Rewrite of VisitCountOperation that should speed it up

test/mjsunit/constant-folding.js

+// Copyright 2009 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Test operations that involve one or more constants.
+// The code generator now handles compile-time constants specially.
+// Test the code generated when operands are known at compile time
+
+// Test count operations involving constants
+function test_count() {
+  var x = "foo";
+  var y = "3";
+
+  x += x++;  // ++ and -- apply ToNumber to their operand, even for postfix.
+  assertEquals(x, "fooNaN", "fooNaN test");
+  x = "luft";
+  x += ++x;
+  assertEquals(x, "luftNaN", "luftNaN test");
+
+  assertTrue(y++ === 3, "y++ === 3, where y = \"3\"");
+  y = 3;
+  assertEquals(y++, 3, "y++ == 3, where y = 3");
+  y = "7.1";
+  assertTrue(y++ === 7.1, "y++ === 7.1, where y = \"7.1\"");
+  var z = y = x = "9";
+  assertEquals( z++ + (++y) + x++, 28, "z++ + (++y) + x++ == 28");
+  z = y = x = 13;
+  assertEquals( z++ + (++y) + x++, 40, "z++ + (++y) + x++ == 40");
+  z = y = x = -5.5;
+  assertEquals( z++ + (++y) + x++, -15.5, "z++ + (++y) + x++ == -15.5");
+
+  assertEquals(y, -4.5);
+  z = y;
+  z++;
+  assertEquals(y, -4.5);
+  z = y;
+  y++;
+  assertEquals(z, -4.5);
+
+  y = 20;
+  z = y;
+  z++;
+  assertEquals(y, 20);
+  z = y;
+  y++;
+  assertEquals(z, 20);
+
+  const w = 30;
+  assertEquals(w++, 30);
+  assertEquals(++w, 31);
+  assertEquals(++w, 31);
+}
+
+test_count();
+
+// Test comparison operations that involve one or two constant smis.
+
+function test() {
+  var i = 5;
+  var j = 3;
+
+  assertTrue( j < i );
+  i = 5; j = 3;
+  assertTrue( j <= i );
+  i = 5; j = 3;
+  assertTrue( i > j );
+  i = 5; j = 3;
+  assertTrue( i >= j );
+  i = 5; j = 3;
+  assertTrue( i != j );
+  i = 5; j = 3;
+  assertTrue( i == i );
+  i = 5; j = 3;
+  assertFalse( i < j );
+  i = 5; j = 3;
+  assertFalse( i <= j );
+  i = 5; j = 3;
+  assertFalse( j > i );
+  i = 5; j = 3;
+  assertFalse(j >= i );
+  i = 5; j = 3;
+  assertFalse( j == i);
+  i = 5; j = 3;
+  assertFalse( i != i);
+
+  i = 10 * 10;
+  while ( i < 107 ) {
+    ++i;
+  }
+  j = 21;
+
+  assertTrue( j < i );
+  j = 21;
+  assertTrue( j <= i );
+  j = 21;
+  assertTrue( i > j );
+  j = 21;
+  assertTrue( i >= j );
+  j = 21;
+  assertTrue( i != j );
+  j = 21;
+  assertTrue( i == i );
+  j = 21;
+  assertFalse( i < j );
+  j = 21;
+  assertFalse( i <= j );
+  j = 21;
+  assertFalse( j > i );
+  j = 21;
+  assertFalse(j >= i );
+  j = 21;
+  assertFalse( j == i);
+  j = 21;
+  assertFalse( i != i);
+  j = 21;
+  assertTrue( j == j );
+  j = 21;
+  assertFalse( j != j );
+
+  assertTrue( 100 > 99 );
+  assertTrue( 101 >= 90 );
+  assertTrue( 11111 > -234 );
+  assertTrue( -888 <= -20 );
+
+  while ( 234 > 456 ) {
+    i = i + 1;
+  }
+
+  switch(3) {
+    case 5:
+      assertUnreachable();
+      break;
+    case 3:
+      j = 13;
+    default:
+      i = 2;
+    case 7:
+      j = 17;
+      break;
+    case 9:
+      j = 19;
+      assertUnreachable();
+      break;
+  }
+  assertEquals(17, j, "switch with constant value");
+}
+
+test();