Fix: temporary shareable should not be 'value' of explicit RPromise

com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/function/PromiseHelperNode.java

@@ -50,6 +50,7 @@ import com.oracle.truffle.r.runtime.data.RPromise;
 import com.oracle.truffle.r.runtime.data.RPromise.EagerPromise;
 import com.oracle.truffle.r.runtime.data.RPromise.EagerPromiseBase;
 import com.oracle.truffle.r.runtime.data.RPromise.PromiseState;
+import com.oracle.truffle.r.runtime.data.RShareable;
 import com.oracle.truffle.r.runtime.nodes.RBaseNode;
 
 /**
@@ -237,6 +238,16 @@ public class PromiseHelperNode extends RBaseNode {
                     return promise.getValue();
                 }
                 Object obj = generateValueDefaultSlowPath(frame, promise);
+                // if the value is temporary, we increment the reference count. The reason is that
+                // temporary values are considered available to be reused and altered (e.g. as a
+                // result of arithmetic operation), which is what we do not want to happen to a
+                // value that we are saving as the promise result.
+                if (obj instanceof RShareable) {
+                    RShareable shareable = (RShareable) obj;
+                    if (shareable.isTemporary()) {
+                        shareable.incRefCount();
+                    }
+                }
                 promise.setValue(obj);
                 return obj;
             }

com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test

@@ -77177,6 +77177,10 @@ Error in get("x") : object 'x' not found
 #{ x <- function(){3} ; gg <- function() { assign("x", 4) ; g <- function() { if (FALSE) { x <- 2 } ; f <- function() { h <- function() { x() } ; h() } ; f() } ; g() } ; gg() }
 [1] 3
+##com.oracle.truffle.r.test.library.base.TestPromiseOptimizations.testDeoptimization#
+#{ delayedAssign('x', c(1,2,3)); x/180; x }
+[1] 1 2 3
+
 ##com.oracle.truffle.r.test.library.base.TestPromiseOptimizations.testDeoptimization#
 #{ f <- function(x) { assign('e', function() {x}, parent.frame()) } ; a <- 1 ; f( a ) ; a <- 10 ; e() }
 [1] 10
@@ -77217,6 +77221,10 @@ Error in get("x") : object 'x' not found
 #{ f <- function(x) { sys.frame(sys.nframe()) } ; a <- 1 ; e <- f( a ) ; a <- 10 ; e$x }
 [1] 10
+##com.oracle.truffle.r.test.library.base.TestPromiseOptimizations.testDeoptimization#
+#{ pi/180; pi }
+[1] 3.141593
+
 ##com.oracle.truffle.r.test.library.base.TestSimpleArithmetic.testArithmeticUpdate#
 #{ x <- 3 ; f <- function(z) { if (z) { x <- 1 } ; x <- 1L + x ; x } ; f(FALSE) }
 [1] 4

com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/library/base/TestPromiseOptimizations.java

 /*
- * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -61,5 +61,11 @@ public class TestPromiseOptimizations extends TestBase {
 
         // "delayedAssign" RFunction: (Special case of but handled by: delayedAssign)
         assertEval("{ f <- function(x) { delayedAssign('b', function() {x}, sys.frame(sys.nframe()), parent.frame()); } ; a <- 1 ; f( a ) ; a <- 10 ; b() }");
+
+        // the value of 'pi' promise may look like temporary vector, but the arithmetic operation
+        // must not re-use it for the result
+        assertEval("{ pi/180; pi }");
+        // similar situation as above
+        assertEval("{ delayedAssign('x', c(1,2,3)); x/180; x }");
     }
 }