[CodeGen] Reland r330442: Add an option to suppress output of llvm.ident

The test case in the original patch was overly contrained and
failed on PPC targets.

llvm-svn: 330575

7 files changed, 33 insertions, 3 deletions

diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index c97324441b0..e3ced42154c 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -396,7 +396,10 @@ def O_flag : Flag<["-"], "O">, Flags<[CC1Option]>, Alias<O>, AliasArgs<["2"]>;
 def Ofast : Joined<["-"], "Ofast">, Group<O_Group>, Flags<[CC1Option]>;
 def P : Flag<["-"], "P">, Flags<[CC1Option]>, Group<Preprocessor_Group>,
   HelpText<"Disable linemarker output in -E mode">;
-def Qn : Flag<["-"], "Qn">, IgnoredGCCCompat;
+def Qy : Flag<["-"], "Qy">, Flags<[CC1Option]>,
+  HelpText<"Emit metadata containing compiler name and version">;
+def Qn : Flag<["-"], "Qn">, Flags<[CC1Option]>,
+  HelpText<"Do not emit metadata containing compiler name and version">;
 def Qunused_arguments : Flag<["-"], "Qunused-arguments">, Flags<[DriverOption, CoreOption]>,
   HelpText<"Don't emit warning for unused driver arguments">;
 def Q : Flag<["-"], "Q">, IgnoredGCCCompat;
diff --git a/clang/include/clang/Frontend/CodeGenOptions.def b/clang/include/clang/Frontend/CodeGenOptions.def
index 684f99e1de3..1684dbdb557 100644
--- a/clang/include/clang/Frontend/CodeGenOptions.def
+++ b/clang/include/clang/Frontend/CodeGenOptions.def
@@ -69,6 +69,7 @@ CODEGENOPT(EmitDeclMetadata  , 1, 0) ///< Emit special metadata indicating what
                                      ///< Decl* various IR entities came from.
                                      ///< Only useful when running CodeGen as a
                                      ///< subroutine.
+CODEGENOPT(EmitVersionIdentMetadata , 1, 1) ///< Emit compiler version metadata.
 CODEGENOPT(EmitGcovArcs      , 1, 0) ///< Emit coverage data files, aka. GCDA.
 CODEGENOPT(EmitGcovNotes     , 1, 0) ///< Emit coverage "notes" files, aka GCNO.
 CODEGENOPT(EmitOpenCLArgMetadata , 1, 0) ///< Emit OpenCL kernel arg metadata.
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index bdd326d70e4..474018c065e 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -577,7 +577,8 @@ void CGDebugInfo::CreateCompileUnit() {
                           remapDIPath(getCurrentDirname()),
                           CSInfo,
                           getSource(SM, SM.getMainFileID())),
-      Producer, LO.Optimize || CGOpts.PrepareForLTO || CGOpts.EmitSummaryIndex,
+      CGOpts.EmitVersionIdentMetadata ? Producer : "",
+      LO.Optimize || CGOpts.PrepareForLTO || CGOpts.EmitSummaryIndex,
       CGOpts.DwarfDebugFlags, RuntimeVers,
       CGOpts.EnableSplitDwarf ? "" : CGOpts.SplitDwarfFile, EmissionKind,
       0 /* DWOid */, CGOpts.SplitDwarfInlining, CGOpts.DebugInfoForProfiling,
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 63fcc8fbce0..063b9be4cd0 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -571,7 +571,8 @@ void CodeGenModule::Release() {
   if (DebugInfo)
     DebugInfo->finalize();
 
-  EmitVersionIdentMetadata();
+  if (getCodeGenOpts().EmitVersionIdentMetadata)
+    EmitVersionIdentMetadata();
 
   EmitTargetMetadata();
 }
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index a3cb0f21ed5..6c5e2caae4a 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -4408,6 +4408,9 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     }
   }
 
+  if (!Args.hasFlag(options::OPT_Qy, options::OPT_Qn, true))
+    CmdArgs.push_back("-Qn");
+
   // -fcommon is the default unless compiling kernel code or the target says so
   bool NoCommonDefault = KernelOrKext || isNoCommonDefault(RawTriple);
   if (!Args.hasFlag(options::OPT_fcommon, options::OPT_fno_common,
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 67e15b41add..f904e65e724 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1112,6 +1112,8 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   Opts.EmitCheckPathComponentsToStrip = getLastArgIntValue(
       Args, OPT_fsanitize_undefined_strip_path_components_EQ, 0, Diags);
 
+  Opts.EmitVersionIdentMetadata = Args.hasFlag(OPT_Qy, OPT_Qn, true);
+
   return Success;
 }
 
diff --git a/clang/test/CodeGen/no-ident-version.c b/clang/test/CodeGen/no-ident-version.c
new file mode 100644
index 00000000000..ad2a7db2d3d
--- /dev/null
+++ b/clang/test/CodeGen/no-ident-version.c
@@ -0,0 +1,19 @@
+// RUN: %clang_cc1 -emit-llvm -debug-info-kind=limited -o - %s \
+// RUN:   | FileCheck --check-prefix=CHECK-NONE %s
+// RUN: %clang_cc1 -Qn -emit-llvm -debug-info-kind=limited -o - %s \
+// RUN:   | FileCheck --check-prefix=CHECK-QN %s
+// RUN: %clang_cc1 -Qy -emit-llvm -debug-info-kind=limited -o - %s \
+// RUN:   | FileCheck --check-prefix=CHECK-QY %s
+
+// CHECK-NONE: @main
+// CHECK-NONE: llvm.ident
+// CHECK-NONE: producer:
+
+// CHECK-QN: @main
+// CHECK-QN-NOT: llvm.ident
+// CHECK-QN-NOT: producer:
+
+// CHECK-QY: @main
+// CHECK-QY: llvm.ident
+// CHECK-QY: producer:
+int main(void) {}