diff options
Diffstat (limited to 'src/support/bits.cpp')
| -rw-r--r-- | src/support/bits.cpp | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/src/support/bits.cpp b/src/support/bits.cpp index 7bf00e595..c1de4da8b 100644 --- a/src/support/bits.cpp +++ b/src/support/bits.cpp @@ -17,8 +17,10 @@ #define wasm_support_bits_definitions #include "support/bits.h" +namespace wasm { + template<> -int wasm::PopCount<uint8_t>(uint8_t v) { +int PopCount<uint8_t>(uint8_t v) { // Small table lookup. static const uint8_t tbl[32] = { 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4, @@ -28,12 +30,12 @@ int wasm::PopCount<uint8_t>(uint8_t v) { } template<> -int wasm::PopCount<uint16_t>(uint16_t v) { +int PopCount<uint16_t>(uint16_t v) { return PopCount((uint8_t)(v & 0xff)) + PopCount((uint8_t)(v >> 8)); } template<> -int wasm::PopCount<uint32_t>(uint32_t v) { +int PopCount<uint32_t>(uint32_t v) { // See Stanford bithacks, counting bits set in parallel, "best method": // http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel v = v - ((v >> 1) & 0x55555555); @@ -42,12 +44,12 @@ int wasm::PopCount<uint32_t>(uint32_t v) { } template<> -int wasm::PopCount<uint64_t>(uint64_t v) { +int PopCount<uint64_t>(uint64_t v) { return PopCount((uint32_t)v) + PopCount((uint32_t)(v >> 32)); } template<> -uint32_t wasm::BitReverse<uint32_t>(uint32_t v) { +uint32_t BitReverse<uint32_t>(uint32_t v) { // See Hacker's Delight, first edition, figure 7-1. v = ((v & 0x55555555) << 1) | ((v >> 1) & 0x55555555); v = ((v & 0x33333333) << 2) | ((v >> 2) & 0x33333333); @@ -57,7 +59,7 @@ uint32_t wasm::BitReverse<uint32_t>(uint32_t v) { } template<> -int wasm::CountTrailingZeroes<uint32_t>(uint32_t v) { +int CountTrailingZeroes<uint32_t>(uint32_t v) { // See Stanford bithacks, count the consecutive zero bits (trailing) on the // right with multiply and lookup: // http://graphics.stanford.edu/~seander/bithacks.html#ZerosOnRightMultLookup @@ -69,13 +71,13 @@ int wasm::CountTrailingZeroes<uint32_t>(uint32_t v) { } template<> -int wasm::CountTrailingZeroes<uint64_t>(uint64_t v) { +int CountTrailingZeroes<uint64_t>(uint64_t v) { return (uint32_t)v ? CountTrailingZeroes((uint32_t)v) : 32 + CountTrailingZeroes((uint32_t)(v >> 32)); } template<> -int wasm::CountLeadingZeroes<uint32_t>(uint32_t v) { +int CountLeadingZeroes<uint32_t>(uint32_t v) { // See Stanford bithacks, find the log base 2 of an N-bit integer in // O(lg(N)) operations with multiply and lookup: // http://graphics.stanford.edu/~seander/bithacks.html#IntegerLogDeBruijn @@ -92,7 +94,9 @@ int wasm::CountLeadingZeroes<uint32_t>(uint32_t v) { } template<> -int wasm::CountLeadingZeroes<uint64_t>(uint64_t v) { +int CountLeadingZeroes<uint64_t>(uint64_t v) { return v >> 32 ? CountLeadingZeroes((uint32_t)(v >> 32)) : 32 + CountLeadingZeroes((uint32_t)v); } + +} // namespace wasm |