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chriselrodchriselrod
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add sorted method
1 parent 3d3e332 commit 8bb2b8c

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2 files changed

+94
-62
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2 files changed

+94
-62
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‎src/FindFirstFunctions.jl

Lines changed: 88 additions & 61 deletions
Original file line numberDiff line numberDiff line change
@@ -1,72 +1,99 @@
11
module FindFirstFunctions
22

3+
4+
function _findfirstequal(vpivot::Int64, ptr::Ptr{Int64}, len::Int64)
5+
Base.llvmcall(("""
6+
declare i8 @llvm.cttz.i8(i8, i1);
7+
define i64 @entry(i64 %0, i64 %1, i64 %2) #0 {
8+
top:
9+
%ivars = inttoptr i64 %1 to i64*
10+
%btmp = insertelement <8 x i64> undef, i64 %0, i64 0
11+
%var = shufflevector <8 x i64> %btmp, <8 x i64> undef, <8 x i32> zeroinitializer
12+
%lenm7 = add nsw i64 %2, -7
13+
%dosimditer = icmp ugt i64 %2, 7
14+
br i1 %dosimditer, label %L9.lr.ph, label %L32
15+
16+
L9.lr.ph:
17+
%len8 = and i64 %2, 9223372036854775800
18+
br label %L9
19+
20+
L9:
21+
%i = phi i64 [ 0, %L9.lr.ph ], [ %vinc, %L30 ]
22+
%ivarsi = getelementptr inbounds i64, i64* %ivars, i64 %i
23+
%vpvi = bitcast i64* %ivarsi to <8 x i64>*
24+
%v = load <8 x i64>, <8 x i64>* %vpvi, align 8
25+
%m = icmp eq <8 x i64> %v, %var
26+
%mu = bitcast <8 x i1> %m to i8
27+
%matchnotfound = icmp eq i8 %mu, 0
28+
br i1 %matchnotfound, label %L30, label %L17
29+
30+
L17:
31+
%tz8 = call i8 @llvm.cttz.i8(i8 %mu, i1 true)
32+
%tz64 = zext i8 %tz8 to i64
33+
%vis = add nuw i64 %i, %tz64
34+
br label %common.ret
35+
36+
common.ret:
37+
%retval = phi i64 [ %vis, %L17 ], [ -1, %L32 ], [ %si, %L51 ], [ -1, %L67 ]
38+
ret i64 %retval
39+
40+
L30:
41+
%vinc = add nuw nsw i64 %i, 8
42+
%continue = icmp slt i64 %vinc, %lenm7
43+
br i1 %continue, label %L9, label %L32
44+
45+
L32:
46+
%cumi = phi i64 [ 0, %top ], [ %len8, %L30 ]
47+
%done = icmp eq i64 %cumi, %2
48+
br i1 %done, label %common.ret, label %L51
49+
50+
L51:
51+
%si = phi i64 [ %inc, %L67 ], [ %cumi, %L32 ]
52+
%spi = getelementptr inbounds i64, i64* %ivars, i64 %si
53+
%svi = load i64, i64* %spi, align 8
54+
%match = icmp eq i64 %svi, %0
55+
br i1 %match, label %common.ret, label %L67
56+
57+
L67:
58+
%inc = add i64 %si, 1
59+
%dobreak = icmp eq i64 %inc, %2
60+
br i1 %dobreak, label %common.ret, label %L51
61+
62+
}
63+
attributes #0 = { alwaysinline }
64+
""", "entry"), Int64, Tuple{Int64,Ptr{Int64},Int64}, vpivot, ptr,
65+
len)
66+
end
67+
368
findfirstequal(vpivot, ivars) = findfirst(isequal(vpivot), ivars)
469
function findfirstequal(vpivot::Int64, ivars::DenseVector{Int64})
570
GC.@preserve ivars begin
6-
ret = Base.llvmcall(("""
7-
declare i8 @llvm.cttz.i8(i8, i1);
8-
define i64 @entry(i64 %0, i64 %1, i64 %2) #0 {
9-
top:
10-
%ivars = inttoptr i64 %1 to i64*
11-
%btmp = insertelement <8 x i64> undef, i64 %0, i64 0
12-
%var = shufflevector <8 x i64> %btmp, <8 x i64> undef, <8 x i32> zeroinitializer
13-
%lenm7 = add nsw i64 %2, -7
14-
%dosimditer = icmp ugt i64 %2, 7
15-
br i1 %dosimditer, label %L9.lr.ph, label %L32
16-
17-
L9.lr.ph:
18-
%len8 = and i64 %2, 9223372036854775800
19-
br label %L9
20-
21-
L9:
22-
%i = phi i64 [ 0, %L9.lr.ph ], [ %vinc, %L30 ]
23-
%ivarsi = getelementptr inbounds i64, i64* %ivars, i64 %i
24-
%vpvi = bitcast i64* %ivarsi to <8 x i64>*
25-
%v = load <8 x i64>, <8 x i64>* %vpvi, align 8
26-
%m = icmp eq <8 x i64> %v, %var
27-
%mu = bitcast <8 x i1> %m to i8
28-
%matchnotfound = icmp eq i8 %mu, 0
29-
br i1 %matchnotfound, label %L30, label %L17
30-
31-
L17:
32-
%tz8 = call i8 @llvm.cttz.i8(i8 %mu, i1 true)
33-
%tz64 = zext i8 %tz8 to i64
34-
%vis = add nuw i64 %i, %tz64
35-
br label %common.ret
36-
37-
common.ret:
38-
%retval = phi i64 [ %vis, %L17 ], [ -1, %L32 ], [ %si, %L51 ], [ -1, %L67 ]
39-
ret i64 %retval
40-
41-
L30:
42-
%vinc = add nuw nsw i64 %i, 8
43-
%continue = icmp slt i64 %vinc, %lenm7
44-
br i1 %continue, label %L9, label %L32
45-
46-
L32:
47-
%cumi = phi i64 [ 0, %top ], [ %len8, %L30 ]
48-
%done = icmp eq i64 %cumi, %2
49-
br i1 %done, label %common.ret, label %L51
50-
51-
L51:
52-
%si = phi i64 [ %inc, %L67 ], [ %cumi, %L32 ]
53-
%spi = getelementptr inbounds i64, i64* %ivars, i64 %si
54-
%svi = load i64, i64* %spi, align 8
55-
%match = icmp eq i64 %svi, %0
56-
br i1 %match, label %common.ret, label %L67
57-
58-
L67:
59-
%inc = add i64 %si, 1
60-
%dobreak = icmp eq i64 %inc, %2
61-
br i1 %dobreak, label %common.ret, label %L51
62-
63-
}
64-
attributes #0 = { alwaysinline }
65-
""", "entry"), Int64, Tuple{Int64,Ptr{Int64},Int64}, vpivot, pointer(ivars),
66-
length(ivars))
71+
ret = _findfirstequal(vpivot, pointer(ivars), length(ivars))
6772
end
6873
ret < 0 ? nothing : ret + 1
6974
end
7075

76+
"""
77+
findfirstsortedequal(vars::DenseVector{Int64}, var::Int64)::Union{Int64,Nothing}
78+
79+
Note that this differs from `searchsortedfirst` by returning `nothing` when absent.
80+
"""
81+
function findfirstsortedequal(var::Int64, vars::DenseVector{Int64},
82+
::Val{basecase}=Val(64)) where {basecase}
83+
len = length(vars)
84+
offset = 0
85+
@inbounds while len > basecase
86+
half = len >>> 1 # half on left, len - half on right
87+
offset = ifelse(vars[offset+half+1] <= var, half + offset, offset)
88+
len = len - half
89+
end
90+
# maybe occurs in vars[offset+1:offset+len]
91+
GC.@preserve vars begin
92+
ret = _findfirstequal(var, pointer(vars) + 8offset, len)
93+
end
94+
ret < 0 ? nothing : ret + offset + 1
95+
end
96+
97+
7198

7299
end

‎test/runtests.jl

Lines changed: 6 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -5,16 +5,21 @@ using Test
55

66
for n = 0:128
77
x = unique!(rand(Int, n))
8+
s = sort(x)
89
for i = eachindex(x)
910
@test FindFirstFunctions.findfirstequal(x[i], x) == i
11+
@test FindFirstFunctions.findfirstequal(s[i], s) == i
12+
@test FindFirstFunctions.findfirstsortedequal(s[i], s) == i
1013
end
1114
if length(x) > 0
1215
@test FindFirstFunctions.findfirstequal(x[begin], @view(x[begin:end])) === 1
1316
@test FindFirstFunctions.findfirstequal(x[begin], @view(x[begin+1:end])) === nothing
1417
@test FindFirstFunctions.findfirstequal(x[end], @view(x[begin:end-1])) === nothing
1518
end
1619
y = rand(Int)
17-
@test FindFirstFunctions.findfirstequal(y, x) === findfirst(==(y), x)
20+
ff = findfirst(==(y), x)
21+
@test FindFirstFunctions.findfirstequal(y, x) === ff
22+
ff === nothing && @test FindFirstFunctions.findfirstsortedequal(y, x) === nothing
1823
end
1924

2025
end

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