- changed pattern matcher to use the erased ver...

- changed pattern matcher to use the erased versions of asInstanceOf
when possible, to gain some speed when run time types are enabled; i.e.
instead of generating code like this:

    if (x.isInstanceOf[List[Int]]) {
      val temp$ = x.asInstanceOf[List[Int]];
      ...
    }

  the pattern matcher now generates code like that:

    if (x.isInstanceOf[List[Int]]) {
      val temp$ = x.asInstanceOf$erased[List[Int]];
      ...
    }

2 files changed, 17 insertions, 11 deletions

diff --git a/sources/scala/tools/scalac/transformer/matching/PatternMatcher.scala b/sources/scala/tools/scalac/transformer/matching/PatternMatcher.scala
index f731648124..7249cc4360 100644
--- a/sources/scala/tools/scalac/transformer/matching/PatternMatcher.scala
+++ b/sources/scala/tools/scalac/transformer/matching/PatternMatcher.scala
@@ -897,7 +897,7 @@ class PatternMatcher(unit: CompilationUnit) extends PatternTool(unit) {
           case ConstrPat(casted) =>
             return gen.If(gen.mkIsInstanceOf(selector.duplicate(), node.getTpe()),
                           gen.mkBlock(gen.ValDef(casted,
-                                                 gen.mkAsInstanceOf(selector.duplicate(), node.getTpe())),
+                                                 gen.mkAsInstanceOf(selector.pos, selector.duplicate(), node.getTpe(), true)),
                                       toTree(node.and)),
                           toTree(node.or, selector.duplicate()));
           case SequencePat(casted, len) =>
@@ -905,11 +905,11 @@ class PatternMatcher(unit: CompilationUnit) extends PatternTool(unit) {
           cf.Or(
             cf.And(
               cf.And(gen.mkIsInstanceOf(selector.duplicate(), node.getTpe()),
-                     cf.Equals(gen.mkApply__(gen.Select(gen.mkAsInstanceOf(selector.duplicate(), node.getTpe()),
+                     cf.Equals(gen.mkApply__(gen.Select(gen.mkAsInstanceOf(selector.pos, selector.duplicate(), node.getTpe(), true),
                                                         defs.SEQ_LENGTH())),
                                gen.mkIntLit(selector.pos, len))),
               gen.mkBlock(gen.ValDef(casted,
-                                     gen.mkAsInstanceOf(selector.duplicate(), node.getTpe())),
+                                     gen.mkAsInstanceOf(selector.pos, selector.duplicate(), node.getTpe(), true)),
                           toTree(node.and))),
             toTree(node.or, selector.duplicate()));
           case ConstantPat(value) =>
diff --git a/sources/scalac/ast/TreeGen.java b/sources/scalac/ast/TreeGen.java
index 43d1fc1ed5..9167a4cf94 100644
--- a/sources/scalac/ast/TreeGen.java
+++ b/sources/scalac/ast/TreeGen.java
@@ -640,23 +640,29 @@ public class TreeGen implements Kinds, Modifiers, TypeTags {
     }
 
     /** Builds an instance test with given value and type. */
-    public Tree mkIsInstanceOf(int pos, Tree value, Type type) {
-        Symbol sym = global.currentPhase.id >= global.PHASE.TYPESASVALUES.id()
-            ? definitions.ANY_IS_ERASED
-            : definitions.ANY_IS;
+    public Tree mkIsInstanceOf(int pos, Tree value, Type type, boolean erased) {
+        Symbol sym = erased ? definitions.ANY_IS_ERASED : definitions.ANY_IS;
         return mkApplyT_(pos, Select(value, sym), new Type[]{type});
     }
+    public Tree mkIsInstanceOf(int pos, Tree value, Type type) {
+        boolean afterTAV =
+            global.currentPhase.id >= global.PHASE.TYPESASVALUES.id();
+        return mkIsInstanceOf(pos, value, type, afterTAV);
+    }
     public Tree mkIsInstanceOf(Tree value, Type type) {
         return mkIsInstanceOf(value.pos, value, type);
     }
 
     /** Builds a cast with given value and type. */
-    public Tree mkAsInstanceOf(int pos, Tree value, Type type) {
-        Symbol sym = global.currentPhase.id >= global.PHASE.TYPESASVALUES.id()
-            ? definitions.ANY_AS_ERASED
-            : definitions.ANY_AS;
+    public Tree mkAsInstanceOf(int pos, Tree value, Type type, boolean erased) {
+        Symbol sym = erased ? definitions.ANY_AS_ERASED : definitions.ANY_AS;
         return mkApplyT_(pos, Select(value, sym), new Type[]{type});
     }
+    public Tree mkAsInstanceOf(int pos, Tree value, Type type) {
+        boolean afterTAV =
+            global.currentPhase.id >= global.PHASE.TYPESASVALUES.id();
+        return mkAsInstanceOf(pos, value, type, afterTAV);
+    }
     public Tree mkAsInstanceOf(Tree value, Type type) {
         return mkAsInstanceOf(value.pos, value, type);
     }