Bring back r250262: PS4 toolchain

There was a minor problem with a test. Sorry for the noise yesterday.

This patch adds missing pieces to clang, including the PS4 toolchain
definition, added warnings, PS4 defaults, and Driver changes needed for
our compiler.

A patch by Filipe Cabecinhas, Pierre Gousseau and Katya Romanova!

Differential Revision: http://reviews.llvm.org/D13482

llvm-svn: 250293
diff --git a/clang/lib/Driver/ToolChains.h b/clang/lib/Driver/ToolChains.h
index 58b417c..17a3b64 100644
--- a/clang/lib/Driver/ToolChains.h
+++ b/clang/lib/Driver/ToolChains.h
@@ -1015,6 +1015,27 @@
                              llvm::opt::ArgStringList &CC1Args) const override;
 };
 
+class LLVM_LIBRARY_VISIBILITY PS4CPU : public Generic_ELF {
+public:
+  PS4CPU(const Driver &D, const llvm::Triple &Triple,
+         const llvm::opt::ArgList &Args);
+
+  bool IsMathErrnoDefault() const override { return false; }
+  bool IsObjCNonFragileABIDefault() const override { return true; }
+  bool HasNativeLLVMSupport() const override;
+  bool isPICDefault() const override;
+
+  unsigned GetDefaultStackProtectorLevel(bool KernelOrKext) const override {
+    return 2; // SSPStrong
+  }
+
+  SanitizerMask getSupportedSanitizers() const override;
+
+protected:
+  Tool *buildAssembler() const override;
+  Tool *buildLinker() const override;
+};
+
 } // end namespace toolchains
 } // end namespace driver
 } // end namespace clang