Add additional path for x64 MSVC intrinsics

Author: mborland

include/boost/decimal/detail/u128.hpp

@@ -1956,6 +1956,13 @@ BOOST_DECIMAL_FORCE_INLINE constexpr void div_mod_impl(const u128& lhs, const u1
 
         remainder.high = UINT64_C(0);
     }
+    #ifdef BOOST_DECIMAL_HAS_MSVC_X64_INTRINSICS
+    else if (rhs.high == UINT64_C(0))
+    {
+        // Since low is at least 2^32 the quotient will be less than 2^64
+        quotient.low = _udiv128(lhs.high, lhs.low, rhs.low, &remainder.low);
+    }
+    #endif
     else
     {
         auto lhs_wide = u128_to_wide_integer(lhs);

test/benchmark_uints.cpp

@@ -389,11 +389,11 @@ int main()
         std::cout << std::endl;
 
         #if defined(BOOST_DECIMAL_HAS_INT128) || defined(BOOST_DECIMAL_HAS_MSVC_INTERNAL_U128)
-        test_digit_counting(builtin_vector, "builtin");
+        // test_digit_counting(builtin_vector, "builtin");
         #endif
 
-        test_digit_counting(old_vector, "old");
-        test_digit_counting(new_vector, "new");
+        // test_digit_counting(old_vector, "old");
+        // test_digit_counting(new_vector, "new");
     }
     // Single word operations
     {
@@ -451,11 +451,11 @@ int main()
         std::cout << std::endl;
 
         #if defined(BOOST_DECIMAL_HAS_INT128) || defined(BOOST_DECIMAL_HAS_MSVC_INTERNAL_U128)
-        test_digit_counting(builtin_vector, "builtin");
+        // test_digit_counting(builtin_vector, "builtin");
         #endif
 
-        test_digit_counting(old_vector, "old");
-        test_digit_counting(new_vector, "new");
+        // test_digit_counting(old_vector, "old");
+        // test_digit_counting(new_vector, "new");
     }
     {
         // Two word and one word operations Even = 2, odd = 1
@@ -514,11 +514,11 @@ int main()
         std::cout << std::endl;
 
         #if defined(BOOST_DECIMAL_HAS_INT128) || defined(BOOST_DECIMAL_HAS_MSVC_INTERNAL_U128)
-        test_digit_counting(builtin_vector, "builtin");
+        // test_digit_counting(builtin_vector, "builtin");
         #endif
 
-        test_digit_counting(old_vector, "old");
-        test_digit_counting(new_vector, "new");
+        // test_digit_counting(old_vector, "old");
+        // test_digit_counting(new_vector, "new");
     }
     {
         // Two word and one word operations Even = 1, odd = 2
@@ -577,11 +577,11 @@ int main()
         std::cout << std::endl;
 
         #if defined(BOOST_DECIMAL_HAS_INT128) || defined(BOOST_DECIMAL_HAS_MSVC_INTERNAL_U128)
-        test_digit_counting(builtin_vector, "builtin");
+        // test_digit_counting(builtin_vector, "builtin");
         #endif
 
-        test_digit_counting(old_vector, "old");
-        test_digit_counting(new_vector, "new");
+        // test_digit_counting(old_vector, "old");
+        // test_digit_counting(new_vector, "new");
     }
     {
         // Two word and one word operations Even = 1, odd = 2
@@ -649,11 +649,11 @@ int main()
         std::cout << std::endl;
 
         #if defined(BOOST_DECIMAL_HAS_INT128) || defined(BOOST_DECIMAL_HAS_MSVC_INTERNAL_U128)
-        test_digit_counting(builtin_vector, "builtin");
+        // test_digit_counting(builtin_vector, "builtin");
         #endif
 
-        test_digit_counting(old_vector, "old");
-        test_digit_counting(new_vector, "new");
+        // test_digit_counting(old_vector, "old");
+        // test_digit_counting(new_vector, "new");
     }
 
     return 1;