Add -femit-all-decls codegen option.

 - Emits all declarations, even unused (static) ones.
 - Useful when doing minimization of codegen problems (otherwise
   problems localized to a static function aren't minimized well).

llvm-svn: 63776

3 files changed, 10 insertions, 1 deletions

diff --git a/clang/Driver/clang.cpp b/clang/Driver/clang.cpp
index c6fee1f09e5..bf885ea464f 100644
--- a/clang/Driver/clang.cpp
+++ b/clang/Driver/clang.cpp
@@ -500,6 +500,9 @@ static llvm::cl::opt<bool>
 ObjCNonFragileABI("fobjc-nonfragile-abi",
                   llvm::cl::desc("enable objective-c's nonfragile abi"));
 
+static llvm::cl::opt<bool>
+EmitAllDecls("femit-all-decls",
+              llvm::cl::desc("Emit all declarations, even if unused"));
 
 // FIXME: This (and all GCC -f options) really come in -f... and
 // -fno-... forms, and additionally support automagic behavior when
@@ -635,6 +638,9 @@ static void InitializeLanguageStandard(LangOptions &Options, LangKind LK,
 
   if (ObjCNonFragileABI)
     Options.ObjCNonFragileABI = 1;
+
+  if (EmitAllDecls)
+    Options.EmitAllDecls = 1;
 }
 
 static llvm::cl::opt<bool>
diff --git a/clang/include/clang/Basic/LangOptions.h b/clang/include/clang/Basic/LangOptions.h
index b615412f20b..b85a74bc4ab 100644
--- a/clang/include/clang/Basic/LangOptions.h
+++ b/clang/include/clang/Basic/LangOptions.h
@@ -51,6 +51,8 @@ struct LangOptions {
   unsigned ThreadsafeStatics : 1; // Whether static initializers are protected
                                   // by locks.
   unsigned Blocks            : 1; // block extension to C
+  unsigned EmitAllDecls      : 1; // Emit all declarations, even if
+                                  // they are unused.
 private:
   unsigned GC : 2; // Objective-C Garbage Collection modes.  We declare
                    // this enum as unsigned because MSVC insists on making enums
@@ -72,6 +74,7 @@ public:
     // FIXME: The default should be 1.
     ThreadsafeStatics = 0;
     Blocks = 0;
+    EmitAllDecls = 0;
   }
   
   GCMode getGCMode() const { return (GCMode) GC; }
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 18870722fa2..af70a9c8464 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -468,7 +468,7 @@ void CodeGenModule::EmitGlobal(const ValueDecl *Global) {
 
   // If the global is a static, defer code generation until later so
   // we can easily omit unused statics.
-  if (isStatic) {
+  if (isStatic && !Features.EmitAllDecls) {
     StaticDecls.push_back(Global);
     return;
   }