Don't pass the code model to MC

[• rafael]

Summary

I was surprised to see the code model being passed to MC. After all, it assembles code, it doesn't create it.

The one place it is used is in the expansion of .cfi directives to handle .eh_frame being more that 2gb away from the code.

As far as I can tell, gnu assembler doesn't even have an option to enable this. Compiling a c file with gcc -mcmodel=large produces a regular looking .eh_frame. This is probably because in practice linker parse and recreate .eh_frames.

In llvm this is used because the JIT can place the code and .eh_frame very far apart. Ideally we would fix the jit and delete this option. This is hard.

Apart from confusion another problem with the current interface is that most callers pass CodeModel::Default, which is bad since MC has no way to map it to the target default if it actually needed to.

This patch then replaces the argument with a boolean with a default value. The vast majority of users don't ever need to look at it. In fact, only CodeGen and llvm-mc use it and llvm-mc just to enable more testing.

[davide]

LGTM. Excellent catch Rafael. I find amusing in retrospective we all looked at this code for years without noticing.

[lliu0]

Hi Rafael,

This change caused a regression with -mcmodel=kernel. In several places of lib/MC/MCObjectFileInfo.cpp, the logic changed from
(CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
to
(!CMModel == CodeModel::Large)
which changes the behavior of CodeModel::Kernel case.

While I do agree that we shouldn't pass CodeModel command line option to llvm-mc, but in MCObjectFileInfo::InitMCObjectFileInfo, it looks that we still need a full CodeModel parameter to generate different x86_64 exception table encodings for different code models.

I can start a review for this if you agree.

Thanks,
Lei

include/llvm/MC/MCObjectFileInfo.h

protected:
 
   /// COFF specific sections.
   MCSection *DrectveSection;
   MCSection *PDataSection;
   MCSection *XDataSection;
   MCSection *SXDataSection;
 
 public:
-  void InitMCObjectFileInfo(const Triple &TT, bool PIC, CodeModel::Model CM,
-                            MCContext &ctx);
+  void InitMCObjectFileInfo(const Triple &TT, bool PIC, MCContext &ctx,
+                            bool LargeCodeModel = false);
 
   bool getSupportsWeakOmittedEHFrame() const {
     return SupportsWeakOmittedEHFrame;
   }
   bool getSupportsCompactUnwindWithoutEHFrame() const {
     return SupportsCompactUnwindWithoutEHFrame;
   }
   bool getOmitDwarfIfHaveCompactUnwind() const {
public:
   enum Environment { IsMachO, IsELF, IsCOFF, IsWasm };
   Environment getObjectFileType() const { return Env; }
 
   bool isPositionIndependent() const { return PositionIndependent; }
 
 private:
   Environment Env;
   bool PositionIndependent;
-  CodeModel::Model CMModel;
   MCContext *Ctx;
   Triple TT;
 
   void initMachOMCObjectFileInfo(const Triple &T);
-  void initELFMCObjectFileInfo(const Triple &T);
+  void initELFMCObjectFileInfo(const Triple &T, bool Large);
   void initCOFFMCObjectFileInfo(const Triple &T);
   void initWasmMCObjectFileInfo(const Triple &T);
 
 public:
   const Triple &getTargetTriple() const { return TT; }
 };
 
 } // end namespace llvm
 
 #endif

lib/MC/MCObjectFileInfo.cpp

StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps",
                                          0, SectionKind::getMetadata());
 
   FaultMapSection = Ctx->getMachOSection("__LLVM_FAULTMAPS", "__llvm_faultmaps",
                                          0, SectionKind::getMetadata());
 
   TLSExtraDataSection = TLSTLVSection;
 }
 
-void MCObjectFileInfo::initELFMCObjectFileInfo(const Triple &T) {
+void MCObjectFileInfo::initELFMCObjectFileInfo(const Triple &T, bool Large) {
   switch (T.getArch()) {
   case Triple::mips:
   case Triple::mipsel:
     FDECFIEncoding = dwarf::DW_EH_PE_sdata4;
     break;
   case Triple::mips64:
   case Triple::mips64el:
     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
     break;
   case Triple::x86_64:
     FDECFIEncoding = dwarf::DW_EH_PE_pcrel |
-                     ((CMModel == CodeModel::Large) ? dwarf::DW_EH_PE_sdata8
-                                                    : dwarf::DW_EH_PE_sdata4);
+                     (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;
LSDAEncoding = PositionIndependent
                        : 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 |
-        ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
-         ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
+      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 |
-        (CMModel == CodeModel::Small
-         ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
+                     (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
-         ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
+                      (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
     } else {
       PersonalityEncoding =
-        (CMModel == CodeModel::Small || CMModel == CodeModel::Medium)
-        ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
-      LSDAEncoding = (CMModel == CodeModel::Small)
-        ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
-      TTypeEncoding = (CMModel == CodeModel::Small)
-        ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
+          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) {
void MCObjectFileInfo::initWasmMCObjectFileInfo(const Triple &T) {
   DwarfFrameSection = Ctx->getWasmSection(".debug_frame", 0, 0);
   DwarfPubNamesSection = Ctx->getWasmSection(".debug_pubnames", 0, 0);
   DwarfPubTypesSection = Ctx->getWasmSection(".debug_pubtypes", 0, 0);
 
   // TODO: Define more sections.
 }
 
 void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple, bool PIC,
-                                            CodeModel::Model cm,
-                                            MCContext &ctx) {
+                                            MCContext &ctx,
+                                            bool LargeCodeModel) {
   PositionIndependent = PIC;
-  CMModel = cm;
   Ctx = &ctx;
 
   // Common.
   CommDirectiveSupportsAlignment = true;
   SupportsWeakOmittedEHFrame = true;
   SupportsCompactUnwindWithoutEHFrame = false;
   OmitDwarfIfHaveCompactUnwind = false;
 
if (!TT.isOSWindows())
       report_fatal_error(
           "Cannot initialize MC for non-Windows COFF object files.");
 
     Env = IsCOFF;
     initCOFFMCObjectFileInfo(TT);
     break;
   case Triple::ELF:
     Env = IsELF;
-    initELFMCObjectFileInfo(TT);
+    initELFMCObjectFileInfo(TT, LargeCodeModel);
     break;
   case Triple::Wasm:
     Env = IsWasm;
     initWasmMCObjectFileInfo(TT);
     break;
   case Triple::UnknownObjectFormat:
     report_fatal_error("Cannot initialize MC for unknown object file format.");
     break;
   }
 }
 
 MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const {
   return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP,
                             0, utostr(Hash));
 }

lib/Object/ModuleSymbolTable.cpp

if (!STI)
     return;
 
   std::unique_ptr<MCInstrInfo> MCII(T->createMCInstrInfo());
   if (!MCII)
     return;
 
   MCObjectFileInfo MOFI;
   MCContext MCCtx(MAI.get(), MRI.get(), &MOFI);
-  MOFI.InitMCObjectFileInfo(TT, /*PIC*/ false, CodeModel::Default, MCCtx);
+  MOFI.InitMCObjectFileInfo(TT, /*PIC*/ false, MCCtx);
   RecordStreamer Streamer(MCCtx);
   T->createNullTargetStreamer(Streamer);
 
   std::unique_ptr<MemoryBuffer> Buffer(MemoryBuffer::getMemBuffer(InlineAsm));
   SourceMgr SrcMgr;
   SrcMgr.AddNewSourceBuffer(std::move(Buffer), SMLoc());
   std::unique_ptr<MCAsmParser> Parser(
       createMCAsmParser(SrcMgr, MCCtx, Streamer, *MAI));

lib/Target/TargetLoweringObjectFile.cpp

 /// done.  This specifies the current context for codegen, and gives the
 /// lowering implementations a chance to set up their default sections.
 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(),
-                       TM.getCodeModel(), *Ctx);
+  InitMCObjectFileInfo(TM.getTargetTriple(), TM.isPositionIndependent(), *Ctx,
+                       TM.getCodeModel() == CodeModel::Large);
 }
 
 TargetLoweringObjectFile::~TargetLoweringObjectFile() {
   delete Mang;
 }
 
 static bool isSuitableForBSS(const GlobalVariable *GV, bool NoZerosInBSS) {
   const Constant *C = GV->getInitializer();

test/ExecutionEngine/RuntimeDyld/AArch64/MachO_ARM64_relocations.s

-# RUN: llvm-mc -triple=arm64-apple-ios7.0.0 -code-model=small -filetype=obj -o %T/foo.o %s
+# RUN: llvm-mc -triple=arm64-apple-ios7.0.0 -filetype=obj -o %T/foo.o %s
 # RUN: llvm-rtdyld -triple=arm64-apple-ios7.0.0 -map-section foo.o,__text=0x10bc0 -verify -check=%s %/T/foo.o
 
     .section  __TEXT,__text,regular,pure_instructions
     .ios_version_min 7, 0
     .globl  _foo
     .align  2
 _foo:
     movz  w0, #0

test/ExecutionEngine/RuntimeDyld/Mips/ELF_Mips64r2N64_PIC_relocations.s

-# RUN: llvm-mc -triple=mips64el-unknown-linux -code-model=small -filetype=obj -o %T/test_ELF_Mips64N64.o %s
+# RUN: llvm-mc -triple=mips64el-unknown-linux -filetype=obj -o %T/test_ELF_Mips64N64.o %s
 # RUN: llc -mtriple=mips64el-unknown-linux -filetype=obj -o %T/test_ELF_ExternalFunction_Mips64N64.o %S/Inputs/ExternalFunction.ll
 # RUN: llvm-rtdyld -triple=mips64el-unknown-linux -verify -map-section test_ELF_Mips64N64.o,.text=0x1000 -map-section test_ELF_ExternalFunction_Mips64N64.o,.text=0x10000 -check=%s %/T/test_ELF_Mips64N64.o %T/test_ELF_ExternalFunction_Mips64N64.o
 
-# RUN: llvm-mc -triple=mips64-unknown-linux -code-model=small -filetype=obj -o %T/test_ELF_Mips64N64.o %s
+# RUN: llvm-mc -triple=mips64-unknown-linux -filetype=obj -o %T/test_ELF_Mips64N64.o %s
 # RUN: llc -mtriple=mips64-unknown-linux -filetype=obj -o %T/test_ELF_ExternalFunction_Mips64N64.o %S/Inputs/ExternalFunction.ll
 # RUN: llvm-rtdyld -triple=mips64-unknown-linux -verify -map-section test_ELF_Mips64N64.o,.text=0x1000 -map-section test_ELF_ExternalFunction_Mips64N64.o,.text=0x10000 -check=%s %/T/test_ELF_Mips64N64.o %T/test_ELF_ExternalFunction_Mips64N64.o
 
   .data
 # Test R_MIPS_PC32 relocation.
 # rtdyld-check: *{4}(R_MIPS_PC32) = (foo - R_MIPS_PC32)[31:0]
 R_MIPS_PC32:
   .word foo-.

test/ExecutionEngine/RuntimeDyld/Mips/ELF_N32_relocations.s

-# RUN: llvm-mc -triple=mips64el-unknown-linux -target-abi n32 -code-model=small -filetype=obj -o %T/test_ELF_N32.o %s
+# RUN: llvm-mc -triple=mips64el-unknown-linux -target-abi n32 -filetype=obj -o %T/test_ELF_N32.o %s
 # RUN: llc -mtriple=mips64el-unknown-linux -target-abi n32 -filetype=obj -o %T/test_ELF_ExternalFunction_N32.o %S/Inputs/ExternalFunction.ll
 # RUN: llvm-rtdyld -triple=mips64el-unknown-linux -verify -map-section test_ELF_N32.o,.text=0x1000 -map-section test_ELF_ExternalFunction_N32.o,.text=0x10000 -check=%s %/T/test_ELF_N32.o %T/test_ELF_ExternalFunction_N32.o
 
-# RUN: llvm-mc -triple=mips64-unknown-linux -target-abi n32 -code-model=small -filetype=obj -o %T/test_ELF_N32.o %s
+# RUN: llvm-mc -triple=mips64-unknown-linux -target-abi n32 -filetype=obj -o %T/test_ELF_N32.o %s
 # RUN: llc -mtriple=mips64-unknown-linux -target-abi n32 -filetype=obj -o %T/test_ELF_ExternalFunction_N32.o %S/Inputs/ExternalFunction.ll
 # RUN: llvm-rtdyld -triple=mips64-unknown-linux -verify -map-section test_ELF_N32.o,.text=0x1000 -map-section test_ELF_ExternalFunction_N32.o,.text=0x10000 -check=%s %/T/test_ELF_N32.o %T/test_ELF_ExternalFunction_N32.o
 
   .data
 # Test R_MIPS_PC32 relocation.
 # rtdyld-check: *{4}(R_MIPS_PC32) = (foo - R_MIPS_PC32)[31:0]
 R_MIPS_PC32:
   .word foo-.

test/ExecutionEngine/RuntimeDyld/Mips/ELF_N64R6_relocations.s

-# RUN: llvm-mc -triple=mips64el-unknown-linux -mcpu=mips64r6 -code-model=small -filetype=obj -o %T/test_ELF_N64R6.o %s
+# RUN: llvm-mc -triple=mips64el-unknown-linux -mcpu=mips64r6 -filetype=obj -o %T/test_ELF_N64R6.o %s
 # RUN: llc -mtriple=mips64el-unknown-linux -mcpu=mips64r6 -filetype=obj -o %T/test_ELF_ExternalFunction_N64R6.o %S/Inputs/ExternalFunction.ll
 # RUN: llvm-rtdyld -triple=mips64el-unknown-linux -mcpu=mips64r6 -verify -map-section test_ELF_N64R6.o,.text=0x1000 -map-section test_ELF_ExternalFunction_N64R6.o,.text=0x10000 -check=%s %/T/test_ELF_N64R6.o %T/test_ELF_ExternalFunction_N64R6.o
 
-# RUN: llvm-mc -triple=mips64-unknown-linux -mcpu=mips64r6 -code-model=small -filetype=obj -o %T/test_ELF_N64R6.o %s
+# RUN: llvm-mc -triple=mips64-unknown-linux -mcpu=mips64r6 -filetype=obj -o %T/test_ELF_N64R6.o %s
 # RUN: llc -mtriple=mips64-unknown-linux -mcpu=mips64r6 -filetype=obj -o %T/test_ELF_ExternalFunction_N64R6.o %S/Inputs/ExternalFunction.ll
 # RUN: llvm-rtdyld -triple=mips64-unknown-linux -mcpu=mips64r6 -verify -map-section test_ELF_N64R6.o,.text=0x1000 -map-section test_ELF_ExternalFunction_N64R6.o,.text=0x10000 -check=%s %/T/test_ELF_N64R6.o %T/test_ELF_ExternalFunction_N64R6.o
 
   .text
   .abicalls
   .nan  2008
   .text
   .set  nomicromips

test/ExecutionEngine/RuntimeDyld/Mips/ELF_O32R6_relocations.s

-# RUN: llvm-mc -triple=mipsel-unknown-linux -mcpu=mips32r6 -code-model=small -filetype=obj -o %T/test_ELF_O32R6.o %s
+# RUN: llvm-mc -triple=mipsel-unknown-linux -mcpu=mips32r6 -filetype=obj -o %T/test_ELF_O32R6.o %s
 # RUN: llc -mtriple=mipsel-unknown-linux -mcpu=mips32r6 -filetype=obj -o %T/test_ELF_ExternalFunction_O32R6.o %S/Inputs/ExternalFunction.ll
 # RUN: llvm-rtdyld -triple=mipsel-unknown-linux -mcpu=mips32r6 -verify -map-section test_ELF_O32R6.o,.text=0x1000 -map-section test_ELF_ExternalFunction_O32R6.o,.text=0x10000 -check=%s %/T/test_ELF_O32R6.o %T/test_ELF_ExternalFunction_O32R6.o
 
-# RUN: llvm-mc -triple=mips-unknown-linux -mcpu=mips32r6 -code-model=small -filetype=obj -o %T/test_ELF_O32R6.o %s
+# RUN: llvm-mc -triple=mips-unknown-linux -mcpu=mips32r6 -filetype=obj -o %T/test_ELF_O32R6.o %s
 # RUN: llc -mtriple=mips-unknown-linux -mcpu=mips32r6 -filetype=obj -o %T/test_ELF_ExternalFunction_O32R6.o %S/Inputs/ExternalFunction.ll
 # RUN: llvm-rtdyld -triple=mips-unknown-linux -mcpu=mips32r6 -verify -map-section test_ELF_O32R6.o,.text=0x1000 -map-section test_ELF_ExternalFunction_O32R6.o,.text=0x10000 -check=%s %/T/test_ELF_O32R6.o %T/test_ELF_ExternalFunction_O32R6.o
 
   .text
   .abicalls
   .nan  2008
   .text
   .set  nomicromips

test/ExecutionEngine/RuntimeDyld/Mips/ELF_O32_PIC_relocations.s

-# RUN: llvm-mc -triple=mipsel-unknown-linux -code-model=small -filetype=obj -o %T/test_ELF_O32.o %s
+# RUN: llvm-mc -triple=mipsel-unknown-linux -filetype=obj -o %T/test_ELF_O32.o %s
 # RUN: llc -mtriple=mipsel-unknown-linux -filetype=obj -o %T/test_ELF_ExternalFunction_O32.o %S/Inputs/ExternalFunction.ll
 # RUN: llvm-rtdyld -triple=mipsel-unknown-linux -verify -map-section test_ELF_O32.o,"<common symbols>"=0x7FF8 -map-section test_ELF_O32.o,.text=0x1000 -map-section test_ELF_ExternalFunction_O32.o,.text=0x10000 -check=%s %T/test_ELF_O32.o %T/test_ELF_ExternalFunction_O32.o
 
-# RUN: llvm-mc -triple=mips-unknown-linux -code-model=small -filetype=obj -o %T/test_ELF_O32.o %s
+# RUN: llvm-mc -triple=mips-unknown-linux -filetype=obj -o %T/test_ELF_O32.o %s
 # RUN: llc -mtriple=mips-unknown-linux -filetype=obj -o %/T/test_ELF_ExternalFunction_O32.o %S/Inputs/ExternalFunction.ll
 # RUN: llvm-rtdyld -triple=mips-unknown-linux -verify -map-section test_ELF_O32.o,"<common symbols>"=0x7FF8 -map-section test_ELF_O32.o,.text=0x1000 -map-section test_ELF_ExternalFunction_O32.o,.text=0x10000 -check=%s %T/test_ELF_O32.o %T/test_ELF_ExternalFunction_O32.o
 
         .data
 # rtdyld-check: *{4}R_MIPS_32 = foo[31:0]
 R_MIPS_32:
         .word foo
 # rtdyld-check: *{4}(R_MIPS_32+4) = foo[31:0]

test/ExecutionEngine/RuntimeDyld/X86/ELF_x86-64_PIC-small-relocations.s

-# RUN: llvm-mc -triple=x86_64-unknown-freebsd -code-model=small -filetype=obj -o %T/testsmall_x86-64.o %s
+# RUN: llvm-mc -triple=x86_64-unknown-freebsd -filetype=obj -o %T/testsmall_x86-64.o %s
 # RUN: llvm-rtdyld -triple=x86_64-unknown-freebsd -verify -check=%s %/T/testsmall_x86-64.o
 
   .globl  foo
   .align  4, 0x90
 foo:
         retq
 
   .globl  main
   .align  4, 0x90
 main:
 # Test PC-rel branch.
 # rtdyld-check: decode_operand(insn1, 0) = foo - next_pc(insn1)
 insn1:
         callq foo

test/MC/ELF/cfi-large-model.s

-// RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu -code-model=large %s \
+// RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu -large-code-model %s \
 // RUN:   -o - | llvm-readobj -s -sd | FileCheck %s
 
 // CHECK:      Section {
 // CHECK:        Index: 
 // CHECK:        Name: .eh_frame
 // CHECK-NEXT:   Type: SHT_X86_64_UNWIND
 // CHECK-NEXT:   Flags [
 // CHECK-NEXT:     SHF_ALLOC

tools/dsymutil/DwarfLinker.cpp

if (!MRI)
     return error(Twine("no register info for target ") + TripleName, Context);
 
   MAI.reset(TheTarget->createMCAsmInfo(*MRI, TripleName));
   if (!MAI)
     return error("no asm info for target " + TripleName, Context);
 
   MOFI.reset(new MCObjectFileInfo);
   MC.reset(new MCContext(MAI.get(), MRI.get(), MOFI.get()));
-  MOFI->InitMCObjectFileInfo(TheTriple, /*PIC*/ false, CodeModel::Default, *MC);
+  MOFI->InitMCObjectFileInfo(TheTriple, /*PIC*/ false, *MC);
 
   MCTargetOptions Options;
   MAB = TheTarget->createMCAsmBackend(*MRI, TripleName, "", Options);
   if (!MAB)
     return error("no asm backend for target " + TripleName, Context);
 
   MII.reset(TheTarget->createMCInstrInfo());
   if (!MII)

tools/llvm-dwp/llvm-dwp.cpp

if (!MRI)
     return error(Twine("no register info for target ") + TripleName, Context);
 
   std::unique_ptr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, TripleName));
   if (!MAI)
     return error("no asm info for target " + TripleName, Context);
 
   MCObjectFileInfo MOFI;
   MCContext MC(MAI.get(), MRI.get(), &MOFI);
-  MOFI.InitMCObjectFileInfo(TheTriple, /*PIC*/ false, CodeModel::Default, MC);
+  MOFI.InitMCObjectFileInfo(TheTriple, /*PIC*/ false, MC);
 
   MCTargetOptions Options;
   auto MAB = TheTarget->createMCAsmBackend(*MRI, TripleName, "", Options);
   if (!MAB)
     return error("no asm backend for target " + TripleName, Context);
 
   std::unique_ptr<MCInstrInfo> MII(TheTarget->createMCInstrInfo());
   if (!MII)

tools/llvm-mc/llvm-mc.cpp

 MAttrs("mattr",
   cl::CommaSeparated,
   cl::desc("Target specific attributes (-mattr=help for details)"),
   cl::value_desc("a1,+a2,-a3,..."));
 
 static cl::opt<bool> PIC("position-independent",
                          cl::desc("Position independent"), cl::init(false));
 
-static cl::opt<llvm::CodeModel::Model>
-CMModel("code-model",
-        cl::desc("Choose code model"),
-        cl::init(CodeModel::Default),
-        cl::values(clEnumValN(CodeModel::Default, "default",
-                              "Target default code model"),
-                   clEnumValN(CodeModel::Small, "small",
-                              "Small code model"),
-                   clEnumValN(CodeModel::Kernel, "kernel",
-                              "Kernel code model"),
-                   clEnumValN(CodeModel::Medium, "medium",
-                              "Medium code model"),
-                   clEnumValN(CodeModel::Large, "large",
-                              "Large code model")));
+static cl::opt<bool>
+    LargeCodeModel("large-code-model",
+                   cl::desc("Create cfi directives that assume the code might "
+                            "be more than 2gb away"));
 
 static cl::opt<bool>
 NoInitialTextSection("n", cl::desc("Don't assume assembly file starts "
                                    "in the text section"));
 
 static cl::opt<bool>
 GenDwarfForAssembly("g", cl::desc("Generate dwarf debugging info for assembly "
                                   "source files"));
if (CompressDebugSections != DebugCompressionType::None) {
     MAI->setCompressDebugSections(CompressDebugSections);
   }
   MAI->setPreserveAsmComments(PreserveComments);
 
   // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
   // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
   MCObjectFileInfo MOFI;
   MCContext Ctx(MAI.get(), MRI.get(), &MOFI, &SrcMgr);
-  MOFI.InitMCObjectFileInfo(TheTriple, PIC, CMModel, Ctx);
+  MOFI.InitMCObjectFileInfo(TheTriple, PIC, Ctx, LargeCodeModel);
 
   if (SaveTempLabels)
     Ctx.setAllowTemporaryLabels(false);
 
   Ctx.setGenDwarfForAssembly(GenDwarfForAssembly);
   // Default to 4 for dwarf version.
   unsigned DwarfVersion = MCOptions.DwarfVersion ? MCOptions.DwarfVersion : 4;
   if (DwarfVersion < 2 || DwarfVersion > 5) {

tools/llvm-objdump/llvm-objdump.cpp

report_error(Obj->getFileName(), "no subtarget info for target " +
                  TripleName);
   std::unique_ptr<const MCInstrInfo> MII(TheTarget->createMCInstrInfo());
   if (!MII)
     report_error(Obj->getFileName(), "no instruction info for target " +
                  TripleName);
   MCObjectFileInfo MOFI;
   MCContext Ctx(AsmInfo.get(), MRI.get(), &MOFI);
   // FIXME: for now initialize MCObjectFileInfo with default values
-  MOFI.InitMCObjectFileInfo(Triple(TripleName), false, CodeModel::Default, Ctx);
+  MOFI.InitMCObjectFileInfo(Triple(TripleName), false, Ctx);
 
   std::unique_ptr<MCDisassembler> DisAsm(
     TheTarget->createMCDisassembler(*STI, Ctx));
   if (!DisAsm)
     report_error(Obj->getFileName(), "no disassembler for target " +
                  TripleName);
 
   std::unique_ptr<const MCInstrAnalysis> MIA(

unittests/DebugInfo/DWARF/DwarfGenerator.cpp

llvm::Error dwarfgen::Generator::init(Triple TheTriple, uint16_t V) {
 
   MAI.reset(TheTarget->createMCAsmInfo(*MRI, TripleName));
   if (!MAI)
     return make_error<StringError>("no asm info for target " + TripleName,
                                    inconvertibleErrorCode());
 
   MOFI.reset(new MCObjectFileInfo);
   MC.reset(new MCContext(MAI.get(), MRI.get(), MOFI.get()));
-  MOFI->InitMCObjectFileInfo(TheTriple, /*PIC*/ false, CodeModel::Default, *MC);
+  MOFI->InitMCObjectFileInfo(TheTriple, /*PIC*/ false, *MC);
 
   MCTargetOptions Options;
   MAB = TheTarget->createMCAsmBackend(*MRI, TripleName, "", Options);
   if (!MAB)
     return make_error<StringError>("no asm backend for target " + TripleName,
                                    inconvertibleErrorCode());
 
   MII.reset(TheTarget->createMCInstrInfo());