[DWARF] NFC: Collect info used by DWARFFormValue into a helper.

Some forms have sizes that depend on the DWARF version, DWARF format
(32/64-bit), or the size of an address.  Collect these into a struct
to simplify passing them around.  Require callers to provide one when
they query a form's size.

Differential Revision: http://reviews.llvm.org/D34570

llvm-svn: 306315

1 files changed, 14 insertions, 81 deletions

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFFormValue.cpp b/llvm/lib/DebugInfo/DWARF/DWARFFormValue.cpp
index 39c1f5fd5c5..dda4a0cdb31 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFFormValue.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFFormValue.cpp
@@ -59,48 +59,13 @@ static const DWARFFormValue::FormClass DWARF4FormClasses[] = {
     DWARFFormValue::FC_Flag,          // 0x19 DW_FORM_flag_present
 };
 
-namespace {
-
-/// A helper class that can be used in DWARFFormValue.cpp functions that need
-/// to know the byte size of DW_FORM values that vary in size depending on the
-/// DWARF version, address byte size, or DWARF32 or DWARF64.
-class FormSizeHelper {
-  uint16_t Version;
-  uint8_t AddrSize;
-  llvm::dwarf::DwarfFormat Format;
-
-public:
-  FormSizeHelper(uint16_t V, uint8_t A, llvm::dwarf::DwarfFormat F)
-      : Version(V), AddrSize(A), Format(F) {}
-
-  uint8_t getAddressByteSize() const { return AddrSize; }
-
-  uint8_t getRefAddrByteSize() const {
-    if (Version == 2)
-      return AddrSize;
-    return getDwarfOffsetByteSize();
-  }
-
-  uint8_t getDwarfOffsetByteSize() const {
-    switch (Format) {
-    case dwarf::DwarfFormat::DWARF32:
-      return 4;
-    case dwarf::DwarfFormat::DWARF64:
-      return 8;
-    }
-    llvm_unreachable("Invalid Format value");
-  }
-};
-
-} // end anonymous namespace
-
-template <class T>
-static Optional<uint8_t> getFixedByteSize(dwarf::Form Form, const T *U) {
+Optional<uint8_t>
+DWARFFormValue::getFixedByteSize(dwarf::Form Form,
+                                 const DWARFFormParams &Params) {
   switch (Form) {
   case DW_FORM_addr:
-    if (U)
-      return U->getAddressByteSize();
-    return None;
+    assert(Params.Version && Params.AddrSize && "Invalid Params for form");
+    return Params.AddrSize;
 
   case DW_FORM_block:          // ULEB128 length L followed by L bytes.
   case DW_FORM_block1:         // 1 byte length L followed by L bytes.
@@ -121,9 +86,8 @@ static Optional<uint8_t> getFixedByteSize(dwarf::Form Form, const T *U) {
     return None;
 
   case DW_FORM_ref_addr:
-    if (U)
-      return U->getRefAddrByteSize();
-    return None;
+    assert(Params.Version && Params.AddrSize && "Invalid Params for form");
+    return Params.getRefAddrByteSize();
 
   case DW_FORM_flag:
   case DW_FORM_data1:
@@ -154,9 +118,8 @@ static Optional<uint8_t> getFixedByteSize(dwarf::Form Form, const T *U) {
   case DW_FORM_line_strp:
   case DW_FORM_sec_offset:
   case DW_FORM_strp_sup:
-    if (U)
-      return U->getDwarfOffsetByteSize();
-    return None;
+    assert(Params.Version && Params.AddrSize && "Invalid Params for form");
+    return Params.getDwarfOffsetByteSize();
 
   case DW_FORM_data8:
   case DW_FORM_ref8:
@@ -181,9 +144,9 @@ static Optional<uint8_t> getFixedByteSize(dwarf::Form Form, const T *U) {
   return None;
 }
 
-template <class T>
-static bool skipFormValue(dwarf::Form Form, const DataExtractor &DebugInfoData,
-                          uint32_t *OffsetPtr, const T *U) {
+bool DWARFFormValue::skipValue(dwarf::Form Form, DataExtractor DebugInfoData,
+                               uint32_t *OffsetPtr,
+                               const DWARFFormParams &Params) {
   bool Indirect = false;
   do {
     switch (Form) {
@@ -243,7 +206,8 @@ static bool skipFormValue(dwarf::Form Form, const DataExtractor &DebugInfoData,
     case DW_FORM_line_strp:
     case DW_FORM_GNU_ref_alt:
     case DW_FORM_GNU_strp_alt:
-      if (Optional<uint8_t> FixedSize = ::getFixedByteSize(Form, U)) {
+      if (Optional<uint8_t> FixedSize =
+              DWARFFormValue::getFixedByteSize(Form, Params)) {
         *OffsetPtr += *FixedSize;
         return true;
       }
@@ -277,19 +241,6 @@ static bool skipFormValue(dwarf::Form Form, const DataExtractor &DebugInfoData,
   return true;
 }
 
-Optional<uint8_t> DWARFFormValue::getFixedByteSize(dwarf::Form Form,
-                                                   const DWARFUnit *U) {
-  return ::getFixedByteSize(Form, U);
-}
-
-Optional<uint8_t>
-DWARFFormValue::getFixedByteSize(dwarf::Form Form, uint16_t Version,
-                                 uint8_t AddrSize,
-                                 llvm::dwarf::DwarfFormat Format) {
-  FormSizeHelper FSH(Version, AddrSize, Format);
-  return ::getFixedByteSize(Form, &FSH);
-}
-
 bool DWARFFormValue::isFormClass(DWARFFormValue::FormClass FC) const {
   // First, check DWARF4 form classes.
   if (Form < makeArrayRef(DWARF4FormClasses).size() &&
@@ -448,24 +399,6 @@ bool DWARFFormValue::extractValue(const DataExtractor &Data,
   return true;
 }
 
-bool DWARFFormValue::skipValue(DataExtractor DebugInfoData, uint32_t *OffsetPtr,
-                               const DWARFUnit *U) const {
-  return DWARFFormValue::skipValue(Form, DebugInfoData, OffsetPtr, U);
-}
-
-bool DWARFFormValue::skipValue(dwarf::Form Form, DataExtractor DebugInfoData,
-                               uint32_t *OffsetPtr, const DWARFUnit *U) {
-  return skipFormValue(Form, DebugInfoData, OffsetPtr, U);
-}
-
-bool DWARFFormValue::skipValue(dwarf::Form Form, DataExtractor DebugInfoData,
-                               uint32_t *OffsetPtr, uint16_t Version,
-                               uint8_t AddrSize,
-                               llvm::dwarf::DwarfFormat Format) {
-  FormSizeHelper FSH(Version, AddrSize, Format);
-  return skipFormValue(Form, DebugInfoData, OffsetPtr, &FSH);
-}
-
 void DWARFFormValue::dump(raw_ostream &OS) const {
   uint64_t UValue = Value.uval;
   bool CURelativeOffset = false;