[mips] Set default float ABI to "soft" on FreeBSD

Initial patch by Kyle Evans.

Fix PR43596

llvm-svn: 374154

clang/lib/Driver/ToolChains/Arch/Mips.cpp

@@ -149,7 +149,8 @@ StringRef mips::getGnuCompatibleMipsABIName(StringRef ABI) {
 
 // Select the MIPS float ABI as determined by -msoft-float, -mhard-float,
 // and -mfloat-abi=.
-mips::FloatABI mips::getMipsFloatABI(const Driver &D, const ArgList &Args) {
+mips::FloatABI mips::getMipsFloatABI(const Driver &D, const ArgList &Args,
+                                     const llvm::Triple &Triple) {
   mips::FloatABI ABI = mips::FloatABI::Invalid;
   if (Arg *A =
           Args.getLastArg(options::OPT_msoft_float, options::OPT_mhard_float,
@@ -172,10 +173,15 @@ mips::FloatABI mips::getMipsFloatABI(const Driver &D, const ArgList &Args) {
 
   // If unspecified, choose the default based on the platform.
   if (ABI == mips::FloatABI::Invalid) {
-    // Assume "hard", because it's a default value used by gcc.
-    // When we start to recognize specific target MIPS processors,
-    // we will be able to select the default more correctly.
-    ABI = mips::FloatABI::Hard;
+    if (Triple.isOSFreeBSD()) {
+      // For FreeBSD, assume "soft" on all flavors of MIPS.
+      ABI = mips::FloatABI::Soft;
+    } else {
+      // Assume "hard", because it's a default value used by gcc.
+      // When we start to recognize specific target MIPS processors,
+      // we will be able to select the default more correctly.
+      ABI = mips::FloatABI::Hard;
+    }
   }
 
   assert(ABI != mips::FloatABI::Invalid && "must select an ABI");
@@ -274,7 +280,7 @@ void mips::getMIPSTargetFeatures(const Driver &D, const llvm::Triple &Triple,
       Features.push_back("-xgot");
   }
 
-  mips::FloatABI FloatABI = mips::getMipsFloatABI(D, Args);
+  mips::FloatABI FloatABI = mips::getMipsFloatABI(D, Args, Triple);
   if (FloatABI == mips::FloatABI::Soft) {
     // FIXME: Note, this is a hack. We need to pass the selected float
     // mode to the MipsTargetInfoBase to define appropriate macros there.

clang/lib/Driver/ToolChains/Arch/Mips.h

@@ -38,7 +38,8 @@ void getMIPSTargetFeatures(const Driver &D, const llvm::Triple &Triple,
                            const llvm::opt::ArgList &Args,
                            std::vector<StringRef> &Features);
 StringRef getGnuCompatibleMipsABIName(StringRef ABI);
-mips::FloatABI getMipsFloatABI(const Driver &D, const llvm::opt::ArgList &Args);
+mips::FloatABI getMipsFloatABI(const Driver &D, const llvm::opt::ArgList &Args,
+                               const llvm::Triple &Triple);
 std::string getMipsABILibSuffix(const llvm::opt::ArgList &Args,
                                 const llvm::Triple &Triple);
 bool hasMipsAbiArg(const llvm::opt::ArgList &Args, const char *Value);

clang/lib/Driver/ToolChains/Clang.cpp

@@ -1672,7 +1672,7 @@ void Clang::AddMIPSTargetArgs(const ArgList &Args,
   CmdArgs.push_back("-target-abi");
   CmdArgs.push_back(ABIName.data());
 
-  mips::FloatABI ABI = mips::getMipsFloatABI(D, Args);
+  mips::FloatABI ABI = mips::getMipsFloatABI(D, Args, Triple);
   if (ABI == mips::FloatABI::Soft) {
     // Floating point operations and argument passing are soft.
     CmdArgs.push_back("-msoft-float");

clang/lib/Driver/ToolChains/Gnu.cpp

@@ -823,7 +823,8 @@ void tools::gnutools::Assembler::ConstructJob(Compilation &C,
       A->render(Args, CmdArgs);
     } else if (mips::shouldUseFPXX(
                    Args, getToolChain().getTriple(), CPUName, ABIName,
-                   mips::getMipsFloatABI(getToolChain().getDriver(), Args)))
+                   mips::getMipsFloatABI(getToolChain().getDriver(), Args,
+                                         getToolChain().getTriple())))
       CmdArgs.push_back("-mfpxx");
 
     // Pass on -mmips16 or -mno-mips16. However, the assembler equivalent of

clang/test/Driver/mips-float.c

@@ -7,6 +7,14 @@
 // RUN:   | FileCheck --check-prefix=CHECK-DEF %s
 // CHECK-DEF: "-mfloat-abi" "hard"
 //
+// Default on FreeBSD
+// RUN: %clang -c %s -### -o %t.o 2>&1 \
+// RUN:     -target mips-freebsd12 \
+// RUN:   | FileCheck --check-prefix=DEF-FREEBSD %s
+// DEF-FREEBSD: "-target-feature" "+soft-float"
+// DEF-FREEBSD: "-msoft-float"
+// DEF-FREEBSD: "-mfloat-abi" "soft"
+//
 // -mhard-float
 // RUN: %clang -c %s -### -o %t.o 2>&1 \
 // RUN:     -target mips-linux-gnu -mhard-float \