Optimize for LLVM 17

src/FindFirstFunctions.jl

@@ -83,22 +83,37 @@ end
 Note that this differs from `searchsortedfirst` by returning `nothing` when absent.
 """
 function findfirstsortedequal(var::Int64, vars::DenseVector{Int64},
- ::Val{basecase}=Val(128)) where {basecase}
+ ::Val{basecase}=Base.libllvm_version >= v"17" ? Val(8) : Val(128)) where {basecase}
  len = length(vars)
  offset = 0
  @inbounds while len > basecase
  half = len >>> 1 # half on left, len - half on right
- offset = ifelse(vars[offset+half+1] <= var, half + offset, offset)
+ if Base.libllvm_version >= v"17"
+ # TODO: check if this works
+ # I'm worried the `!unpredictable` metadata will be stripped
+ offset = Base.llvmcall(("""
+ define i64 @entry(i8 %0, i64 %1, i64 %2) #0 {
+ top:
+ %b = trunc i8 %0 to i1
+ %s = select i1 %b, i64 %1, i64 %2, !unpredictable !0
+ ret i64 %s
+ }
+ attributes #0 = { alwaysinline }
+ !0 = !{}
+ """, "entry"), Int64, Tuple{Bool,Int64,Int64}, vars[offset+half+1] <= var, half + offset, offset)
+ else
+ offset = ifelse(vars[offset+half+1] <= var, half + offset, offset)
+ end
  len = len - half
  end
  # maybe occurs in vars[offset+1:offset+len] 
  GC.@preserve vars begin
  ret = _findfirstequal(var, pointer(vars) + 8offset, len)
  end
+ # return ret 
  ret < 0 ? nothing : ret + offset + 1
 end
 
-
 """
  bracketstrictlymontonic(v, x, guess; lt=<comparison>, by=<transform>, rev=false)