[RewriteStatepointsForGC] Adjust naming scheme to be more stable

The names for instructions inserted were previous dependent on iteration order.  By deriving the names from the original instructions, we can avoid instability in tests without resorting to ordered traversals.  It also makes the IR mildly easier to read at large scale.

llvm-svn: 243140

1 files changed, 7 insertions, 3 deletions

diff --git a/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp b/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp
index 5a1fac0c456..aa30cfb8ff9 100644
--- a/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp
+++ b/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp
@@ -858,13 +858,17 @@ static Value *findBasePointer(Value *I, DefiningValueMapTy &cache) {
         BasicBlock *BB = I->getParent();
         int NumPreds = std::distance(pred_begin(BB), pred_end(BB));
         assert(NumPreds > 0 && "how did we reach here");
-        return PHINode::Create(I->getType(), NumPreds, "base_phi", I);
+        std::string Name = I->hasName() ?
+           (I->getName() + ".base").str() : "base_phi";
+        return PHINode::Create(I->getType(), NumPreds, Name, I);
       }
       SelectInst *Sel = cast<SelectInst>(I);
       // The undef will be replaced later
       UndefValue *Undef = UndefValue::get(Sel->getType());
+      std::string Name = I->hasName() ?
+         (I->getName() + ".base").str() : "base_select";
       return SelectInst::Create(Sel->getCondition(), Undef,
-                                Undef, "base_select", Sel);
+                                Undef, Name, Sel);
     };
     Instruction *BaseInst = MakeBaseInstPlaceholder(I);
     // Add metadata marking this as a base value
@@ -1283,7 +1287,7 @@ makeStatepointExplicitImpl(const CallSite &CS, /* to replace */
     // original block.
     InvokeInst *invoke = InvokeInst::Create(
         gc_statepoint_decl, toReplace->getNormalDest(),
-        toReplace->getUnwindDest(), args, "", toReplace->getParent());
+        toReplace->getUnwindDest(), args, "statepoint_token", toReplace->getParent());
     invoke->setCallingConv(toReplace->getCallingConv());
 
     // Currently we will fail on parameter attributes and on certain