java - Calculating Carry Flag -

i writing x86 interpreter in java , have python script tests implementations of x86 instructions against real counterparts using nasm. according test flags set correctly, besides carry flag. interesting part is:

long result;     switch (op) {     case add:         result = math.abs(x) + math.abs(y);         if (result > u_max)             registers.carry_flag = true;         else             registers.carry_flag = false;         break; 

where u_max 4294967295l (all 32 bits set).
answers found didn't realize carry , overflow 2 different things. so, how can implement carry flag correctly in java?

all absolute value business unnecessary , frankly confusing , has edge-case math.abs(integer.min_value) negative (not weird when down it, doesn't code expects it), can calculate carry in simpler ways .

for example using old "result unsigned less 1 operand". result of course x + y (as int), signedness irrelevant addition. java 8, can use integer.compareunsigned, otherwise can use identity:

x <u y = (x ^ integer.min_value) <s (y ^ integer.min_value) 

where <u , <s unsigned less , signed less than, respectively.

you calculate (x & 0xffffffffl) + (y & 0xffffffffl) , use both result (cast int) , carry flag (the 33th bit).