8248043: Need to eliminate excessive i2l conversions

Backport-of: 6d137a3

src/hotspot/share/opto/subnode.cpp

@@ -723,6 +723,16 @@ Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
   return NULL;                  // No change
 }
 
+Node *CmpLNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
+  const TypeLong *t2 = phase->type(in(2))->isa_long();
+  if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) {
+    const jlong con = t2->get_con();
+    if (con >= min_jint && con <= max_jint) {
+      return new CmpINode(in(1)->in(1), phase->intcon((jint)con));
+    }
+  }
+  return NULL;
+}
 
 //=============================================================================
 // Simplify a CmpL (compare 2 longs ) node, based on local information.

src/hotspot/share/opto/subnode.hpp

@@ -195,6 +195,7 @@ class CmpLNode : public CmpNode {
 public:
   CmpLNode( Node *in1, Node *in2 ) : CmpNode(in1,in2) {}
   virtual int    Opcode() const;
+  virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
   virtual const Type *sub( const Type *, const Type * ) const;
 };
 

test/hotspot/jtreg/compiler/c2/TestSkipLongToIntCast.java

@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) BELLSOFT. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package compiler.c2;
+
+/*
+ * @test
+ * @bug 8248043
+ * @summary Functional test to enshure CmpL(int value, long constant) is not broken
+ *
+ * @run main/othervm -XX:-TieredCompilation -XX:CompileOnly=compiler.c2.TestSkipLongToIntCast::cmplTest
+ *      compiler.c2.TestSkipLongToIntCast
+ */
+public class TestSkipLongToIntCast {
+
+    public static int[] pos = {0, 1, 2, 3};
+    public static int[] neg = {0, -1, -2, -3};
+    public static int[] max = {2147483647, 2147483646, 2147483645, 2147483644};
+    public static int[] min = {-2147483648, -2147483647, -2147483646, -2147483645};
+    public static int[] out = {(int)2147483648L, (int)-2147483649L, (int)Long.MAX_VALUE, (int)Long.MIN_VALUE};
+
+    // Testing cmp(int value, long constant) expressions as they are updated
+    // on Ideal graph level: i2l conversion is skipped when possible.
+    public static void cmplTest() throws Exception {
+        // values around zero
+        if (pos[0] != 0L) { throw new Exception("pos[0] is " + pos[0]); }
+        if (pos[1] != 1L) { throw new Exception("pos[1] is " + pos[1]); }
+        if (pos[2] != 2L) { throw new Exception("pos[2] is " + pos[2]); }
+        if (pos[3] != 3L) { throw new Exception("pos[3] is " + pos[3]); }
+
+        if (neg[0] != -0L) { throw new Exception("neg[0] is " + neg[0]); }
+        if (neg[1] != -1L) { throw new Exception("neg[1] is " + neg[1]); }
+        if (neg[2] != -2L) { throw new Exception("neg[2] is " + neg[2]); }
+        if (neg[3] != -3L) { throw new Exception("neg[3] is " + neg[3]); }
+
+        // values near the ends of Integer range
+        if (max[0] != 2147483647L) { throw new Exception("max[0] is " + max[0]); }
+        if (max[1] != 2147483646L) { throw new Exception("max[1] is " + max[1]); }
+        if (max[2] != 2147483645L) { throw new Exception("max[2] is " + max[2]); }
+        if (max[3] != 2147483644L) { throw new Exception("max[3] is " + max[3]); }
+
+        if (min[0] != -2147483648L) { throw new Exception("min[0] is " + min[0]); }
+        if (min[1] != -2147483647L) { throw new Exception("min[1] is " + min[1]); }
+        if (min[2] != -2147483646L) { throw new Exception("min[2] is " + min[2]); }
+        if (min[3] != -2147483645L) { throw new Exception("min[3] is " + min[3]); }
+
+        // constants outside of the Integer range
+        if (out[0] == 2147483648L)  { throw new Exception("out[0] is " + out[0]); }
+        if (out[1] == -2147483649L) { throw new Exception("out[1] is " + out[1]); }
+        if (out[2] == Long.MAX_VALUE) { throw new Exception("out[2] is " + out[2]); }
+        if (out[3] == Long.MIN_VALUE) { throw new Exception("out[3] is " + out[3]); }
+    }
+
+    // similar test with long constant on LHS
+    public static void cmplTest_LHS() throws Exception {
+        // values around zero
+        if (0L != pos[0]) { throw new Exception("LHS: pos[0] is " + pos[0]); }
+        if (1L != pos[1]) { throw new Exception("LHS: pos[1] is " + pos[1]); }
+        if (2L != pos[2]) { throw new Exception("LHS: pos[2] is " + pos[2]); }
+        if (3L != pos[3]) { throw new Exception("LHS: pos[3] is " + pos[3]); }
+
+        if (-0L != neg[0]) { throw new Exception("LHS: neg[0] is " + neg[0]); }
+        if (-1L != neg[1]) { throw new Exception("LHS: neg[1] is " + neg[1]); }
+        if (-2L != neg[2]) { throw new Exception("LHS: neg[2] is " + neg[2]); }
+        if (-3L != neg[3]) { throw new Exception("LHS: neg[3] is " + neg[3]); }
+
+        // values near the ends of Integer range
+        if (2147483647L != max[0]) { throw new Exception("LHS: max[0] is " + max[0]); }
+        if (2147483646L != max[1]) { throw new Exception("LHS: max[1] is " + max[1]); }
+        if (2147483645L != max[2]) { throw new Exception("LHS: max[2] is " + max[2]); }
+        if (2147483644L != max[3]) { throw new Exception("LHS: max[3] is " + max[3]); }
+
+        if (-2147483648L != min[0]) { throw new Exception("LHS: min[0] is " + min[0]); }
+        if (-2147483647L != min[1]) { throw new Exception("LHS: min[1] is " + min[1]); }
+        if (-2147483646L != min[2]) { throw new Exception("LHS: min[2] is " + min[2]); }
+        if (-2147483645L != min[3]) { throw new Exception("LHS: min[3] is " + min[3]); }
+
+        // constants outside of the Integer range
+        if (2147483648L == out[0])  { throw new Exception("LHS: out[0] is " + out[0]); }
+        if (-2147483649L == out[1]) { throw new Exception("LHS: out[1] is " + out[1]); }
+        if (Long.MAX_VALUE == out[2]) { throw new Exception("LHS: out[2] is " + out[2]); }
+        if (Long.MIN_VALUE == out[3]) { throw new Exception("LHS: out[3] is " + out[3]); }
+    }
+
+    public static void main(String[] args) throws Exception {
+        for (int i = 0; i < 100_000; i++) {
+            cmplTest();
+            cmplTest_LHS();
+        }
+    }
+}

test/micro/org/openjdk/bench/vm/compiler/SkipIntToLongCast.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) BELLSOFT. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package org.openjdk.bench.vm.compiler;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Fork;
+import org.openjdk.jmh.annotations.Measurement;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.Setup;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.annotations.Warmup;
+
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.AverageTime)
+@OutputTimeUnit(TimeUnit.NANOSECONDS)
+@State(Scope.Thread)
+@Warmup(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS)
+@Measurement(iterations = 5, time = 1000, timeUnit = TimeUnit.MILLISECONDS)
+@Fork(3)
+public class SkipIntToLongCast {
+
+    private static final long ARRAYSIZE_L = 40L;
+
+    public int[] intValues;
+
+    @Setup
+    public void setup() {
+        int size = (int)ARRAYSIZE_L;
+        intValues = new int[size];
+        for (int i = 0; i < size; i++) {
+            intValues[i] = i + 1;
+        }
+    }
+
+    @Benchmark
+    public int skipCastTestRight() {
+        for (int i = 0; i < ARRAYSIZE_L; i++) {
+            if (intValues[i] == ARRAYSIZE_L) {
+                return i;
+            }
+        }
+        return 0;
+    }
+
+    @Benchmark
+    public int skipCastTestLeft() {
+        for (int i = 0; i < ARRAYSIZE_L; i++) {
+            if (ARRAYSIZE_L == intValues[i]) {
+                return i;
+            }
+        }
+        return 0;
+    }
+}