1 files changed, 53 insertions, 60 deletions

diff --git a/include/llvm/DebugInfo/DWARF/DWARFFormValue.h b/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
index d6a3b52f2fe1a..78fa6639db087 100644
--- a/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
+++ b/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
@@ -22,6 +22,35 @@ namespace llvm {
 class DWARFUnit;
 class raw_ostream;
 
+/// A helper struct for DWARFFormValue methods, providing information that
+/// allows it to know the byte size of DW_FORM values that vary in size
+/// depending on the DWARF version, address byte size, or DWARF32/DWARF64.
+struct DWARFFormParams {
+  uint16_t Version;
+  uint8_t AddrSize;
+  dwarf::DwarfFormat Format;
+
+  /// The definition of the size of form DW_FORM_ref_addr depends on the
+  /// version. In DWARF v2 it's the size of an address; after that, it's the
+  /// size of a reference.
+  uint8_t getRefAddrByteSize() const {
+    if (Version == 2)
+      return AddrSize;
+    return getDwarfOffsetByteSize();
+  }
+
+  /// The size of a reference is determined by the DWARF 32/64-bit format.
+  uint8_t getDwarfOffsetByteSize() const {
+    switch (Format) {
+    case dwarf::DwarfFormat::DWARF32:
+      return 4;
+    case dwarf::DwarfFormat::DWARF64:
+      return 8;
+    }
+    llvm_unreachable("Invalid Format value");
+  }
+};
+
 class DWARFFormValue {
 public:
   enum FormClass {
@@ -104,79 +133,43 @@ public:
 
   /// Get the fixed byte size for a given form.
   ///
-  /// If the form always has a fixed valid byte size that doesn't depend on a
-  /// DWARFUnit, then an Optional with a value will be returned. If the form
-  /// can vary in size depending on the DWARFUnit (DWARF version, address byte
-  /// size, or DWARF 32/64) and the DWARFUnit is valid, then an Optional with a
-  /// valid value is returned. If the form is always encoded using a variable
-  /// length storage format (ULEB or SLEB numbers or blocks) or the size
-  /// depends on a DWARFUnit and the DWARFUnit is NULL, then None will be
-  /// returned.
-  /// \param Form The DWARF form to get the fixed byte size for
-  /// \param U The DWARFUnit that can be used to help determine the byte size.
-  ///
-  /// \returns Optional<uint8_t> value with the fixed byte size or None if
-  /// \p Form doesn't have a fixed byte size or a DWARFUnit wasn't supplied
-  /// and was needed to calculate the byte size.
-  static Optional<uint8_t> getFixedByteSize(dwarf::Form Form,
-                                            const DWARFUnit *U = nullptr);
-
-  /// Get the fixed byte size for a given form.
-  ///
-  /// If the form has a fixed byte size given a valid DWARF version and address
-  /// byte size, then an Optional with a valid value is returned. If the form
-  /// is always encoded using a variable length storage format (ULEB or SLEB
-  /// numbers or blocks) then None will be returned.
+  /// If the form has a fixed byte size, then an Optional with a value will be
+  /// returned. If the form is always encoded using a variable length storage
+  /// format (ULEB or SLEB numbers or blocks) then None will be returned.
   ///
-  /// \param Form DWARF form to get the fixed byte size for
-  /// \param Version DWARF version number.
-  /// \param AddrSize size of an address in bytes.
-  /// \param Format enum value from llvm::dwarf::DwarfFormat.
+  /// \param Form DWARF form to get the fixed byte size for.
+  /// \param FormParams DWARF parameters to help interpret forms.
   /// \returns Optional<uint8_t> value with the fixed byte size or None if
   /// \p Form doesn't have a fixed byte size.
-  static Optional<uint8_t> getFixedByteSize(dwarf::Form Form, uint16_t Version,
-                                            uint8_t AddrSize,
-                                            llvm::dwarf::DwarfFormat Format);
+  static Optional<uint8_t> getFixedByteSize(dwarf::Form Form,
+                                            const DWARFFormParams FormParams);
 
-  /// Skip a form in \p DebugInfoData at offset specified by \p OffsetPtr.
+  /// Skip a form's value in \p DebugInfoData at the offset specified by
+  /// \p OffsetPtr.
   ///
-  /// Skips the bytes for this form in the debug info and updates the offset.
+  /// Skips the bytes for the current form and updates the offset.
   ///
-  /// \param DebugInfoData the .debug_info data to use to skip the value.
-  /// \param OffsetPtr a reference to the offset that will be updated.
-  /// \param U the DWARFUnit to use when skipping the form in case the form
-  /// size differs according to data in the DWARFUnit.
+  /// \param DebugInfoData The data where we want to skip the value.
+  /// \param OffsetPtr A reference to the offset that will be updated.
+  /// \param Params DWARF parameters to help interpret forms.
   /// \returns true on success, false if the form was not skipped.
   bool skipValue(DataExtractor DebugInfoData, uint32_t *OffsetPtr,
-                 const DWARFUnit *U) const;
-
-  /// Skip a form in \p DebugInfoData at offset specified by \p OffsetPtr.
-  ///
-  /// Skips the bytes for this form in the debug info and updates the offset.
-  ///
-  /// \param Form the DW_FORM enumeration that indicates the form to skip.
-  /// \param DebugInfoData the .debug_info data to use to skip the value.
-  /// \param OffsetPtr a reference to the offset that will be updated.
-  /// \param U the DWARFUnit to use when skipping the form in case the form
-  /// size differs according to data in the DWARFUnit.
-  /// \returns true on success, false if the form was not skipped.
-  static bool skipValue(dwarf::Form Form, DataExtractor DebugInfoData,
-                        uint32_t *OffsetPtr, const DWARFUnit *U);
+                 const DWARFFormParams Params) const {
+    return DWARFFormValue::skipValue(Form, DebugInfoData, OffsetPtr, Params);
+  }
 
-  /// Skip a form in \p DebugInfoData at offset specified by \p OffsetPtr.
+  /// Skip a form's value in \p DebugInfoData at the offset specified by
+  /// \p OffsetPtr.
   ///
-  /// Skips the bytes for this form in the debug info and updates the offset.
+  /// Skips the bytes for the specified form and updates the offset.
   ///
-  /// \param Form the DW_FORM enumeration that indicates the form to skip.
-  /// \param DebugInfoData the .debug_info data to use to skip the value.
-  /// \param OffsetPtr a reference to the offset that will be updated.
-  /// \param Version DWARF version number.
-  /// \param AddrSize size of an address in bytes.
-  /// \param Format enum value from llvm::dwarf::DwarfFormat.
+  /// \param Form The DW_FORM enumeration that indicates the form to skip.
+  /// \param DebugInfoData The data where we want to skip the value.
+  /// \param OffsetPtr A reference to the offset that will be updated.
+  /// \param FormParams DWARF parameters to help interpret forms.
   /// \returns true on success, false if the form was not skipped.
   static bool skipValue(dwarf::Form Form, DataExtractor DebugInfoData,
-                        uint32_t *OffsetPtr, uint16_t Version, uint8_t AddrSize,
-                        llvm::dwarf::DwarfFormat Format);
+                        uint32_t *OffsetPtr, const DWARFFormParams FormParams);
 
 private:
   void dumpString(raw_ostream &OS) const;