[driver] Add -mglobal-merge/-mno-global-merge machine options to enable/disable merging of

globals during codegen.
Fixes <rdar://problem/10017909>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@138612 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 13 insertions, 0 deletions

diff --git a/lib/CodeGen/BackendUtil.cpp b/lib/CodeGen/BackendUtil.cpp
index 7546633256..9346cf3699 100644
--- a/lib/CodeGen/BackendUtil.cpp
+++ b/lib/CodeGen/BackendUtil.cpp
@@ -269,6 +269,8 @@ bool EmitAssemblyHelper::AddEmitPasses(BackendAction Action,
     BackendArgs.push_back("-time-passes");
   for (unsigned i = 0, e = CodeGenOpts.BackendOptions.size(); i != e; ++i)
     BackendArgs.push_back(CodeGenOpts.BackendOptions[i].c_str());
+  if (CodeGenOpts.NoGlobalMerge)
+    BackendArgs.push_back("-global-merge=false");
   BackendArgs.push_back(0);
   llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
                                     const_cast<char **>(&BackendArgs[0]));
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 33e11fb849..9e06f20561 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -677,6 +677,14 @@ void Clang::AddARMTargetArgs(const ArgList &Args,
     CmdArgs.push_back("-arm-darwin-use-movt=0");
 #endif
   }
+
+  // Setting -mno-global-merge disables the codegen global merge pass. Setting 
+  // -mglobal-merge has no effect as the pass is enabled by default.
+  if (Arg *A = Args.getLastArg(options::OPT_mglobal_merge,
+                               options::OPT_mno_global_merge)) {
+    if (A->getOption().matches(options::OPT_mno_global_merge))
+      CmdArgs.push_back("-mno-global-merge");
+  }
 }
 
 void Clang::AddMIPSTargetArgs(const ArgList &Args,
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index aee69083c1..64b5e83207 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -207,6 +207,8 @@ static void CodeGenOptsToArgs(const CodeGenOptions &Opts,
     Res.push_back("-mregparm");
     Res.push_back(llvm::utostr(Opts.NumRegisterParameters));
   }
+  if (Opts.NoGlobalMerge)
+    Res.push_back("-mno-global-merge");
   if (Opts.NoExecStack)
     Res.push_back("-mnoexecstack");
   if (Opts.RelaxAll)
@@ -1027,6 +1029,7 @@ static void ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   Opts.NoZeroInitializedInBSS = Args.hasArg(OPT_mno_zero_initialized_in_bss);
   Opts.BackendOptions = Args.getAllArgValues(OPT_backend_option);
   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.RelaxAll = Args.hasArg(OPT_mrelax_all);
   Opts.OmitLeafFramePointer = Args.hasArg(OPT_momit_leaf_frame_pointer);