[stackprotector] Add command line option -fstack-protector-strong

This option has the following effects:
 * It adds the sspstrong IR attribute to each function within the CU.
 * It defines the macro __SSP_STRONG__ with the value of 2.

Differential Revision: http://llvm-reviews.chandlerc.com/D2717

llvm-svn: 201120

4 files changed, 13 insertions, 4 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index c0c1219f8d2..7b1eab9721d 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -651,6 +651,8 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
 
   if (LangOpts.getStackProtector() == LangOptions::SSPOn)
     B.addAttribute(llvm::Attribute::StackProtect);
+  else if (LangOpts.getStackProtector() == LangOptions::SSPStrong)
+    B.addAttribute(llvm::Attribute::StackProtectStrong);
   else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
     B.addAttribute(llvm::Attribute::StackProtectReq);
 
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index d2bb9ba5327..5792f42b6fc 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -10,6 +10,7 @@
 #include "Tools.h"
 #include "InputInfo.h"
 #include "ToolChains.h"
+#include "clang/Basic/LangOptions.h"
 #include "clang/Basic/ObjCRuntime.h"
 #include "clang/Basic/Version.h"
 #include "clang/Driver/Action.h"
@@ -3114,11 +3115,14 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   unsigned StackProtectorLevel = 0;
   if (Arg *A = Args.getLastArg(options::OPT_fno_stack_protector,
                                options::OPT_fstack_protector_all,
+                               options::OPT_fstack_protector_strong,
                                options::OPT_fstack_protector)) {
     if (A->getOption().matches(options::OPT_fstack_protector))
-      StackProtectorLevel = 1;
+      StackProtectorLevel = LangOptions::SSPOn;
+    else if (A->getOption().matches(options::OPT_fstack_protector_strong))
+      StackProtectorLevel = LangOptions::SSPStrong;
     else if (A->getOption().matches(options::OPT_fstack_protector_all))
-      StackProtectorLevel = 2;
+      StackProtectorLevel = LangOptions::SSPReq;
   } else {
     StackProtectorLevel =
       getToolChain().GetDefaultStackProtectorLevel(KernelOrKext);
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 3c75dd5249e..034730fe187 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1435,7 +1435,8 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
     break;
   case 0: Opts.setStackProtector(LangOptions::SSPOff); break;
   case 1: Opts.setStackProtector(LangOptions::SSPOn);  break;
-  case 2: Opts.setStackProtector(LangOptions::SSPReq); break;
+  case 2: Opts.setStackProtector(LangOptions::SSPStrong); break;
+  case 3: Opts.setStackProtector(LangOptions::SSPReq); break;
   }
 
   // Parse -fsanitize= arguments.
diff --git a/clang/lib/Frontend/InitPreprocessor.cpp b/clang/lib/Frontend/InitPreprocessor.cpp
index 7b3166da081..f975c9f6955 100644
--- a/clang/lib/Frontend/InitPreprocessor.cpp
+++ b/clang/lib/Frontend/InitPreprocessor.cpp
@@ -695,8 +695,10 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
 
   if (LangOpts.getStackProtector() == LangOptions::SSPOn)
     Builder.defineMacro("__SSP__");
+  else if (LangOpts.getStackProtector() == LangOptions::SSPStrong)
+    Builder.defineMacro("__SSP_STRONG__", "2");
   else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
-    Builder.defineMacro("__SSP_ALL__", "2");
+    Builder.defineMacro("__SSP_ALL__", "3");
 
   if (FEOpts.ProgramAction == frontend::RewriteObjC)
     Builder.defineMacro("__weak", "__attribute__((objc_gc(weak)))");