[mips] Correct the invocation of GAS in several cases.

Summary:
As a result of this patch, assembling an empty file with GCC and Clang (using
GAS as the assembler) now produces identical objects.

-mfp32/-mfpxx/-mfp64 now form a trinity of options. -mfpxx is the default
when the triple vendor is 'img' or 'mti', the ABI is O32, and the CPU is
between mips2 and mips32r2/mips64r2 (inclusive).

-mno-shared is always given to the assembler to match the effect of
-mabicalls (currently unimplemented but Clang acts as if it is given).
Similarly, -call_nonpic is always given to match the effect of -mplt (also
unimplemented and acts as if given) except when the ABI is 64 in which case
-mplt has no effect so -KPIC is given instead.

-mhard-float/-msoft-float are now passed on.

-modd-spreg/-mno-odd-spreg are now passed on.

-mno-mips16 is correctly passed on. The assembler option is -no-mips16 not
-mno-mips16

Differential Revision: http://reviews.llvm.org/D4515

llvm-svn: 213138

1 files changed, 2 insertions, 0 deletions

diff --git a/clang/lib/Driver/Tools.h b/clang/lib/Driver/Tools.h
index bc7f58bfbe9..476c1872c80 100644
--- a/clang/lib/Driver/Tools.h
+++ b/clang/lib/Driver/Tools.h
@@ -219,6 +219,8 @@ namespace arm {
 namespace mips {
   bool hasMipsAbiArg(const llvm::opt::ArgList &Args, const char *Value);
   bool isNaN2008(const llvm::opt::ArgList &Args, const llvm::Triple &Triple);
+  bool isFPXXDefault(const llvm::Triple &Triple, StringRef CPUName,
+                     StringRef ABIName);
 }
 
 namespace darwin {