- adds
int adds(int x, int y, bool overflow)
long adds(long x, long y, bool overflow)
cent adds(cent x, cent y, bool overflow)
Add two signed integers, checking for overflow.
- addu
uint addu(uint x, uint y, bool overflow)
ulong addu(ulong x, ulong y, bool overflow)
ucent addu(ucent x, ucent y, bool overflow)
Add two unsigned integers, checking for overflow (aka carry).
- muls
int muls(int x, int y, bool overflow)
long muls(long x, long y, bool overflow)
cent muls(cent x, cent y, bool overflow)
Multiply two signed integers, checking for overflow.
- mulu
uint mulu(uint x, uint y, bool overflow)
ulong mulu(ulong x, uint y, bool overflow)
ulong mulu(ulong x, ulong y, bool overflow)
ucent mulu(ucent x, ucent y, bool overflow)
Multiply two unsigned integers, checking for overflow (aka carry).
- negs
int negs(int x, bool overflow)
long negs(long x, bool overflow)
cent negs(cent x, bool overflow)
- subs
int subs(int x, int y, bool overflow)
long subs(long x, long y, bool overflow)
cent subs(cent x, cent y, bool overflow)
Subtract two signed integers, checking for overflow.
- subu
uint subu(uint x, uint y, bool overflow)
ulong subu(ulong x, ulong y, bool overflow)
ucent subu(ucent x, ucent y, bool overflow)
Subtract two unsigned integers, checking for overflow (aka borrow).
This module implements integral arithmetic primitives that check for out-of-range results.
Integral arithmetic operators operate on fixed width types. Results that are not representable in those fixed widths are silently truncated to fit. This module offers integral arithmetic primitives that produce the same results, but set an 'overflow' flag when such truncation occurs. The setting is sticky, meaning that numerous operations can be cascaded and then the flag need only be checked at the end. Whether the operation is signed or unsigned is indicated by an 's' or 'u' suffix, respectively. While this could be achieved without such suffixes by using overloading on the signedness of the types, the suffix makes it clear which is happening without needing to examine the types.
While the generic versions of these functions are computationally expensive relative to the cost of the operation itself, compiler implementations are free to recognize them and generate equivalent and faster code.
The functions here are templates so they can be used with -betterC, as betterC does not link with this library.
References: Fast Integer Overflow Checks