Added support for the Builtin attribute.

The Builtin attribute is an attribute that can be placed on function call site that signal that even though a function is declared as being a builtin,

rdar://problem/13727199

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185049 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 21 insertions, 2 deletions

diff --git a/lib/IR/Attributes.cpp b/lib/IR/Attributes.cpp
index e48ebb1..2160ea2 100644
--- a/lib/IR/Attributes.cpp
+++ b/lib/IR/Attributes.cpp
@@ -157,6 +157,8 @@ std::string Attribute::getAsString(bool InAttrGrp) const {
     return "sanitize_address";
   if (hasAttribute(Attribute::AlwaysInline))
     return "alwaysinline";
+  if (hasAttribute(Attribute::Builtin))
+    return "builtin";
   if (hasAttribute(Attribute::ByVal))
     return "byval";
   if (hasAttribute(Attribute::InlineHint))
@@ -399,6 +401,7 @@ uint64_t AttributeImpl::getAttrMask(Attribute::AttrKind Val) {
   case Attribute::NoBuiltin:       return 1ULL << 38;
   case Attribute::Returned:        return 1ULL << 39;
   case Attribute::Cold:            return 1ULL << 40;
+  case Attribute::Builtin:         return 1ULL << 41;
   }
   llvm_unreachable("Unsupported attribute type");
 }
diff --git a/lib/IR/Instructions.cpp b/lib/IR/Instructions.cpp
index d58877e..5878f77 100644
--- a/lib/IR/Instructions.cpp
+++ b/lib/IR/Instructions.cpp
@@ -346,7 +346,7 @@ void CallInst::removeAttribute(unsigned i, Attribute attr) {
   setAttributes(PAL);
 }
 
-bool CallInst::hasFnAttr(Attribute::AttrKind A) const {
+bool CallInst::hasFnAttrImpl(Attribute::AttrKind A) const {
   if (AttributeList.hasAttribute(AttributeSet::FunctionIndex, A))
     return true;
   if (const Function *F = getCalledFunction())
@@ -574,7 +574,7 @@ void InvokeInst::setSuccessorV(unsigned idx, BasicBlock *B) {
   return setSuccessor(idx, B);
 }
 
-bool InvokeInst::hasFnAttr(Attribute::AttrKind A) const {
+bool InvokeInst::hasFnAttrImpl(Attribute::AttrKind A) const {
   if (AttributeList.hasAttribute(AttributeSet::FunctionIndex, A))
     return true;
   if (const Function *F = getCalledFunction())
diff --git a/lib/IR/Verifier.cpp b/lib/IR/Verifier.cpp
index 1b1b3b8..7123eaf 100644
--- a/lib/IR/Verifier.cpp
+++ b/lib/IR/Verifier.cpp
@@ -692,6 +692,7 @@ void Verifier::VerifyAttributeTypes(AttributeSet Attrs, unsigned Idx,
         I->getKindAsEnum() == Attribute::SanitizeMemory ||
         I->getKindAsEnum() == Attribute::MinSize ||
         I->getKindAsEnum() == Attribute::NoDuplicate ||
+        I->getKindAsEnum() == Attribute::Builtin ||
         I->getKindAsEnum() == Attribute::NoBuiltin ||
         I->getKindAsEnum() == Attribute::Cold) {
       if (!isFunction)
@@ -877,6 +878,13 @@ void Verifier::visitFunction(Function &F) {
   // Check function attributes.
   VerifyFunctionAttrs(FT, Attrs, &F);
 
+  // On function declarations/definitions, we do not support the builtin
+  // attribute. We do not check this in VerifyFunctionAttrs since that is
+  // checking for Attributes that can/can not ever be on functions.
+  Assert1(!Attrs.hasAttribute(AttributeSet::FunctionIndex,
+                              Attribute::Builtin),
+          "Attribute 'builtin' can only be applied to a callsite.", &F);
+
   // Check that this function meets the restrictions on this calling convention.
   switch (F.getCallingConv()) {
   default:
@@ -1435,6 +1443,14 @@ void Verifier::VerifyCallSite(CallSite CS) {
               "Function has metadata parameter but isn't an intrinsic", I);
   }
 
+  // If the call site has the 'builtin' attribute, verify that it's applied to a
+  // direct call to a function with the 'nobuiltin' attribute.
+  if (CS.hasFnAttr(Attribute::Builtin))
+    Assert1(CS.getCalledFunction() &&
+            CS.getCalledFunction()->hasFnAttribute(Attribute::NoBuiltin),
+            "Attribute 'builtin' can only be used in a call to a function with "
+            "the 'nobuiltin' attribute.", I);
+
   visitInstruction(*I);
 }