[Inliner] No longer honor nobuiltin attributes

llvm/include/llvm/Analysis/TargetLibraryInfo.h

@@ -324,21 +324,6 @@ class TargetLibraryInfo {
     return *this;
   }
 
-  /// Determine whether a callee with the given TLI can be inlined into
-  /// caller with this TLI, based on 'nobuiltin' attributes. When requested,
-  /// allow inlining into a caller with a superset of the callee's nobuiltin
-  /// attributes, which is conservatively correct.
-  bool areInlineCompatible(const TargetLibraryInfo &CalleeTLI,
-                           bool AllowCallerSuperset) const {
-    if (!AllowCallerSuperset)
-      return OverrideAsUnavailable == CalleeTLI.OverrideAsUnavailable;
-    BitVector B = OverrideAsUnavailable;
-    B |= CalleeTLI.OverrideAsUnavailable;
-    // We can inline if the union of the caller and callee's nobuiltin
-    // attributes is no stricter than the caller's nobuiltin attributes.
-    return B == OverrideAsUnavailable;
-  }
-
   /// Return true if the function type FTy is valid for the library function
   /// F, regardless of whether the function is available.
   bool isValidProtoForLibFunc(const FunctionType &FTy, LibFunc F,

llvm/lib/Analysis/InlineCost.cpp

@@ -164,11 +164,6 @@ static cl::opt<bool> OptComputeFullInlineCost(
     cl::desc("Compute the full inline cost of a call site even when the cost "
              "exceeds the threshold."));
 
-static cl::opt<bool> InlineCallerSupersetNoBuiltin(
-    "inline-caller-superset-nobuiltin", cl::Hidden, cl::init(true),
-    cl::desc("Allow inlining when caller has a superset of callee's nobuiltin "
-             "attributes."));
-
 static cl::opt<bool> DisableGEPConstOperand(
     "disable-gep-const-evaluation", cl::Hidden, cl::init(false),
     cl::desc("Disables evaluation of GetElementPtr with constant operands"));
@@ -2887,8 +2882,6 @@ static bool functionsHaveCompatibleAttributes(
   auto CalleeTLI = GetTLI(*Callee);
   return (IgnoreTTIInlineCompatible ||
           TTI.areInlineCompatible(Caller, Callee)) &&
-         GetTLI(*Caller).areInlineCompatible(CalleeTLI,
-                                             InlineCallerSupersetNoBuiltin) &&
          AttributeFuncs::areInlineCompatible(*Caller, *Callee);
 }