Some deadcode optimizations on JMultiExpressions to remove side-effect free expressions. Includes an optimization for field references whose only side-effect is a clinit. This is in anticipation of a change to remove unused parameters.
Patch by: mmastrac
Review by: scottb
git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@1479 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/dev/core/src/com/google/gwt/dev/jjs/impl/DeadCodeElimination.java b/dev/core/src/com/google/gwt/dev/jjs/impl/DeadCodeElimination.java
index d103fd7..ded8056 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/impl/DeadCodeElimination.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/impl/DeadCodeElimination.java
@@ -28,6 +28,7 @@
import com.google.gwt.dev.jjs.ast.JDoubleLiteral;
import com.google.gwt.dev.jjs.ast.JExpression;
import com.google.gwt.dev.jjs.ast.JExpressionStatement;
+import com.google.gwt.dev.jjs.ast.JFieldRef;
import com.google.gwt.dev.jjs.ast.JForStatement;
import com.google.gwt.dev.jjs.ast.JIfStatement;
import com.google.gwt.dev.jjs.ast.JIntLiteral;
@@ -47,6 +48,7 @@
import com.google.gwt.dev.jjs.ast.JValueLiteral;
import com.google.gwt.dev.jjs.ast.JVisitor;
import com.google.gwt.dev.jjs.ast.JWhileStatement;
+import com.google.gwt.dev.jjs.ast.js.JMultiExpression;
import java.lang.reflect.Method;
import java.util.ArrayList;
@@ -286,6 +288,41 @@
}
/**
+ * Remove any parts of JMultiExpression that have no side-effect.
+ */
+ @Override
+ public void endVisit(JMultiExpression x, Context ctx) {
+ for (int i = 0; i < x.exprs.size() - 1; i++) {
+ JExpression expr = x.exprs.get(i);
+ if (!expr.hasSideEffects()) {
+ x.exprs.remove(i);
+ i--;
+ continue;
+ }
+
+ if (expr instanceof JFieldRef) {
+ JFieldRef fieldRef = (JFieldRef) expr;
+ JExpression instance = fieldRef.getInstance();
+ if (instance == null || !instance.hasSideEffects()) {
+ // If the instance doesn't have side-effects, but the field ref
+ // does, it's because a clinit() needs to happen.
+ JMethod clinit = fieldRef.getField().getEnclosingType().methods.get(0);
+ assert (clinit.getName().equals("$clinit"));
+
+ // Replace the field ref with a direct call to the clinit.
+ JMethodCall methodCall = new JMethodCall(program,
+ expr.getSourceInfo(), instance, clinit);
+ x.exprs.set(i, methodCall);
+ }
+ }
+ }
+
+ if (x.exprs.size() == 1) {
+ ctx.replaceMe(x.exprs.get(0));
+ }
+ }
+
+ /**
* Simplify the ! operator if possible.
*/
@Override
diff --git a/dev/core/src/com/google/gwt/dev/jjs/impl/MethodInliner.java b/dev/core/src/com/google/gwt/dev/jjs/impl/MethodInliner.java
index a395f83..cb2b7dd 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/impl/MethodInliner.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/impl/MethodInliner.java
@@ -110,11 +110,17 @@
public void endVisit(JMethodCall x, Context ctx) {
JMethod method = x.getTarget();
- // The method call must be known statically
+ // The method call must be known statically.
if (!method.isStatic() || method.isNative()) {
return;
}
+ // The target must not be a clinit method.
+ if (method.getEnclosingType() != null
+ && method.getEnclosingType().methods.get(0) == method) {
+ return;
+ }
+
if (cannotInline.contains(method)) {
return;
}
diff --git a/dev/core/src/com/google/gwt/dev/jjs/impl/Pruner.java b/dev/core/src/com/google/gwt/dev/jjs/impl/Pruner.java
index 53ff0de..aa37346 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/impl/Pruner.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/impl/Pruner.java
@@ -15,6 +15,7 @@
*/
package com.google.gwt.dev.jjs.impl;
+import com.google.gwt.dev.jjs.ast.CanBeStatic;
import com.google.gwt.dev.jjs.ast.Context;
import com.google.gwt.dev.jjs.ast.JAbsentArrayDimension;
import com.google.gwt.dev.jjs.ast.JArrayType;
@@ -225,13 +226,9 @@
return false;
}
- private boolean pruneViaNoninstantiability(boolean isInstantiated, JField it) {
- return (!isInstantiated && !it.isStatic());
- }
-
private boolean pruneViaNoninstantiability(boolean isInstantiated,
- JMethod it) {
- return (!isInstantiated && (!it.isStatic() || program.isStaticImpl(it)));
+ CanBeStatic it) {
+ return (!isInstantiated && !it.isStatic());
}
}
