Rename invariant.group.barrier to launder.invariant.group

Summary:
This is one of the initial commit of "RFC: Devirtualization v2" proposal:
https://docs.google.com/document/d/16GVtCpzK8sIHNc2qZz6RN8amICNBtvjWUod2SujZVEo/edit?usp=sharing

Reviewers: rsmith, amharc, kuhar, sanjoy

Subscribers: arsenm, nhaehnle, javed.absar, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45111

llvm-svn: 331448
diff --git a/llvm/lib/IR/AutoUpgrade.cpp b/llvm/lib/IR/AutoUpgrade.cpp
index 13fb278..fd403f3 100644
--- a/llvm/lib/IR/AutoUpgrade.cpp
+++ b/llvm/lib/IR/AutoUpgrade.cpp
@@ -528,6 +528,17 @@
         return true;
       }
     }
+    if (Name.startswith("invariant.group.barrier")) {
+      // Rename invariant.group.barrier to launder.invariant.group
+      auto Args = F->getFunctionType()->params();
+      Type* ObjectPtr[1] = {Args[0]};
+      rename(F);
+      NewFn = Intrinsic::getDeclaration(F->getParent(),
+          Intrinsic::launder_invariant_group, ObjectPtr);
+      return true;
+
+    }
+
     break;
   }
   case 'm': {
diff --git a/llvm/lib/IR/Value.cpp b/llvm/lib/IR/Value.cpp
index a479d04..2f95e93 100644
--- a/llvm/lib/IR/Value.cpp
+++ b/llvm/lib/IR/Value.cpp
@@ -499,7 +499,7 @@
 enum PointerStripKind {
   PSK_ZeroIndices,
   PSK_ZeroIndicesAndAliases,
-  PSK_ZeroIndicesAndAliasesAndBarriers,
+  PSK_ZeroIndicesAndAliasesAndInvariantGroups,
   PSK_InBoundsConstantIndices,
   PSK_InBounds
 };
@@ -518,7 +518,7 @@
     if (auto *GEP = dyn_cast<GEPOperator>(V)) {
       switch (StripKind) {
       case PSK_ZeroIndicesAndAliases:
-      case PSK_ZeroIndicesAndAliasesAndBarriers:
+      case PSK_ZeroIndicesAndAliasesAndInvariantGroups:
       case PSK_ZeroIndices:
         if (!GEP->hasAllZeroIndices())
           return V;
@@ -546,11 +546,11 @@
           V = RV;
           continue;
         }
-        // The result of invariant.group.barrier must alias it's argument,
+        // The result of launder.invariant.group must alias it's argument,
         // but it can't be marked with returned attribute, that's why it needs
         // special case.
-        if (StripKind == PSK_ZeroIndicesAndAliasesAndBarriers &&
-            CS.getIntrinsicID() == Intrinsic::invariant_group_barrier) {
+        if (StripKind == PSK_ZeroIndicesAndAliasesAndInvariantGroups &&
+            CS.getIntrinsicID() == Intrinsic::launder_invariant_group) {
           V = CS.getArgOperand(0);
           continue;
         }
@@ -576,8 +576,8 @@
   return stripPointerCastsAndOffsets<PSK_InBoundsConstantIndices>(this);
 }
 
-const Value *Value::stripPointerCastsAndBarriers() const {
-  return stripPointerCastsAndOffsets<PSK_ZeroIndicesAndAliasesAndBarriers>(
+const Value *Value::stripPointerCastsAndInvariantGroups() const {
+  return stripPointerCastsAndOffsets<PSK_ZeroIndicesAndAliasesAndInvariantGroups>(
       this);
 }