Add support for MIPS' floating ABIs (hard, soft and single) to clang driver.

Patch by Simon Atanasyan.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@153348 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 35 insertions, 9 deletions

diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index bd65d6acc8..c0767c372f 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -787,31 +787,57 @@ void Clang::AddMIPSTargetArgs(const ArgList &Args,
   CmdArgs.push_back("-target-abi");
   CmdArgs.push_back(ABIName);
 
-  // Select the float ABI as determined by -msoft-float, -mhard-float, and
+  // Select the float ABI as determined by -msoft-float, -mhard-float,
+  // and -mfloat-abi=.
   StringRef FloatABI;
   if (Arg *A = Args.getLastArg(options::OPT_msoft_float,
-                               options::OPT_mhard_float)) {
+                               options::OPT_mhard_float,
+                               options::OPT_mfloat_abi_EQ)) {
     if (A->getOption().matches(options::OPT_msoft_float))
       FloatABI = "soft";
     else if (A->getOption().matches(options::OPT_mhard_float))
       FloatABI = "hard";
+    else {
+      FloatABI = A->getValue(Args);
+      if (FloatABI != "soft" && FloatABI != "single" && FloatABI != "hard") {
+        D.Diag(diag::err_drv_invalid_mfloat_abi)
+          << A->getAsString(Args);
+        FloatABI = "hard";
+      }
+    }
   }
 
   // If unspecified, choose the default based on the platform.
   if (FloatABI.empty()) {
-    // Assume "soft", but warn the user we are guessing.
-    FloatABI = "soft";
-    D.Diag(diag::warn_drv_assuming_mfloat_abi_is) << "soft";
+    // 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.
+    FloatABI = "hard";
   }
 
   if (FloatABI == "soft") {
     // Floating point operations and argument passing are soft.
-    //
-    // FIXME: This changes CPP defines, we need -target-soft-float.
     CmdArgs.push_back("-msoft-float");
-  } else {
+    CmdArgs.push_back("-mfloat-abi");
+    CmdArgs.push_back("soft");
+
+    // FIXME: Note, this is a hack. We need to pass the selected float
+    // mode to the MipsTargetInfoBase to define appropriate macros there.
+    // Now it is the only method.
+    CmdArgs.push_back("-target-feature");
+    CmdArgs.push_back("+soft-float");
+  }
+  else if (FloatABI == "single") {
+    // Restrict the use of hardware floating-point
+    // instructions to 32-bit operations.
+    CmdArgs.push_back("-target-feature");
+    CmdArgs.push_back("+single-float");
+  }
+  else {
+    // Floating point operations and argument passing are hard.
     assert(FloatABI == "hard" && "Invalid float abi!");
-    CmdArgs.push_back("-mhard-float");
+    CmdArgs.push_back("-mfloat-abi");
+    CmdArgs.push_back("hard");
   }
 }