# Function core::arch::riscv64::sm3p0

source · [−]

    pub fn sm3p0(x: u32) -> u32

🔬This is a nightly-only experimental API. (`stdsimd` #48556)
Available on RISC-V RV64 and target feature `zksh` only.
Expand description

`P0` transformation function as is used in the SM3 hash algorithm

This function is included in `Zksh` extension. It’s defined as:

    P0(X) = X ⊕ (X ≪ 9) ⊕ (X ≪ 17)

where `⊕` represents 32-bit xor, and `≪ k` represents rotate left by `k` bits.

In the SM3 algorithm, the `P0` transformation is used as `E ← P0(TT2)` when the compression function `CF` uses the intermediate value `TT2` to calculate the variable `E` in one iteration for subsequent processes.

According to RISC-V Cryptography Extensions, Volume I, the execution latency of this instruction must always be independent from the data it operates on.