svn commit: r1462662 - /incubator/vxquery/trunk/vxquery/vxquery-core/src/main/java/org/apache/vxquery/compiler/rewriter/rules/InlineReferenceVariablesRule.java

[pr...@apache.org]

Author: prestonc
Date: Fri Mar 29 22:34:22 2013
New Revision: 1462662

URL: http://svn.apache.org/r1462662
Log:
This rule is used after many of the XQuery specific rules to remove the null operations.

Added:
    incubator/vxquery/trunk/vxquery/vxquery-core/src/main/java/org/apache/vxquery/compiler/rewriter/rules/InlineReferenceVariablesRule.java   (with props)

Added: incubator/vxquery/trunk/vxquery/vxquery-core/src/main/java/org/apache/vxquery/compiler/rewriter/rules/InlineReferenceVariablesRule.java
URL: http://svn.apache.org/viewvc/incubator/vxquery/trunk/vxquery/vxquery-core/src/main/java/org/apache/vxquery/compiler/rewriter/rules/InlineReferenceVariablesRule.java?rev=1462662&view=auto
==============================================================================
--- incubator/vxquery/trunk/vxquery/vxquery-core/src/main/java/org/apache/vxquery/compiler/rewriter/rules/InlineReferenceVariablesRule.java (added)
+++ incubator/vxquery/trunk/vxquery/vxquery-core/src/main/java/org/apache/vxquery/compiler/rewriter/rules/InlineReferenceVariablesRule.java Fri Mar 29 22:34:22 2013
@@ -0,0 +1,99 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.vxquery.compiler.rewriter.rules;
+
+import java.util.List;
+
+import org.apache.commons.lang3.mutable.Mutable;
+
+import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalExpression;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalPlan;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.IOptimizationContext;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalExpressionTag;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalOperatorTag;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalVariable;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AssignOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.SubplanOperator;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.InlineVariablesRule;
+
+/**
+ * Where assign operators only assign a new variable ID for a reference expression,
+ * all references are updated to the first variable ID.
+ */
+public class InlineReferenceVariablesRule extends InlineVariablesRule {
+
+    @Override
+    protected boolean performBottomUpAction(AbstractLogicalOperator op) throws AlgebricksException {
+        inlineVisitor.setOperator(op);
+        return op.acceptExpressionTransform(inlineVisitor);
+    }
+
+    @Override
+    protected boolean inlineVariables(Mutable<ILogicalOperator> opRef, IOptimizationContext context)
+            throws AlgebricksException {
+        AbstractLogicalOperator op = (AbstractLogicalOperator) opRef.getValue();
+
+        // Update mapping from variables to expressions during top-down traversal.
+        if (op.getOperatorTag() == LogicalOperatorTag.ASSIGN) {
+            AssignOperator assignOp = (AssignOperator) op;
+            List<LogicalVariable> vars = assignOp.getVariables();
+            List<Mutable<ILogicalExpression>> exprs = assignOp.getExpressions();
+            for (int i = 0; i < vars.size(); i++) {
+                ILogicalExpression expr = exprs.get(i).getValue();
+                // Ignore functions.                
+                if (expr.getExpressionTag() == LogicalExpressionTag.FUNCTION_CALL) {
+                    continue;
+                }
+                varAssignRhs.put(vars.get(i), exprs.get(i).getValue());
+            }
+        }
+
+        boolean modified = false;
+        // Descend into nested plans removing projects on the way.
+        if (op.getOperatorTag() == LogicalOperatorTag.SUBPLAN) {
+            SubplanOperator subplan = (SubplanOperator) op;
+            for (ILogicalPlan nestedOpRef : subplan.getNestedPlans()) {
+                for (Mutable<ILogicalOperator> rootOpRef : nestedOpRef.getRoots()) {
+                    if (inlineVariables(rootOpRef, context)) {
+                        modified = true;
+                    }
+                }
+            }
+        }
+        // Descend into children removing projects on the way.
+        for (Mutable<ILogicalOperator> inputOpRef : op.getInputs()) {
+            if (inlineVariables(inputOpRef, context)) {
+                modified = true;
+            }
+        }
+
+        if (performBottomUpAction(op)) {
+            modified = true;
+        }
+
+        if (modified) {
+            context.computeAndSetTypeEnvironmentForOperator(op);
+            context.addToDontApplySet(this, op);
+            // Re-enable rules that we may have already tried. They could be applicable now after inlining.
+            context.removeFromAlreadyCompared(opRef.getValue());
+        }
+
+        return modified;
+    }
+
+}

Propchange: incubator/vxquery/trunk/vxquery/vxquery-core/src/main/java/org/apache/vxquery/compiler/rewriter/rules/InlineReferenceVariablesRule.java
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