Use atomic instructions on linux thumb v7.

This matches gcc's behaviour. The patch also explicitly parses the version so
that this keeps working when we add support for v8.

llvm-svn: 181750

1 files changed, 17 insertions, 3 deletions

diff --git a/clang/lib/Basic/Targets.cpp b/clang/lib/Basic/Targets.cpp
index 841ca62ab6e..a622a11aa5a 100644
--- a/clang/lib/Basic/Targets.cpp
+++ b/clang/lib/Basic/Targets.cpp
@@ -3536,9 +3536,23 @@ class ARMTargetInfo : public TargetInfo {
     if (T.getOS() != llvm::Triple::Linux)
      return false;
     StringRef ArchName = T.getArchName();
-    if (ArchName.startswith("armv6") || ArchName.startswith("armv7"))
-      return true;
-    return false;
+    if (T.getArch() == llvm::Triple::arm) {
+      if (!ArchName.startswith("armv"))
+        return false;
+      StringRef VersionStr = ArchName.substr(4);
+      unsigned Version;
+      if (VersionStr.getAsInteger(10, Version))
+        return false;
+      return Version >= 6;
+    }
+    assert(T.getArch() == llvm::Triple::thumb);
+    if (!ArchName.startswith("thumbv"))
+      return false;
+    StringRef VersionStr = ArchName.substr(6);
+    unsigned Version;
+    if (VersionStr.getAsInteger(10, Version))
+      return false;
+    return Version >= 7;
   }
 
 public: