[compiler-rt] fb1c515 - Revert "[NFC][sanitizer] constexpr a few functions"

[Vitaly Buka via llvm-commits]

Author: Vitaly Buka
Date: 2021-10-24T19:26:55-07:00
New Revision: fb1c515d3b124741485f53d5f3ec6850bc4037b4

URL: https://github.com/llvm/llvm-project/commit/fb1c515d3b124741485f53d5f3ec6850bc4037b4
DIFF: https://github.com/llvm/llvm-project/commit/fb1c515d3b124741485f53d5f3ec6850bc4037b4.diff

LOG: Revert "[NFC][sanitizer] constexpr a few functions"

This reverts a part of commit 8cd51a69e5b4cf9513eb4f416f113058ebd8f257
and 5bf24f0581ee7ab9971b4050497375464b894c59 to fix Windows.

Added: 
    

Modified: 
    compiler-rt/lib/sanitizer_common/sanitizer_common.h
    compiler-rt/lib/sanitizer_common/sanitizer_flat_map.h

Removed: 
    


################################################################################
diff  --git a/compiler-rt/lib/sanitizer_common/sanitizer_common.h b/compiler-rt/lib/sanitizer_common/sanitizer_common.h
index b720d99d0d9d..f680aadc3c98 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common.h
@@ -385,9 +385,9 @@ unsigned char _BitScanReverse64(unsigned long *index, unsigned __int64 mask);
 }
 #endif
 
-inline constexpr uptr MostSignificantSetBitIndex(uptr x) {
+inline uptr MostSignificantSetBitIndex(uptr x) {
   CHECK_NE(x, 0U);
-  unsigned long up = 0;
+  unsigned long up;
 #if !SANITIZER_WINDOWS || defined(__clang__) || defined(__GNUC__)
 # ifdef _WIN64
   up = SANITIZER_WORDSIZE - 1 - __builtin_clzll(x);
@@ -402,9 +402,9 @@ inline constexpr uptr MostSignificantSetBitIndex(uptr x) {
   return up;
 }
 
-inline constexpr uptr LeastSignificantSetBitIndex(uptr x) {
+inline uptr LeastSignificantSetBitIndex(uptr x) {
   CHECK_NE(x, 0U);
-  unsigned long up = 0;
+  unsigned long up;
 #if !SANITIZER_WINDOWS || defined(__clang__) || defined(__GNUC__)
 # ifdef _WIN64
   up = __builtin_ctzll(x);
@@ -421,7 +421,7 @@ inline constexpr uptr LeastSignificantSetBitIndex(uptr x) {
 
 inline constexpr bool IsPowerOfTwo(uptr x) { return (x & (x - 1)) == 0; }
 
-inline constexpr uptr RoundUpToPowerOfTwo(uptr size) {
+inline uptr RoundUpToPowerOfTwo(uptr size) {
   CHECK(size);
   if (IsPowerOfTwo(size)) return size;
 
@@ -444,7 +444,7 @@ inline constexpr bool IsAligned(uptr a, uptr alignment) {
   return (a & (alignment - 1)) == 0;
 }
 
-inline constexpr uptr Log2(uptr x) {
+inline uptr Log2(uptr x) {
   CHECK(IsPowerOfTwo(x));
   return LeastSignificantSetBitIndex(x);
 }

diff  --git a/compiler-rt/lib/sanitizer_common/sanitizer_flat_map.h b/compiler-rt/lib/sanitizer_common/sanitizer_flat_map.h
index 0f7467c47e73..e8c34c1e13fd 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_flat_map.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_flat_map.h
@@ -65,9 +65,7 @@ template <typename T, u64 kSize1, u64 kSize2,
           typename AddressSpaceViewTy = LocalAddressSpaceView,
           class MapUnmapCallback = NoOpMapUnmapCallback>
 class TwoLevelMap {
-  static_assert(IsPowerOfTwo(kSize2), "");
-  static constexpr uptr kSize2Shift = Log2(kSize2);
-  static constexpr uptr kSize2Mask = kSize2 - 1;
+  static_assert(IsPowerOfTwo(kSize2), "Use a power of two for performance.");
 
  public:
   using AddressSpaceView = AddressSpaceViewTy;
@@ -104,19 +102,19 @@ class TwoLevelMap {
 
   bool contains(uptr idx) const {
     CHECK_LT(idx, kSize1 * kSize2);
-    return Get(idx >> kSize2Shift);
+    return Get(idx / kSize2);
   }
 
   const T &operator[](uptr idx) const {
     DCHECK_LT(idx, kSize1 * kSize2);
-    T *map2 = GetOrCreate(idx >> kSize2Shift);
-    return *AddressSpaceView::Load(&map2[idx & kSize2Mask]);
+    T *map2 = GetOrCreate(idx / kSize2);
+    return *AddressSpaceView::Load(&map2[idx % kSize2]);
   }
 
   T &operator[](uptr idx) {
     DCHECK_LT(idx, kSize1 * kSize2);
-    T *map2 = GetOrCreate(idx >> kSize2Shift);
-    return *AddressSpaceView::LoadWritable(&map2[idx & kSize2Mask]);
+    T *map2 = GetOrCreate(idx / kSize2);
+    return *AddressSpaceView::LoadWritable(&map2[idx % kSize2]);
   }
 
  private: