builtins.c (java_builtins): Use popcount* and bswap* builtins to implement bitCount() and reverseBytes()...

2016-05-31  Roger Sayle  <roger@nextmovesoftware.com>

gcc/java:
	* builtins.c (java_builtins): Use popcount* and bswap* builtins to
	implement bitCount() and reverseBytes() methods in java.lang.Integer
	and friends.
	(initialize_builtins): Annotate math builtins with ECF_LEAF.  Call
	define_builtin for the new popcount* and bswap* builtins.

libjava:
	* testsuite/libjava.lang/BuiltinBitCount.java: New test case.
	* testsuite/libjava.lang/BuiltinReverseBytes.java: Likewise.

From-SVN: r236919

1 files changed, 51 insertions, 0 deletions

diff --git a/libjava/testsuite/libjava.lang/BuiltinBitCount.java b/libjava/testsuite/libjava.lang/BuiltinBitCount.java
new file mode 100644
index 0000000..bcafd31
--- /dev/null
+++ b/libjava/testsuite/libjava.lang/BuiltinBitCount.java
@@ -0,0 +1,51 @@
+class BuiltinBitCount
+{
+  public static int popcount(int x)
+  {
+    return Integer.bitCount(x);
+  }
+
+  public static int popcountl(long x)
+  {
+    return Long.bitCount(x);
+  }
+
+  public static void main(String[] args)
+  {
+    if (Integer.bitCount(0) != 0)
+      throw new Error();
+    if (Integer.bitCount(8) != 1)
+      throw new Error();
+    if (Integer.bitCount(123456) != 6)
+      throw new Error();
+    if (Integer.bitCount(-1) != 32)
+      throw new Error();
+    
+    if (Long.bitCount(0) != 0)
+      throw new Error();
+    if (Long.bitCount(8) != 1)
+      throw new Error();
+    if (Long.bitCount(123456) != 6)
+      throw new Error();
+    if (Long.bitCount(-1) != 64)
+      throw new Error();
+
+    if (popcount(0) != 0)
+      throw new Error();
+    if (popcount(8) != 1)
+      throw new Error();
+    if (popcount(123456) != 6)
+      throw new Error();
+    if (popcount(-1) != 32)
+      throw new Error();
+
+    if (popcountl(0) != 0)
+      throw new Error();
+    if (popcountl(8) != 1)
+      throw new Error();
+    if (popcountl(123456) != 6)
+      throw new Error();
+    if (popcountl(-1) != 64)
+      throw new Error();
+  }
+}