uint2048& operator+=(uint2048& operand_a, uint64_t operand_b){
uint64_t a;
uint64_t* b;
uint8_t carry_flag = 0u;
a = operand_a.parts_[0u];
b = &(operand_a.parts_[0u]);
// intrinsic function
// adcx instruction
// *c = a + b + carry
// carry_flag is set to 1 if there is a carry bit
carry_flag = _addcarry_u64(carry_flag, a, operand_b, b);
if (carry_flag){
for (auto i = 1u; i < 32u; ++i){
a = operand_a.parts_[i];
b = &(operand_a.parts_[i]);
// intrinsic function
// adcx instruction
// *c = a + b + carry
carry_flag = _addcarry_u64(carry_flag, a, 0, b);
if (!carry_flag) break;
}
}
return operand_a;
}
static void
adx_test (void)
{
volatile unsigned char c;
unsigned long long x;
volatile unsigned long long y, sum_ref;
c = 0;
x = y = 0xFFFFFFFFFFFFFFFFLL;
sum_ref = 0xFFFFFFFFFFFFFFFELL;
/* X = 0xFFFFFFFFFFFFFFFF, Y = 0xFFFFFFFFFFFFFFFF, C = 0. */
c = _addcarryx_u64 (c, x, y, &x);
/* X = 0xFFFFFFFFFFFFFFFE, Y = 0xFFFFFFFFFFFFFFFF, C = 1. */
c = _addcarryx_u64 (c, x, y, &x);
/* X = 0xFFFFFFFFFFFFFFFE, Y = 0xFFFFFFFFFFFFFFFF, C = 1. */
if (x != sum_ref)
abort ();
c = 0;
x = y = 0xFFFFFFFFFFFFFFFFLL;
sum_ref = 0xFFFFFFFFFFFFFFFELL;
/* X = 0xFFFFFFFFFFFFFFFF, Y = 0xFFFFFFFFFFFFFFFF, C = 0. */
c = _addcarry_u64 (c, x, y, &x);
/* X = 0xFFFFFFFFFFFFFFFE, Y = 0xFFFFFFFFFFFFFFFF, C = 1. */
c = _addcarry_u64 (c, x, y, &x);
/* X = 0xFFFFFFFFFFFFFFFE, Y = 0xFFFFFFFFFFFFFFFF, C = 1. */
if (x != sum_ref)
abort ();
c = 0;
x = 1LL;
y = 0LL;
sum_ref = 0x0LL;
/* X = 0x0000000000000001, Y = 0x0000000000000000, C = 0. */
c = _subborrow_u64 (c, x, y, &x);
/* X = 0xFFFFFFFFFFFFFFFF, Y = 0x0000000000000000, C = 1. */
c = _subborrow_u64 (c, x, y, &x);
/* X = 0x0000000000000000, Y = 0x0000000000000000, C = 1. */
if (x != sum_ref)
abort ();
}
uint2048& operator+=(uint2048& operand_a, const uint2048& operand_b){
uint64_t a, b;
uint64_t* c;
uint8_t carry_flag = 0u;
for (auto i = 0u; i < 32u; ++i){
a = operand_a.parts_[i];
b = operand_b.parts_[i];
c = &(operand_a.parts_[i]);
// intrinsic function
// adcx instruction
// *c = a + b + carry
// carry_flag is set to 1 if there is a carry bit
carry_flag = _addcarry_u64(carry_flag, a, b, c);
}
return operand_a;
}
