From 4fbead8a5ef5f4ae61437f129e53df6fbf3be1d5 Mon Sep 17 00:00:00 2001
From: Renato Golin <renato.golin@linaro.org>
Date: Thu, 30 Jul 2015 16:40:17 +0000
Subject: [PATCH] [ARM] Allow setting the generic features for native cpus

Copying the already existing code for x86 to ARM to set the correct CPU
features when using -mcpu=native. We can already detect the CPU name
but we were not setting the correct feature bits.

Moving fpu/hwdiv down to make sure they override whatever we set the
default to be.

No tests because this is native detection, and not all ARM-enabled builds
will hapen at a specific CPU, or even ARM. I have tested locally and it
works as expected.

Fixes PR12794.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@243656 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Driver/Tools.cpp | 55 ++++++++++++++++++++++++++------------------
 1 file changed, 32 insertions(+), 23 deletions(-)

diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 4dbc541934..8bbc92db65 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -715,29 +715,6 @@ static void getARMTargetFeatures(const Driver &D, const llvm::Triple &Triple,
     }
   }
 
-  // Honor -mfpu=. ClangAs gives preference to -Wa,-mfpu=.
-  const Arg *FPUArg = Args.getLastArg(options::OPT_mfpu_EQ);
-  if (WaFPU) {
-    if (FPUArg)
-      D.Diag(clang::diag::warn_drv_unused_argument)
-          << FPUArg->getAsString(Args);
-    getARMFPUFeatures(D, WaFPU, Args, StringRef(WaFPU->getValue()).substr(6),
-                      Features);
-  } else if (FPUArg) {
-    getARMFPUFeatures(D, FPUArg, Args, FPUArg->getValue(), Features);
-  }
-
-  // Honor -mhwdiv=. ClangAs gives preference to -Wa,-mhwdiv=.
-  const Arg *HDivArg = Args.getLastArg(options::OPT_mhwdiv_EQ);
-  if (WaHDiv) {
-    if (HDivArg)
-      D.Diag(clang::diag::warn_drv_unused_argument)
-          << HDivArg->getAsString(Args);
-    getARMHWDivFeatures(D, WaHDiv, Args,
-                        StringRef(WaHDiv->getValue()).substr(8), Features);
-  } else if (HDivArg)
-    getARMHWDivFeatures(D, HDivArg, Args, HDivArg->getValue(), Features);
-
   // Check -march. ClangAs gives preference to -Wa,-march=.
   const Arg *ArchArg = Args.getLastArg(options::OPT_march_EQ);
   StringRef ArchName;
@@ -768,6 +745,38 @@ static void getARMTargetFeatures(const Driver &D, const llvm::Triple &Triple,
     checkARMCPUName(D, CPUArg, Args, CPUName, ArchName, Triple);
   }
 
+  // Add CPU features for generic CPUs
+  if (CPUName == "native") {
+    llvm::StringMap<bool> HostFeatures;
+    if (llvm::sys::getHostCPUFeatures(HostFeatures))
+      for (auto &F : HostFeatures)
+        Features.push_back(
+            Args.MakeArgString((F.second ? "+" : "-") + F.first()));
+  }
+
+  // Honor -mfpu=. ClangAs gives preference to -Wa,-mfpu=.
+  const Arg *FPUArg = Args.getLastArg(options::OPT_mfpu_EQ);
+  if (WaFPU) {
+    if (FPUArg)
+      D.Diag(clang::diag::warn_drv_unused_argument)
+          << FPUArg->getAsString(Args);
+    getARMFPUFeatures(D, WaFPU, Args, StringRef(WaFPU->getValue()).substr(6),
+                      Features);
+  } else if (FPUArg) {
+    getARMFPUFeatures(D, FPUArg, Args, FPUArg->getValue(), Features);
+  }
+
+  // Honor -mhwdiv=. ClangAs gives preference to -Wa,-mhwdiv=.
+  const Arg *HDivArg = Args.getLastArg(options::OPT_mhwdiv_EQ);
+  if (WaHDiv) {
+    if (HDivArg)
+      D.Diag(clang::diag::warn_drv_unused_argument)
+          << HDivArg->getAsString(Args);
+    getARMHWDivFeatures(D, WaHDiv, Args,
+                        StringRef(WaHDiv->getValue()).substr(8), Features);
+  } else if (HDivArg)
+    getARMHWDivFeatures(D, HDivArg, Args, HDivArg->getValue(), Features);
+
   // Setting -msoft-float effectively disables NEON because of the GCC
   // implementation, although the same isn't true of VFP or VFP3.
   if (FloatABI == "soft") {
-- 
2.40.0