Skip to content

_mm_adds_epu8 doesn't generate the right instruction. #2154

@ruriww

Description

@ruriww

https://godbolt.org/z/KTTPcKP58

#[target_feature(enable = "sse2")]
pub fn simd_gte2(x: __m128i) -> i32 {
  let bc = _mm_set1_epi8(0x7e);
  let y = _mm_adds_epu8(x, bc);
  
   _mm_movemask_epi8(y)
}
.LCPI0_0:
        .zero   16,2
example::simd_gte2:
        movdqa  xmm0, xmmword ptr [rdi]
        movdqa  xmm1, xmmword ptr [rip + .LCPI0_0]
        pmaxub  xmm1, xmm0 ; 1
        pcmpeqb xmm1, xmm0 ; 2: these two instructions can be simplified to paddusb
        pmovmskb        eax, xmm1
        ret

Metadata

Metadata

Assignees

No one assigned

    Labels

    No labels
    No labels

    Type

    No type
    No fields configured for issues without a type.

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions