Adds patch to JsStaticEval to simplify literal1 + literal2 operations. (where literal can be one of: null, boolean, number, string)
Patch by: cromwellian
Review by: bobv
git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@6569 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/dev/core/src/com/google/gwt/dev/js/JsStaticEval.java b/dev/core/src/com/google/gwt/dev/js/JsStaticEval.java
index 113c534..6cb7c4d 100644
--- a/dev/core/src/com/google/gwt/dev/js/JsStaticEval.java
+++ b/dev/core/src/com/google/gwt/dev/js/JsStaticEval.java
@@ -33,15 +33,18 @@
import com.google.gwt.dev.js.ast.JsIf;
import com.google.gwt.dev.js.ast.JsModVisitor;
import com.google.gwt.dev.js.ast.JsNullLiteral;
+import com.google.gwt.dev.js.ast.JsNumberLiteral;
import com.google.gwt.dev.js.ast.JsPrefixOperation;
import com.google.gwt.dev.js.ast.JsProgram;
import com.google.gwt.dev.js.ast.JsStatement;
+import com.google.gwt.dev.js.ast.JsStringLiteral;
import com.google.gwt.dev.js.ast.JsUnaryOperation;
import com.google.gwt.dev.js.ast.JsUnaryOperator;
import com.google.gwt.dev.js.ast.JsValueLiteral;
import com.google.gwt.dev.js.ast.JsVars;
import com.google.gwt.dev.js.ast.JsVisitor;
import com.google.gwt.dev.js.ast.JsWhile;
+import com.google.gwt.dev.js.ast.JsBooleanLiteral;
import com.google.gwt.dev.js.ast.JsVars.JsVar;
import java.util.ArrayList;
@@ -163,6 +166,8 @@
trySimplifyEq(x, arg1, arg2, ctx);
} else if (op == JsBinaryOperator.NEQ) {
trySimplifyNe(x, arg1, arg2, ctx);
+ } else if (op == JsBinaryOperator.ADD) {
+ trySimplifyAdd(x, arg1, arg2, ctx);
}
}
@@ -449,6 +454,22 @@
return true;
}
+ private boolean appendLiteral(StringBuilder result, JsValueLiteral val) {
+ if (val instanceof JsNumberLiteral) {
+ double number = ((JsNumberLiteral) val).getValue();
+ result.append(fixTrailingZeroes(String.valueOf(number)));
+ } else if (val instanceof JsStringLiteral) {
+ result.append(((JsStringLiteral) val).getValue());
+ } else if (val instanceof JsBooleanLiteral) {
+ result.append(((JsBooleanLiteral) val).getValue());
+ } else if (val instanceof JsNullLiteral) {
+ result.append("null");
+ } else {
+ return false;
+ }
+ return true;
+ }
+
/**
* This method MUST be called whenever any statements are removed from a
* function. This is because some statements, such as JsVars or JsFunction
@@ -480,6 +501,20 @@
}
}
+ /*
+ * String.valueOf(Double) produces trailing .0 on integers which is
+ * incorrect for Javascript which produces conversions to string without
+ * trailing zeroes. Without this, int + String will turn out wrong.
+ */
+ private String fixTrailingZeroes(String num) {
+ if (num.endsWith(".0")) {
+ String fixNum = num.substring(0, num.length() - 2);
+ assert Double.parseDouble(fixNum) == Double.parseDouble(num);
+ num = fixNum;
+ }
+ return num;
+ }
+
private SourceInfo makeSourceInfo(HasSourceInfo x, String m) {
return x.getSourceInfo().makeChild(StaticEvalVisitor.class, m);
}
@@ -550,6 +585,30 @@
return original;
}
+ /**
+ * Simplify a + b.
+ */
+ private void trySimplifyAdd(JsExpression original, JsExpression arg1,
+ JsExpression arg2, JsContext<JsExpression> ctx) {
+ if (arg1 instanceof JsValueLiteral && arg2 instanceof JsValueLiteral) {
+ // case: number + number
+ if (arg1 instanceof JsNumberLiteral &&
+ arg2 instanceof JsNumberLiteral) {
+ ctx.replaceMe(program.getNumberLiteral(
+ ((JsNumberLiteral) arg1).getValue() +
+ ((JsNumberLiteral) arg2).getValue()));
+ } else {
+ // cases: number + string or string + number
+ StringBuilder result = new StringBuilder();
+ if (appendLiteral(result, (JsValueLiteral) arg1) &&
+ appendLiteral(result, (JsValueLiteral) arg2)) {
+ ctx.replaceMe(program.getStringLiteral(original.getSourceInfo(),
+ result.toString()));
+ }
+ }
+ }
+ }
+
private void trySimplifyEq(JsExpression original, JsExpression arg1,
JsExpression arg2, JsContext<JsExpression> ctx) {
JsExpression updated = simplifyEq(original, arg1, arg2);
diff --git a/dev/core/test/com/google/gwt/dev/js/JsStaticEvalTest.java b/dev/core/test/com/google/gwt/dev/js/JsStaticEvalTest.java
index 52e6bc9..ea54e44 100644
--- a/dev/core/test/com/google/gwt/dev/js/JsStaticEvalTest.java
+++ b/dev/core/test/com/google/gwt/dev/js/JsStaticEvalTest.java
@@ -20,6 +20,16 @@
*/
public class JsStaticEvalTest extends OptimizerTestBase {
+ public void testAddLiterals() throws Exception {
+ assertEquals("alert(42);", optimize("alert(21+21);"));
+ assertEquals("alert('Hello World');", optimize("alert('Hello '+'World');"));
+ assertEquals("alert('Hello 42');", optimize("alert('Hello ' + 42);"));
+ assertEquals("alert('42 Hello');", optimize("alert(42 + ' Hello');"));
+ assertEquals("alert('42 Hello');", optimize("alert(42.0 + ' Hello');"));
+ assertEquals("alert('42.2 Hello');", optimize("alert(42.2 + ' Hello');"));
+ assertEquals("alert('Hello 42.2');", optimize("alert('Hello ' + 42.2);"));
+ }
+
public void testIfWithEmptyThen() throws Exception {
assertEquals("a();", optimize("if (a()) { }"));
}
