Collect call site information and use that for estimating parameter types

lib/compiler/implementation/ssa/builder.dart

Index: lib/compiler/implementation/ssa/builder.dart
diff --git a/lib/compiler/implementation/ssa/builder.dart b/lib/compiler/implementation/ssa/builder.dart
index a66dbaf7c2a4c7ff9fa48ead04383232ebeafb22..c006fc54afb5783870867adb8eb67ede99a1c4cf 100644
--- a/lib/compiler/implementation/ssa/builder.dart
+++ b/lib/compiler/implementation/ssa/builder.dart
@@ -138,6 +138,7 @@ class SsaBuilderTask extends CompilerTask {
   // Loop tracking information.
   final Set<FunctionElement> functionsCalledInLoop;
   final Map<SourceString, Selector> selectorsCalledInLoop;
+  final JavaScriptBackend backend;
 
   String get name() => 'SSA builder';
 
@@ -147,6 +148,7 @@ class SsaBuilderTask extends CompilerTask {
       emitter = backend.emitter,
       functionsCalledInLoop = new Set<FunctionElement>(),
       selectorsCalledInLoop = new Map<SourceString, Selector>(),
+      backend = backend,
       super(backend.compiler);
 
   HGraph build(WorkItem work) {
@@ -171,6 +173,18 @@ class SsaBuilderTask extends CompilerTask {
         inLoop = selector !== null && selector.applies(element, compiler);
       }
       graph.calledInLoop = inLoop;
+
+      // If there is an estimate of the parameter types assume these types when

[floitsch, 2012/08/06 15:01:06]

Optimistically use the parameter types that have been seen so far. The method
will be recompiled if the assumptions fail.

[Søren Gjesse, 2012/08/07 09:06:03]

Much better, thanks.

+      // compiling.
+      List<HType> parameterTypes = backend.optimisticParameterTypes(element);
+      if (parameterTypes != null) {
+        FunctionSignature signature = element.computeSignature(compiler);
+        int i = 0;
+        signature.forEachParameter((Element param) {
+          builder.parameters[param].guaranteedType = parameterTypes[i++];
+        });
+      }
+
       if (compiler.tracer.enabled) {
         String name;
         if (element.enclosingElement !== null &&