[driver] When using the -mfpmath= option, add an error message when trying to

enable neonfp on a CPU that doesn't support NEON.
rdar://11108618


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154061 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 15 insertions, 3 deletions

diff --git a/include/clang/Basic/DiagnosticDriverKinds.td b/include/clang/Basic/DiagnosticDriverKinds.td
index a66e9f7e5a..b44315932c 100644
--- a/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/include/clang/Basic/DiagnosticDriverKinds.td
@@ -71,6 +71,8 @@ def err_drv_invalid_mfloat_abi : Error<
   "invalid float ABI '%0'">;
 def err_drv_invalid_libcxx_deployment : Error<
   "invalid deployment target for -stdlib=libc++ (requires %0 or later)">;
+def err_drv_invalid_feature : Error<
+  "invalid feature '%0' for CPU '%1'">;
 
 def err_drv_I_dash_not_supported : Error<
   "'%0' not supported, please use -iquote instead">;
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index dda884303a..84021084ca 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -547,17 +547,23 @@ static void addFPUArgs(const Driver &D, const Arg *A, const ArgList &Args,
 
 // Handle -mfpmath=.
 static void addFPMathArgs(const Driver &D, const Arg *A, const ArgList &Args,
-                          ArgStringList &CmdArgs) {
+                          ArgStringList &CmdArgs, StringRef CPU) {
   StringRef FPMath = A->getValue(Args);
   
   // Set the target features based on the FPMath.
   if (FPMath == "neon") {
     CmdArgs.push_back("-target-feature");
     CmdArgs.push_back("+neonfp");
+    
+    if (CPU != "cortex-a8" && CPU != "cortex-a9" && CPU != "cortex-a9-mp")    
+      D.Diag(diag::err_drv_invalid_feature) << "-mfpmath=neon" << CPU;
+    
   } else if (FPMath == "vfp" || FPMath == "vfp2" || FPMath == "vfp3" ||
              FPMath == "vfp4") {
     CmdArgs.push_back("-target-feature");
     CmdArgs.push_back("-neonfp");
+
+    // FIXME: Add warnings when disabling a feature not present for a given CPU.    
   } else
     D.Diag(diag::err_drv_clang_unsupported) << A->getAsString(Args);
 }
@@ -710,7 +716,7 @@ void Clang::AddARMTargetArgs(const ArgList &Args,
 
   // Honor -mfpmath=.
   if (const Arg *A = Args.getLastArg(options::OPT_mfpmath_EQ))
-    addFPMathArgs(D, A, Args, CmdArgs);
+    addFPMathArgs(D, A, Args, CmdArgs, getARMTargetCPU(Args, Triple));
 
   // Setting -msoft-float effectively disables NEON because of the GCC
   // implementation, although the same isn't true of VFP or VFP3.
@@ -2681,7 +2687,7 @@ void ClangAs::AddARMTargetArgs(const ArgList &Args,
 
   // Honor -mfpmath=.
   if (const Arg *A = Args.getLastArg(options::OPT_mfpmath_EQ))
-    addFPMathArgs(D, A, Args, CmdArgs);
+    addFPMathArgs(D, A, Args, CmdArgs, getARMTargetCPU(Args, Triple));
 }
 
 void ClangAs::ConstructJob(Compilation &C, const JobAction &JA,
diff --git a/test/Driver/arm-mfpmath.c b/test/Driver/arm-mfpmath.c
index ab1809385a..0421046c5b 100644
--- a/test/Driver/arm-mfpmath.c
+++ b/test/Driver/arm-mfpmath.c
@@ -23,3 +23,7 @@
 // RUN: %clang -target arm-apple-darwin10 -mfpmath=foo %s -### -c -o %t.o 2>&1 \
 // RUN:   | FileCheck --check-prefix=CHECK-ERROR %s
 // CHECK-ERROR: clang compiler does not support '-mfpmath=foo'
+
+// RUN: %clang -target arm-apple-darwin10 -mcpu=arm1136j-s -mfpmath=neon %s -### -c -o %t.o 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK-MCPU-ERROR %s
+// CHECK-MCPU-ERROR: error: invalid feature '-mfpmath=neon' for CPU 'arm1136j-s'