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-rw-r--r--test/411-optimizing-arith/src/Main.java34
1 files changed, 34 insertions, 0 deletions
diff --git a/test/411-optimizing-arith/src/Main.java b/test/411-optimizing-arith/src/Main.java
index a22c516ff4..4de2271ebd 100644
--- a/test/411-optimizing-arith/src/Main.java
+++ b/test/411-optimizing-arith/src/Main.java
@@ -74,6 +74,7 @@ public class Main {
public static void main(String[] args) {
mul();
+ neg();
}
public static void mul() {
@@ -163,6 +164,34 @@ public class Main {
expectEquals(Double.POSITIVE_INFINITY, $opt$Mul(Double.NEGATIVE_INFINITY, Double.NEGATIVE_INFINITY));
}
+ public static void neg() {
+ expectEquals(-1, $opt$Neg(1));
+ expectEquals(1, $opt$Neg(-1));
+ expectEquals(0, $opt$Neg(0));
+ expectEquals(51, $opt$Neg(-51));
+ expectEquals(-51, $opt$Neg(51));
+ expectEquals(2147483647, $opt$Neg(-2147483647)); // (2^31 - 1)
+ expectEquals(-2147483647, $opt$Neg(2147483647)); // -(2^31 - 1)
+ // From the Java 7 SE Edition specification:
+ // http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.15.4
+ //
+ // For integer values, negation is the same as subtraction from
+ // zero. The Java programming language uses two's-complement
+ // representation for integers, and the range of two's-complement
+ // values is not symmetric, so negation of the maximum negative
+ // int or long results in that same maximum negative number.
+ // Overflow occurs in this case, but no exception is thrown.
+ // For all integer values x, -x equals (~x)+1.''
+ expectEquals(-2147483648, $opt$Neg(-2147483648)); // -(2^31)
+
+ $opt$InplaceNegOne(1);
+ }
+
+ public static void $opt$InplaceNegOne(int a) {
+ a = -a;
+ expectEquals(-1, a);
+ }
+
static int $opt$Mul(int a, int b) {
return a * b;
}
@@ -178,4 +207,9 @@ public class Main {
static double $opt$Mul(double a, double b) {
return a * b;
}
+
+ static int $opt$Neg(int a){
+ return -a;
+ }
+
}