From 659bca56a707f036651a51d7d6943eb1c719200c Mon Sep 17 00:00:00 2001
From: Timur Iskhodzhanov <timurrrr@google.com>
Date: Fri, 8 Feb 2013 11:45:04 +0000
Subject: [PATCH] [ASan] Move functions using BitScan/clzl to sanitizer_common

llvm-svn: 174706
---
 compiler-rt/lib/asan/asan_allocator.h              | 45 ------------------
 .../lib/sanitizer_common/sanitizer_common.h        | 53 ++++++++++++++++++++++
 2 files changed, 53 insertions(+), 45 deletions(-)

diff --git a/compiler-rt/lib/asan/asan_allocator.h b/compiler-rt/lib/asan/asan_allocator.h
index 724dbe8..06cabe6 100644
--- a/compiler-rt/lib/asan/asan_allocator.h
+++ b/compiler-rt/lib/asan/asan_allocator.h
@@ -226,50 +226,5 @@ void asan_mz_force_unlock();
 
 void PrintInternalAllocatorStats();
 
-// Log2 and RoundUpToPowerOfTwo should be inlined for performance.
-#if defined(_WIN32) && !defined(__clang__)
-extern "C" {
-unsigned char _BitScanForward(unsigned long *index, unsigned long mask);  // NOLINT
-unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);  // NOLINT
-#if defined(_WIN64)
-unsigned char _BitScanForward64(unsigned long *index, unsigned __int64 mask);  // NOLINT
-unsigned char _BitScanReverse64(unsigned long *index, unsigned __int64 mask);  // NOLINT
-#endif
-}
-#endif
-
-static inline uptr Log2(uptr x) {
-  CHECK(IsPowerOfTwo(x));
-#if !defined(_WIN32) || defined(__clang__)
-  return __builtin_ctzl(x);
-#elif defined(_WIN64)
-  unsigned long ret;  // NOLINT
-  _BitScanForward64(&ret, x);
-  return ret;
-#else
-  unsigned long ret;  // NOLINT
-  _BitScanForward(&ret, x);
-  return ret;
-#endif
-}
-
-static inline uptr RoundUpToPowerOfTwo(uptr size) {
-  CHECK(size);
-  if (IsPowerOfTwo(size)) return size;
-
-  unsigned long up;  // NOLINT
-#if !defined(_WIN32) || defined(__clang__)
-  up = SANITIZER_WORDSIZE - 1 - __builtin_clzl(size);
-#elif defined(_WIN64)
-  _BitScanReverse64(&up, size);
-#else
-  _BitScanReverse(&up, size);
-#endif
-  CHECK(size < (1ULL << (up + 1)));
-  CHECK(size > (1ULL << up));
-  return 1UL << (up + 1);
-}
-
-
 }  // namespace __asan
 #endif  // ASAN_ALLOCATOR_H
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common.h b/compiler-rt/lib/sanitizer_common/sanitizer_common.h
index b0501db..ef09594 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common.h
@@ -165,19 +165,72 @@ void ReportErrorSummary(const char *error_type, const char *file,
                         int line, const char *function);
 
 // Math
+#if defined(_WIN32) && !defined(__clang__)
+extern "C" {
+unsigned char _BitScanForward(unsigned long *index, unsigned long mask);  // NOLINT
+unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);  // NOLINT
+#if defined(_WIN64)
+unsigned char _BitScanForward64(unsigned long *index, unsigned __int64 mask);  // NOLINT
+unsigned char _BitScanReverse64(unsigned long *index, unsigned __int64 mask);  // NOLINT
+#endif
+}
+#endif
+
+INLINE uptr MostSignificantSetBitIndex(uptr x) {
+  CHECK(x != 0);
+  unsigned long up;  // NOLINT
+#if !defined(_WIN32) || defined(__clang__)
+  up = SANITIZER_WORDSIZE - 1 - __builtin_clzl(x);
+#elif defined(_WIN64)
+  _BitScanReverse64(&up, x);
+#else
+  _BitScanReverse(&up, x);
+#endif
+  return up;
+}
+
 INLINE bool IsPowerOfTwo(uptr x) {
   return (x & (x - 1)) == 0;
 }
+
+INLINE uptr RoundUpToPowerOfTwo(uptr size) {
+  CHECK(size);
+  if (IsPowerOfTwo(size)) return size;
+
+  uptr up = MostSignificantSetBitIndex(size);
+  CHECK(size < (1ULL << (up + 1)));
+  CHECK(size > (1ULL << up));
+  return 1UL << (up + 1);
+}
+
 INLINE uptr RoundUpTo(uptr size, uptr boundary) {
   CHECK(IsPowerOfTwo(boundary));
   return (size + boundary - 1) & ~(boundary - 1);
 }
+
 INLINE uptr RoundDownTo(uptr x, uptr boundary) {
   return x & ~(boundary - 1);
 }
+
 INLINE bool IsAligned(uptr a, uptr alignment) {
   return (a & (alignment - 1)) == 0;
 }
+
+INLINE uptr Log2(uptr x) {
+  CHECK(IsPowerOfTwo(x));
+#if !defined(_WIN32) || defined(__clang__)
+  return __builtin_ctzl(x);
+#elif defined(_WIN64)
+  unsigned long ret;  // NOLINT
+  _BitScanForward64(&ret, x);
+  return ret;
+#else
+  unsigned long ret;  // NOLINT
+  _BitScanForward(&ret, x);
+  return ret;
+#endif
+}
+
 // Don't use std::min, std::max or std::swap, to minimize dependency
 // on libstdc++.
 template<class T> T Min(T a, T b) { return a < b ? a : b; }
-- 
2.7.4