From 97f52ac45369f6925b548404e61d511034c874ec Mon Sep 17 00:00:00 2001
From: Daniel Dunbar <daniel@zuster.org>
Date: Sat, 19 Dec 2009 04:15:38 +0000
Subject: [PATCH] ARM: Use front-end specific target features "soft-float" and
 "soft-float-abi" to communicate FP mode to target; __SOFTFP__ is set
 correctly now.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@91755 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Basic/Targets.cpp | 40 ++++++++++++++++++++++++++++++++++++----
 lib/Driver/Tools.cpp  | 20 +++++++++++++++++++-
 2 files changed, 55 insertions(+), 5 deletions(-)

diff --git a/lib/Basic/Targets.cpp b/lib/Basic/Targets.cpp
index 7cc9f73b6c..66d1814bdb 100644
--- a/lib/Basic/Targets.cpp
+++ b/lib/Basic/Targets.cpp
@@ -1187,7 +1187,11 @@ class ARMTargetInfo : public TargetInfo {
    static const char * const GCCRegNames[];
 
   std::string ABI, CPU;
-  bool IsThumb;
+  unsigned IsThumb : 1;
+
+  // Initialized via features.
+  unsigned SoftFloat : 1;
+  unsigned SoftFloatABI : 1;
 
 public:
   ARMTargetInfo(const std::string &TripleStr)
@@ -1240,6 +1244,36 @@ public:
 
     return true;
   }
+
+  virtual bool setFeatureEnabled(llvm::StringMap<bool> &Features,
+                                 const std::string &Name,
+                                 bool Enabled) const {
+    if (Name != "soft-float" && Name != "soft-float-abi")
+      return false;
+
+    Features[Name] = Enabled;
+    return true;
+  }
+
+  virtual void HandleTargetFeatures(std::vector<std::string> &Features) {
+    SoftFloat = SoftFloatABI = false;
+    for (unsigned i = 0, e = Features.size(); i != e; ++i) {
+      if (Features[i] == "+soft-float")
+        SoftFloat = true;
+      else if (Features[i] == "+soft-float-abi")
+        SoftFloatABI = true;
+    }
+
+    // Remove front-end specific options which the backend handles differently.
+    std::vector<std::string>::iterator it;
+    it = std::find(Features.begin(), Features.end(), "+soft-float");
+    if (it != Features.end())
+      Features.erase(it);
+    it = std::find(Features.begin(), Features.end(), "+soft-float-abi");
+    if (it != Features.end())
+      Features.erase(it);
+  }
+
   static const char *getCPUDefineSuffix(llvm::StringRef Name) {
     return llvm::StringSwitch<const char*>(Name)
       .Cases("arm8", "arm810", "4")
@@ -1294,9 +1328,7 @@ public:
     if (ABI == "aapcs" || ABI == "aapcs-linux")
       Define(Defs, "__ARM_EABI__");
 
-    // FIXME: This isn't correct, this should be set based on the various float
-    // options.
-    if (CPUArch[0] <= '5')
+    if (SoftFloat)
       Define(Defs, "__SOFTFP__");
 
     if (CPU == "xscale")
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index b1846b34c2..3dcdbbceca 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -230,7 +230,7 @@ static const char *getARMTargetCPU(const ArgList &Args) {
     if (MArch == "armv5e" || MArch == "armv5te")
       return "arm1026ejs";
     if (MArch == "armv5tej")
-      return "arm926ejs";
+      return "arm926ej-s";
     if (MArch == "armv6" || MArch == "armv6k")
       return "arm1136jf-s";
     if (MArch == "armv6j")
@@ -432,6 +432,24 @@ void Clang::AddARMTargetArgs(const ArgList &Args,
     CmdArgs.push_back("-mfloat-abi");
     CmdArgs.push_back("hard");
   }
+
+  // Set appropriate target features for floating point mode.
+  //
+  // FIXME: Note, this is a hack, the LLVM backend doesn't actually use these
+  // yet (it uses the -mfloat-abi and -msoft-float options above), and it is
+  // stripped out by the ARM target.
+
+  // Use software floating point operations?
+  if (FloatABI == "soft") {
+    CmdArgs.push_back("-target-feature");
+    CmdArgs.push_back("+soft-float");
+  }
+
+  // Use software floating point argument passing?
+  if (FloatABI != "hard") {
+    CmdArgs.push_back("-target-feature");
+    CmdArgs.push_back("+soft-float-abi");
+  }
 }
 
 void Clang::AddX86TargetArgs(const ArgList &Args,
-- 
2.40.0