Fix a compiler bug caused by Utils::IsPowerOfTwo treating zero as a power of two.

runtime/vm/utils_test.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/assert.h"
 #include "platform/utils.h"
 #include "vm/unit_test.h"
 
 namespace dart {
 
@@ skipping 21 matching lines @@
 
   EXPECT_EQ(1, Utils::Maximum(-1, 1));
   EXPECT_EQ(1, Utils::Maximum(1, -1));
 
   EXPECT_EQ(-1, Utils::Maximum(-1, -2));
   EXPECT_EQ(-1, Utils::Maximum(-2, -1));
 }
 
 
 UNIT_TEST_CASE(IsPowerOfTwo) {
-  EXPECT(Utils::IsPowerOfTwo(0));
+  EXPECT(!Utils::IsPowerOfTwo(0));
   EXPECT(Utils::IsPowerOfTwo(1));
   EXPECT(Utils::IsPowerOfTwo(2));
   EXPECT(!Utils::IsPowerOfTwo(3));
   EXPECT(Utils::IsPowerOfTwo(4));
   EXPECT(Utils::IsPowerOfTwo(256));
 
   EXPECT(!Utils::IsPowerOfTwo(-1));
   EXPECT(!Utils::IsPowerOfTwo(-2));
 }
 
 
 UNIT_TEST_CASE(ShiftForPowerOfTwo) {
   EXPECT_EQ(1, Utils::ShiftForPowerOfTwo(2));
   EXPECT_EQ(2, Utils::ShiftForPowerOfTwo(4));
   EXPECT_EQ(8, Utils::ShiftForPowerOfTwo(256));
 }
 
 
 UNIT_TEST_CASE(IsAligned) {
-  EXPECT(Utils::IsAligned(0, 0));
   EXPECT(Utils::IsAligned(0, 1));
   EXPECT(Utils::IsAligned(1, 1));
 
   EXPECT(Utils::IsAligned(0, 2));
   EXPECT(!Utils::IsAligned(1, 2));
   EXPECT(Utils::IsAligned(2, 2));
 
   EXPECT(Utils::IsAligned(32, 8));
   EXPECT(!Utils::IsAligned(33, 8));
   EXPECT(Utils::IsAligned(40, 8));
 }
 
 
 UNIT_TEST_CASE(RoundDown) {
-  EXPECT_EQ(0, Utils::RoundDown(0, 0));
   EXPECT_EQ(0, Utils::RoundDown(22, 32));
   EXPECT_EQ(32, Utils::RoundDown(33, 32));
   EXPECT_EQ(32, Utils::RoundDown(63, 32));
   uword* address = reinterpret_cast<uword*>(63);
   uword* rounddown_address = reinterpret_cast<uword*>(32);
   EXPECT_EQ(rounddown_address, Utils::RoundDown(address, 32));
 }
 
 
 UNIT_TEST_CASE(RoundUp) {
-  EXPECT_EQ(0, Utils::RoundUp(0, 0));
-  EXPECT_EQ(0, Utils::RoundUp(1, 0));
   EXPECT_EQ(32, Utils::RoundUp(22, 32));
   EXPECT_EQ(64, Utils::RoundUp(33, 32));
   EXPECT_EQ(64, Utils::RoundUp(63, 32));
   uword* address = reinterpret_cast<uword*>(63);
   uword* roundup_address = reinterpret_cast<uword*>(64);
   EXPECT_EQ(roundup_address, Utils::RoundUp(address, 32));
 }
 
 
 UNIT_TEST_CASE(RoundUpToPowerOfTwo) {
@@ skipping 117 matching lines @@
   EXPECT_EQ(0xf3, reinterpret_cast<uint8_t*>(&value64le)[1]);
   EXPECT_EQ(0xf2, reinterpret_cast<uint8_t*>(&value64le)[2]);
   EXPECT_EQ(0xf1, reinterpret_cast<uint8_t*>(&value64le)[3]);
   EXPECT_EQ(0x0, reinterpret_cast<uint8_t*>(&value64le)[4]);
   EXPECT_EQ(0x0, reinterpret_cast<uint8_t*>(&value64le)[5]);
   EXPECT_EQ(0x0, reinterpret_cast<uint8_t*>(&value64le)[6]);
   EXPECT_EQ(0x0, reinterpret_cast<uint8_t*>(&value64le)[7]);
 }
 
 }  // namespace dart