Revert "IR: MDNode => Value"

Instead, we're going to separate metadata from the Value hierarchy.  See
PR21532.

This reverts commit r221375.
This reverts commit r221373.
This reverts commit r221359.
This reverts commit r221167.
This reverts commit r221027.
This reverts commit r221024.
This reverts commit r221023.
This reverts commit r220995.
This reverts commit r220994.

llvm-svn: 221711
diff --git a/llvm/lib/IR/Instructions.cpp b/llvm/lib/IR/Instructions.cpp
index 6aaea75..4b48d7d 100644
--- a/llvm/lib/IR/Instructions.cpp
+++ b/llvm/lib/IR/Instructions.cpp
@@ -791,7 +791,7 @@
 
   // Update profile metadata if present and it matches our structural
   // expectations.
-  MDNode *ProfileData = getMDNode(LLVMContext::MD_prof);
+  MDNode *ProfileData = getMetadata(LLVMContext::MD_prof);
   if (!ProfileData || ProfileData->getNumOperands() != 3)
     return;
 
@@ -2072,7 +2072,8 @@
 /// An accuracy of 0.0 means that the operation should be performed with the
 /// default precision.
 float FPMathOperator::getFPAccuracy() const {
-  const MDNode *MD = cast<Instruction>(this)->getMDNode(LLVMContext::MD_fpmath);
+  const MDNode *MD =
+      cast<Instruction>(this)->getMetadata(LLVMContext::MD_fpmath);
   if (!MD)
     return 0.0;
   ConstantFP *Accuracy = cast<ConstantFP>(MD->getOperand(0));