Fix MSVC-related build issues (#7439)

Summary:
This PR addresses some build and functional issues on MSVC targets, as a step towards an eventual goal of having RocksDB build successfully for Windows on ARM64.

Addressed issues include:
- BitsSetToOne and CountTrailingZeroBits do not compile on non-x64 MSVC targets. A fallback implementation of BitsSetToOne when Intel intrinsics are not available is added, based on the C++20 `<bit>` popcount implementation in Microsoft's STL.
- The implementation of FloorLog2 for MSVC targets (including x64) gives incorrect results. The unit test easily detects this, but CircleCI is currently configured to only run a specific set of tests for Windows CMake builds, so this seems to have been unnoticed.
- AsmVolatilePause does not use YieldProcessor on Windows ARM64 targets, even though it is available.
- When CondVar::TimedWait calls Microsoft STL's condition_variable::wait_for, it can potentially trigger a bug (just recently fixed in the upcoming VS 16.8's STL) that deadlocks various tests that wait for a timer to execute, since `Timer::Run` doesn't get a chance to execute before being blocked by the test function acquiring the mutex.
- In c_test, `GetTempDir` assumes a POSIX-style temp path.
- `NormalizePath` did not eliminate consecutive POSIX-style path separators on Windows, resulting in test failures in e.g., wal_manager_test.
- Various other test failures.

In a followup PR I hope to modify CircleCI's config.yml to invoke all RocksDB unit tests in Windows CMake builds with CTest, instead of the current use of `run_ci_db_test.ps1` which requires individual tests to be specified and is missing many of the existing tests.

Notes from peterd: FloorLog2 is not yet used in production code (it's for something in progress). I also added a few more inexpensive platform-dependent tests to Windows CircleCI runs. And included facebook/folly#1461 as requested

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7439

Reviewed By: jay-zhuang

Differential Revision: D24021563

Pulled By: pdillinger

fbshipit-source-id: 0ec2027c0d6a494d8a0fe38d9667fc2f7e29f7e7

.circleci/config.yml

@@ -276,7 +276,7 @@ jobs:
           name: "Test RocksDB"
           shell: powershell.exe
           command: |
-            build_tools\run_ci_db_test.ps1 -SuiteRun db_basic_test,db_test,db_test2,env_basic_test,env_test,db_merge_operand_test -Concurrency 16
+            build_tools\run_ci_db_test.ps1 -SuiteRun db_basic_test,db_test,db_test2,db_merge_operand_test,bloom_test,c_test,coding_test,crc32c_test,dynamic_bloom_test,env_basic_test,env_test,hash_test,random_test -Concurrency 16
 
   build-linux-java:
     machine:

db/c_test.c

@@ -58,7 +58,11 @@ static void StartPhase(const char* name) {
 static const char* GetTempDir(void) {
     const char* ret = getenv("TEST_TMPDIR");
     if (ret == NULL || ret[0] == '\0')
+#ifdef OS_WIN
+      ret = getenv("TEMP");
+#else
       ret = "/tmp";
+#endif
     return ret;
 }
 #ifdef _MSC_VER

db/perf_context_test.cc

@@ -817,6 +817,13 @@ TEST_F(PerfContextTest, PerfContextByLevelGetSet) {
 }
 
 TEST_F(PerfContextTest, CPUTimer) {
+  if (Env::Default()->NowCPUNanos() == 0) {
+    // TODO: This should be a GTEST_SKIP when the embedded gtest is updated
+    // to 1.10 or higher.
+    GTEST_SUCCESS_("Skipped on target without NowCPUNanos support");
+    return;
+  }
+
   DestroyDB(kDbName, Options());
   auto db = OpenDb();
   WriteOptions write_options;

file/filename.cc

@@ -461,8 +461,8 @@ Status GetInfoLogFiles(Env* env, const std::string& db_log_dir,
 std::string NormalizePath(const std::string& path) {
   std::string dst;
   for (auto c : path) {
-    if (!dst.empty() && c == kFilePathSeparator &&
-        dst.back() == kFilePathSeparator) {
+    if (!dst.empty() && (c == kFilePathSeparator || c == '/') &&
+        (dst.back() == kFilePathSeparator || dst.back() == '/')) {
       continue;
     }
     dst.push_back(c);

port/win/port_win.cc

@@ -98,6 +98,15 @@ bool CondVar::TimedWait(uint64_t abs_time_us) {
 
   // Caller must ensure that mutex is held prior to calling this method
   std::unique_lock<std::mutex> lk(mu_->getLock(), std::adopt_lock);
+
+  // Work around https://github.com/microsoft/STL/issues/369
+#if defined(_MSC_VER) && \
+    (!defined(_MSVC_STL_UPDATE) || _MSVC_STL_UPDATE < 202008L)
+  if (relTimeUs == microseconds::zero()) {
+    lk.unlock();
+    lk.lock();
+  }
+#endif
 #ifndef NDEBUG
   mu_->locked_ = false;
 #endif

port/win/port_win.h

@@ -283,7 +283,7 @@ extern const size_t kPageSize;
 #endif
 
 static inline void AsmVolatilePause() {
-#if defined(_M_IX86) || defined(_M_X64)
+#if defined(_M_IX86) || defined(_M_X64) || defined(_M_ARM64) || defined(_M_ARM)
   YieldProcessor();
 #endif
   // it would be nice to get "wfe" on ARM here

third-party/folly/folly/chrono/Hardware.h

@@ -10,7 +10,7 @@
 #include <chrono>
 #include <cstdint>
 
-#if _MSC_VER
+#if _MSC_VER && (defined(_M_IX86) || defined(_M_X64))
 extern "C" std::uint64_t __rdtsc();
 #pragma intrinsic(__rdtsc)
 #endif
@@ -18,7 +18,7 @@ extern "C" std::uint64_t __rdtsc();
 namespace folly {
 
 inline std::uint64_t hardware_timestamp() {
-#if _MSC_VER
+#if _MSC_VER && (defined(_M_IX86) || defined(_M_X64))
   return __rdtsc();
 #elif __GNUC__ && (__i386__ || FOLLY_X64)
   return __builtin_ia32_rdtsc();

util/filelock_test.cc

@@ -127,9 +127,11 @@ TEST_F(LockTest, LockBySameThread) {
   // re-acquire the lock on the same file. This should fail.
   Status s = LockFile(&lock2);
   ASSERT_TRUE(s.IsIOError());
+#ifndef OS_WIN
   // Validate that error message contains current thread ID.
   ASSERT_TRUE(s.ToString().find(ToString(Env::Default()->GetThreadID())) !=
               std::string::npos);
+#endif
 
   // check the file is locked
   ASSERT_TRUE( AssertFileIsLocked() );

util/math.h

@@ -23,13 +23,23 @@ inline int FloorLog2(T v) {
   assert(v > 0);
 #ifdef _MSC_VER
   static_assert(sizeof(T) <= sizeof(uint64_t), "type too big");
-  unsigned long lz = 0;
+  unsigned long idx = 0;
   if (sizeof(T) <= sizeof(uint32_t)) {
-    _BitScanReverse(&lz, static_cast<uint32_t>(v));
+    _BitScanReverse(&idx, static_cast<uint32_t>(v));
   } else {
-    _BitScanReverse64(&lz, static_cast<uint64_t>(v));
+#if defined(_M_X64) || defined(_M_ARM64)
+    _BitScanReverse64(&idx, static_cast<uint64_t>(v));
+#else
+    const auto vh = static_cast<uint32_t>(static_cast<uint64_t>(v) >> 32);
+    if (vh != 0) {
+      _BitScanReverse(&idx, static_cast<uint32_t>(vh));
+      idx += 32;
+    } else {
+      _BitScanReverse(&idx, static_cast<uint32_t>(v));
     }
-  return 63 - static_cast<int>(lz);
+#endif
+  }
+  return idx;
 #else
   static_assert(sizeof(T) <= sizeof(unsigned long long), "type too big");
   if (sizeof(T) <= sizeof(unsigned int)) {
@@ -56,7 +66,16 @@ inline int CountTrailingZeroBits(T v) {
   if (sizeof(T) <= sizeof(uint32_t)) {
     _BitScanForward(&tz, static_cast<uint32_t>(v));
   } else {
+#if defined(_M_X64) || defined(_M_ARM64)
     _BitScanForward64(&tz, static_cast<uint64_t>(v));
+#else
+    _BitScanForward(&tz, static_cast<uint32_t>(v));
+    if (tz == 0) {
+      _BitScanForward(&tz,
+                      static_cast<uint32_t>(static_cast<uint64_t>(v) >> 32));
+      tz += 32;
+    }
+#endif
   }
   return static_cast<int>(tz);
 #else
@@ -71,6 +90,29 @@ inline int CountTrailingZeroBits(T v) {
 #endif
 }
 
+#if defined(_MSC_VER) && !defined(_M_X64)
+namespace detail {
+template <typename T>
+int BitsSetToOneFallback(T v) {
+  const int kBits = static_cast<int>(sizeof(T)) * 8;
+  static_assert((kBits & (kBits - 1)) == 0, "must be power of two bits");
+  // we static_cast these bit patterns in order to truncate them to the correct
+  // size
+  v = static_cast<T>(v - ((v >> 1) & static_cast<T>(0x5555555555555555ull)));
+  v = static_cast<T>((v & static_cast<T>(0x3333333333333333ull)) +
+                     ((v >> 2) & static_cast<T>(0x3333333333333333ull)));
+  v = static_cast<T>((v + (v >> 4)) & static_cast<T>(0x0F0F0F0F0F0F0F0Full));
+  for (int shift_bits = 8; shift_bits < kBits; shift_bits <<= 1) {
+    v += static_cast<T>(v >> shift_bits);
+  }
+  // we want the bottom "slot" that's big enough to represent a value up to
+  // (and including) kBits.
+  return static_cast<int>(v & static_cast<T>(kBits | (kBits - 1)));
+}
+
+}  // namespace detail
+#endif
+
 // Number of bits set to 1. Also known as "population count".
 template <typename T>
 inline int BitsSetToOne(T v) {
@@ -82,11 +124,27 @@ inline int BitsSetToOne(T v) {
     constexpr auto mm = 8 * sizeof(uint32_t) - 1;
     // The bit mask is to neutralize sign extension on small signed types
     constexpr uint32_t m = (uint32_t{1} << ((8 * sizeof(T)) & mm)) - 1;
+#if defined(_M_X64) || defined(_M_IX86)
     return static_cast<int>(__popcnt(static_cast<uint32_t>(v) & m));
+#else
+    return static_cast<int>(detail::BitsSetToOneFallback(v) & m);
+#endif
   } else if (sizeof(T) == sizeof(uint32_t)) {
+#if defined(_M_X64) || defined(_M_IX86)
     return static_cast<int>(__popcnt(static_cast<uint32_t>(v)));
+#else
+    return detail::BitsSetToOneFallback(static_cast<uint32_t>(v));
+#endif
   } else {
+#ifdef _M_X64
     return static_cast<int>(__popcnt64(static_cast<uint64_t>(v)));
+#elif defined(_M_IX86)
+    return static_cast<int>(
+        __popcnt(static_cast<uint32_t>(static_cast<uint64_t>(v) >> 32) +
+                 __popcnt(static_cast<uint32_t>(v))));
+#else
+    return detail::BitsSetToOneFallback(static_cast<uint64_t>(v));
+#endif
   }
 #else
   static_assert(sizeof(T) <= sizeof(unsigned long long), "type too big");

util/xxh3p.h

@@ -253,7 +253,9 @@ XXH_FORCE_INLINE U64x2 XXH_vec_mule(U32x4 a, U32x4 b) {
 #if defined(XXH_NO_PREFETCH)
 #  define XXH_PREFETCH(ptr)  (void)(ptr)  /* disabled */
 #else
-#  if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_I86))  /* _mm_prefetch() is not defined outside of x86/x64 */
+#if defined(_MSC_VER) && \
+    (defined(_M_X64) ||  \
+     defined(_M_IX86)) /* _mm_prefetch() is not defined outside of x86/x64 */
 #    include <mmintrin.h>   /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */
 #    define XXH_PREFETCH(ptr)  _mm_prefetch((const char*)(ptr), _MM_HINT_T0)
 #  elif defined(__GNUC__) && ( (__GNUC__ >= 4) || ( (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1) ) )