Move function info word into its own data structure (#153627)

The sframe generator needs to construct this word separately from FDEs
themselves, so split them into a separate data structure.

Author: Sterling-Augustine

llvm/include/llvm/BinaryFormat/SFrame.h

@@ -104,14 +104,8 @@ template <endianness E> struct Header {
   detail::packed<uint32_t, E> FREOff;
 };
 
-template <endianness E> struct FuncDescEntry {
-  detail::packed<int32_t, E> StartAddress;
-  detail::packed<uint32_t, E> Size;
-  detail::packed<uint32_t, E> StartFREOff;
-  detail::packed<uint32_t, E> NumFREs;
+template <endianness E> struct FDEInfo {
   detail::packed<uint8_t, E> Info;
-  detail::packed<uint8_t, E> RepSize;
-  detail::packed<uint16_t, E> Padding2;
 
   uint8_t getPAuthKey() const { return (Info >> 5) & 1; }
   FDEType getFDEType() const { return static_cast<FDEType>((Info >> 4) & 1); }
@@ -125,6 +119,16 @@ template <endianness E> struct FuncDescEntry {
   }
 };
 
+template <endianness E> struct FuncDescEntry {
+  detail::packed<int32_t, E> StartAddress;
+  detail::packed<uint32_t, E> Size;
+  detail::packed<uint32_t, E> StartFREOff;
+  detail::packed<uint32_t, E> NumFREs;
+  FDEInfo<E> Info;
+  detail::packed<uint8_t, E> RepSize;
+  detail::packed<uint16_t, E> Padding2;
+};
+
 template <endianness E> struct FREInfo {
   detail::packed<uint8_t, E> Info;
 

llvm/lib/Object/SFrameParser.cpp

@@ -176,10 +176,10 @@ iterator_range<typename SFrameParser<E>::fre_iterator>
 SFrameParser<E>::fres(const sframe::FuncDescEntry<E> &FDE, Error &Err) const {
   uint64_t Offset = getFREBase() + FDE.StartFREOff;
   fre_iterator BeforeBegin = make_fallible_itr(
-      FallibleFREIterator(Data, FDE.getFREType(), -1, FDE.NumFREs, Offset),
+      FallibleFREIterator(Data, FDE.Info.getFREType(), -1, FDE.NumFREs, Offset),
       Err);
   fre_iterator End = make_fallible_end(
-      FallibleFREIterator(Data, FDE.getFREType(), FDE.NumFREs, FDE.NumFREs,
+      FallibleFREIterator(Data, FDE.Info.getFREType(), FDE.NumFREs, FDE.NumFREs,
                           /*Offset=*/0));
   return {++BeforeBegin, End};
 }

llvm/tools/llvm-readobj/ELFDumper.cpp

@@ -6512,25 +6512,27 @@ void ELFDumper<ELFT>::printSFrameFDEs(
 
     {
       DictScope InfoScope(W, "Info");
-      W.printEnum("FRE Type", It->getFREType(), sframe::getFRETypes());
-      W.printEnum("FDE Type", It->getFDEType(), sframe::getFDETypes());
+      W.printEnum("FRE Type", It->Info.getFREType(), sframe::getFRETypes());
+      W.printEnum("FDE Type", It->Info.getFDEType(), sframe::getFDETypes());
       switch (Parser.getHeader().ABIArch) {
       case sframe::ABI::AArch64EndianBig:
       case sframe::ABI::AArch64EndianLittle:
-        W.printEnum("PAuth Key", sframe::AArch64PAuthKey(It->getPAuthKey()),
+        W.printEnum("PAuth Key",
+                    sframe::AArch64PAuthKey(It->Info.getPAuthKey()),
                     sframe::getAArch64PAuthKeys());
         break;
       case sframe::ABI::AMD64EndianLittle:
         // unused
         break;
       }
 
-      W.printHex("Raw", It->Info);
+      W.printHex("Raw", It->Info.Info);
     }
 
     W.printHex(
         ("Repetitive block size" +
-         Twine(It->getFDEType() == sframe::FDEType::PCMask ? "" : " (unused)"))
+         Twine(It->Info.getFDEType() == sframe::FDEType::PCMask ? ""
+                                                                : " (unused)"))
             .str(),
         It->RepSize);
 
@@ -6541,10 +6543,11 @@ void ELFDumper<ELFT>::printSFrameFDEs(
     for (const typename SFrameParser<ELFT::Endianness>::FrameRowEntry &FRE :
          Parser.fres(*It, Err)) {
       DictScope FREScope(W, "Frame Row Entry");
-      W.printHex(
-          "Start Address",
-          (It->getFDEType() == sframe::FDEType::PCInc ? FDEStartAddress : 0) +
-              FRE.StartAddress);
+      W.printHex("Start Address",
+                 (It->Info.getFDEType() == sframe::FDEType::PCInc
+                      ? FDEStartAddress
+                      : 0) +
+                     FRE.StartAddress);
       W.printBoolean("Return Address Signed", FRE.Info.isReturnAddressSigned());
       W.printEnum("Offset Size", FRE.Info.getOffsetSize(),
                   sframe::getFREOffsets());

llvm/unittests/BinaryFormat/SFrameTest.cpp

@@ -54,28 +54,28 @@ TYPED_TEST_SUITE(SFrameTest, Types, NameGenerator);
 
 TYPED_TEST(SFrameTest, FDEFlags) {
   FuncDescEntry<TestFixture::Endian> FDE = {};
-  EXPECT_EQ(FDE.Info, 0u);
-  EXPECT_EQ(FDE.getPAuthKey(), 0);
-  EXPECT_EQ(FDE.getFDEType(), FDEType::PCInc);
-  EXPECT_EQ(FDE.getFREType(), FREType::Addr1);
-
-  FDE.setPAuthKey(1);
-  EXPECT_EQ(FDE.Info, 0x20u);
-  EXPECT_EQ(FDE.getPAuthKey(), 1);
-  EXPECT_EQ(FDE.getFDEType(), FDEType::PCInc);
-  EXPECT_EQ(FDE.getFREType(), FREType::Addr1);
-
-  FDE.setFDEType(FDEType::PCMask);
-  EXPECT_EQ(FDE.Info, 0x30u);
-  EXPECT_EQ(FDE.getPAuthKey(), 1);
-  EXPECT_EQ(FDE.getFDEType(), FDEType::PCMask);
-  EXPECT_EQ(FDE.getFREType(), FREType::Addr1);
-
-  FDE.setFREType(FREType::Addr4);
-  EXPECT_EQ(FDE.Info, 0x32u);
-  EXPECT_EQ(FDE.getPAuthKey(), 1);
-  EXPECT_EQ(FDE.getFDEType(), FDEType::PCMask);
-  EXPECT_EQ(FDE.getFREType(), FREType::Addr4);
+  EXPECT_EQ(FDE.Info.Info, 0u);
+  EXPECT_EQ(FDE.Info.getPAuthKey(), 0);
+  EXPECT_EQ(FDE.Info.getFDEType(), FDEType::PCInc);
+  EXPECT_EQ(FDE.Info.getFREType(), FREType::Addr1);
+
+  FDE.Info.setPAuthKey(1);
+  EXPECT_EQ(FDE.Info.Info, 0x20u);
+  EXPECT_EQ(FDE.Info.getPAuthKey(), 1);
+  EXPECT_EQ(FDE.Info.getFDEType(), FDEType::PCInc);
+  EXPECT_EQ(FDE.Info.getFREType(), FREType::Addr1);
+
+  FDE.Info.setFDEType(FDEType::PCMask);
+  EXPECT_EQ(FDE.Info.Info, 0x30u);
+  EXPECT_EQ(FDE.Info.getPAuthKey(), 1);
+  EXPECT_EQ(FDE.Info.getFDEType(), FDEType::PCMask);
+  EXPECT_EQ(FDE.Info.getFREType(), FREType::Addr1);
+
+  FDE.Info.setFREType(FREType::Addr4);
+  EXPECT_EQ(FDE.Info.Info, 0x32u);
+  EXPECT_EQ(FDE.Info.getPAuthKey(), 1);
+  EXPECT_EQ(FDE.Info.getFDEType(), FDEType::PCMask);
+  EXPECT_EQ(FDE.Info.getFREType(), FREType::Addr4);
 }
 
 TYPED_TEST(SFrameTest, FREFlags) {