Add, and infer, a nofree function attribute

This patch adds a function attribute, nofree, to indicate that a function does
not, directly or indirectly, call a memory-deallocation function (e.g., free,
C++'s operator delete).

Reviewers: jdoerfert

Differential Revision: https://reviews.llvm.org/D49165


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365336 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Bitcode/Writer/BitcodeWriter.cpp

@@ -639,6 +639,8 @@ static uint64_t getAttrKindEncoding(Attribute::AttrKind Kind) {
     return bitc::ATTR_KIND_NO_CAPTURE;
   case Attribute::NoDuplicate:
     return bitc::ATTR_KIND_NO_DUPLICATE;
+  case Attribute::NoFree:
+    return bitc::ATTR_KIND_NOFREE;
   case Attribute::NoImplicitFloat:
     return bitc::ATTR_KIND_NO_IMPLICIT_FLOAT;
   case Attribute::NoInline: