RFR (S): use invoker's stamp if target's return stamp is of different type

[Thomas Wuerthinger]

Looks good - please push!

- thomas

On May 17, 2013, at 1:00 AM, Christian Thalinger <christian.thalinger at oracle.com> wrote:

> This is a fix for 292.
> 
> -- Chris
> 
> diff --git a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/replacements/AbstractMethodHandleNode.java b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/replacements/AbstractMethodHandleNode.java
> --- a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/replacements/AbstractMethodHandleNode.java
> +++ b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/replacements/AbstractMethodHandleNode.java
> @@ -273,9 +273,20 @@
>             ValueNode[] args = replacementArguments.toArray(new ValueNode[replacementArguments.size()]);
>             callTarget = new SelfReplacingMethodCallTargetNode(invokeKind, targetMethod, targetArguments, returnType, replacementTargetMethod, args, replacementReturnType);
>         }
> +        graph().add(callTarget);
> 
> -        graph().add(callTarget);
> -        InvokeNode invoke = graph().add(new InvokeNode(callTarget, getBci()));
> +        // The call target can have a different return type than the invoker,
> +        // e.g. the target returns an Object but the invoker void. In this case
> +        // we need to use the stamp of the invoker. Note: always using the
> +        // invoker's stamp would be wrong because it's a less concrete type
> +        // (usually java.lang.Object).
> +        InvokeNode invoke;
> +        if (callTarget.returnStamp().kind() != stamp().kind()) {
> +            invoke = new InvokeNode(callTarget, getBci(), stamp());
> +        } else {
> +            invoke = new InvokeNode(callTarget, getBci());
> +        }
> +        graph().add(invoke);
>         invoke.setStateAfter(stateAfter());
>         return invoke;
>     }
> diff --git a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/InvokeNode.java b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/InvokeNode.java
> --- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/InvokeNode.java
> +++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/InvokeNode.java
> @@ -29,6 +29,7 @@
> import com.oracle.graal.nodes.extended.*;
> import com.oracle.graal.nodes.extended.LocationNode.LocationIdentity;
> import com.oracle.graal.nodes.spi.*;
> +import com.oracle.graal.nodes.type.Stamp;
> import com.oracle.graal.nodes.util.*;
> 
> /**
> @@ -47,11 +48,22 @@
>     /**
>      * Constructs a new Invoke instruction.
>      * 
> +     * @param callTarget the target method being called
>      * @param bci the bytecode index of the original invoke (used for debug infos)
> -     * @param callTarget the target method being called
>      */
>     public InvokeNode(CallTargetNode callTarget, int bci) {
> -        super(callTarget.returnStamp());
> +        this(callTarget, bci, callTarget.returnStamp());
> +    }
> +
> +    /**
> +     * Constructs a new Invoke instruction.
> +     * 
> +     * @param callTarget the target method being called
> +     * @param bci the bytecode index of the original invoke (used for debug infos)
> +     * @param stamp the stamp to be used for this value
> +     */
> +    public InvokeNode(CallTargetNode callTarget, int bci, Stamp stamp) {
> +        super(stamp);
>         this.callTarget = callTarget;
>         this.bci = bci;
>         this.polymorphic = false;
>