Correctly remove OptimizeForSize from functions marked OptimizeNone.

This allows using __attribute__((optnone)) and the -Os/-Oz options.
Fixes PR21604.

llvm-svn: 222683

1 files changed, 15 insertions, 10 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index b35e81c..497aac5 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -715,10 +715,6 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
     // Naked implies noinline: we should not be inlining such functions.
     B.addAttribute(llvm::Attribute::Naked);
     B.addAttribute(llvm::Attribute::NoInline);
-  } else if (D->hasAttr<OptimizeNoneAttr>()) {
-    // OptimizeNone implies noinline; we should not be inlining such functions.
-    B.addAttribute(llvm::Attribute::OptimizeNone);
-    B.addAttribute(llvm::Attribute::NoInline);
   } else if (D->hasAttr<NoDuplicateAttr>()) {
     B.addAttribute(llvm::Attribute::NoDuplicate);
   } else if (D->hasAttr<NoInlineAttr>()) {
@@ -738,12 +734,6 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
   if (D->hasAttr<MinSizeAttr>())
     B.addAttribute(llvm::Attribute::MinSize);
 
-  if (D->hasAttr<OptimizeNoneAttr>()) {
-    // OptimizeNone wins over OptimizeForSize and MinSize.
-    B.removeAttribute(llvm::Attribute::OptimizeForSize);
-    B.removeAttribute(llvm::Attribute::MinSize);
-  }
-
   if (LangOpts.getStackProtector() == LangOptions::SSPOn)
     B.addAttribute(llvm::Attribute::StackProtect);
   else if (LangOpts.getStackProtector() == LangOptions::SSPStrong)
@@ -772,6 +762,21 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
                    llvm::AttributeSet::get(
                        F->getContext(), llvm::AttributeSet::FunctionIndex, B));
 
+  if (D->hasAttr<OptimizeNoneAttr>()) {
+    // OptimizeNone implies noinline; we should not be inlining such functions.
+    F->addFnAttr(llvm::Attribute::OptimizeNone);
+    F->addFnAttr(llvm::Attribute::NoInline);
+
+    // OptimizeNone wins over OptimizeForSize, MinSize, AlwaysInline.
+    F->removeFnAttr(llvm::Attribute::OptimizeForSize);
+    F->removeFnAttr(llvm::Attribute::MinSize);
+    F->removeFnAttr(llvm::Attribute::AlwaysInline);
+
+    // Attribute 'inlinehint' has no effect on 'optnone' functions.
+    // Explicitly remove it from the set of function attributes.
+    F->removeFnAttr(llvm::Attribute::InlineHint);
+  }
+
   if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D))
     F->setUnnamedAddr(true);
   else if (const auto *MD = dyn_cast<CXXMethodDecl>(D))