1 files changed, 54 insertions, 25 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 64c2bd673cc..f66cfef7766 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -875,6 +875,13 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
     B.addAttribute(llvm::Attribute::StackProtectReq);
 
   if (!D) {
+    // If we don't have a declaration to control inlining, the function isn't
+    // explicitly marked as alwaysinline for semantic reasons, and inlining is
+    // disabled, mark the function as noinline.
+    if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline) &&
+        CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining)
+      B.addAttribute(llvm::Attribute::NoInline);
+
     F->addAttributes(llvm::AttributeSet::FunctionIndex,
                      llvm::AttributeSet::get(
                          F->getContext(),
@@ -882,7 +889,23 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
     return;
   }
 
-  if (D->hasAttr<NakedAttr>()) {
+  if (D->hasAttr<OptimizeNoneAttr>()) {
+    B.addAttribute(llvm::Attribute::OptimizeNone);
+
+    // OptimizeNone implies noinline; we should not be inlining such functions.
+    B.addAttribute(llvm::Attribute::NoInline);
+    assert(!F->hasFnAttribute(llvm::Attribute::AlwaysInline) &&
+           "OptimizeNone and AlwaysInline on same function!");
+
+    // We still need to handle naked functions even though optnone subsumes
+    // much of their semantics.
+    if (D->hasAttr<NakedAttr>())
+      B.addAttribute(llvm::Attribute::Naked);
+
+    // OptimizeNone wins over OptimizeForSize and MinSize.
+    F->removeFnAttr(llvm::Attribute::OptimizeForSize);
+    F->removeFnAttr(llvm::Attribute::MinSize);
+  } else if (D->hasAttr<NakedAttr>()) {
     // Naked implies noinline: we should not be inlining such functions.
     B.addAttribute(llvm::Attribute::Naked);
     B.addAttribute(llvm::Attribute::NoInline);
@@ -891,41 +914,47 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
   } else if (D->hasAttr<NoInlineAttr>()) {
     B.addAttribute(llvm::Attribute::NoInline);
   } else if (D->hasAttr<AlwaysInlineAttr>() &&
-             !F->getAttributes().hasAttribute(llvm::AttributeSet::FunctionIndex,
-                                              llvm::Attribute::NoInline)) {
+             !F->hasFnAttribute(llvm::Attribute::NoInline)) {
     // (noinline wins over always_inline, and we can't specify both in IR)
     B.addAttribute(llvm::Attribute::AlwaysInline);
+  } else if (CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining) {
+    // If we're not inlining, then force everything that isn't always_inline to
+    // carry an explicit noinline attribute.
+    if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline))
+      B.addAttribute(llvm::Attribute::NoInline);
+  } else {
+    // Otherwise, propagate the inline hint attribute and potentially use its
+    // absence to mark things as noinline.
+    if (auto *FD = dyn_cast<FunctionDecl>(D)) {
+      if (any_of(FD->redecls(), [&](const FunctionDecl *Redecl) {
+            return Redecl->isInlineSpecified();
+          })) {
+        B.addAttribute(llvm::Attribute::InlineHint);
+      } else if (CodeGenOpts.getInlining() ==
+                     CodeGenOptions::OnlyHintInlining &&
+                 !FD->isInlined() &&
+                 !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) {
+        B.addAttribute(llvm::Attribute::NoInline);
+      }
+    }
   }
 
-  if (D->hasAttr<ColdAttr>()) {
-    if (!D->hasAttr<OptimizeNoneAttr>())
+  // Add other optimization related attributes if we are optimizing this
+  // function.
+  if (!D->hasAttr<OptimizeNoneAttr>()) {
+    if (D->hasAttr<ColdAttr>()) {
       B.addAttribute(llvm::Attribute::OptimizeForSize);
-    B.addAttribute(llvm::Attribute::Cold);
-  }
+      B.addAttribute(llvm::Attribute::Cold);
+    }
 
-  if (D->hasAttr<MinSizeAttr>())
-    B.addAttribute(llvm::Attribute::MinSize);
+    if (D->hasAttr<MinSizeAttr>())
+      B.addAttribute(llvm::Attribute::MinSize);
+  }
 
   F->addAttributes(llvm::AttributeSet::FunctionIndex,
                    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);
-    assert(!F->hasFnAttribute(llvm::Attribute::AlwaysInline) &&
-           "OptimizeNone and AlwaysInline on same function!");
-
-    // Attribute 'inlinehint' has no effect on 'optnone' functions.
-    // Explicitly remove it from the set of function attributes.
-    F->removeFnAttr(llvm::Attribute::InlineHint);
-  }
-
   unsigned alignment = D->getMaxAlignment() / Context.getCharWidth();
   if (alignment)
     F->setAlignment(alignment);