h2log2

Applicability

Function Usage

Obtains the logarithm of each element in the input data with base 2.

Prototype

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inline half2 h2log2(half2 x)

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inline bfloat16x2_t h2log2(bfloat16x2_t x)

Parameters

Returns

Logarithm of each element in the input data with base 2.

• If the input element is less than 0 or is nan, the return value is nan.
• If the input element is 0, the return value is -inf.
• If the input element is inf, the return value is inf.

Restrictions

For SIMT programming, this API is not supported.

Header File to Be Included

To use the half2 API, the simt_api/asc_fp16.h header file must be included. To use the bfloat16x2_t API, the simt_api/asc_bf16.h header file must be included.

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#include "simt_api/asc_fp16.h"

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#include "simt_api/asc_bf16.h"

Examples

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__simt_vf__ __launch_bounds__(1024) inline void KernelLog2(__gm__ half2* dst, __gm__ half2* x)
{
    int idx = threadIdx.x + blockIdx.x * blockDim.x;
    dst[idx] = h2log2(x[idx]);
}