X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2FStringRef.h;h=cd846031c5a02030e0b269033e89b51e32955fff;hb=58aae3841cb054e909d6b5251399bfd7478653bc;hp=1766d2b9f2d017f78346292a1773f13c7f6992d7;hpb=63c133b67d61b0c457ff46c957aed2b8d90b599c;p=oota-llvm.git diff --git a/include/llvm/ADT/StringRef.h b/include/llvm/ADT/StringRef.h index 1766d2b9f2d..cd846031c5a 100644 --- a/include/llvm/ADT/StringRef.h +++ b/include/llvm/ADT/StringRef.h @@ -10,15 +10,27 @@ #ifndef LLVM_ADT_STRINGREF_H #define LLVM_ADT_STRINGREF_H +#include "llvm/Support/type_traits.h" + +#include #include #include -#include +#include #include +#include namespace llvm { template class SmallVectorImpl; class APInt; + class hash_code; + class StringRef; + + /// Helper functions for StringRef::getAsInteger. + bool getAsUnsignedInteger(StringRef Str, unsigned Radix, + unsigned long long &Result); + + bool getAsSignedInteger(StringRef Str, unsigned Radix, long long &Result); /// StringRef - Represent a constant reference to a string, i.e. a character /// array and a length, which need not be null terminated. @@ -46,7 +58,14 @@ namespace llvm { // integer works around this bug. static size_t min(size_t a, size_t b) { return a < b ? a : b; } static size_t max(size_t a, size_t b) { return a > b ? a : b; } - + + // Workaround memcmp issue with null pointers (undefined behavior) + // by providing a specialized version + static int compareMemory(const char *Lhs, const char *Rhs, size_t Length) { + if (Length == 0) { return 0; } + return ::memcmp(Lhs,Rhs,Length); + } + public: /// @name Constructors /// @{ @@ -56,11 +75,17 @@ namespace llvm { /// Construct a string ref from a cstring. /*implicit*/ StringRef(const char *Str) - : Data(Str), Length(::strlen(Str)) {} + : Data(Str) { + assert(Str && "StringRef cannot be built from a NULL argument"); + Length = ::strlen(Str); // invoking strlen(NULL) is undefined behavior + } /// Construct a string ref from a pointer and length. /*implicit*/ StringRef(const char *data, size_t length) - : Data(data), Length(length) {} + : Data(data), Length(length) { + assert((data || length == 0) && + "StringRef cannot be built from a NULL argument with non-null length"); + } /// Construct a string ref from an std::string. /*implicit*/ StringRef(const std::string &Str) @@ -104,7 +129,7 @@ namespace llvm { /// compare() when the relative ordering of inequal strings isn't needed. bool equals(StringRef RHS) const { return (Length == RHS.Length && - memcmp(Data, RHS.Data, RHS.Length) == 0); + compareMemory(Data, RHS.Data, RHS.Length) == 0); } /// equals_lower - Check for string equality, ignoring case. @@ -116,7 +141,7 @@ namespace llvm { /// is lexicographically less than, equal to, or greater than the \arg RHS. int compare(StringRef RHS) const { // Check the prefix for a mismatch. - if (int Res = memcmp(Data, RHS.Data, min(Length, RHS.Length))) + if (int Res = compareMemory(Data, RHS.Data, min(Length, RHS.Length))) return Res < 0 ? -1 : 1; // Otherwise the prefixes match, so we only need to check the lengths. @@ -183,13 +208,13 @@ namespace llvm { /// startswith - Check if this string starts with the given \arg Prefix. bool startswith(StringRef Prefix) const { return Length >= Prefix.Length && - memcmp(Data, Prefix.Data, Prefix.Length) == 0; + compareMemory(Data, Prefix.Data, Prefix.Length) == 0; } /// endswith - Check if this string ends with the given \arg Suffix. bool endswith(StringRef Suffix) const { return Length >= Suffix.Length && - memcmp(end() - Suffix.Length, Suffix.Data, Suffix.Length) == 0; + compareMemory(end() - Suffix.Length, Suffix.Data, Suffix.Length) == 0; } /// @} @@ -268,6 +293,16 @@ namespace llvm { /// Note: O(size() + Chars.size()) size_type find_last_of(StringRef Chars, size_t From = npos) const; + /// find_last_not_of - Find the last character in the string that is not + /// \arg C, or npos if not found. + size_type find_last_not_of(char C, size_t From = npos) const; + + /// find_last_not_of - Find the last character in the string that is not in + /// \arg Chars, or npos if not found. + /// + /// Note: O(size() + Chars.size()) + size_type find_last_not_of(StringRef Chars, size_t From = npos) const; + /// @} /// @name Helpful Algorithms /// @{ @@ -291,14 +326,29 @@ namespace llvm { /// /// If the string is invalid or if only a subset of the string is valid, /// this returns true to signify the error. The string is considered - /// erroneous if empty. + /// erroneous if empty or if it overflows T. /// - bool getAsInteger(unsigned Radix, long long &Result) const; - bool getAsInteger(unsigned Radix, unsigned long long &Result) const; - bool getAsInteger(unsigned Radix, int &Result) const; - bool getAsInteger(unsigned Radix, unsigned &Result) const; + template + typename enable_if_c::is_signed, bool>::type + getAsInteger(unsigned Radix, T &Result) const { + long long LLVal; + if (getAsSignedInteger(*this, Radix, LLVal) || + static_cast(LLVal) != LLVal) + return true; + Result = LLVal; + return false; + } - // TODO: Provide overloads for int/unsigned that check for overflow. + template + typename enable_if_c::is_signed, bool>::type + getAsInteger(unsigned Radix, T &Result) const { + unsigned long long ULLVal; + if (getAsUnsignedInteger(*this, Radix, ULLVal) || + static_cast(ULLVal) != ULLVal) + return true; + Result = ULLVal; + return false; + } /// getAsInteger - Parse the current string as an integer of the /// specified radix, or of an autosensed radix if the radix given @@ -313,6 +363,16 @@ namespace llvm { /// string is well-formed in the given radix. bool getAsInteger(unsigned Radix, APInt &Result) const; + /// @} + /// @name String Operations + /// @{ + + // lower - Convert the given ASCII string to lowercase. + std::string lower() const; + + /// upper - Convert the given ASCII string to uppercase. + std::string upper() const; + /// @} /// @name Substring Operations /// @{ @@ -330,6 +390,20 @@ namespace llvm { Start = min(Start, Length); return StringRef(Data + Start, min(N, Length - Start)); } + + /// drop_front - Return a StringRef equal to 'this' but with the first + /// elements dropped. + StringRef drop_front(unsigned N = 1) const { + assert(size() >= N && "Dropping more elements than exist"); + return substr(N); + } + + /// drop_back - Return a StringRef equal to 'this' but with the last + /// elements dropped. + StringRef drop_back(unsigned N = 1) const { + assert(size() >= N && "Dropping more elements than exist"); + return substr(0, size()-N); + } /// slice - Return a reference to the substring from [Start, End). /// @@ -417,6 +491,24 @@ namespace llvm { return std::make_pair(slice(0, Idx), slice(Idx+1, npos)); } + /// ltrim - Return string with consecutive characters in \arg Chars starting + /// from the left removed. + StringRef ltrim(StringRef Chars = " \t\n\v\f\r") const { + return drop_front(std::min(Length, find_first_not_of(Chars))); + } + + /// rtrim - Return string with consecutive characters in \arg Chars starting + /// from the right removed. + StringRef rtrim(StringRef Chars = " \t\n\v\f\r") const { + return drop_back(Length - std::min(Length, find_last_not_of(Chars) + 1)); + } + + /// trim - Return string with consecutive characters in \arg Chars starting + /// from the left and right removed. + StringRef trim(StringRef Chars = " \t\n\v\f\r") const { + return ltrim(Chars).rtrim(Chars); + } + /// @} }; @@ -447,8 +539,15 @@ namespace llvm { return LHS.compare(RHS) != -1; } + inline std::string &operator+=(std::string &buffer, llvm::StringRef string) { + return buffer.append(string.data(), string.size()); + } + /// @} + /// \brief Compute a hash_code for a StringRef. + hash_code hash_value(StringRef S); + // StringRefs can be treated like a POD type. template struct isPodLike; template <> struct isPodLike { static const bool value = true; };