[driver] Allow the driver to directly accept the -no-implicit-float option, so that the

generation of implicit floating point instructions can be disable for ARM. 
rdar://11409142


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156942 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Driver/CC1Options.td

@@ -146,8 +146,6 @@ def dwarf_debug_flags : Separate<"-dwarf-debug-flags">,
   HelpText<"The string to embed in the Dwarf debug flags record.">;
 def fforbid_guard_variables : Flag<"-fforbid-guard-variables">,
   HelpText<"Emit an error if a C++ static local initializer would need a guard variable">;
-def no_implicit_float : Flag<"-no-implicit-float">,
-  HelpText<"Don't generate implicit floating point instructions (x86-only)">;
 def fdump_vtable_layouts : Flag<"-fdump-vtable-layouts">,
   HelpText<"Dump the layouts of all vtables that will be emitted in a translation unit">;
 def femit_coverage_notes : Flag<"-femit-coverage-notes">,

include/clang/Driver/Options.td

@@ -800,6 +800,8 @@ def mrtd : Flag<"-mrtd">, Group<m_Group>, Flags<[CC1Option]>,
 def msmall_data_threshold_EQ : Joined <"-msmall-data-threshold=">, Group<m_Group>;
 def msoft_float : Flag<"-msoft-float">, Group<m_Group>, Flags<[CC1Option]>,
   HelpText<"Use software floating point">;
+def no_implicit_float : Flag<"-no-implicit-float">, Flags<[CC1Option]>,
+  HelpText<"Don't generate implicit floating point instructions">;
 def msse2 : Flag<"-msse2">, Group<m_x86_Features_Group>;
 def msse3 : Flag<"-msse3">, Group<m_x86_Features_Group>;
 def msse4a : Flag<"-msse4a">, Group<m_x86_Features_Group>;

lib/Driver/Tools.cpp

@@ -755,6 +755,9 @@ void Clang::AddARMTargetArgs(const ArgList &Args,
     if (A->getOption().matches(options::OPT_mno_global_merge))
       CmdArgs.push_back("-mno-global-merge");
   }
+
+  if (Args.hasArg(options::OPT_no_implicit_float))
+    CmdArgs.push_back("-no-implicit-float");
 }
 
 // Get default architecture.

test/Driver/flags.c

@@ -7,3 +7,5 @@
 // RUN: %clang -target i386-apple-darwin9 -### -S -mno-soft-float %s -msoft-float 2> %t.log
 // RUN: grep '"-no-implicit-float"' %t.log
 
+// RUN: %clang -target armv7-apple-darwin10 -### -S -no-implicit-float %s 2> %t.log
+// RUN: grep '"-no-implicit-float"' %t.log | count 1