1 //===--- RustDemangle.cpp ---------------------------------------*- C++ -*-===//
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
10 // https://rust-lang.github.io/rfcs/2603-rust-symbol-name-mangling-v0.html
12 //===----------------------------------------------------------------------===//
180 /// Returns true if C is a valid mangled character: <0-9a-zA-Z_>.
189 // <symbol-name> = "_R" <path> [<instantiating-crate>]
230 //        | "M" <impl-path> <type>         // <T> (inherent impl)
231 //        | "X" <impl-path> <type> <path>  // <T as Trait> (trait impl)
234 //        | "I" <path> {<generic-arg>} "E" // ...<T, U> (generic args)
236 // <identifier> = [<disambiguator>] <undisambiguated-identifier>
239 //      | <A-Z>    // other special namespaces
240 //      | <a-z>    // internal namespaces
344 // <impl-path> = [<disambiguator>] <path>
345 // <disambiguator> = "s" <base-62-number>
352 // <generic-arg> = <lifetime>
355 // <lifetime> = "L" <base-62-number>
365 // <basic-type> = "a"      // i8
524 // <type> = | <basic-type>
533 //          | "F" <fn-sig>                // fn(...) -> ...
534 //          | "D" <dyn-bounds> <lifetime> // dyn Trait<Assoc = X> + Send + 'a
620 // <fn-sig> := [<binder>] ["U"] ["K" <abi>] {<type>} "E" <type>
622 //       | <undisambiguated-identifier>
639         // When mangling ABI string, the "-" is replaced with "_".  in demangleFnSig()
641           C = '-';  in demangleFnSig()
659     print(" -> ");  in demangleFnSig()
664 // <dyn-bounds> = [<binder>] {<dyn-trait>} "E"
676 // <dyn-trait> = <path> {<dyn-trait-assoc-binding>}
677 // <dyn-trait-assoc-binding> = "p" <undisambiguated-identifier> <type>
697 // <binder> = "G" <base-62-number>
707   if (Binder >= Input.size() - BoundLifetimes) {  in demangleOptionalBinder()
722 // <const> = <basic-type> <const-data>
770 // <const-data> = ["n"] <hex-number>
773     print('-');  in demangleConstInt()
785 // <const-data> = "0_" // false
803 // <const-data> = <hex-number>
846 // <undisambiguated-identifier> = ["u"] <decimal-number> ["_"] <bytes>
855   if (Error || Bytes > Input.size() - Position) {  in parseIdentifier()
888 // Parses base 62 number with <0-9a-zA-Z> as digits. Number is terminated by
892 // <base-62-number> = {<0-9a-zA-Z>} "_"
906       Digit = C - '0';  in parseBase62Number()
908       Digit = 10 + (C - 'a');  in parseBase62Number()
910       Digit = 10 + 26 + (C - 'A');  in parseBase62Number()
931 // <decimal-number> = "0"
932 //                  | <1-9> {<0-9>}
953     uint64_t D = consume() - '0';  in parseDecimalNumber()
961 // Parses a hexadecimal number with <0-9a-f> as a digits. Returns the parsed
965 // <hex-number> = "0_"
966 //              | <1-9a-f> {<0-9a-f>} "_"
982         Value += C - '0';  in parseHexNumber()
984         Value += 10 + (C - 'a');  in parseHexNumber()
995   size_t End = Position - 1;  in parseHexNumber()
997   HexDigits = Input.substr(Start, End - Start);  in parseHexNumber()
1023 // starting from 1, are De Bruijn indices, referring to higher-ranked lifetimes
1031   if (Index - 1 >= BoundLifetimes) {  in printLifetime()
1036   uint64_t Depth = BoundLifetimes - Index;  in printLifetime()
1043     printDecimalNumber(Depth - 26 + 1);  in printLifetime()
1049     Value = C - 'a';  in decodePunycodeDigit()
1054     Value = 26 + (C - '0');  in decodePunycodeDigit()
1065   Output.setCurrentPosition(std::remove(Start, End, '\0') - Buffer);  in removeNullBytes()
1068 // Encodes code point as UTF-8 and stores results in Output. Returns false if
1130   size_t Skew = 38;  in decodePunycode()  local
1143     while (Delta > (Base - TMin) * TMax / 2) {  in decodePunycode()
1144       Delta /= Base - TMin;  in decodePunycode()
1147     return K + (((Base - TMin + 1) * Delta) / (Delta + Skew));  in decodePunycode()
1163       if (Digit > (Max - I) / W)  in decodePunycode()
1173         T = K - Bias;  in decodePunycode()
1178       if (W > Max / (Base - T))  in decodePunycode()
1180       W *= (Base - T);  in decodePunycode()
1182     size_t NumPoints = (Output.getCurrentPosition() - OutputSize) / 4 + 1;  in decodePunycode()
1183     Bias = Adapt(I - OldI, NumPoints);  in decodePunycode()
1185     if (I / NumPoints > Max - N)  in decodePunycode()
1240   if (A > std::numeric_limits<uint64_t>::max() - B) {  in addAssign()