[MC] Move EH DWARF encodings from MC to CodeGen, NFC

[rnk]

Summary

The TType encoding, LSDA encoding, and personality encoding are all
passed explicitly by CodeGen to the assembler through .cfi_* directives,
so only the AsmPrinter needs to know about them.

The FDE CFI encoding however, controls the encoding of the label
implicitly created by the .cfi_startproc directive. That directive seems
to be special in that it doesn't take an encoding, so the assembler just
has to know how to encode one DSO-local label reference from .eh_frame
to .text.

As a result, it looks like MC will continue to have to know when the
large code model is in use. Perhaps we could invent a '.cfi_startproc
[large]' flag so that this knowledge doesn't need to pollute the
assembler.

[rnk]

Hm, this doesn't pass tests. Let me debug them first.

[rnk]

• Fix bug

[davide]

Yeah, this is much more in line with what I had in mind than the original patch. Thanks for taking care of this!

llvm/include/llvm/MC/MCObjectFileInfo.h

protected:
   /// without an associated EH frame section.
   bool SupportsCompactUnwindWithoutEHFrame;
 
   /// OmitDwarfIfHaveCompactUnwind - True if the target object file
   /// supports having some functions with compact unwind and other with
   /// dwarf unwind.
   bool OmitDwarfIfHaveCompactUnwind;
 
-  /// PersonalityEncoding, LSDAEncoding, TTypeEncoding - Some encoding values
-  /// for EH.
-  unsigned PersonalityEncoding;
-  unsigned LSDAEncoding;
-  unsigned FDECFIEncoding;
-  unsigned TTypeEncoding;
+  /// FDE CFI encoding. Controls the encoding of the begin label in the
+  /// .eh_frame section. Unlike the LSDA encoding, personality encoding, and
+  /// type encodings, this is something that the assembler just "knows" about
+  /// its target
+  unsigned FDECFIEncoding = 0;
 
   /// Compact unwind encoding indicating that we should emit only an EH frame.
   unsigned CompactUnwindDwarfEHFrameOnly;
 
   /// Section directive for standard text.
   MCSection *TextSection;
 
   /// Section directive for standard data.
public:
   bool getOmitDwarfIfHaveCompactUnwind() const {
     return OmitDwarfIfHaveCompactUnwind;
   }
 
   bool getCommDirectiveSupportsAlignment() const {
     return CommDirectiveSupportsAlignment;
   }
 
-  unsigned getPersonalityEncoding() const { return PersonalityEncoding; }
-  unsigned getLSDAEncoding() const { return LSDAEncoding; }
   unsigned getFDEEncoding() const { return FDECFIEncoding; }
-  unsigned getTTypeEncoding() const { return TTypeEncoding; }
 
   unsigned getCompactUnwindDwarfEHFrameOnly() const {
     return CompactUnwindDwarfEHFrameOnly;
   }
 
   MCSection *getTextSection() const { return TextSection; }
   MCSection *getDataSection() const { return DataSection; }
   MCSection *getBSSSection() const { return BSSSection; }

llvm/include/llvm/Target/TargetLoweringObjectFile.h

class TargetLoweringObjectFile : public MCObjectFileInfo {
   /// Name-mangler for global names.
   Mangler *Mang = nullptr;
 
 protected:
   bool SupportIndirectSymViaGOTPCRel = false;
   bool SupportGOTPCRelWithOffset = true;
   bool SupportDebugThreadLocalLocation = true;
 
+  /// PersonalityEncoding, LSDAEncoding, TTypeEncoding - Some encoding values
+  /// for EH.
+  unsigned PersonalityEncoding = 0;
+  unsigned LSDAEncoding = 0;
+  unsigned TTypeEncoding = 0;
+
   /// This section contains the static constructor pointer list.
   MCSection *StaticCtorSection = nullptr;
 
   /// This section contains the static destructor pointer list.
   MCSection *StaticDtorSection = nullptr;
 
 public:
   TargetLoweringObjectFile() = default;
MCSymbol *getSymbolWithGlobalValueBase(const GlobalValue *GV,
                                          StringRef Suffix,
                                          const TargetMachine &TM) const;
 
   // The symbol that gets passed to .cfi_personality.
   virtual MCSymbol *getCFIPersonalitySymbol(const GlobalValue *GV,
                                             const TargetMachine &TM,
                                             MachineModuleInfo *MMI) const;
 
+  unsigned getPersonalityEncoding() const { return PersonalityEncoding; }
+  unsigned getLSDAEncoding() const { return LSDAEncoding; }
+  unsigned getTTypeEncoding() const { return TTypeEncoding; }
+
   const MCExpr *getTTypeReference(const MCSymbolRefExpr *Sym, unsigned Encoding,
                                   MCStreamer &Streamer) const;
 
   virtual MCSection *getStaticCtorSection(unsigned Priority,
                                           const MCSymbol *KeySym) const {
     return StaticCtorSection;
   }
 

llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp

 //===----------------------------------------------------------------------===//
 //                                  ELF
 //===----------------------------------------------------------------------===//
 
 void TargetLoweringObjectFileELF::Initialize(MCContext &Ctx,
                                              const TargetMachine &TgtM) {
   TargetLoweringObjectFile::Initialize(Ctx, TgtM);
   TM = &TgtM;
+
+  bool Large = TgtM.getCodeModel() == CodeModel::Large;
+
+  switch (TgtM.getTargetTriple().getArch()) {
+  case Triple::arm:
+  case Triple::armeb:
+  case Triple::thumb:
+  case Triple::thumbeb:
+    if (Ctx.getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM)
+      break;
+    // Fallthrough if not using EHABI
+    LLVM_FALLTHROUGH;
+  case Triple::ppc:
+  case Triple::x86:
+    PersonalityEncoding = isPositionIndependent()
+                              ? dwarf::DW_EH_PE_indirect |
+                                    dwarf::DW_EH_PE_pcrel |
+                                    dwarf::DW_EH_PE_sdata4
+                              : dwarf::DW_EH_PE_absptr;
+    LSDAEncoding = isPositionIndependent()
+                       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
+                       : dwarf::DW_EH_PE_absptr;
+    TTypeEncoding = isPositionIndependent()
+                        ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+                              dwarf::DW_EH_PE_sdata4
+                        : dwarf::DW_EH_PE_absptr;
+    break;
+  case Triple::x86_64:
+    if (isPositionIndependent()) {
+      PersonalityEncoding =
+          dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+          (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
+      LSDAEncoding = dwarf::DW_EH_PE_pcrel |
+                     (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
+      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+                      (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
+    } else {
+      PersonalityEncoding =
+          Large ? dwarf::DW_EH_PE_absptr : dwarf::DW_EH_PE_udata4;
+      LSDAEncoding = Large ? dwarf::DW_EH_PE_absptr : dwarf::DW_EH_PE_udata4;
+      TTypeEncoding = Large ? dwarf::DW_EH_PE_absptr : dwarf::DW_EH_PE_udata4;
+    }
+    break;
+  case Triple::hexagon:
+    PersonalityEncoding = dwarf::DW_EH_PE_absptr;
+    LSDAEncoding = dwarf::DW_EH_PE_absptr;
+    TTypeEncoding = dwarf::DW_EH_PE_absptr;
+    if (isPositionIndependent()) {
+      PersonalityEncoding |= dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel;
+      LSDAEncoding |= dwarf::DW_EH_PE_pcrel;
+      TTypeEncoding |= dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel;
+    }
+    break;
+  case Triple::aarch64:
+  case Triple::aarch64_be:
+    // The small model guarantees static code/data size < 4GB, but not where it
+    // will be in memory. Most of these could end up >2GB away so even a signed
+    // pc-relative 32-bit address is insufficient, theoretically.
+    if (isPositionIndependent()) {
+      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+        dwarf::DW_EH_PE_sdata8;
+      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8;
+      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+        dwarf::DW_EH_PE_sdata8;
+    } else {
+      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
+      LSDAEncoding = dwarf::DW_EH_PE_absptr;
+      TTypeEncoding = dwarf::DW_EH_PE_absptr;
+    }
+    break;
+  case Triple::lanai:
+    LSDAEncoding = dwarf::DW_EH_PE_absptr;
+    PersonalityEncoding = dwarf::DW_EH_PE_absptr;
+    TTypeEncoding = dwarf::DW_EH_PE_absptr;
+    break;
+  case Triple::mips:
+  case Triple::mipsel:
+  case Triple::mips64:
+  case Triple::mips64el:
+    // MIPS uses indirect pointer to refer personality functions and types, so
+    // that the eh_frame section can be read-only. DW.ref.personality will be
+    // generated for relocation.
+    PersonalityEncoding = dwarf::DW_EH_PE_indirect;
+    // FIXME: The N64 ABI probably ought to use DW_EH_PE_sdata8 but we can't
+    //        identify N64 from just a triple.
+    TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+                    dwarf::DW_EH_PE_sdata4;
+    // We don't support PC-relative LSDA references in GAS so we use the default
+    // DW_EH_PE_absptr for those.
+
+    // FreeBSD must be explicit about the data size and using pcrel since it's
+    // assembler/linker won't do the automatic conversion that the Linux tools
+    // do.
+    if (TgtM.getTargetTriple().isOSFreeBSD()) {
+      PersonalityEncoding |= dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
+      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
+    }
+    break;
+  case Triple::ppc64:
+  case Triple::ppc64le:
+    PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+      dwarf::DW_EH_PE_udata8;
+    LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
+    TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+      dwarf::DW_EH_PE_udata8;
+    break;
+  case Triple::sparcel:
+  case Triple::sparc:
+    if (isPositionIndependent()) {
+      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
+      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+        dwarf::DW_EH_PE_sdata4;
+      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+        dwarf::DW_EH_PE_sdata4;
+    } else {
+      LSDAEncoding = dwarf::DW_EH_PE_absptr;
+      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
+      TTypeEncoding = dwarf::DW_EH_PE_absptr;
+    }
+    break;
+  case Triple::sparcv9:
+    LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
+    if (isPositionIndependent()) {
+      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+        dwarf::DW_EH_PE_sdata4;
+      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+        dwarf::DW_EH_PE_sdata4;
+    } else {
+      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
+      TTypeEncoding = dwarf::DW_EH_PE_absptr;
+    }
+    break;
+  case Triple::systemz:
+    // All currently-defined code models guarantee that 4-byte PC-relative
+    // values will be in range.
+    if (isPositionIndependent()) {
+      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+        dwarf::DW_EH_PE_sdata4;
+      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
+      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+        dwarf::DW_EH_PE_sdata4;
+    } else {
+      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
+      LSDAEncoding = dwarf::DW_EH_PE_absptr;
+      TTypeEncoding = dwarf::DW_EH_PE_absptr;
+    }
+    break;
+  default:
+    break;
+  }
 }
 
 void TargetLoweringObjectFileELF::emitModuleMetadata(MCStreamer &Streamer,
                                                      Module &M) const {
   auto &C = getContext();
 
   if (NamedMDNode *LinkerOptions = M.getNamedMetadata("llvm.linker.options")) {
     auto *S = C.getELFSection(".linker-options", ELF::SHT_LLVM_LINKER_OPTIONS,
void TargetLoweringObjectFileMachO::Initialize(MCContext &Ctx,
   } else {
     StaticCtorSection = Ctx.getMachOSection("__DATA", "__mod_init_func",
                                             MachO::S_MOD_INIT_FUNC_POINTERS,
                                             SectionKind::getData());
     StaticDtorSection = Ctx.getMachOSection("__DATA", "__mod_term_func",
                                             MachO::S_MOD_TERM_FUNC_POINTERS,
                                             SectionKind::getData());
   }
+
+  PersonalityEncoding =
+      dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
+  LSDAEncoding = dwarf::DW_EH_PE_pcrel;
+  TTypeEncoding =
+      dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
 }
 
 void TargetLoweringObjectFileMachO::emitModuleMetadata(MCStreamer &Streamer,
                                                        Module &M) const {
   // Emit the linker options if present.
   if (auto *LinkerOptions = M.getNamedMetadata("llvm.linker.options")) {
     for (const auto &Option : LinkerOptions->operands()) {
       SmallVector<std::string, 4> StrOptions;

llvm/lib/MC/MCObjectFileInfo.cpp

EHFrameSection = Ctx->getMachOSection(
       SectionKind::getReadOnly());
 
   if (T.isOSDarwin() && T.getArch() == Triple::aarch64)
     SupportsCompactUnwindWithoutEHFrame = true;
 
   if (T.isWatchABI())
     OmitDwarfIfHaveCompactUnwind = true;
 
-  PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel
-    | dwarf::DW_EH_PE_sdata4;
-  LSDAEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel;
-  TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-    dwarf::DW_EH_PE_sdata4;
+  FDECFIEncoding = dwarf::DW_EH_PE_pcrel;
 
   // .comm doesn't support alignment before Leopard.
   if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5))
     CommDirectiveSupportsAlignment = false;
 
   TextSection // .text
     = Ctx->getMachOSection("__TEXT", "__text",
                            MachO::S_ATTR_PURE_INSTRUCTIONS,
void MCObjectFileInfo::initELFMCObjectFileInfo(const Triple &T, bool Large) {
   case Triple::x86_64:
     FDECFIEncoding = dwarf::DW_EH_PE_pcrel |
                      (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
     break;
   case Triple::bpfel:
   case Triple::bpfeb:
     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
     break;
-  default:
-    FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
-    break;
-  }
-
-  switch (T.getArch()) {
-  case Triple::arm:
-  case Triple::armeb:
-  case Triple::thumb:
-  case Triple::thumbeb:
-    if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM)
-      break;
-    // Fallthrough if not using EHABI
-    LLVM_FALLTHROUGH;
-  case Triple::ppc:
-  case Triple::x86:
-    PersonalityEncoding = PositionIndependent
-                              ? dwarf::DW_EH_PE_indirect |
-                                    dwarf::DW_EH_PE_pcrel |
-                                    dwarf::DW_EH_PE_sdata4
-                              : dwarf::DW_EH_PE_absptr;
-    LSDAEncoding = PositionIndependent
-                       ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
-                       : dwarf::DW_EH_PE_absptr;
-    TTypeEncoding = PositionIndependent
-                        ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-                              dwarf::DW_EH_PE_sdata4
-                        : dwarf::DW_EH_PE_absptr;
-    break;
-  case Triple::x86_64:
-    if (PositionIndependent) {
-      PersonalityEncoding =
-          dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-          (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
-      LSDAEncoding = dwarf::DW_EH_PE_pcrel |
-                     (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
-      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-                      (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
-    } else {
-      PersonalityEncoding =
-          Large ? dwarf::DW_EH_PE_absptr : dwarf::DW_EH_PE_udata4;
-      LSDAEncoding = Large ? dwarf::DW_EH_PE_absptr : dwarf::DW_EH_PE_udata4;
-      TTypeEncoding = Large ? dwarf::DW_EH_PE_absptr : dwarf::DW_EH_PE_udata4;
-    }
-    break;
   case Triple::hexagon:
-    PersonalityEncoding = dwarf::DW_EH_PE_absptr;
-    LSDAEncoding = dwarf::DW_EH_PE_absptr;
-    FDECFIEncoding = dwarf::DW_EH_PE_absptr;
-    TTypeEncoding = dwarf::DW_EH_PE_absptr;
-    if (PositionIndependent) {
-      PersonalityEncoding |= dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel;
-      LSDAEncoding |= dwarf::DW_EH_PE_pcrel;
-      FDECFIEncoding |= dwarf::DW_EH_PE_pcrel;
-      TTypeEncoding |= dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel;
-    }
-    break;
-  case Triple::aarch64:
-  case Triple::aarch64_be:
-    // The small model guarantees static code/data size < 4GB, but not where it
-    // will be in memory. Most of these could end up >2GB away so even a signed
-    // pc-relative 32-bit address is insufficient, theoretically.
-    if (PositionIndependent) {
-      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        dwarf::DW_EH_PE_sdata8;
-      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8;
-      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        dwarf::DW_EH_PE_sdata8;
-    } else {
-      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
-      LSDAEncoding = dwarf::DW_EH_PE_absptr;
-      TTypeEncoding = dwarf::DW_EH_PE_absptr;
-    }
-    break;
-  case Triple::lanai:
-    LSDAEncoding = dwarf::DW_EH_PE_absptr;
-    PersonalityEncoding = dwarf::DW_EH_PE_absptr;
-    TTypeEncoding = dwarf::DW_EH_PE_absptr;
-    break;
-  case Triple::mips:
-  case Triple::mipsel:
-  case Triple::mips64:
-  case Triple::mips64el:
-    // MIPS uses indirect pointer to refer personality functions and types, so
-    // that the eh_frame section can be read-only. DW.ref.personality will be
-    // generated for relocation.
-    PersonalityEncoding = dwarf::DW_EH_PE_indirect;
-    // FIXME: The N64 ABI probably ought to use DW_EH_PE_sdata8 but we can't
-    //        identify N64 from just a triple.
-    TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-                    dwarf::DW_EH_PE_sdata4;
-    // We don't support PC-relative LSDA references in GAS so we use the default
-    // DW_EH_PE_absptr for those.
-
-    // FreeBSD must be explicit about the data size and using pcrel since it's
-    // assembler/linker won't do the automatic conversion that the Linux tools
-    // do.
-    if (T.isOSFreeBSD()) {
-      PersonalityEncoding |= dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
-      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
-    }
-    break;
-  case Triple::ppc64:
-  case Triple::ppc64le:
-    PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-      dwarf::DW_EH_PE_udata8;
-    LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
-    TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-      dwarf::DW_EH_PE_udata8;
-    break;
-  case Triple::sparcel:
-  case Triple::sparc:
-    if (PositionIndependent) {
-      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
-      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        dwarf::DW_EH_PE_sdata4;
-      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        dwarf::DW_EH_PE_sdata4;
-    } else {
-      LSDAEncoding = dwarf::DW_EH_PE_absptr;
-      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
-      TTypeEncoding = dwarf::DW_EH_PE_absptr;
-    }
-    break;
-  case Triple::sparcv9:
-    LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
-    if (PositionIndependent) {
-      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        dwarf::DW_EH_PE_sdata4;
-      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        dwarf::DW_EH_PE_sdata4;
-    } else {
-      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
-      TTypeEncoding = dwarf::DW_EH_PE_absptr;
-    }
-    break;
-  case Triple::systemz:
-    // All currently-defined code models guarantee that 4-byte PC-relative
-    // values will be in range.
-    if (PositionIndependent) {
-      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        dwarf::DW_EH_PE_sdata4;
-      LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
-      TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        dwarf::DW_EH_PE_sdata4;
-    } else {
-      PersonalityEncoding = dwarf::DW_EH_PE_absptr;
-      LSDAEncoding = dwarf::DW_EH_PE_absptr;
-      TTypeEncoding = dwarf::DW_EH_PE_absptr;
-    }
-    break;
+    FDECFIEncoding =
+        PositionIndependent ? dwarf::DW_EH_PE_pcrel : dwarf::DW_EH_PE_absptr;
   default:
+    FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
     break;
   }
 
   unsigned EHSectionType = T.getArch() == Triple::x86_64
                                ? ELF::SHT_X86_64_UNWIND
                                : ELF::SHT_PROGBITS;
 
   // Solaris requires different flags for .eh_frame to seemingly every other
void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple, bool PIC,
   Ctx = &ctx;
 
   // Common.
   CommDirectiveSupportsAlignment = true;
   SupportsWeakOmittedEHFrame = true;
   SupportsCompactUnwindWithoutEHFrame = false;
   OmitDwarfIfHaveCompactUnwind = false;
 
-  PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding =
-      dwarf::DW_EH_PE_absptr;
+  FDECFIEncoding = dwarf::DW_EH_PE_absptr;
 
   CompactUnwindDwarfEHFrameOnly = 0;
 
   EHFrameSection = nullptr;             // Created on demand.
   CompactUnwindSection = nullptr;       // Used only by selected targets.
   DwarfAccelNamesSection = nullptr;     // Used only by selected targets.
   DwarfAccelObjCSection = nullptr;      // Used only by selected targets.
   DwarfAccelNamespaceSection = nullptr; // Used only by selected targets.

llvm/lib/Target/TargetLoweringObjectFile.cpp

 void TargetLoweringObjectFile::Initialize(MCContext &ctx,
                                           const TargetMachine &TM) {
   Ctx = &ctx;
   // `Initialize` can be called more than once.
   delete Mang;
   Mang = new Mangler();
   InitMCObjectFileInfo(TM.getTargetTriple(), TM.isPositionIndependent(), *Ctx,
                        TM.getCodeModel() == CodeModel::Large);
+
+  // Reset various EH DWARF encodings.
+  PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding =
+      dwarf::DW_EH_PE_absptr;
 }
 
 TargetLoweringObjectFile::~TargetLoweringObjectFile() {
   delete Mang;
 }
 
 static bool isNullOrUndef(const Constant *C) {
   // Check that the constant isn't all zeros or undefs.