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authorFernando Sahmkow <fsahmkow27@gmail.com>2019-02-16 16:52:24 -0400
committerFernando Sahmkow <fsahmkow27@gmail.com>2019-02-16 16:52:24 -0400
commitf28935f37da1eb508a7d17c4c808f9a69293dc42 (patch)
treea5b08502c0fce93f8ef7a429ae873571eca1f852 /src/common/uint128.cpp
parent435c39e867fe1f7518349a20f039a8b3f0223d4d (diff)
Corrections, documenting and fixes.
Diffstat (limited to 'src/common/uint128.cpp')
-rw-r--r--src/common/uint128.cpp11
1 files changed, 6 insertions, 5 deletions
diff --git a/src/common/uint128.cpp b/src/common/uint128.cpp
index 8548ba8085..2238a52c53 100644
--- a/src/common/uint128.cpp
+++ b/src/common/uint128.cpp
@@ -3,31 +3,32 @@
#pragma intrinsic(_umul128)
#endif
+#include <cstring>
#include "common/uint128.h"
namespace Common {
+
u128 Multiply64Into128(u64 a, u64 b) {
-#ifdef _MSC_VER
u128 result;
+#ifdef _MSC_VER
result[0] = _umul128(a, b, &result[1]);
#else
unsigned __int128 tmp = a;
tmp *= b;
- u128 result;
std::memcpy(&result, &tmp, sizeof(u128));
#endif
return result;
}
-std::pair<u64, u64> Divide128On64(u128 dividend, u64 divisor) {
+std::pair<u64, u64> Divide128On32(u128 dividend, u32 divisor) {
u64 remainder = dividend[0] % divisor;
u64 accum = dividend[0] / divisor;
if (dividend[1] == 0)
return {accum, remainder};
// We ignore dividend[1] / divisor as that overflows
- u64 first_segment = (dividend[1] % divisor) << 32;
+ const u64 first_segment = (dividend[1] % divisor) << 32;
accum += (first_segment / divisor) << 32;
- u64 second_segment = (first_segment % divisor) << 32;
+ const u64 second_segment = (first_segment % divisor) << 32;
accum += (second_segment / divisor);
remainder += second_segment % divisor;
if (remainder >= divisor) {