# HG changeset patch
# User Miguel Garcia <miguel.m.garcia@oracle.com>
# Date 1401471696 -7200
# Node ID 03b1d8f6b4ef7053310808236e865bc7c6342cb2
# Parent  23e6edbe4c763bd16ff80510fb2268476e0add29
[inlining] preparations to avoid cloning whenever possible

diff -r 23e6edbe4c76 -r 03b1d8f6b4ef graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/inlining/info/elem/InlineableGraph.java
--- a/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/inlining/info/elem/InlineableGraph.java	Fri May 30 19:00:27 2014 +0200
+++ b/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/inlining/info/elem/InlineableGraph.java	Fri May 30 19:41:36 2014 +0200
@@ -73,27 +73,9 @@
 
         try (Debug.Scope s = Debug.scope("InlineGraph", newGraph)) {
 
-            boolean callerHasMoreInformationAboutArguments = false;
-            NodeInputList<ValueNode> args = invoke.callTarget().arguments();
-            ArrayList<Node> parameterUsages = new ArrayList<>();
-            for (ParameterNode param : newGraph.getNodes(ParameterNode.class).snapshot()) {
-                ValueNode arg = args.get(param.index());
-                if (arg.isConstant()) {
-                    Constant constant = arg.asConstant();
-                    newGraph.replaceFloating(param, ConstantNode.forConstant(constant, context.getMetaAccess(), newGraph));
-                    callerHasMoreInformationAboutArguments = true;
-                    param.usages().snapshotTo(parameterUsages);
-                } else {
-                    Stamp joinedStamp = param.stamp().join(arg.stamp());
-                    if (joinedStamp != null && !joinedStamp.equals(param.stamp())) {
-                        param.setStamp(joinedStamp);
-                        callerHasMoreInformationAboutArguments = true;
-                        param.usages().snapshotTo(parameterUsages);
-                    }
-                }
-            }
-
-            if (callerHasMoreInformationAboutArguments) {
+            if (existProfitableParamArgReplacements(invoke, newGraph)) {
+                ArrayList<Node> parameterUsages = replaceParamsWithMoreInformativeArguments(invoke, newGraph, context);
+                assert !parameterUsages.isEmpty() : "The caller didn't have more information about arguments after all";
                 if (OptCanonicalizer.getValue()) {
                     canonicalizer.applyIncremental(newGraph, context, parameterUsages);
                 }
@@ -109,6 +91,60 @@
         }
     }
 
+    private static boolean existProfitableParamArgReplacements(final Invoke invoke, final StructuredGraph newGraph) {
+        NodeInputList<ValueNode> args = invoke.callTarget().arguments();
+        for (ParameterNode param : newGraph.getNodes(ParameterNode.class)) {
+            if (param.usages().isNotEmpty()) {
+                ValueNode arg = args.get(param.index());
+                if (isArgMoreInformativeThanParam(arg, param)) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
+    private static boolean isArgMoreInformativeThanParam(ValueNode arg, ParameterNode param) {
+        if (arg.isConstant()) {
+            return true;
+        } else {
+            Stamp joinedStamp = param.stamp().join(arg.stamp());
+            if (joinedStamp != null && !joinedStamp.equals(param.stamp())) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * This method must adopt the same definition of "more informative argument" as used in
+     * {@link #existProfitableParamArgReplacements(Invoke, StructuredGraph)}
+     */
+    private static ArrayList<Node> replaceParamsWithMoreInformativeArguments(final Invoke invoke, final StructuredGraph newGraph, final HighTierContext context) {
+        NodeInputList<ValueNode> args = invoke.callTarget().arguments();
+        ArrayList<Node> parameterUsages = new ArrayList<>();
+        for (ParameterNode param : newGraph.getNodes(ParameterNode.class).snapshot()) {
+            if (param.usages().isNotEmpty()) {
+                ValueNode arg = args.get(param.index());
+                if (arg.isConstant()) {
+                    Constant constant = arg.asConstant();
+                    param.usages().snapshotTo(parameterUsages);
+                    // collect param usages before replacing the param
+                    newGraph.replaceFloating(param, ConstantNode.forConstant(constant, context.getMetaAccess(), newGraph));
+                } else {
+                    Stamp joinedStamp = param.stamp().join(arg.stamp());
+                    if (joinedStamp != null && !joinedStamp.equals(param.stamp())) {
+                        param.setStamp(joinedStamp);
+                        param.usages().snapshotTo(parameterUsages);
+                    } else {
+                        assert !isArgMoreInformativeThanParam(arg, param);
+                    }
+                }
+            }
+        }
+        return parameterUsages;
+    }
+
     private static StructuredGraph getCachedGraph(ResolvedJavaMethod method, HighTierContext context) {
         if (context.getGraphCache() != null) {
             StructuredGraph cachedGraph = context.getGraphCache().get(method);