[DebugInfo][RemoveDIs] Switch some insertion routines to use iterators (#75330)

As part of RemoveDIs, we need instruction insertion to be done with
iterators rather than instruction pointers, so that we can communicate
some debug-info facts about the position. This patch is an entirely
mechanical replacement of Instruction * with BasicBlock::iterator, plus
using insertBefore to insert some instructions because we don't have
iterator-taking constructors yet.

Sadly it's not NFC because it causes dbg.value intrinsics / their
DPValue equivalents to shift location.

1 files changed, 14 insertions, 10 deletions

diff --git a/llvm/lib/CodeGen/CodeGenPrepare.cpp b/llvm/lib/CodeGen/CodeGenPrepare.cpp
index aa5cdd2..f9e791c 100644
--- a/llvm/lib/CodeGen/CodeGenPrepare.cpp
+++ b/llvm/lib/CodeGen/CodeGenPrepare.cpp
@@ -1384,7 +1384,8 @@ static bool SinkCast(CastInst *CI) {
       BasicBlock::iterator InsertPt = UserBB->getFirstInsertionPt();
       assert(InsertPt != UserBB->end());
       InsertedCast = CastInst::Create(CI->getOpcode(), CI->getOperand(0),
-                                      CI->getType(), "", &*InsertPt);
+                                      CI->getType(), "");
+      InsertedCast->insertBefore(*UserBB, InsertPt);
       InsertedCast->setDebugLoc(CI->getDebugLoc());
     }
 
@@ -2058,12 +2059,13 @@ SinkShiftAndTruncate(BinaryOperator *ShiftI, Instruction *User, ConstantInt *CI,
       assert(InsertPt != TruncUserBB->end());
       // Sink the shift
       if (ShiftI->getOpcode() == Instruction::AShr)
-        InsertedShift = BinaryOperator::CreateAShr(ShiftI->getOperand(0), CI,
-                                                   "", &*InsertPt);
+        InsertedShift =
+            BinaryOperator::CreateAShr(ShiftI->getOperand(0), CI, "");
       else
-        InsertedShift = BinaryOperator::CreateLShr(ShiftI->getOperand(0), CI,
-                                                   "", &*InsertPt);
+        InsertedShift =
+            BinaryOperator::CreateLShr(ShiftI->getOperand(0), CI, "");
       InsertedShift->setDebugLoc(ShiftI->getDebugLoc());
+      InsertedShift->insertBefore(*TruncUserBB, InsertPt);
 
       // Sink the trunc
       BasicBlock::iterator TruncInsertPt = TruncUserBB->getFirstInsertionPt();
@@ -2162,11 +2164,12 @@ static bool OptimizeExtractBits(BinaryOperator *ShiftI, ConstantInt *CI,
       assert(InsertPt != UserBB->end());
 
       if (ShiftI->getOpcode() == Instruction::AShr)
-        InsertedShift = BinaryOperator::CreateAShr(ShiftI->getOperand(0), CI,
-                                                   "", &*InsertPt);
+        InsertedShift =
+            BinaryOperator::CreateAShr(ShiftI->getOperand(0), CI, "");
       else
-        InsertedShift = BinaryOperator::CreateLShr(ShiftI->getOperand(0), CI,
-                                                   "", &*InsertPt);
+        InsertedShift =
+            BinaryOperator::CreateLShr(ShiftI->getOperand(0), CI, "");
+      InsertedShift->insertBefore(*UserBB, InsertPt);
       InsertedShift->setDebugLoc(ShiftI->getDebugLoc());
 
       MadeChange = true;
@@ -6628,7 +6631,8 @@ bool CodeGenPrepare::optimizeExtUses(Instruction *I) {
     if (!InsertedTrunc) {
       BasicBlock::iterator InsertPt = UserBB->getFirstInsertionPt();
       assert(InsertPt != UserBB->end());
-      InsertedTrunc = new TruncInst(I, Src->getType(), "", &*InsertPt);
+      InsertedTrunc = new TruncInst(I, Src->getType(), "");
+      InsertedTrunc->insertBefore(*UserBB, InsertPt);
       InsertedInsts.insert(InsertedTrunc);
     }