include/llvm/Option/Arg.h

   1 //===- Arg.h - Parsed Argument Classes --------------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 ///
   9 /// \file
  10 /// Defines the llvm::Arg class for parsed arguments.
  11 ///
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_OPTION_ARG_H
  15 #define LLVM_OPTION_ARG_H
  16
  17 #include "llvm/ADT/SmallVector.h"
  18 #include "llvm/ADT/StringRef.h"
  19 #include "llvm/Option/Option.h"
  20 #include <string>
  21
  22 namespace llvm {
  23
  24 class raw_ostream;
  25
  26 namespace opt {
  27
  28 class ArgList;
  29
  30 /// A concrete instance of a particular driver option.
  31 ///
  32 /// The Arg class encodes just enough information to be able to
  33 /// derive the argument values efficiently.
  34 class Arg {
  35 private:
  36   /// The option this argument is an instance of.
  37   const Option Opt;
  38
  39   /// The argument this argument was derived from (during tool chain
  40   /// argument translation), if any.
  41   const Arg *BaseArg;
  42
  43   /// How this instance of the option was spelled.
  44   StringRef Spelling;
  45
  46   /// The index at which this argument appears in the containing
  47   /// ArgList.
  48   unsigned Index;
  49
  50   /// Was this argument used to effect compilation?
  51   ///
  52   /// This is used for generating "argument unused" diagnostics.
  53   mutable unsigned Claimed : 1;
  54
  55   /// Does this argument own its values?
  56   mutable unsigned OwnsValues : 1;
  57
  58   /// The argument values, as C strings.
  59   SmallVector<const char *, 2> Values;
  60
  61   /// If this arg was created through an alias, this is the original alias arg.
  62   /// For example, *this might be "-finput-charset=utf-8" and Alias might
  63   /// point to an arg representing "/source-charset:utf-8".
  64   std::unique_ptr<Arg> Alias;
  65
  66 public:
  67   Arg(const Option Opt, StringRef Spelling, unsigned Index,
  68       const Arg *BaseArg = nullptr);
  69   Arg(const Option Opt, StringRef Spelling, unsigned Index,
  70       const char *Value0, const Arg *BaseArg = nullptr);
  71   Arg(const Option Opt, StringRef Spelling, unsigned Index,
  72       const char *Value0, const char *Value1, const Arg *BaseArg = nullptr);
  73   Arg(const Arg &) = delete;
  74   Arg &operator=(const Arg &) = delete;
  75   ~Arg();
  76
  77   const Option &getOption() const { return Opt; }
  78
  79   /// Returns the used prefix and name of the option:
  80   /// For `--foo=bar`, returns `--foo=`.
  81   /// This is often the wrong function to call:
  82   /// * Use `getValue()` to get `bar`.
  83   /// * Use `getAsString()` to get a string suitable for printing an Arg in
  84   ///   a diagnostic.
  85   StringRef getSpelling() const { return Spelling; }
  86
  87   unsigned getIndex() const { return Index; }
  88
  89   /// Return the base argument which generated this arg.
  90   ///
  91   /// This is either the argument itself or the argument it was
  92   /// derived from during tool chain specific argument translation.
  93   const Arg &getBaseArg() const {
  94     return BaseArg ? *BaseArg : *this;
  95   }
  96   void setBaseArg(const Arg *BaseArg) { this->BaseArg = BaseArg; }
  97
  98   /// Args are converted to their unaliased form.  For args that originally
  99   /// came from an alias, this returns the alias the arg was produced from.
 100   const Arg* getAlias() const { return Alias.get(); }
 101   void setAlias(std::unique_ptr<Arg> Alias) { this->Alias = std::move(Alias); }
 102
 103   bool getOwnsValues() const { return OwnsValues; }
 104   void setOwnsValues(bool Value) const { OwnsValues = Value; }
 105
 106   bool isClaimed() const { return getBaseArg().Claimed; }
 107
 108   /// Set the Arg claimed bit.
 109   void claim() const { getBaseArg().Claimed = true; }
 110
 111   unsigned getNumValues() const { return Values.size(); }
 112
 113   const char *getValue(unsigned N = 0) const {
 114     return Values[N];
 115   }
 116
 117   SmallVectorImpl<const char *> &getValues() { return Values; }
 118   const SmallVectorImpl<const char *> &getValues() const { return Values; }
 119
 120   bool containsValue(StringRef Value) const {
 121     for (unsigned i = 0, e = getNumValues(); i != e; ++i)
 122       if (Values[i] == Value)
 123         return true;
 124     return false;
 125   }
 126
 127   /// Append the argument onto the given array as strings.
 128   void render(const ArgList &Args, ArgStringList &Output) const;
 129
 130   /// Append the argument, render as an input, onto the given
 131   /// array as strings.
 132   ///
 133   /// The distinction is that some options only render their values
 134   /// when rendered as a input (e.g., Xlinker).
 135   void renderAsInput(const ArgList &Args, ArgStringList &Output) const;
 136
 137   void print(raw_ostream &O) const;
 138   void dump() const;
 139
 140   /// Return a formatted version of the argument and its values, for
 141   /// diagnostics. Since this is for diagnostics, if this Arg was produced
 142   /// through an alias, this returns the string representation of the alias
 143   /// that the user wrote.
 144   std::string getAsString(const ArgList &Args) const;
 145 };
 146
 147 } // end namespace opt
 148
 149 } // end namespace llvm
 150
 151 #endif // LLVM_OPTION_ARG_H