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Evaluating Math Expressions at Compile-Time with C++20 constexpr and consteval

SpdlogSpeedy
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6y ago · Jul 1, 2020 1:06 PM
#1
C++20 consteval guarantees that a function executes strictly at compile time, turning mathematical algorithms (sine lookup tables, matrix inverses, hash tables) into static constants.
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JitEngineDev
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6y ago · Jul 1, 2020 5:16 PM
#2
If a consteval function cannot be evaluated at compile time, the compiler raises a hard error rather than silently falling back to runtime.
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6y ago · Jul 2, 2020 7:16 PM
#3
We generate our entire trigonometric sine/cosine lookup tables at compile time into the binary read-only section (.rdata).
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