Plumb through the -fsplit-stack option using the existing backend

support.

Caveat: Other than the existing segmented stacks support, no
claims are made of this working.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178744 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 6 insertions, 0 deletions

diff --git a/lib/CodeGen/BackendUtil.cpp b/lib/CodeGen/BackendUtil.cpp
index 019570ce23..45079c0989 100644
--- a/lib/CodeGen/BackendUtil.cpp
+++ b/lib/CodeGen/BackendUtil.cpp
@@ -457,6 +457,7 @@ TargetMachine *EmitAssemblyHelper::CreateTargetMachine(bool MustCreateTM) {
   Options.TrapFuncName = CodeGenOpts.TrapFuncName;
   Options.PositionIndependentExecutable = LangOpts.PIELevel != 0;
   Options.SSPBufferSize = CodeGenOpts.SSPBufferSize;
+  Options.EnableSegmentedStacks = CodeGenOpts.EnableSegmentedStacks;
 
   TargetMachine *TM = TheTarget->createTargetMachine(Triple, TargetOpts.CPU,
                                                      FeaturesStr, Options,
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 5ddb95c022..83c140d2b3 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -2112,6 +2112,10 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
                     options::OPT_fno_optimize_sibling_calls))
     CmdArgs.push_back("-mdisable-tail-calls");
 
+  // Handle segmented stacks.
+  if (Args.hasArg(options::OPT_fsplit_stack))
+    CmdArgs.push_back("-split-stacks");
+  
   // Handle various floating point optimization flags, mapping them to the
   // appropriate LLVM code generation flags. The pattern for all of these is to
   // default off the codegen optimizations, and if any flag enables them and no
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index fbf0349978..611e784814 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -358,6 +358,7 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   Opts.NumRegisterParameters = Args.getLastArgIntValue(OPT_mregparm, 0, Diags);
   Opts.NoGlobalMerge = Args.hasArg(OPT_mno_global_merge);
   Opts.NoExecStack = Args.hasArg(OPT_mno_exec_stack);
+  Opts.EnableSegmentedStacks = Args.hasArg(OPT_split_stacks);
   Opts.RelaxAll = Args.hasArg(OPT_mrelax_all);
   Opts.OmitLeafFramePointer = Args.hasArg(OPT_momit_leaf_frame_pointer);
   Opts.SaveTempLabels = Args.hasArg(OPT_msave_temp_labels);