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

2 files changed, 33 insertions, 2 deletions

diff --git a/include/llvm/IR/Attributes.h b/include/llvm/IR/Attributes.h
index 0d14709..0bf59cf 100644
--- a/include/llvm/IR/Attributes.h
+++ b/include/llvm/IR/Attributes.h
@@ -67,6 +67,8 @@ public:
                            ///< stored as log2 of alignment with +1 bias
                            ///< 0 means unaligned (different from align(1))
     AlwaysInline,          ///< inline=always
+    Builtin,               ///< Callee is recognized as a builtin, despite
+                           ///< nobuiltin attribute on its declaration.
     ByVal,                 ///< Pass structure by value
     Cold,                  ///< Marks function as being in a cold path.
     InlineHint,            ///< Source said inlining was desirable
diff --git a/include/llvm/IR/Instructions.h b/include/llvm/IR/Instructions.h
index 3a8738f..e05c3a8 100644
--- a/include/llvm/IR/Instructions.h
+++ b/include/llvm/IR/Instructions.h
@@ -1278,7 +1278,11 @@ public:
   void removeAttribute(unsigned i, Attribute attr);
 
   /// \brief Determine whether this call has the given attribute.
-  bool hasFnAttr(Attribute::AttrKind A) const;
+  bool hasFnAttr(Attribute::AttrKind A) const {
+    assert(A != Attribute::NoBuiltin &&
+           "Use CallInst::isNoBuiltin() to check for Attribute::NoBuiltin");
+    return hasFnAttrImpl(A);
+  }
 
   /// \brief Determine whether the call or the callee has the given attributes.
   bool paramHasAttr(unsigned i, Attribute::AttrKind A) const;
@@ -1288,6 +1292,13 @@ public:
     return AttributeList.getParamAlignment(i);
   }
 
+  /// \brief Return true if the call should not be treated as a call to a
+  /// builtin.
+  bool isNoBuiltin() const {
+    return hasFnAttrImpl(Attribute::NoBuiltin) &&
+      !hasFnAttrImpl(Attribute::Builtin);
+  }
+
   /// \brief Return true if the call should not be inlined.
   bool isNoInline() const { return hasFnAttr(Attribute::NoInline); }
   void setIsNoInline() {
@@ -1378,6 +1389,9 @@ public:
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 private:
+
+  bool hasFnAttrImpl(Attribute::AttrKind A) const;
+
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   void setInstructionSubclassData(unsigned short D) {
@@ -3021,7 +3035,11 @@ public:
   void removeAttribute(unsigned i, Attribute attr);
 
   /// \brief Determine whether this call has the NoAlias attribute.
-  bool hasFnAttr(Attribute::AttrKind A) const;
+  bool hasFnAttr(Attribute::AttrKind A) const {
+    assert(A != Attribute::NoBuiltin &&
+           "Use CallInst::isNoBuiltin() to check for Attribute::NoBuiltin");
+    return hasFnAttrImpl(A);
+  }
 
   /// \brief Determine whether the call or the callee has the given attributes.
   bool paramHasAttr(unsigned i, Attribute::AttrKind A) const;
@@ -3031,6 +3049,15 @@ public:
     return AttributeList.getParamAlignment(i);
   }
 
+  /// \brief Return true if the call should not be treated as a call to a
+  /// builtin.
+  bool isNoBuiltin() const {
+    // We assert in hasFnAttr if one passes in Attribute::NoBuiltin, so we have
+    // to check it by hand.
+    return hasFnAttrImpl(Attribute::NoBuiltin) &&
+      !hasFnAttrImpl(Attribute::Builtin);
+  }
+
   /// \brief Return true if the call should not be inlined.
   bool isNoInline() const { return hasFnAttr(Attribute::NoInline); }
   void setIsNoInline() {
@@ -3137,6 +3164,8 @@ private:
   virtual unsigned getNumSuccessorsV() const;
   virtual void setSuccessorV(unsigned idx, BasicBlock *B);
 
+  bool hasFnAttrImpl(Attribute::AttrKind A) const;
+
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   void setInstructionSubclassData(unsigned short D) {