CheckedArithmetic.h File Reference

Overflow-checked integer arithmetic for GPU byte-size and extent math. More...

#include <cstdint>
#include <optional>

Include dependency graph for CheckedArithmetic.h:

Namespaces
namespace	donner
	Top-level Donner namespace, which is split into different sub-namespaces such as donner::svg and donner::css.

Functions
std::optional< uint64_t >	donner::gpu::CheckedAdd (uint64_t a, uint64_t b)
	Overflow-checked addition of unsigned 64-bit sizes.
std::optional< uint64_t >	donner::gpu::CheckedMul (uint64_t a, uint64_t b)
	Overflow-checked multiplication of unsigned 64-bit sizes.

Detailed Description

Overflow-checked integer arithmetic for GPU byte-size and extent math.

Function Documentation

CheckedAdd()

std::optional< uint64_t > donner::gpu::CheckedAdd ( uint64_t a, uint64_t b )

inline

Overflow-checked addition of unsigned 64-bit sizes.

All byte-size and extent arithmetic in the GPU runtime is checked (design 0053 "Security and Reliability"): untrusted SVG content controls geometry volume and image sizes, so silent wraparound must be impossible.

Parameters

a	First operand.
b	Second operand.

Returns

The sum, or std::nullopt on overflow.

CheckedMul()

std::optional< uint64_t > donner::gpu::CheckedMul ( uint64_t a, uint64_t b )

inline

Overflow-checked multiplication of unsigned 64-bit sizes.

Parameters

a	First operand.
b	Second operand.

Returns

The product, or std::nullopt on overflow.