commit 945bc50f218290b92adc81129f2b67f6a6dd0f56
author Teresa Johnson <tejohnson@google.com> Thu Oct 15 20:35:53 2015 +0000
committer Teresa Johnson <tejohnson@google.com> Thu Oct 15 20:35:53 2015 +0000
tree b1d6cc3e1654288710358110ff073f5ecc89287d
parent 3b82908f0f0bae1c6be837be63ac2dff40dba539

Recommit "Clang support for -flto=thin."

This recommits r250398 with fixes to the tests for bot failures.

Add "-target x86_64-unknown-linux" to the clang invocations that
check for the gold plugin.

llvm-svn: 250455

clang/lib/Driver/Driver.cpp

diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index 0b842cd..fb5d38a 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -50,7 +50,8 @@
                DiagnosticsEngine &Diags,
                IntrusiveRefCntPtr<vfs::FileSystem> VFS)
     : Opts(createDriverOptTable()), Diags(Diags), VFS(VFS), Mode(GCCMode),
-      SaveTemps(SaveTempsNone), ClangExecutable(ClangExecutable),
+      SaveTemps(SaveTempsNone), LTOMode(LTOK_None),
+      ClangExecutable(ClangExecutable),
       SysRoot(DEFAULT_SYSROOT), UseStdLib(true),
       DefaultTargetTriple(DefaultTargetTriple),
       DriverTitle("clang LLVM compiler"), CCPrintOptionsFilename(nullptr),
@@ -366,6 +367,31 @@
   return Target;
 }
 
+// \brief Parse the LTO options and record the type of LTO compilation
+// based on which -f(no-)?lto(=.*)? option occurs last.
+void Driver::setLTOMode(const llvm::opt::ArgList &Args) {
+  LTOMode = LTOK_None;
+  if (!Args.hasFlag(options::OPT_flto, options::OPT_flto_EQ,
+                    options::OPT_fno_lto, false))
+    return;
+
+  StringRef LTOName("full");
+
+  const Arg *A = Args.getLastArg(options::OPT_flto_EQ);
+  if (A) LTOName = A->getValue();
+
+  LTOMode = llvm::StringSwitch<LTOKind>(LTOName)
+                .Case("full", LTOK_Full)
+                .Case("thin", LTOK_Thin)
+                .Default(LTOK_Unknown);
+
+  if (LTOMode == LTOK_Unknown) {
+    assert(A);
+    Diag(diag::err_drv_unsupported_option_argument) << A->getOption().getName()
+                                                    << A->getValue();
+  }
+}
+
 Compilation *Driver::BuildCompilation(ArrayRef<const char *> ArgList) {
   llvm::PrettyStackTraceString CrashInfo("Compilation construction");
 
@@ -449,6 +475,8 @@
                     .Default(SaveTempsCwd);
   }
 
+  setLTOMode(Args);
+
   std::unique_ptr<llvm::opt::InputArgList> UArgs =
       llvm::make_unique<InputArgList>(std::move(Args));
 
@@ -1567,7 +1595,7 @@
                                                types::TY_LLVM_BC);
   }
   case phases::Backend: {
-    if (IsUsingLTO(Args)) {
+    if (isUsingLTO()) {
       types::ID Output =
           Args.hasArg(options::OPT_S) ? types::TY_LTO_IR : types::TY_LTO_BC;
       return llvm::make_unique<BackendJobAction>(std::move(Input), Output);
@@ -1588,10 +1616,6 @@
   llvm_unreachable("invalid phase in ConstructPhaseAction");
 }
 
-bool Driver::IsUsingLTO(const ArgList &Args) const {
-  return Args.hasFlag(options::OPT_flto, options::OPT_fno_lto, false);
-}
-
 void Driver::BuildJobs(Compilation &C) const {
   llvm::PrettyStackTraceString CrashInfo("Building compilation jobs");