CodeGen: Refactor SetLLVMFunctionAttributesForDefinition to use an AttrBuilder.

Adding attributes to a uniqued set has become expensive, don't do it more often
than necessary. No functionality change.

llvm-svn: 181662

1 files changed, 31 insertions, 27 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 717ed17dd4e..695048e5b32 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -598,61 +598,65 @@ static bool hasUnwindExceptions(const LangOptions &LangOpts) {
 
 void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
                                                            llvm::Function *F) {
+  llvm::AttrBuilder B;
+
   if (CodeGenOpts.UnwindTables)
-    F->setHasUWTable();
+    B.addAttribute(llvm::Attribute::UWTable);
 
   if (!hasUnwindExceptions(LangOpts))
-    F->addFnAttr(llvm::Attribute::NoUnwind);
+    B.addAttribute(llvm::Attribute::NoUnwind);
 
   if (D->hasAttr<NakedAttr>()) {
     // Naked implies noinline: we should not be inlining such functions.
-    F->addFnAttr(llvm::Attribute::Naked);
-    F->addFnAttr(llvm::Attribute::NoInline);
+    B.addAttribute(llvm::Attribute::Naked);
+    B.addAttribute(llvm::Attribute::NoInline);
+  } else if (D->hasAttr<NoInlineAttr>()) {
+    B.addAttribute(llvm::Attribute::NoInline);
+  } else if ((D->hasAttr<AlwaysInlineAttr>() ||
+              D->hasAttr<ForceInlineAttr>()) &&
+             !F->getAttributes().hasAttribute(llvm::AttributeSet::FunctionIndex,
+                                              llvm::Attribute::NoInline)) {
+    // (noinline wins over always_inline, and we can't specify both in IR)
+    B.addAttribute(llvm::Attribute::AlwaysInline);
   }
 
-  if (D->hasAttr<NoInlineAttr>())
-    F->addFnAttr(llvm::Attribute::NoInline);
-
-  // (noinline wins over always_inline, and we can't specify both in IR)
-  if ((D->hasAttr<AlwaysInlineAttr>() || D->hasAttr<ForceInlineAttr>()) &&
-      !F->getAttributes().hasAttribute(llvm::AttributeSet::FunctionIndex,
-                                       llvm::Attribute::NoInline))
-    F->addFnAttr(llvm::Attribute::AlwaysInline);
-
   // FIXME: Communicate hot and cold attributes to LLVM more directly.
   if (D->hasAttr<ColdAttr>())
-    F->addFnAttr(llvm::Attribute::OptimizeForSize);
+    B.addAttribute(llvm::Attribute::OptimizeForSize);
 
   if (D->hasAttr<MinSizeAttr>())
-    F->addFnAttr(llvm::Attribute::MinSize);
-
-  if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D))
-    F->setUnnamedAddr(true);
-
-  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D))
-    if (MD->isVirtual())
-      F->setUnnamedAddr(true);
+    B.addAttribute(llvm::Attribute::MinSize);
 
   if (LangOpts.getStackProtector() == LangOptions::SSPOn)
-    F->addFnAttr(llvm::Attribute::StackProtect);
+    B.addAttribute(llvm::Attribute::StackProtect);
   else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
-    F->addFnAttr(llvm::Attribute::StackProtectReq);
+    B.addAttribute(llvm::Attribute::StackProtectReq);
 
   // Add sanitizer attributes if function is not blacklisted.
   if (!SanitizerBlacklist.isIn(*F)) {
     // When AddressSanitizer is enabled, set SanitizeAddress attribute
     // unless __attribute__((no_sanitize_address)) is used.
     if (SanOpts.Address && !D->hasAttr<NoSanitizeAddressAttr>())
-      F->addFnAttr(llvm::Attribute::SanitizeAddress);
+      B.addAttribute(llvm::Attribute::SanitizeAddress);
     // Same for ThreadSanitizer and __attribute__((no_sanitize_thread))
     if (SanOpts.Thread && !D->hasAttr<NoSanitizeThreadAttr>()) {
-      F->addFnAttr(llvm::Attribute::SanitizeThread);
+      B.addAttribute(llvm::Attribute::SanitizeThread);
     }
     // Same for MemorySanitizer and __attribute__((no_sanitize_memory))
     if (SanOpts.Memory && !D->hasAttr<NoSanitizeMemoryAttr>())
-      F->addFnAttr(llvm::Attribute::SanitizeMemory);
+      B.addAttribute(llvm::Attribute::SanitizeMemory);
   }
 
+  F->addAttributes(llvm::AttributeSet::FunctionIndex,
+                   llvm::AttributeSet::get(
+                       F->getContext(), llvm::AttributeSet::FunctionIndex, B));
+
+  if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D))
+    F->setUnnamedAddr(true);
+  else if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D))
+    if (MD->isVirtual())
+      F->setUnnamedAddr(true);
+
   unsigned alignment = D->getMaxAlignment() / Context.getCharWidth();
   if (alignment)
     F->setAlignment(alignment);