Revert "[KeyInstr][Clang] For range stmt atoms" (#142630)

Reverts llvm/llvm-project#134647

Bot failure:

https://lab.llvm.org/buildbot/#/builders/144/builds/26730/steps/6/logs/FAIL__Clang__terminate-statements_cpp

Author: OCHyams

clang/lib/CodeGen/CGStmt.cpp

@@ -1483,14 +1483,7 @@ CodeGenFunction::EmitCXXForRangeStmt(const CXXForRangeStmt &S,
   if (!Weights && CGM.getCodeGenOpts().OptimizationLevel)
     BoolCondVal = emitCondLikelihoodViaExpectIntrinsic(
         BoolCondVal, Stmt::getLikelihood(S.getBody()));
-  auto *I = Builder.CreateCondBr(BoolCondVal, ForBody, ExitBlock, Weights);
-  // Key Instructions: Emit the condition and branch as separate atoms to
-  // match existing loop stepping behaviour. FIXME: We could have the branch as
-  // the backup location for the condition, which would probably be a better
-  // experience.
-  if (auto *CondI = dyn_cast<llvm::Instruction>(BoolCondVal))
-    addInstToNewSourceAtom(CondI, nullptr);
-  addInstToNewSourceAtom(I, nullptr);
+  Builder.CreateCondBr(BoolCondVal, ForBody, ExitBlock, Weights);
 
   if (ExitBlock != LoopExit.getBlock()) {
     EmitBlock(ExitBlock);
@@ -1516,10 +1509,6 @@ CodeGenFunction::EmitCXXForRangeStmt(const CXXForRangeStmt &S,
     EmitStmt(S.getBody());
   }
 
-  // The last block in the loop's body (which unconditionally branches to the
-  // `inc` block if there is one).
-  auto *FinalBodyBB = Builder.GetInsertBlock();
-
   EmitStopPoint(&S);
   // If there is an increment, emit it next.
   EmitBlock(Continue.getBlock());
@@ -1543,10 +1532,6 @@ CodeGenFunction::EmitCXXForRangeStmt(const CXXForRangeStmt &S,
 
   if (CGM.shouldEmitConvergenceTokens())
     ConvergenceTokenStack.pop_back();
-
-  // We want the for closing brace to be step-able on to match existing
-  // behaviour.
-  addInstToNewSourceAtom(FinalBodyBB->getTerminator(), nullptr);
 }
 
 void CodeGenFunction::EmitReturnOfRValue(RValue RV, QualType Ty) {