test(x1: Int) = { + val o7 = { + val o6 = { + val o3 = + if (7 == x1) Some(x1) + else None + + if (o3.isEmpty) None + else Some(sh(x1)) + } + if (o6.isEmpty) { + val o5 = + if (8 == x1) Some(x1) + else None + + if (o5.isEmpty) None + else Some(sh(x1)) + } else o6 + } + o7.get + } + + def main(args: Array[String]): Any = { + println(reset(1 + test(7))) + println(reset(1 + test(8))) + } +} -- cgit v1.2.3