Revert changes made in rdar://133264719 and rdar://133001453

A significant amount of changes were made upstream to MCAssembler and
MachObjectWriter that broke MCCAS. To fix them, we moved a bunch of code
from MachObjectWriter to MCObjectWriter as a band-aid fix, but those are
full of layering violations, this patch reverts those changes in favor
of a correct fix in the next commit which involves rewriting
MachOCASWriter to be a derived class if MachObjectWriter.

(cherry picked from commit 91e9561)

Author: rastogishubham

clang/test/CAS/path-independent-cas-outputs.c

@@ -44,9 +44,9 @@
 
 // Baseline to check we got expected outputs.
 // RUN: %clang -target x86_64-apple-macos11 -c %s -o %t/t.o -MMD -MT dependencies -MF %t/t.d --serialize-diagnostics %t/t.dia
-// RUN: env LLVM_CACHE_CAS_PATH=%t/a/cas %clang-cache \
+// RUN: env LLVM_CACHE_CAS_PATH=%t/a/cas CLANG_CACHE_DISABLE_MCCAS=1 %clang-cache \
 // RUN:   %clang -target x86_64-apple-macos11 -c %s -o %t/a/t1.o -MMD -MT dependencies -MF %t/a/t1.d --serialize-diagnostics %t/a/t1.dia
-// RUN: env LLVM_CACHE_CAS_PATH=%t/b/cas %clang-cache \
+// RUN: env LLVM_CACHE_CAS_PATH=%t/b/cas CLANG_CACHE_DISABLE_MCCAS=1 %clang-cache \
 // RUN:   %clang -target x86_64-apple-macos11 -c %s -o %t/b/t2.o -MMD -MT dependencies -MF %t/b/t2.d --serialize-diagnostics %t/b/t2.dia
 
 // RUN: diff %t/a/t1.o %t/b/t2.o

llvm/include/llvm/MC/MCMachOCASWriter.h

@@ -91,43 +91,6 @@ class MachOCASWriter : public MCObjectWriter {
     MOW.writeDataInCodeRegion(Asm);
   }
 
-  void setVersionMin(MCVersionMinType Type, unsigned Major, unsigned Minor,
-                     unsigned Update,
-                     VersionTuple SDKVersion = VersionTuple()) override {
-    MOW.setVersionMin(Type, Major, Minor, Update, SDKVersion);
-  }
-  void setBuildVersion(unsigned Platform, unsigned Major, unsigned Minor,
-                       unsigned Update,
-                       VersionTuple SDKVersion = VersionTuple()) override {
-    MOW.setBuildVersion(Platform, Major, Minor, Update, SDKVersion);
-  }
-  void setTargetVariantBuildVersion(unsigned Platform, unsigned Major,
-                                    unsigned Minor, unsigned Update,
-                                    VersionTuple SDKVersion) override {
-    MOW.setTargetVariantBuildVersion(Platform, Major, Minor, Update,
-                                     SDKVersion);
-  }
-
-  std::optional<unsigned> getPtrAuthABIVersion() const override {
-    return MOW.getPtrAuthABIVersion();
-  }
-  void setPtrAuthABIVersion(unsigned V) override {
-    MOW.setPtrAuthABIVersion(V);
-  }
-  bool getPtrAuthKernelABIVersion() const override {
-    return MOW.getPtrAuthKernelABIVersion();
-  }
-  void setPtrAuthKernelABIVersion(bool V) override {
-    MOW.setPtrAuthKernelABIVersion(V);
-  }
-
-  bool getSubsectionsViaSymbols() const override {
-    return MOW.getSubsectionsViaSymbols();
-  }
-  void setSubsectionsViaSymbols(bool Value) override {
-    MOW.setSubsectionsViaSymbols(Value);
-  }
-
   void writeSymbolTable(MCAssembler &Asm) { MOW.writeSymbolTable(Asm); }
 
   uint64_t writeObject(MCAssembler &Asm) override;

llvm/include/llvm/MC/MCMachObjectWriter.h

@@ -86,6 +86,12 @@ class MCMachObjectTargetWriter : public MCObjectTargetWriter {
 
 class MachObjectWriter : public MCObjectWriter {
 public:
+  struct DataRegionData {
+    MachO::DataRegionType Kind;
+    MCSymbol *Start;
+    MCSymbol *End;
+  };
+
   // A Major version of 0 indicates that no version information was supplied
   // and so the corresponding load command should not be emitted.
   using VersionInfoType = struct {
@@ -112,6 +118,11 @@ class MachObjectWriter : public MCObjectWriter {
     bool operator<(const MachSymbolData &RHS) const;
   };
 
+  struct IndirectSymbolData {
+    MCSymbol *Symbol;
+    MCSection *Section;
+  };
+
   /// The target specific Mach-O writer instance.
   std::unique_ptr<MCMachObjectTargetWriter> TargetObjectWriter;
 
@@ -132,8 +143,11 @@ class MachObjectWriter : public MCObjectWriter {
 
 private:
   DenseMap<const MCSection *, std::vector<RelAndSymbol>> Relocations;
+  std::vector<IndirectSymbolData> IndirectSymbols;
   DenseMap<const MCSection *, unsigned> IndirectSymBase;
 
+  std::vector<DataRegionData> DataRegions;
+
   SectionAddrMap SectionAddress;
 
   // List of sections in layout order. Virtual sections are after non-virtual
@@ -151,12 +165,18 @@ class MachObjectWriter : public MCObjectWriter {
 
   /// @}
 
+  // Used to communicate Linker Optimization Hint information.
+  MCLOHContainer LOHContainer;
+
   VersionInfoType VersionInfo{};
   VersionInfoType TargetVariantVersionInfo{};
 
   std::optional<unsigned> PtrAuthABIVersion;
   bool PtrAuthKernelABIVersion;
 
+  // The list of linker options for LC_LINKER_OPTION.
+  std::vector<std::vector<std::string>> LinkerOptions;
+
   MachSymbolData *findSymbolData(const MCSymbol &Sym);
 
   void writeWithPadding(StringRef Str, uint64_t Size);
@@ -194,10 +214,15 @@ class MachObjectWriter : public MCObjectWriter {
 
   bool isFixupKindPCRel(const MCAssembler &Asm, unsigned Kind);
 
+  std::vector<IndirectSymbolData> &getIndirectSymbols() {
+    return IndirectSymbols;
+  }
+  std::vector<DataRegionData> &getDataRegions() { return DataRegions; }
   const llvm::SmallVectorImpl<MCSection *> &getSectionOrder() const {
     return SectionOrder;
   }
   SectionAddrMap &getSectionAddressMap() { return SectionAddress; }
+  MCLOHContainer &getLOHContainer() { return LOHContainer; }
 
   uint64_t getSectionAddress(const MCSection *Sec) const {
     return SectionAddress.lookup(Sec);
@@ -216,45 +241,43 @@ class MachObjectWriter : public MCObjectWriter {
   /// Mach-O deployment target version information.
   void setVersionMin(MCVersionMinType Type, unsigned Major, unsigned Minor,
                      unsigned Update,
-                     VersionTuple SDKVersion = VersionTuple()) override {
+                     VersionTuple SDKVersion = VersionTuple()) {
     VersionInfo.EmitBuildVersion = false;
     VersionInfo.TypeOrPlatform.Type = Type;
     VersionInfo.Major = Major;
     VersionInfo.Minor = Minor;
     VersionInfo.Update = Update;
     VersionInfo.SDKVersion = SDKVersion;
   }
-  void setBuildVersion(unsigned Platform, unsigned Major, unsigned Minor,
-                       unsigned Update,
-                       VersionTuple SDKVersion = VersionTuple()) override {
+  void setBuildVersion(MachO::PlatformType Platform, unsigned Major,
+                       unsigned Minor, unsigned Update,
+                       VersionTuple SDKVersion = VersionTuple()) {
     VersionInfo.EmitBuildVersion = true;
-    VersionInfo.TypeOrPlatform.Platform = (MachO::PlatformType)Platform;
+    VersionInfo.TypeOrPlatform.Platform = Platform;
     VersionInfo.Major = Major;
     VersionInfo.Minor = Minor;
     VersionInfo.Update = Update;
     VersionInfo.SDKVersion = SDKVersion;
   }
-  void setTargetVariantBuildVersion(unsigned Platform, unsigned Major,
-                                    unsigned Minor, unsigned Update,
-                                    VersionTuple SDKVersion) override {
+  void setTargetVariantBuildVersion(MachO::PlatformType Platform,
+                                    unsigned Major, unsigned Minor,
+                                    unsigned Update, VersionTuple SDKVersion) {
     TargetVariantVersionInfo.EmitBuildVersion = true;
-    TargetVariantVersionInfo.TypeOrPlatform.Platform =
-        (MachO::PlatformType)Platform;
+    TargetVariantVersionInfo.TypeOrPlatform.Platform = Platform;
     TargetVariantVersionInfo.Major = Major;
     TargetVariantVersionInfo.Minor = Minor;
     TargetVariantVersionInfo.Update = Update;
     TargetVariantVersionInfo.SDKVersion = SDKVersion;
   }
 
-  std::optional<unsigned> getPtrAuthABIVersion() const override {
+  std::optional<unsigned> getPtrAuthABIVersion() const {
     return PtrAuthABIVersion;
   }
-  void setPtrAuthABIVersion(unsigned V) override { PtrAuthABIVersion = V; }
-  bool getPtrAuthKernelABIVersion() const override {
-    return PtrAuthKernelABIVersion;
-  }
-  void setPtrAuthKernelABIVersion(bool V) override {
-    PtrAuthKernelABIVersion = V;
+  void setPtrAuthABIVersion(unsigned V) { PtrAuthABIVersion = V; }
+  bool getPtrAuthKernelABIVersion() const { return PtrAuthKernelABIVersion; }
+  void setPtrAuthKernelABIVersion(bool V) { PtrAuthKernelABIVersion = V; }
+  std::vector<std::vector<std::string>> &getLinkerOptions() {
+    return LinkerOptions;
   }
 
   /// @}

llvm/include/llvm/MC/MCObjectWriter.h

@@ -9,8 +9,6 @@
 #ifndef LLVM_MC_MCOBJECTWRITER_H
 #define LLVM_MC_MCOBJECTWRITER_H
 
-#include "llvm/MC/MCDirectives.h"
-#include "llvm/MC/MCLinkerOptimizationHint.h"
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/TargetParser/Triple.h"
 #include <cstdint>
@@ -33,29 +31,7 @@ class MCValue;
 /// MCAssembler instance, which contains all the symbol and section data which
 /// should be emitted as part of writeObject().
 class MCObjectWriter {
-public:
-  struct DataRegionData {
-    unsigned Kind;
-    MCSymbol *Start;
-    MCSymbol *End;
-  };
-
 protected:
-  struct IndirectSymbolData {
-    MCSymbol *Symbol;
-    MCSection *Section;
-  };
-
-  std::vector<IndirectSymbolData> IndirectSymbols;
-
-  std::vector<DataRegionData> DataRegions;
-
-  // The list of linker options for LC_LINKER_OPTION.
-  std::vector<std::vector<std::string>> LinkerOptions;
-
-  // Used to communicate Linker Optimization Hint information.
-  MCLOHContainer LOHContainer;
-
   /// List of declared file names
   SmallVector<std::pair<std::string, size_t>, 0> FileNames;
   // XCOFF specific: Optional compiler version.
@@ -84,18 +60,6 @@ class MCObjectWriter {
   /// \name High-Level API
   /// @{
 
-  std::vector<std::vector<std::string>> &getLinkerOptions() {
-    return LinkerOptions;
-  }
-
-  std::vector<IndirectSymbolData> &getIndirectSymbols() {
-    return IndirectSymbols;
-  }
-
-  MCLOHContainer &getLOHContainer() { return LOHContainer; }
-
-  std::vector<DataRegionData> &getDataRegions() { return DataRegions; }
-
   /// Perform any late binding of symbols (for example, to assign symbol
   /// indices for use when generating relocations).
   ///
@@ -152,12 +116,8 @@ class MCObjectWriter {
   SmallVector<CGProfileEntry, 0> &getCGProfile() { return CGProfile; }
 
   // Mach-O specific: Whether .subsections_via_symbols is enabled.
-  virtual bool getSubsectionsViaSymbols() const {
-    return SubsectionsViaSymbols;
-  }
-  virtual void setSubsectionsViaSymbols(bool Value) {
-    SubsectionsViaSymbols = Value;
-  }
+  bool getSubsectionsViaSymbols() const { return SubsectionsViaSymbols; }
+  void setSubsectionsViaSymbols(bool Value) { SubsectionsViaSymbols = Value; }
 
   /// Write the object file and returns the number of bytes written.
   ///
@@ -166,22 +126,6 @@ class MCObjectWriter {
   /// generated.
   virtual uint64_t writeObject(MCAssembler &Asm) = 0;
 
-  virtual void setVersionMin(MCVersionMinType Type, unsigned Major,
-                             unsigned Minor, unsigned Update,
-                             VersionTuple SDKVersion = VersionTuple()) {}
-  virtual void setBuildVersion(unsigned Platform, unsigned Major,
-                               unsigned Minor, unsigned Update,
-                               VersionTuple SDKVersion = VersionTuple()) {}
-
-  virtual void setTargetVariantBuildVersion(unsigned Platform, unsigned Major,
-                                            unsigned Minor, unsigned Update,
-                                            VersionTuple SDKVersion) {}
-  virtual std::optional<unsigned> getPtrAuthABIVersion() const {
-    return std::nullopt;
-  }
-  virtual void setPtrAuthABIVersion(unsigned V) {}
-  virtual bool getPtrAuthKernelABIVersion() const { return false; }
-  virtual void setPtrAuthKernelABIVersion(bool V) {}
   /// @}
 };
 

llvm/include/llvm/MC/MCSPIRVObjectWriter.h

@@ -45,10 +45,6 @@ class SPIRVObjectWriter final : public MCObjectWriter {
 
   void setBuildVersion(unsigned Major, unsigned Minor, unsigned Bound);
 
-  void setBuildVersion(unsigned Platform, unsigned Major, unsigned Minor,
-                       unsigned Update,
-                       VersionTuple SDKVersion = VersionTuple()) override {}
-
 private:
   void recordRelocation(MCAssembler &Asm, const MCFragment *Fragment,
                         const MCFixup &Fixup, MCValue Target,