admin管理员组

文章数量:1321248

For this code:

#include <stdfloat>

std::bfloat16_t foo(std::float32_t f)
{
    return f;
}

GCC generates this code:

foo(_Float32):
        sub     rsp, 8
        call    __truncsfbf2
        add     rsp, 8
        ret

Here we see call __truncsfbf2, which is (?) a software implementation (libgcc/soft-fp/truncsfbf2.c).

It is known that:

  • bfloat16 instructions are part of Intel DL Boost.
  • "DL Boost features were introduced in the Cascade Lake architecture."

Hence, when targeting Cascade Lake I expect to see Intel DL Boost bfloat16 instruction VCVT... (instead of call __truncsfbf2).

I've already tried to add -march=cascadelake. However, GCC still generates call __truncsfbf2.

Are there any GCC options to generate Intel DL Boost bfloat16 instructions?

The same question goes for Clang.

本文标签：

版权声明：本文标题：floating point - What are GCC and Clang options to generate Intel DL Boost bfloat16 instructions? - Stack Overflow 内容由网友自发贡献，该文观点仅代表作者本人， 转载请联系作者并注明出处：http://www.betaflare.com/web/1742097369a2420632.html， 本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如发现本站有涉嫌抄袭侵权/违法违规的内容，一经查实，本站将立刻删除。