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

llvm-svn: 365336

2 files changed, 3 insertions, 0 deletions

diff --git a/llvm/lib/IR/Attributes.cpp b/llvm/lib/IR/Attributes.cpp
index 99fc447c5af..0073eda0838 100644
--- a/llvm/lib/IR/Attributes.cpp
+++ b/llvm/lib/IR/Attributes.cpp
@@ -321,6 +321,8 @@ std::string Attribute::getAsString(bool InAttrGrp) const {
     return "nocapture";
   if (hasAttribute(Attribute::NoDuplicate))
     return "noduplicate";
+  if (hasAttribute(Attribute::NoFree))
+    return "nofree";
   if (hasAttribute(Attribute::NoImplicitFloat))
     return "noimplicitfloat";
   if (hasAttribute(Attribute::NoInline))
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index b0464346557..2655e3ce81e 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -1497,6 +1497,7 @@ static bool isFuncOnlyAttr(Attribute::AttrKind Kind) {
   case Attribute::NoCfCheck:
   case Attribute::NoUnwind:
   case Attribute::NoInline:
+  case Attribute::NoFree:
   case Attribute::AlwaysInline:
   case Attribute::OptimizeForSize:
   case Attribute::StackProtect: