[mips] Correct linux dynamic linker for -mnan=2008

[dsanders]

Summary

The dynamic linker is named ld-linux-mipsn8.so.1 when -mnan=2008 is given (or
is the default). It remains ld.so.1 for other cases.

This is necessary for MIPS32r6/MIPS64r6 since these ISA's default to -mnan=2008.

[atanasyan]

LGTM with a small note.

lib/Driver/Tools.cpp

5105

As to me I would write this code as follow to escape redundant checking of the -mcpu arguments if -mnan option is provided:

if (Arg *NaNArg = Args.getLastArg(options::OPT_mnan_EQ))
  return llvm::StringSwitch<bool>(NaNArg->getValue())
                .Case("2008", true)
                .Case("legacy", false)
                .Default(false);

// NaN2008 is the default for MIPS32r6/MIPS64r6.
if (Arg *CPUArg = Args.getLastArg(options::OPT_mcpu_EQ))
  return llvm::StringSwitch<bool>(CPUArg->getValue())
                .Cases("mips32r6", "mips64r6", true)
                .Default(false);

return false;

[dsanders]

lib/Driver/Tools.cpp

5105

Good point. I'll change to that before commit

[dsanders]

Make the change suggested by Simon and fix a couple silly mistakes caught by
'ninja check-clang'.

lib/Driver/Tools.h

StringRef getARMTargetCPU(const llvm::opt::ArgList &Args,
                             const llvm::Triple &Triple);
   const char* getARMCPUForMArch(const llvm::opt::ArgList &Args,
                                 const llvm::Triple &Triple);
   const char* getLLVMArchSuffixForARM(StringRef CPU);
 }
 
 namespace mips {
   bool hasMipsAbiArg(const llvm::opt::ArgList &Args, const char *Value);
+  bool isNaN2008(const llvm::opt::ArgList &Args);
 }
 
 namespace darwin {
   llvm::Triple::ArchType getArchTypeForMachOArchName(StringRef Str);
   void setTripleTypeForMachOArchName(llvm::Triple &T, StringRef Str);
 
   class LLVM_LIBRARY_VISIBILITY MachOTool : public Tool {
     virtual void anchor();

lib/Driver/Tools.cpp

return llvm::StringSwitch<const char *>(CPU)
     .Default("");
 }
 
 bool mips::hasMipsAbiArg(const ArgList &Args, const char *Value) {
   Arg *A = Args.getLastArg(options::OPT_mabi_EQ);
   return A && (A->getValue() == StringRef(Value));
 }
 
+bool mips::isNaN2008(const ArgList &Args) {
+  if (Arg *NaNArg = Args.getLastArg(options::OPT_mnan_EQ))
+    return llvm::StringSwitch<bool>(NaNArg->getValue())
+               .Case("2008", true)
+               .Case("legacy", false)
+               .Default(false);
+
+  // NaN2008 is the default for MIPS32r6/MIPS64r6.
+  if (Arg *CPUArg = Args.getLastArg(options::OPT_mcpu_EQ))
+    return llvm::StringSwitch<bool>(CPUArg->getValue())
+               .Cases("mips32r6", "mips64r6", true)
+               .Default(false);
+
+  return false;
+}
+
 llvm::Triple::ArchType darwin::getArchTypeForMachOArchName(StringRef Str) {
   // See arch(3) and llvm-gcc's driver-driver.c. We don't implement support for
   // archs which Darwin doesn't use.
 
   // The matching this routine does is fairly pointless, since it is neither the
   // complete architecture list, nor a reasonable subset. The problem is that
   // historically the driver driver accepts this and also ties its -march=
   // handling to the architecture name, so we need to be careful before removing
else
       return "/lib/ld-linux.so.3";
   } else if (ToolChain.getArch() == llvm::Triple::armeb ||
              ToolChain.getArch() == llvm::Triple::thumbeb) {
     if (ToolChain.getTriple().getEnvironment() == llvm::Triple::GNUEABIHF)
       return "/lib/ld-linux-armhf.so.3";        /* TODO: check which dynamic linker name.  */
     else
       return "/lib/ld-linux.so.3";              /* TODO: check which dynamic linker name.  */
   } else if (ToolChain.getArch() == llvm::Triple::mips ||
-             ToolChain.getArch() == llvm::Triple::mipsel)
+             ToolChain.getArch() == llvm::Triple::mipsel) {
+    if (mips::isNaN2008(Args))
+      return "/lib/ld-linux-mipsn8.so.1";
     return "/lib/ld.so.1";
-  else if (ToolChain.getArch() == llvm::Triple::mips64 ||
+  } else if (ToolChain.getArch() == llvm::Triple::mips64 ||
            ToolChain.getArch() == llvm::Triple::mips64el) {
+    std::string LinkerFile = mips::isNaN2008(Args) ? "ld-linux-mipsn8.so.1"
+                                                   : "ld.so.1";
     if (mips::hasMipsAbiArg(Args, "n32"))
-      return "/lib32/ld.so.1";
-    else
-      return "/lib64/ld.so.1";
+      return "/lib32/" + LinkerFile;
+    return "/lib64/" + LinkerFile;
   } else if (ToolChain.getArch() == llvm::Triple::ppc)
     return "/lib/ld.so.1";
   else if (ToolChain.getArch() == llvm::Triple::ppc64 ||
            ToolChain.getArch() == llvm::Triple::systemz)
     return "/lib64/ld64.so.1";
   else if (ToolChain.getArch() == llvm::Triple::ppc64le)
     return "/lib64/ld64.so.2";
   else if (ToolChain.getArch() == llvm::Triple::sparcv9)

test/Driver/linux-ld.c

 // for MIPS platforms.
 // RUN: %clang %s -### -o %t.o 2>&1 \
 // RUN:     --target=mips-linux-gnu \
 // RUN:   | FileCheck --check-prefix=CHECK-MIPS %s
 // CHECK-MIPS: "{{.*}}ld{{(.exe)?}}"
 // CHECK-MIPS: "-m" "elf32btsmip"
 // CHECK-MIPS: "-dynamic-linker" "{{.*}}/lib/ld.so.1"
 // CHECK-MIPS-NOT: "--hash-style={{gnu|both}}"
+//
 // RUN: %clang %s -### -o %t.o 2>&1 \
 // RUN:     --target=mipsel-linux-gnu \
 // RUN:   | FileCheck --check-prefix=CHECK-MIPSEL %s
 // CHECK-MIPSEL: "{{.*}}ld{{(.exe)?}}"
 // CHECK-MIPSEL: "-m" "elf32ltsmip"
 // CHECK-MIPSEL: "-dynamic-linker" "{{.*}}/lib/ld.so.1"
 // CHECK-MIPSEL-NOT: "--hash-style={{gnu|both}}"
+//
+// RUN: %clang %s -### -o %t.o 2>&1 --target=mipsel-linux-gnu -mnan=2008 \
+// RUN:   | FileCheck --check-prefix=CHECK-MIPSEL-NAN2008 %s
+// CHECK-MIPSEL-NAN2008: "{{.*}}ld{{(.exe)?}}"
+// CHECK-MIPSEL-NAN2008: "-m" "elf32ltsmip"
+// CHECK-MIPSEL-NAN2008: "-dynamic-linker" "{{.*}}/lib/ld-linux-mipsn8.so.1"
+// CHECK-MIPSEL-NAN2008-NOT: "--hash-style={{gnu|both}}"
+//
+// RUN: %clang %s -### -o %t.o 2>&1 --target=mipsel-linux-gnu -mcpu=mips32r6 \
+// RUN:   | FileCheck --check-prefix=CHECK-MIPS32R6EL %s
+// CHECK-MIPS32R6EL: "{{.*}}ld{{(.exe)?}}"
+// CHECK-MIPS32R6EL: "-m" "elf32ltsmip"
+// CHECK-MIPS32R6EL: "-dynamic-linker" "{{.*}}/lib/ld-linux-mipsn8.so.1"
+// CHECK-MIPS32R6EL-NOT: "--hash-style={{gnu|both}}"
+//
 // RUN: %clang %s -### -o %t.o 2>&1 \
 // RUN:     --target=mips64-linux-gnu \
 // RUN:   | FileCheck --check-prefix=CHECK-MIPS64 %s
 // CHECK-MIPS64: "{{.*}}ld{{(.exe)?}}"
 // CHECK-MIPS64: "-m" "elf64btsmip"
 // CHECK-MIPS64: "-dynamic-linker" "{{.*}}/lib64/ld.so.1"
 // CHECK-MIPS64-NOT: "--hash-style={{gnu|both}}"
+//
 // RUN: %clang %s -### -o %t.o 2>&1 \
 // RUN:     --target=mips64el-linux-gnu \
 // RUN:   | FileCheck --check-prefix=CHECK-MIPS64EL %s
 // CHECK-MIPS64EL: "{{.*}}ld{{(.exe)?}}"
 // CHECK-MIPS64EL: "-m" "elf64ltsmip"
 // CHECK-MIPS64EL: "-dynamic-linker" "{{.*}}/lib64/ld.so.1"
 // CHECK-MIPS64EL-NOT: "--hash-style={{gnu|both}}"
+//
+// RUN: %clang %s -### -o %t.o 2>&1 --target=mips64el-linux-gnu -mnan=2008 \
+// RUN:   | FileCheck --check-prefix=CHECK-MIPS64EL-NAN2008 %s
+// CHECK-MIPS64EL-NAN2008: "{{.*}}ld{{(.exe)?}}"
+// CHECK-MIPS64EL-NAN2008: "-m" "elf64ltsmip"
+// CHECK-MIPS64EL-NAN2008: "-dynamic-linker" "{{.*}}/lib64/ld-linux-mipsn8.so.1"
+// CHECK-MIPS64EL-NAN2008-NOT: "--hash-style={{gnu|both}}"
+//
+// RUN: %clang %s -### -o %t.o 2>&1 --target=mips64el-linux-gnu -mcpu=mips64r6 \
+// RUN:   | FileCheck --check-prefix=CHECK-MIPS64R6EL %s
+// CHECK-MIPS64R6EL: "{{.*}}ld{{(.exe)?}}"
+// CHECK-MIPS64R6EL: "-m" "elf64ltsmip"
+// CHECK-MIPS64R6EL: "-dynamic-linker" "{{.*}}/lib64/ld-linux-mipsn8.so.1"
+// CHECK-MIPS64R6EL-NOT: "--hash-style={{gnu|both}}"
+//
 // RUN: %clang %s -### -o %t.o 2>&1 \
 // RUN:     --target=mips64-linux-gnu -mabi=n32 \
 // RUN:   | FileCheck --check-prefix=CHECK-MIPS64-N32 %s
 // CHECK-MIPS64-N32: "{{.*}}ld{{(.exe)?}}"
 // CHECK-MIPS64-N32: "-m" "elf32btsmipn32"
 // CHECK-MIPS64-N32: "-dynamic-linker" "{{.*}}/lib32/ld.so.1"
 // CHECK-MIPS64-N32-NOT: "--hash-style={{gnu|both}}"
+//
 // RUN: %clang %s -### -o %t.o 2>&1 \
 // RUN:     --target=mips64el-linux-gnu -mabi=n32 \
 // RUN:   | FileCheck --check-prefix=CHECK-MIPS64EL-N32 %s
 // CHECK-MIPS64EL-N32: "{{.*}}ld{{(.exe)?}}"
 // CHECK-MIPS64EL-N32: "-m" "elf32ltsmipn32"
 // CHECK-MIPS64EL-N32: "-dynamic-linker" "{{.*}}/lib32/ld.so.1"
 // CHECK-MIPS64EL-N32-NOT: "--hash-style={{gnu|both}}"
 //
+// RUN: %clang %s -### -o %t.o 2>&1 --target=mips64el-linux-gnu -mabi=n32 \
+// RUN:   -mnan=2008 | FileCheck --check-prefix=CHECK-MIPS64EL-N32-NAN2008 %s
+// CHECK-MIPS64EL-N32-NAN2008: "{{.*}}ld{{(.exe)?}}"
+// CHECK-MIPS64EL-N32-NAN2008: "-m" "elf32ltsmipn32"
+// CHECK-MIPS64EL-N32-NAN2008: "-dynamic-linker" "{{.*}}/lib32/ld-linux-mipsn8.so.1"
+// CHECK-MIPS64EL-N32-NAN2008-NOT: "--hash-style={{gnu|both}}"
+//
 // RUN: %clang %s -### -o %t.o 2>&1 \
 // RUN:     --target=sparc-linux-gnu \
 // RUN:   | FileCheck --check-prefix=CHECK-SPARCV8 %s
 // CHECK-SPARCV8: "{{.*}}ld{{(.exe)?}}"
 // CHECK-SPARCV8: "-m" "elf32_sparc"
 // CHECK-SPARCV8: "-dynamic-linker" "/lib/ld-linux.so.2"
 //
 // RUN: %clang %s -### -o %t.o 2>&1 \