[PowerPC] Secure PLT support

This patch supports secure PLT mode for PowerPC 32 architecture.

Differential Revision: https://reviews.llvm.org/D42112

llvm-svn: 328617
diff --git a/llvm/lib/Target/PowerPC/PPCSubtarget.h b/llvm/lib/Target/PowerPC/PPCSubtarget.h
index c351b5c..c576d69 100644
--- a/llvm/lib/Target/PowerPC/PPCSubtarget.h
+++ b/llvm/lib/Target/PowerPC/PPCSubtarget.h
@@ -133,6 +133,7 @@
   bool HasFloat128;
   bool IsISA3_0;
   bool UseLongCalls;
+  bool SecurePlt;
 
   POPCNTDKind HasPOPCNTD;
 
@@ -255,6 +256,7 @@
   bool hasOnlyMSYNC() const { return HasOnlyMSYNC; }
   bool isPPC4xx() const { return IsPPC4xx; }
   bool isPPC6xx() const { return IsPPC6xx; }
+  bool isSecurePlt() const {return SecurePlt; }
   bool isE500() const { return IsE500; }
   bool isFeatureMFTB() const { return FeatureMFTB; }
   bool isDeprecatedDST() const { return DeprecatedDST; }