Record debug information about a field in a struct type.

Record debug information about a field within a bitfield. For example, the following C struct:

struct s {
  int32_t w;
  uint8_t x1:1;
  uint8_t x2:2;
  uint8_t y:1;
  int32_t z;
};

Corresponds to the following Info:

Structure
  [ StructFieldInfo { sfiName = "w"
                      , sfiOffset = 0
                      , sfiBitfield = Nothing
                      , sfiInfo = BaseType "int32_t"
                      }
  , StructFieldInfo { sfiName = "x1"
                      , sfiOffset = 32
                      , sfiBitfield = Just (BitfieldInfo { biFieldSize = 1
                                                             , biBitfieldOffset = 32
                                                             })
                      , sfiInfo = BaseType "uint8_t"
                      }
  , StructFieldInfo { sfiName = "x2"
                      , sfiOffset = 33
                      , sfiBitfield = Just (BitfieldInfo { biFieldSize = 2
                                                             , biBitfieldOffset = 32
                                                             })
                      , sfiInfo = BaseType "uint8_t"
                      }
  , StructFieldInfo { sfiName = "y"
                      , sfiOffset = 35
                      , sfiBitfield = Just (BitfieldInfo { biFieldSize = 1
                                                             , biBitfieldOffset = 32
                                                             })
                      , sfiInfo = BaseType "uint8_t"
                      }
  , StructFieldInfo { sfiName = "z"
                      , sfiOffset = 64
                      , sfiBitfield = Nothing
                      , sfiInfo = BaseType "int32_t"
                      }
  ]

Notice that only x1, x2, and y have BitfieldInfos, as they are the only fields that were declared with bitfield syntax.

Record debug information about a field in a union type.

Compute the structures of a function's return and argument types using DWARF information metadata of the LLVM module. Different versions of LLVM make this information available via different paths. This function attempts to support the variations.

Compute an IntMap of the unnamed metadata in a module

If the argument describes a pointer, return the information for the type that it points do. If the argument describes an array, return information about the element type.

If the argument describes a composite type, returns the type of the field by zero-based index into the list of fields.

If the argument describes a composite type, return the first, zero-based index of the field in that type that matches the given name.

Search the metadata for debug info corresponding to a given type alias. This is considered a heuristic because there's no direct mapping between type aliases and debug info. The debug information must be search for a textual match.

Compared to guessTypeInfo, this function first tries to strip the "struct." and "union." prefixes that are commonly added by clang before searching for the type information.

Search the metadata for debug info corresponding to a given type alias. This is considered a heuristic because there's no direct mapping between type aliases and debug info. The debug information must be search for a textual match.

Find source-level names of function arguments

Map global variable names to the line on which the global is defined

Map function names to the line on which the function is defined