diff options
Diffstat (limited to 'include/llvm/Support/MathExtras.h')
| -rw-r--r-- | include/llvm/Support/MathExtras.h | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/include/llvm/Support/MathExtras.h b/include/llvm/Support/MathExtras.h index 72065ba3d8..0f5961ff73 100644 --- a/include/llvm/Support/MathExtras.h +++ b/include/llvm/Support/MathExtras.h @@ -228,7 +228,7 @@ inline unsigned CountPopulation_64(uint64_t Value) { // Log2_32 - This function returns the floor log base 2 of the specified value, // -1 if the value is zero. (32 bit edition.) -// Ex. Log2_32(32) == 5, Log2_32(1) == 0, Log2_32(0) == -1 +// Ex. Log2_32(32) == 5, Log2_32(1) == 0, Log2_32(0) == -1, Log2_32(6) == 2 inline unsigned Log2_32(unsigned Value) { return 31 - CountLeadingZeros_32(Value); } @@ -239,6 +239,19 @@ inline unsigned Log2_64(uint64_t Value) { return 63 - CountLeadingZeros_64(Value); } +// Log2_32_Ceil - This function returns the ceil log base 2 of the specified +// value, 32 if the value is zero. (32 bit edition). +// Ex. Log2_32_Ceil(32) == 5, Log2_32_Ceil(1) == 0, Log2_32_Ceil(6) == 3 +inline unsigned Log2_32_Ceil(unsigned Value) { + return 32-CountLeadingZeros_32(Value-1); +} + +// Log2_64 - This function returns the ceil log base 2 of the specified value, +// 64 if the value is zero. (64 bit edition.) +inline unsigned Log2_64_Ceil(uint64_t Value) { + return 64-CountLeadingZeros_64(Value-1); +} + // BitsToDouble - This function takes a 64-bit integer and returns the bit // equivalent double. inline double BitsToDouble(uint64_t Bits) { |