[NFC][RemoveDIs] Bulk update utilities to insert with iterators

As part of the RemoveDIs project we need LLVM to insert instructions using
iterators wherever possible, so that the iterators can carry a bit of
debug-info. This commit implements some of that by updating the contents of
llvm/lib/Transforms/Utils to always use iterator-versions of instruction
constructors.

There are two general flavours of update:
 * Almost all call-sites just call getIterator on an instruction
 * Several make use of an existing iterator (scenarios where the code is
   actually significant for debug-info)
The underlying logic is that any call to getFirstInsertionPt or similar
APIs that identify the start of a block need to have that iterator passed
directly to the insertion function, without being converted to a bare
Instruction pointer along the way.

I've also switched DemotePHIToStack to take an optional iterator: it needs
to take an iterator, and having a no-insert-location behaviour appears to
be important. The constructors for ICmpInst and FCmpInst have been updated
too. They're the only instructions that take block _references_ rather than
pointers for certain calls, and a future patch is going to make use of
default-null block insertion locations.

All of this should be NFC.

1 files changed, 4 insertions, 4 deletions

diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 5bb109a..5aa59ac 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -1297,7 +1297,7 @@ static void UpdatePHINodes(BasicBlock *OrigBB, BasicBlock *NewBB,
     // PHI.
     // Create the new PHI node, insert it into NewBB at the end of the block
     PHINode *NewPHI =
-        PHINode::Create(PN->getType(), Preds.size(), PN->getName() + ".ph", BI);
+        PHINode::Create(PN->getType(), Preds.size(), PN->getName() + ".ph", BI->getIterator());
 
     // NOTE! This loop walks backwards for a reason! First off, this minimizes
     // the cost of removal if we end up removing a large number of values, and
@@ -1517,7 +1517,7 @@ static void SplitLandingPadPredecessorsImpl(
       assert(!LPad->getType()->isTokenTy() &&
              "Split cannot be applied if LPad is token type. Otherwise an "
              "invalid PHINode of token type would be created.");
-      PHINode *PN = PHINode::Create(LPad->getType(), 2, "lpad.phi", LPad);
+      PHINode *PN = PHINode::Create(LPad->getType(), 2, "lpad.phi", LPad->getIterator());
       PN->addIncoming(Clone1, NewBB1);
       PN->addIncoming(Clone2, NewBB2);
       LPad->replaceAllUsesWith(PN);
@@ -1904,7 +1904,7 @@ static void reconnectPhis(BasicBlock *Out, BasicBlock *GuardBlock,
     auto Phi = cast<PHINode>(I);
     auto NewPhi =
         PHINode::Create(Phi->getType(), Incoming.size(),
-                        Phi->getName() + ".moved", &FirstGuardBlock->front());
+                        Phi->getName() + ".moved", FirstGuardBlock->begin());
     for (auto *In : Incoming) {
       Value *V = UndefValue::get(Phi->getType());
       if (In == Out) {
@@ -2023,7 +2023,7 @@ static void calcPredicateUsingInteger(
       Value *Id1 = ConstantInt::get(Type::getInt32Ty(Context),
                                     std::distance(Outgoing.begin(), Succ1Iter));
       IncomingId = SelectInst::Create(Condition, Id0, Id1, "target.bb.idx",
-                                      In->getTerminator());
+                                      In->getTerminator()->getIterator());
     } else {
       // Get the index of the non-null successor.
       auto SuccIter = Succ0 ? find(Outgoing, Succ0) : find(Outgoing, Succ1);