Index: cfe/trunk/lib/Driver/ToolChains/Arch/ARM.cpp
===================================================================
--- cfe/trunk/lib/Driver/ToolChains/Arch/ARM.cpp
+++ cfe/trunk/lib/Driver/ToolChains/Arch/ARM.cpp
@@ -376,7 +376,11 @@
         Features.push_back(
             Args.MakeArgString((F.second ? "+" : "-") + F.first()));
   } else if (!CPUName.empty()) {
-    DecodeARMFeaturesFromCPU(D, CPUName, ExtensionFeatures);
+    // This sets the default features for the specified CPU. We certainly don't
+    // want to override the features that have been explicitly specified on the
+    // command line. Therefore, process them directly instead of appending them
+    // at the end later.
+    DecodeARMFeaturesFromCPU(D, CPUName, Features);
   }
 
   if (CPUArg)
Index: cfe/trunk/test/CodeGen/arm-target-features.c
===================================================================
--- cfe/trunk/test/CodeGen/arm-target-features.c
+++ cfe/trunk/test/CodeGen/arm-target-features.c
@@ -32,7 +32,7 @@
 
 // RUN: %clang_cc1 -triple thumbv8-linux-gnueabihf -target-cpu exynos-m4 -emit-llvm -o - %s | FileCheck %s --check-prefix=CHECK-BASIC-V82
 // RUN: %clang_cc1 -triple thumbv8-linux-gnueabihf -target-cpu exynos-m5 -emit-llvm -o - %s | FileCheck %s --check-prefix=CHECK-BASIC-V82
-// CHECK-BASIC-V82: "target-features"="+armv8.2-a,+crc,+crypto,+d32,+dotprod,+dsp,+fp-armv8,+fp-armv8d16,+fp-armv8d16sp,+fp-armv8sp,+fp16,+fp64,+fpregs,+hwdiv,+hwdiv-arm,+neon,+ras,+thumb-mode,+vfp2,+vfp2d16,+vfp2d16sp,+vfp2sp,+vfp3,+vfp3d16,+vfp3d16sp,+vfp3sp,+vfp4,+vfp4d16,+vfp4d16sp,+vfp4sp"
+// CHECK-BASIC-V82: "target-features"="+armv8.2-a,+crc,+crypto,+d32,+dotprod,+dsp,+fp-armv8,+fp-armv8d16,+fp-armv8d16sp,+fp-armv8sp,+fp16,+fp64,+fpregs,+fullfp16,+hwdiv,+hwdiv-arm,+neon,+ras,+thumb-mode,+vfp2,+vfp2d16,+vfp2d16sp,+vfp2sp,+vfp3,+vfp3d16,+vfp3d16sp,+vfp3sp,+vfp4,+vfp4d16,+vfp4d16sp,+vfp4sp"
 
 // RUN: %clang_cc1 -triple armv8-linux-gnueabi -target-cpu cortex-a53 -emit-llvm -o - %s | FileCheck %s --check-prefix=CHECK-BASIC-V8-ARM
 // CHECK-BASIC-V8-ARM: "target-features"="+armv8-a,+crc,+crypto,+d32,+dsp,+fp-armv8,+fp-armv8d16,+fp-armv8d16sp,+fp-armv8sp,+fp16,+fp64,+fpregs,+hwdiv,+hwdiv-arm,+neon,+vfp2,+vfp2d16,+vfp2d16sp,+vfp2sp,+vfp3,+vfp3d16,+vfp3d16sp,+vfp3sp,+vfp4,+vfp4d16,+vfp4d16sp,+vfp4sp,-thumb-mode"
Index: llvm/trunk/include/llvm/Support/ARMTargetParser.def
===================================================================
--- llvm/trunk/include/llvm/Support/ARMTargetParser.def
+++ llvm/trunk/include/llvm/Support/ARMTargetParser.def
@@ -148,6 +148,7 @@
 ARM_ARCH_EXT_NAME("dotprod",  ARM::AEK_DOTPROD,  "+dotprod","-dotprod")
 ARM_ARCH_EXT_NAME("dsp",      ARM::AEK_DSP,      "+dsp",   "-dsp")
 ARM_ARCH_EXT_NAME("fp",       ARM::AEK_FP,       nullptr,  nullptr)
+ARM_ARCH_EXT_NAME("fp.dp",    ARM::AEK_FP_DP,    nullptr,  nullptr)
 ARM_ARCH_EXT_NAME("mve",      ARM::AEK_SIMD,     "+mve",   "-mve")
 ARM_ARCH_EXT_NAME("mve.fp",   (ARM::AEK_SIMD | ARM::AEK_FP), "+mve.fp", "-mve.fp")
 ARM_ARCH_EXT_NAME("idiv",     (ARM::AEK_HWDIVARM | ARM::AEK_HWDIVTHUMB), nullptr, nullptr)
Index: llvm/trunk/lib/Support/ARMTargetParser.cpp
===================================================================
--- llvm/trunk/lib/Support/ARMTargetParser.cpp
+++ llvm/trunk/lib/Support/ARMTargetParser.cpp
@@ -409,30 +409,12 @@
   if (Extensions == AEK_INVALID)
     return false;
 
-  if (Extensions & AEK_CRC)
-    Features.push_back("+crc");
-  else
-    Features.push_back("-crc");
-
-  if (Extensions & AEK_DSP)
-    Features.push_back("+dsp");
-  else
-    Features.push_back("-dsp");
-
-  if (Extensions & AEK_FP16FML)
-    Features.push_back("+fp16fml");
-  else
-    Features.push_back("-fp16fml");
-
-  if (Extensions & AEK_RAS)
-    Features.push_back("+ras");
-  else
-    Features.push_back("-ras");
-
-  if (Extensions & AEK_DOTPROD)
-    Features.push_back("+dotprod");
-  else
-    Features.push_back("-dotprod");
+  for (const auto AE : ARCHExtNames) {
+    if ((Extensions & AE.ID) == AE.ID && AE.Feature)
+      Features.push_back(AE.Feature);
+    else if (AE.NegFeature)
+      Features.push_back(AE.NegFeature);
+  }
 
   return getHWDivFeatures(Extensions, Features);
 }
Index: llvm/trunk/unittests/Support/TargetParserTest.cpp
===================================================================
--- llvm/trunk/unittests/Support/TargetParserTest.cpp
+++ llvm/trunk/unittests/Support/TargetParserTest.cpp
@@ -571,17 +571,18 @@
 TEST(TargetParserTest, ARMExtensionFeatures) {
   std::map<unsigned, std::vector<StringRef>> Extensions;
 
-  Extensions[ARM::AEK_CRC]        = { "+crc",       "-crc" };
-  Extensions[ARM::AEK_DSP]        = { "+dsp",       "-dsp" };
+  for (auto &Ext : ARM::ARCHExtNames) {
+    if (Ext.Feature && Ext.NegFeature)
+      Extensions[Ext.ID] = { StringRef(Ext.Feature),
+                             StringRef(Ext.NegFeature) };
+  }
+
   Extensions[ARM::AEK_HWDIVARM]   = { "+hwdiv-arm", "-hwdiv-arm" };
   Extensions[ARM::AEK_HWDIVTHUMB] = { "+hwdiv",     "-hwdiv" };
-  Extensions[ARM::AEK_RAS]        = { "+ras",       "-ras" };
-  Extensions[ARM::AEK_FP16FML]    = { "+fp16fml",   "-fp16fml" };
-  Extensions[ARM::AEK_DOTPROD]    = { "+dotprod",   "-dotprod" };
 
   std::vector<StringRef> Features;
 
-  EXPECT_FALSE(AArch64::getExtensionFeatures(ARM::AEK_INVALID, Features));
+  EXPECT_FALSE(ARM::getExtensionFeatures(ARM::AEK_INVALID, Features));
 
   for (auto &E : Extensions) {
     // test +extension
@@ -598,7 +599,7 @@
     Found = std::find(std::begin(Features), std::end(Features), E.second.at(1));
     EXPECT_TRUE(Found != std::end(Features));
     EXPECT_TRUE(Extensions.size() == Features.size());
-   }
+  }
 }
 
 TEST(TargetParserTest, ARMFPUFeatures) {