# Function core::arch::x86_64::_mm_cvttss_si64

1.27.0 · source ·

    pub unsafe fn _mm_cvttss_si64(a: __m128) -> i64

Available on x86-64 and target feature `sse` only.
Expand description

Converts the lowest 32 bit float in the input vector to a 64 bit integer with truncation.

The result is rounded always using truncation (round towards zero). If the result cannot be represented as a 64 bit integer the result will be `0x8000_0000_0000_0000` (`i64::MIN`) or an invalid operation floating point exception if unmasked (see `_mm_setcsr`).

This corresponds to the `CVTTSS2SI` instruction (with 64 bit output).

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