Properly pass through the PIC mode to the integrated assembler when doing assembly-only, and unify the Driver's PIC argument parsing.

[jyknight]

Summary

On a few architectures, parsing of assembly files annoyingly depends
on whether PIC is enabled or not. This was handled for external 'as'
already (passing -KPIC), but was missed for calls to the standalone
internal assembler.

The integrated-as.s test needed to be modified to not expect
-fsanitize=address to be unused, as now fsanitize *IS* used for
assembly, since -fsanitize=memory can sometimes imply -fPIE, which the
assembler needs to know (gack!!).

[joerg]

I agree in principle. The "-static" thing is already in the initial code, but doesn't make sense to me.

lib/Driver/Tools.cpp

2928

Drop the last with?

2930

Not a native speaker, but "returns as tuple" sounds more natural?

Why is the PICLevel signed?

2998

No need to rant about GCC behavior that much. Just state that older GCC versions provided different (inconsistent behavior).

3022

Difficult to parse. Please rewrite the second sentence.

3032

This check doesn't make sense to me. When using just -S, -static is completely ignored. So why should it be relevant here?

3083

This part looks like a clean up that can be applied separately first?

[jyknight]

Updated for review comments

lib/Driver/Tools.cpp

2928

Done.

2930

It's signed because I just used 'int' as a default; doesn't seem like it makes a difference, but made it unsigned.

2998

I don't think it's even worth saying that much -- the original comment was from 2012, and isn't really relevant information to anyone reading this. Removed.

3022

Done.

3032

Not sure what you mean? This code isn't only used with -S -- it's used for all clang compile and assemble actions.

3083

Committed separately as r245154.

[jyknight]

Joerg said LGTM on #llvm; going ahead with commit.

include/clang/Driver/CC1Options.td

 def massembler_fatal_warnings : Flag<["-"], "massembler-fatal-warnings">,
   HelpText<"Make assembler warnings fatal">;
 def compress_debug_sections : Flag<["-"], "compress-debug-sections">,
     HelpText<"Compress DWARF debug sections using zlib">;
 def msave_temp_labels : Flag<["-"], "msave-temp-labels">,
   HelpText<"Save temporary labels in the symbol table. "
            "Note this may change .s semantics and shouldn't generally be used "
            "on compiler-generated code.">;
-
+def mrelocation_model : Separate<["-"], "mrelocation-model">,
+  HelpText<"The relocation model to use">;
 }
 
 def disable_llvm_optzns : Flag<["-"], "disable-llvm-optzns">,
   HelpText<"Don't run LLVM optimization passes">;
 def disable_llvm_verifier : Flag<["-"], "disable-llvm-verifier">,
   HelpText<"Don't run the LLVM IR verifier pass">;
 def disable_llvm_passes : Flag<["-"], "disable-llvm-passes">,
   HelpText<"Use together with -emit-llvm to get pristine LLVM IR from the "

 def split_stacks : Flag<["-"], "split-stacks">,
   HelpText<"Try to use a split stack if possible.">;
 def mno_zero_initialized_in_bss : Flag<["-"], "mno-zero-initialized-in-bss">,
   HelpText<"Do not put zero initialized data in the BSS">;
 def backend_option : Separate<["-"], "backend-option">,
   HelpText<"Additional arguments to forward to LLVM backend (during code gen)">;
 def mregparm : Separate<["-"], "mregparm">,
   HelpText<"Limit the number of registers available for integer arguments">;
-def mrelocation_model : Separate<["-"], "mrelocation-model">,
-  HelpText<"The relocation model to use">;
 def munwind_tables : Flag<["-"], "munwind-tables">,
   HelpText<"Generate unwinding tables for all functions">;
 def mconstructor_aliases : Flag<["-"], "mconstructor-aliases">,
   HelpText<"Emit complete constructors and destructors as aliases when possible">;
 def mlink_bitcode_file : Separate<["-"], "mlink-bitcode-file">,
   HelpText<"Link the given bitcode file before performing optimizations.">;
 def vectorize_loops : Flag<["-"], "vectorize-loops">,
   HelpText<"Run the Loop vectorization passes">;

lib/Driver/Tools.cpp

 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringSwitch.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/Option.h"
-#include "llvm/Support/TargetParser.h"
+#include "llvm/Support/CodeGen.h"
 #include "llvm/Support/Compression.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Host.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Program.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/TargetParser.h"
 
 #ifdef LLVM_ON_UNIX
 #include <unistd.h> // For getuid().
 #endif
 
 using namespace clang::driver;
 using namespace clang::driver::tools;
 using namespace clang;
 using namespace llvm::opt;
 
-static void addAssemblerKPIC(const ArgList &Args, ArgStringList &CmdArgs) {
-  Arg *LastPICArg = Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,
-                                    options::OPT_fpic, options::OPT_fno_pic,
-                                    options::OPT_fPIE, options::OPT_fno_PIE,
-                                    options::OPT_fpie, options::OPT_fno_pie);
-  if (!LastPICArg)
-    return;
-  if (LastPICArg->getOption().matches(options::OPT_fPIC) ||
-      LastPICArg->getOption().matches(options::OPT_fpic) ||
-      LastPICArg->getOption().matches(options::OPT_fPIE) ||
-      LastPICArg->getOption().matches(options::OPT_fpie)) {
-    CmdArgs.push_back("-KPIC");
-  }
-}
-
 /// CheckPreprocessingOptions - Perform some validation of preprocessing
 /// arguments that is shared with gcc.
 static void CheckPreprocessingOptions(const Driver &D, const ArgList &Args) {
   if (Arg *A = Args.getLastArg(options::OPT_C, options::OPT_CC)) {
     if (!Args.hasArg(options::OPT_E) && !Args.hasArg(options::OPT__SLASH_P) &&
         !Args.hasArg(options::OPT__SLASH_EP) && !D.CCCIsCPP()) {
       D.Diag(diag::err_drv_argument_only_allowed_with)
           << A->getBaseArg().getAsString(Args)
if (Output.isFilename()) {
           CoverageFilename.swap(Pwd);
         }
       }
       CmdArgs.push_back(Args.MakeArgString(CoverageFilename));
     }
   }
 }
 
+/// Parses the various -fpic/-fPIC/-fpie/-fPIE arguments.  Then,
+/// smooshes them together with platform defaults, to decide whether
+/// this compile should be using PIC mode or not. Returns a tuple of
+/// (RelocationModel, PICLevel, IsPIE).
+static std::tuple<llvm::Reloc::Model, unsigned, bool>
+ParsePICArgs(const ToolChain &ToolChain, const llvm::Triple &Triple,
+             const ArgList &Args) {
+  // FIXME: why does this code...and so much everywhere else, use both
+  // ToolChain.getTriple() and Triple?
+  bool PIE = ToolChain.isPIEDefault();
+  bool PIC = PIE || ToolChain.isPICDefault();
+  bool IsPICLevelTwo = PIC;
+
+  bool KernelOrKext =
+      Args.hasArg(options::OPT_mkernel, options::OPT_fapple_kext);
+
+  // Android-specific defaults for PIC/PIE
+  if (ToolChain.getTriple().getEnvironment() == llvm::Triple::Android) {
+    switch (ToolChain.getArch()) {
+    case llvm::Triple::arm:
+    case llvm::Triple::armeb:
+    case llvm::Triple::thumb:
+    case llvm::Triple::thumbeb:
+    case llvm::Triple::aarch64:
+    case llvm::Triple::mips:
+    case llvm::Triple::mipsel:
+    case llvm::Triple::mips64:
+    case llvm::Triple::mips64el:
+      PIC = true; // "-fpic"
+      break;
+
+    case llvm::Triple::x86:
+    case llvm::Triple::x86_64:
+      PIC = true; // "-fPIC"
+      IsPICLevelTwo = true;
+      break;
+
+    default:
+      break;
+    }
+  }
+
+  // OpenBSD-specific defaults for PIE
+  if (ToolChain.getTriple().getOS() == llvm::Triple::OpenBSD) {
+    switch (ToolChain.getArch()) {
+    case llvm::Triple::mips64:
+    case llvm::Triple::mips64el:
+    case llvm::Triple::sparcel:
+    case llvm::Triple::x86:
+    case llvm::Triple::x86_64:
+      IsPICLevelTwo = false; // "-fpie"
+      break;
+
+    case llvm::Triple::ppc:
+    case llvm::Triple::sparc:
+    case llvm::Triple::sparcv9:
+      IsPICLevelTwo = true; // "-fPIE"
+      break;
+
+    default:
+      break;
+    }
+  }
+
+  // The last argument relating to either PIC or PIE wins, and no
+  // other argument is used. If the last argument is any flavor of the
+  // '-fno-...' arguments, both PIC and PIE are disabled. Any PIE
+  // option implicitly enables PIC at the same level.
+  Arg *LastPICArg = Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,
+                                    options::OPT_fpic, options::OPT_fno_pic,
+                                    options::OPT_fPIE, options::OPT_fno_PIE,
+                                    options::OPT_fpie, options::OPT_fno_pie);
+  // Check whether the tool chain trumps the PIC-ness decision. If the PIC-ness
+  // is forced, then neither PIC nor PIE flags will have no effect.
+  if (!ToolChain.isPICDefaultForced()) {
+    if (LastPICArg) {
+      Option O = LastPICArg->getOption();
+      if (O.matches(options::OPT_fPIC) || O.matches(options::OPT_fpic) ||
+          O.matches(options::OPT_fPIE) || O.matches(options::OPT_fpie)) {
+        PIE = O.matches(options::OPT_fPIE) || O.matches(options::OPT_fpie);
+        PIC =
+            PIE || O.matches(options::OPT_fPIC) || O.matches(options::OPT_fpic);
+        IsPICLevelTwo =
+            O.matches(options::OPT_fPIE) || O.matches(options::OPT_fPIC);
+      } else {
+        PIE = PIC = false;
+      }
+    }
+  }
+
+  // Introduce a Darwin-specific hack. If the default is PIC, but the
+  // PIC level would've been set to level 1, force it back to level 2
+  // PIC instead. This matches the behavior of Darwin GCC (based on
+  // chandlerc's informal testing in 2012).
+  if (PIC && ToolChain.getTriple().isOSDarwin())
+    IsPICLevelTwo |= ToolChain.isPICDefault();
+
+  // Note that these flags are trump-cards. Regardless of the order w.r.t. the
+  // PIC or PIE options above, if these show up, PIC is disabled.
+  if (KernelOrKext && (!Triple.isiOS() || Triple.isOSVersionLT(6)))
+    PIC = PIE = false;
+  if (Args.hasArg(options::OPT_static))
+    PIC = PIE = false;
+
+  if (Arg *A = Args.getLastArg(options::OPT_mdynamic_no_pic)) {
+    // This is a very special mode. It trumps the other modes, almost no one
+    // uses it, and it isn't even valid on any OS but Darwin.
+    if (!ToolChain.getTriple().isOSDarwin())
+      ToolChain.getDriver().Diag(diag::err_drv_unsupported_opt_for_target)
+          << A->getSpelling() << ToolChain.getTriple().str();
+
+    // FIXME: Warn when this flag trumps some other PIC or PIE flag.
+
+    // Only a forced PIC mode can cause the actual compile to have PIC defines
+    // etc., no flags are sufficient. This behavior was selected to closely
+    // match that of llvm-gcc and Apple GCC before that.
+    PIC = ToolChain.isPICDefault() && ToolChain.isPICDefaultForced();
+
+    return std::make_tuple(llvm::Reloc::DynamicNoPIC, PIC ? 2 : 0, false);
+  }
+
+  if (PIC)
+    return std::make_tuple(llvm::Reloc::PIC_, IsPICLevelTwo ? 2 : 1, PIE);
+
+  return std::make_tuple(llvm::Reloc::Static, 0, false);
+}
+
+static const char *RelocationModelName(llvm::Reloc::Model Model) {
+  switch (Model) {
+  case llvm::Reloc::Default:
+    return nullptr;
+  case llvm::Reloc::Static:
+    return "static";
+  case llvm::Reloc::PIC_:
+    return "pic";
+  case llvm::Reloc::DynamicNoPIC:
+    return "dynamic-no-pic";
+  }
+  assert(false && "Unknown Reloc::Model kind");
+}
+
+static void AddAssemblerKPIC(const ToolChain &ToolChain, const ArgList &Args,
+                             ArgStringList &CmdArgs) {
+  llvm::Reloc::Model RelocationModel;
+  unsigned PICLevel;
+  bool IsPIE;
+  std::tie(RelocationModel, PICLevel, IsPIE) =
+      ParsePICArgs(ToolChain, ToolChain.getTriple(), Args);
+
+  if (RelocationModel != llvm::Reloc::Static)
+    CmdArgs.push_back("-KPIC");
+}
+
 void Clang::ConstructJob(Compilation &C, const JobAction &JA,
                          const InputInfo &Output, const InputInfoList &Inputs,
                          const ArgList &Args, const char *LinkingOutput) const {
   std::string TripleStr = getToolChain().ComputeEffectiveClangTriple(Args);
   const llvm::Triple Triple(TripleStr);
 
   bool KernelOrKext =
       Args.hasArg(options::OPT_mkernel, options::OPT_fapple_kext);
   const Driver &D = getToolChain().getDriver();
   ArgStringList CmdArgs;
 
   bool IsWindowsGNU = getToolChain().getTriple().isWindowsGNUEnvironment();
if (isa<AnalyzeJobAction>(JA)) {
     CmdArgs.push_back("-w");
 
     // Add -Xanalyzer arguments when running as analyzer.
     Args.AddAllArgValues(CmdArgs, options::OPT_Xanalyzer);
   }
 
   CheckCodeGenerationOptions(D, Args);
 
-  bool PIE = getToolChain().isPIEDefault();
-  bool PIC = PIE || getToolChain().isPICDefault();
-  bool IsPICLevelTwo = PIC;
-
-  // Android-specific defaults for PIC/PIE
-  if (getToolChain().getTriple().getEnvironment() == llvm::Triple::Android) {
-    switch (getToolChain().getArch()) {
-    case llvm::Triple::arm:
-    case llvm::Triple::armeb:
-    case llvm::Triple::thumb:
-    case llvm::Triple::thumbeb:
-    case llvm::Triple::aarch64:
-    case llvm::Triple::mips:
-    case llvm::Triple::mipsel:
-    case llvm::Triple::mips64:
-    case llvm::Triple::mips64el:
-      PIC = true; // "-fpic"
-      break;
-
-    case llvm::Triple::x86:
-    case llvm::Triple::x86_64:
-      PIC = true; // "-fPIC"
-      IsPICLevelTwo = true;
-      break;
-
-    default:
-      break;
-    }
-  }
-
-  // OpenBSD-specific defaults for PIE
-  if (getToolChain().getTriple().getOS() == llvm::Triple::OpenBSD) {
-    switch (getToolChain().getArch()) {
-    case llvm::Triple::mips64:
-    case llvm::Triple::mips64el:
-    case llvm::Triple::sparcel:
-    case llvm::Triple::x86:
-    case llvm::Triple::x86_64:
-      IsPICLevelTwo = false; // "-fpie"
-      break;
-
-    case llvm::Triple::ppc:
-    case llvm::Triple::sparc:
-    case llvm::Triple::sparcv9:
-      IsPICLevelTwo = true; // "-fPIE"
-      break;
-
-    default:
-      break;
-    }
-  }
-
-  // For the PIC and PIE flag options, this logic is different from the
-  // legacy logic in very old versions of GCC, as that logic was just
-  // a bug no one had ever fixed. This logic is both more rational and
-  // consistent with GCC's new logic now that the bugs are fixed. The last
-  // argument relating to either PIC or PIE wins, and no other argument is
-  // used. If the last argument is any flavor of the '-fno-...' arguments,
-  // both PIC and PIE are disabled. Any PIE option implicitly enables PIC
-  // at the same level.
-  Arg *LastPICArg = Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,
-                                    options::OPT_fpic, options::OPT_fno_pic,
-                                    options::OPT_fPIE, options::OPT_fno_PIE,
-                                    options::OPT_fpie, options::OPT_fno_pie);
-  // Check whether the tool chain trumps the PIC-ness decision. If the PIC-ness
-  // is forced, then neither PIC nor PIE flags will have no effect.
-  if (!getToolChain().isPICDefaultForced()) {
-    if (LastPICArg) {
-      Option O = LastPICArg->getOption();
-      if (O.matches(options::OPT_fPIC) || O.matches(options::OPT_fpic) ||
-          O.matches(options::OPT_fPIE) || O.matches(options::OPT_fpie)) {
-        PIE = O.matches(options::OPT_fPIE) || O.matches(options::OPT_fpie);
-        PIC =
-            PIE || O.matches(options::OPT_fPIC) || O.matches(options::OPT_fpic);
-        IsPICLevelTwo =
-            O.matches(options::OPT_fPIE) || O.matches(options::OPT_fPIC);
-      } else {
-        PIE = PIC = false;
-      }
-    }
-  }
-
-  // Introduce a Darwin-specific hack. If the default is PIC but the flags
-  // specified while enabling PIC enabled level 1 PIC, just force it back to
-  // level 2 PIC instead. This matches the behavior of Darwin GCC (based on my
-  // informal testing).
-  if (PIC && getToolChain().getTriple().isOSDarwin())
-    IsPICLevelTwo |= getToolChain().isPICDefault();
-
-  // Note that these flags are trump-cards. Regardless of the order w.r.t. the
-  // PIC or PIE options above, if these show up, PIC is disabled.
-  if (KernelOrKext && (!Triple.isiOS() || Triple.isOSVersionLT(6)))
-    PIC = PIE = false;
-  if (Args.hasArg(options::OPT_static))
-    PIC = PIE = false;
-
-  if (Arg *A = Args.getLastArg(options::OPT_mdynamic_no_pic)) {
-    // This is a very special mode. It trumps the other modes, almost no one
-    // uses it, and it isn't even valid on any OS but Darwin.
-    if (!getToolChain().getTriple().isOSDarwin())
-      D.Diag(diag::err_drv_unsupported_opt_for_target)
-          << A->getSpelling() << getToolChain().getTriple().str();
-
-    // FIXME: Warn when this flag trumps some other PIC or PIE flag.
+  llvm::Reloc::Model RelocationModel;
+  unsigned PICLevel;
+  bool IsPIE;
+  std::tie(RelocationModel, PICLevel, IsPIE) =
+      ParsePICArgs(getToolChain(), Triple, Args);
 
+  const char *RMName = RelocationModelName(RelocationModel);
+  if (RMName) {
     CmdArgs.push_back("-mrelocation-model");
-    CmdArgs.push_back("dynamic-no-pic");
-
-    // Only a forced PIC mode can cause the actual compile to have PIC defines
-    // etc., no flags are sufficient. This behavior was selected to closely
-    // match that of llvm-gcc and Apple GCC before that.
-    if (getToolChain().isPICDefault() && getToolChain().isPICDefaultForced()) {
-      CmdArgs.push_back("-pic-level");
-      CmdArgs.push_back("2");
-    }
-  } else {
-    // Currently, LLVM only knows about PIC vs. static; the PIE differences are
-    // handled in Clang's IRGen by the -pie-level flag.
-    CmdArgs.push_back("-mrelocation-model");
-    CmdArgs.push_back(PIC ? "pic" : "static");
-
-    if (PIC) {
-      CmdArgs.push_back("-pic-level");
-      CmdArgs.push_back(IsPICLevelTwo ? "2" : "1");
-      if (PIE) {
-        CmdArgs.push_back("-pie-level");
-        CmdArgs.push_back(IsPICLevelTwo ? "2" : "1");
-      }
+    CmdArgs.push_back(RMName);
+  if (PICLevel > 0) {
+    CmdArgs.push_back(PICLevel == 1 ? "1" : "2");
+    if (IsPIE) {
+      CmdArgs.push_back(PICLevel == 1 ? "1" : "2");
     }
   }
 
   CmdArgs.push_back("-mthread-model");
   if (Arg *A = Args.getLastArg(options::OPT_mthread_model))
     CmdArgs.push_back(A->getValue());
   else
     CmdArgs.push_back(Args.MakeArgString(getToolChain().getThreadModel()));
if (SourceAction->getType() == types::TY_Asm ||
     // assembler on assembly source files.
     CmdArgs.push_back("-dwarf-debug-producer");
     CmdArgs.push_back(Args.MakeArgString(getClangFullVersion()));
 
     // And pass along -I options
     Args.AddAllArgs(CmdArgs, options::OPT_I);
   }
 
+  // Handle -fPIC et al -- the relocation-model affects the assembler
+  // for some targets.
+  llvm::Reloc::Model RelocationModel;
+  unsigned PICLevel;
+  bool IsPIE;
+  std::tie(RelocationModel, PICLevel, IsPIE) =
+      ParsePICArgs(getToolChain(), Triple, Args);
+
+  const char *RMName = RelocationModelName(RelocationModel);
+  if (RMName) {
+    CmdArgs.push_back("-mrelocation-model");
+    CmdArgs.push_back(RMName);
+  }
+
   // Optionally embed the -cc1as level arguments into the debug info, for build
   // analysis.
   if (getToolChain().UseDwarfDebugFlags()) {
     ArgStringList OriginalArgs;
     for (const auto &Arg : Args)
       Arg->render(Args, OriginalArgs);
 
     SmallString<256> Flags;
case llvm::Triple::mips64el: {
     break;
   }
 
   default:
     break;
   }
 
   if (NeedsKPIC)
-    addAssemblerKPIC(Args, CmdArgs);
+    AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
 
   Args.AddAllArgValues(CmdArgs, options::OPT_Wa_COMMA, options::OPT_Xassembler);
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
else if (getToolChain().getArch() == llvm::Triple::mips ||
     CmdArgs.push_back(getGnuCompatibleMipsABIName(ABIName).data());
 
     if (getToolChain().getArch() == llvm::Triple::mips ||
         getToolChain().getArch() == llvm::Triple::mips64)
       CmdArgs.push_back("-EB");
     else
       CmdArgs.push_back("-EL");
 
-    addAssemblerKPIC(Args, CmdArgs);
+    AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
   } else if (getToolChain().getArch() == llvm::Triple::arm ||
              getToolChain().getArch() == llvm::Triple::armeb ||
              getToolChain().getArch() == llvm::Triple::thumb ||
              getToolChain().getArch() == llvm::Triple::thumbeb) {
     const Driver &D = getToolChain().getDriver();
     const llvm::Triple &Triple = getToolChain().getTriple();
     StringRef FloatABI = arm::getARMFloatABI(D, Args, Triple);
 
void freebsd::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
   } else if (getToolChain().getArch() == llvm::Triple::sparc ||
              getToolChain().getArch() == llvm::Triple::sparcel ||
              getToolChain().getArch() == llvm::Triple::sparcv9) {
     if (getToolChain().getArch() == llvm::Triple::sparc)
       CmdArgs.push_back("-Av8plusa");
     else
       CmdArgs.push_back("-Av9a");
 
-    addAssemblerKPIC(Args, CmdArgs);
+    AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
   }
 
   Args.AddAllArgValues(CmdArgs, options::OPT_Wa_COMMA, options::OPT_Xassembler);
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
case llvm::Triple::mips64el: {
     CmdArgs.push_back(getGnuCompatibleMipsABIName(ABIName).data());
 
     if (getToolChain().getArch() == llvm::Triple::mips ||
         getToolChain().getArch() == llvm::Triple::mips64)
       CmdArgs.push_back("-EB");
     else
       CmdArgs.push_back("-EL");
 
-    addAssemblerKPIC(Args, CmdArgs);
+    AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
     break;
   }
 
   case llvm::Triple::sparc:
   case llvm::Triple::sparcel:
     CmdArgs.push_back("-32");
-    addAssemblerKPIC(Args, CmdArgs);
+    AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
     break;
 
   case llvm::Triple::sparcv9:
     CmdArgs.push_back("-64");
     CmdArgs.push_back("-Av9");
-    addAssemblerKPIC(Args, CmdArgs);
+    AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
     break;
 
   default:
     break;
   }
 
   Args.AddAllArgValues(CmdArgs, options::OPT_Wa_COMMA, options::OPT_Xassembler);
 
void gnutools::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
   claimNoWarnArgs(Args);
 
   std::string TripleStr = getToolChain().ComputeEffectiveClangTriple(Args);
   llvm::Triple Triple = llvm::Triple(TripleStr);
 
   ArgStringList CmdArgs;
   bool NeedsKPIC = false;
 
+  llvm::Reloc::Model RelocationModel;
+  unsigned PICLevel;
+  bool IsPIE;
+  std::tie(RelocationModel, PICLevel, IsPIE) =
+      ParsePICArgs(getToolChain(), Triple, Args);
+
   switch (getToolChain().getArch()) {
   default:
     break;
   // Add --32/--64 to make sure we get the format we want.
   // This is incomplete
   case llvm::Triple::x86:
     CmdArgs.push_back("--32");
     break;
case llvm::Triple::mips64el: {
     CmdArgs.push_back("-march");
     CmdArgs.push_back(CPUName.data());
 
     CmdArgs.push_back("-mabi");
     CmdArgs.push_back(ABIName.data());
 
     // -mno-shared should be emitted unless -fpic, -fpie, -fPIC, -fPIE,
     // or -mshared (not implemented) is in effect.
-    bool IsPicOrPie = false;
-    if (Arg *A = Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,
-                                 options::OPT_fpic, options::OPT_fno_pic,
-                                 options::OPT_fPIE, options::OPT_fno_PIE,
-                                 options::OPT_fpie, options::OPT_fno_pie)) {
-      if (A->getOption().matches(options::OPT_fPIC) ||
-          A->getOption().matches(options::OPT_fpic) ||
-          A->getOption().matches(options::OPT_fPIE) ||
-          A->getOption().matches(options::OPT_fpie))
-        IsPicOrPie = true;
-    }
-    if (!IsPicOrPie)
+    if (RelocationModel == llvm::Reloc::Static)
       CmdArgs.push_back("-mno-shared");
 
     // LLVM doesn't support -mplt yet and acts as if it is always given.
     // However, -mplt has no effect with the N64 ABI.
     CmdArgs.push_back(ABIName == "64" ? "-KPIC" : "-call_nonpic");
 
     if (getToolChain().getArch() == llvm::Triple::mips ||
         getToolChain().getArch() == llvm::Triple::mips64)
case llvm::Triple::systemz: {
     // Always pass an -march option, since our default of z10 is later
     // than the GNU assembler's default.
     StringRef CPUName = getSystemZTargetCPU(Args);
     CmdArgs.push_back(Args.MakeArgString("-march=" + CPUName));
     break;
   }
   }
 
-  if (NeedsKPIC)
-    addAssemblerKPIC(Args, CmdArgs);
+  if (NeedsKPIC) {
+    if (RelocationModel != llvm::Reloc::Static)
+      CmdArgs.push_back("-KPIC");
+  }
 
   Args.AddAllArgs(CmdArgs, options::OPT_I);
   Args.AddAllArgValues(CmdArgs, options::OPT_Wa_COMMA, options::OPT_Xassembler);
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)

test/Driver/integrated-as.s

 // RUN: %clang -### -c -integrated-as %s 2>&1 | FileCheck %s
 // CHECK: cc1as
 // CHECK-NOT: -relax-all
 
 // RUN: %clang -### -c -integrated-as -Wa,-L %s 2>&1 | FileCheck --check-prefix=OPT_L %s
 // OPT_L: msave-temp-labels
 
-// RUN: %clang -### -target x86_64-linux-gnu -c -integrated-as %s -fsanitize=address 2>&1 %s | FileCheck --check-prefix=SANITIZE %s
-// SANITIZE: argument unused during compilation: '-fsanitize=address'
-
 // Test that -I params in -Wa, and -Xassembler args are passed to integrated assembler
 // RUN: %clang -### -c -integrated-as %s -Wa,-I,foo_dir 2>&1 | FileCheck --check-prefix=WA_INCLUDE1 %s
 // WA_INCLUDE1: cc1as
 // WA_INCLUDE1: "-I" "foo_dir"
 
 // RUN: %clang -### -c -integrated-as %s -Wa,-Ifoo_dir 2>&1 | FileCheck --check-prefix=WA_INCLUDE2 %s
 // WA_INCLUDE2: cc1as
 // WA_INCLUDE2: "-Ifoo_dir"

 // RUN: %clang -### -c -integrated-as %s -Xassembler -gdwarf-2 2>&1 | FileCheck --check-prefix=DWARF2XASSEMBLER %s
 // DWARF2XASSEMBLER: "-gdwarf-2"
 
 // RUN: %clang -### -c -integrated-as %s -Wa,-gdwarf-2 2>&1 | FileCheck --check-prefix=DWARF2WA %s
 // DWARF2WA: "-gdwarf-2"
 
 // RUN: %clang -### -x assembler -c -integrated-as %s -I myincludedir 2>&1 | FileCheck --check-prefix=INCLUDEPATH %s
 // INCLUDEPATH: "-I" "myincludedir"
+
+// RUN: %clang -### -x assembler -c -fPIC -integrated-as %s 2>&1 | FileCheck --check-prefix=PIC %s
+// PIC: "-mrelocation-model" "pic"