Update based on review comments

base/sysimg.jl

@@ -87,12 +87,12 @@ include("osutils.jl")
 include("utferror.jl")
 include("utftype.jl")
 include("utfcheck.jl")
+include("utfconvert.jl")
 include("char.jl")
 include("ascii.jl")
 include("utf8.jl")
 include("utf16.jl")
 include("utf32.jl")
-include("utfconvert.jl")
 include("iobuffer.jl")
 include("string.jl")
 include("utf8proc.jl")

base/utf16.jl

@@ -74,12 +74,6 @@ end
 unsafe_convert{T<:Union(Int16,UInt16)}(::Type{Ptr{T}}, s::UTF16String) =
     convert(Ptr{T}, pointer(s))
 
-function convert(::Type{UTF16String}, data::AbstractVector{UInt16})
-    !isvalid(UTF16String, data) && throw(ArgumentError("invalid UTF16 data"))
-    len = length(data)
-    @inbounds return UTF16String(setindex!(copy!(Vector{UInt16}(len+1),1,data,1,len),0,len+1))
-end
-
 convert(T::Type{UTF16String}, data::AbstractArray{UInt16}) =
     convert(T, reshape(data, length(data)))
 

base/utf32.jl

@@ -9,11 +9,6 @@ reverse(s::UTF32String) = UTF32String(reverse!(copy(s.data), 1, length(s)))
 
 sizeof(s::UTF32String) = sizeof(s.data) - sizeof(Char)
 
-function convert(::Type{UTF32String}, data::AbstractVector{Char})
-    len = length(data)
-    @inbounds return UTF32String(setindex!(copy!(Vector{Char}(len+1),1,data,1,len),0,len+1))
-end
-
 convert{T<:Union(Int32,UInt32)}(::Type{UTF32String}, data::AbstractVector{T}) =
     convert(UTF32String, reinterpret(Char, data))
 
@@ -45,7 +40,9 @@ function convert(T::Type{UTF32String}, bytes::AbstractArray{UInt8})
         copy!(d,1, data, 2, length(data)-1)
     elseif data[1] == Char(0xfffe0000) # byte-swapped
         d = Array(Char, length(data))
-        @inbounds for i = 2:length(data) ; d[i-1] = bswap(data[i]) ; end
+        for i = 2:length(data)
+            @inbounds d[i-1] = bswap(data[i])
+        end
     else
         d = Array(Char, length(data) + 1)
         copy!(d, 1, data, 1, length(data)) # assume native byte order

base/utfconvert.jl

@@ -3,28 +3,25 @@
 # Functions to convert to different UTF encodings
 
 # Quickly copy and set trailing \0
-@inline function fast_utf_copy(T::Type{UInt16}, len, dat)
-    @inbounds return UTF16String(setindex!(copy!(Vector{T}(len), dat), 0, len))
-end
-@inline function fast_utf_copy(T::Type{Char}, len, dat)
-    @inbounds return UTF32String(setindex!(copy!(Vector{T}(len), dat), 0, len))
+@inline function fast_utf_copy{S <: Union(UTF16String, UTF32String), T <: Union(UInt16, Char)}(::Type{S}, ::Type{T}, len, dat, flag::Bool=false)
+     @inbounds return flag ? S(setindex!(copy!(Vector{T}(len+1),1,dat,1,len),0,len+1)) : S(setindex!(copy!(Vector{T}(len), dat), 0, len))
 end
 
 # Get rest of character ch from 3-byte UTF-8 sequence in dat
-@inline function get_utf8_3(dat, pos, ch)
+@inline function get_utf8_3byte(dat, pos, ch)
     @inbounds return ((ch & 0xf) << 12) | (UInt32(dat[pos-1] & 0x3f) << 6) | (dat[pos] & 0x3f)
 end
 
 # Get rest of character ch from 4-byte UTF-8 sequence in dat
-@inline function get_utf8_4(dat, pos, ch)
+@inline function get_utf8_4byte(dat, pos, ch)
     @inbounds return (((ch & 0x7) << 18)
                         | (UInt32(dat[pos-2] & 0x3f) << 12)
                         | (UInt32(dat[pos-1] & 0x3f) << 6)
                         | (dat[pos] & 0x3f))
 end
 
 # Output a character as a 4-byte UTF-8 sequence
-@inline function output_utf8_4(buf, out, ch)
+@inline function output_utf8_4byte!(buf, out, ch)
     @inbounds begin
         buf[out + 1] = 0xf0 | (ch >>> 18)
         buf[out + 2] = 0x80 | ((ch >>> 12) & 0x3f)
@@ -117,11 +114,11 @@ function convert(::Type{UTF16String}, str::UTF8String)
         # Handle range 0x800-0xffff
         elseif ch < 0xf0
             pos += 2
-            buf[out += 1] = get_utf8_3(dat, pos, ch)
+            buf[out += 1] = get_utf8_3byte(dat, pos, ch)
         # Handle range 0x10000-0x10ffff
         else
             pos += 3
-            ch = get_utf8_4(dat, pos, ch)
+            ch = get_utf8_4byte(dat, pos, ch)
             # output surrogate pair
             buf[out += 1] = UInt16(0xd7c0 + (ch >>> 10))
             buf[out += 1] = UInt16(0xdc00 + (ch & 0x3ff))
@@ -241,12 +238,12 @@ function encode_to_utf8{T<:Union(UInt16, UInt32)}(::Type{T}, dat, len)
             buf[out += 1] = 0xc0 | (ch >>> 6)
             buf[out += 1] = 0x80 | (ch & 0x3f)
         # Handle 0x10000-0x10ffff (if input is UInt32)
-        elseif T == UInt32 && ch > 0xffff
-            output_utf8_4(buf, out, ch)
+        elseif ch > 0xffff # this is only for T == UInt32, should not be generated for UInt16
+            output_utf8_4byte!(buf, out, ch)
             out += 4
         # Handle surrogate pairs
         elseif is_surrogate_codeunit(ch)
-            output_utf8_4(buf, out, get_supplementary(ch, dat[pos += 1]))
+            output_utf8_4byte!(buf, out, get_supplementary(ch, dat[pos += 1]))
             out += 4
         # Handle 0x800-0xd7ff, 0xe000-0xffff UCS-2 characters
         else
@@ -277,7 +274,7 @@ function convert(::Type{UTF32String}, str::UTF8String)
     len, flags = check_string_utf8(dat)
     # Optimize case where no characters > 0x7f
     totlen = len+1
-    flags == 0 && return fast_utf_copy(Char, totlen, dat)
+    flags == 0 && return fast_utf_copy(UTF32String, Char, totlen, dat)
     # has multi-byte UTF-8 sequences
     buf = Vector{Char}(totlen)
     @inbounds buf[totlen] = 0 # NULL termination
@@ -295,7 +292,7 @@ function convert(::Type{UTF32String}, str::UTF8String)
         # Handle range 0x800-0xffff
         elseif ch < 0xf0
             pos += 2
-            ch = get_utf8_3(dat, pos, ch)
+            ch = get_utf8_3byte(dat, pos, ch)
             # Handle surrogate pairs (should have been encoded in 4 bytes)
             if is_surrogate_lead(ch)
                 # Build up 32-bit character from ch and trailing surrogate in next 3 bytes
@@ -309,7 +306,7 @@ function convert(::Type{UTF32String}, str::UTF8String)
         # Handle range 0x10000-0x10ffff
         else
             pos += 3
-            buf[out += 1] = get_utf8_4(dat, pos, ch)
+            buf[out += 1] = get_utf8_4byte(dat, pos, ch)
         end
     end
     UTF32String(buf)
@@ -367,7 +364,7 @@ function convert(::Type{UTF16String}, dat::Vector{UInt32})
     len, flags, num4byte = check_string_utf32(dat, len>>>2)
     len += num4byte + 1
     # optimized path, no surrogates
-    num4byte == 0 && return fast_utf_copy(UInt16, len, dat)
+    num4byte == 0 && return fast_utf_copy(UTF16String, UInt16, len, dat)
     return encode_to_utf16(dat, len)
 end
 
@@ -423,22 +420,31 @@ end
 
 convert(::Type{UTF8String},  dat::Vector{Char})   = convert(UTF8String, reinterpret(UInt32, dat))
 
+convert(::Type{UTF16String}, str::UTF16String)    = str
+convert(::Type{UTF16String}, dat::Vector{Char})   = convert(UTF16String, reinterpret(UInt32, dat))
+
 function convert(::Type{UTF16String}, str::ASCIIString)
     dat = str.data
-    fast_utf_copy(UInt16, length(dat)+1, dat)
+    fast_utf_copy(UTF16String, UInt16, length(dat)+1, dat)
 end
 
-function convert(::Type{UTF32String}, str::ASCIIString)
-    dat = str.data
-    fast_utf_copy(Char, length(dat)+1, dat)
+function convert(::Type{UTF16String}, data::AbstractVector{UInt16})
+    !isvalid(UTF16String, data) && throw(ArgumentError("invalid UTF16 data"))
+    fast_utf_copy(UTF16String, UInt16, length(data), data, true)
 end
 
-convert(::Type{UTF16String}, str::UTF16String)    = str
-convert(::Type{UTF16String}, dat::Vector{Char})   = convert(UTF16String, reinterpret(UInt32, dat))
-
 convert(::Type{Vector{UInt16}}, str::UTF16String) = str.data
 convert(::Type{Array{UInt16}},  str::UTF16String) = str.data
 
 convert(::Type{UTF32String}, str::UTF32String)    = str
 
 convert(::Type{UTF32String}, c::Char)             = UTF32String(Char[c, Char(0)])
+
+function convert(::Type{UTF32String}, str::ASCIIString)
+    dat = str.data
+    fast_utf_copy(UTF32String, Char, length(dat)+1, dat)
+end
+
+convert(::Type{UTF32String}, dat::AbstractVector{Char}) = fast_utf_copy(UTF32String, Char, length(dat), dat, true)
+
+

base/utferror.jl

@@ -43,7 +43,7 @@ const errMsgs = [
 @throws never returns, always throws ArgumentError
 """ ->
 =#
-function utf_errfunc(errcode::Integer, charpos, invchar)
+@noinline function utf_errfunc(errcode::Integer, charpos, invchar)
     if errcode < 1 || errcode > UTF_ERR_MAX
         throw(ArgumentError("Invalid error code for Unicode error: $errcode, Pos = $charpos, Char = $invchar"))
     end