Clean up strange uses of getAnalysisIfAvailable (#65729)

After a pass calls addRequired<X>() it is strange to call
getAnalysisIfAvailable<X>() because analysis X should always be
available. Use getAnalysis<X>() instead.

Author: jayfoad

llvm/lib/CodeGen/EarlyIfConversion.cpp

@@ -1092,7 +1092,7 @@ bool EarlyIfConverter::runOnMachineFunction(MachineFunction &MF) {
   SchedModel = STI.getSchedModel();
   MRI = &MF.getRegInfo();
   DomTree = &getAnalysis<MachineDominatorTree>();
-  Loops = getAnalysisIfAvailable<MachineLoopInfo>();
+  Loops = &getAnalysis<MachineLoopInfo>();
   Traces = &getAnalysis<MachineTraceMetrics>();
   MinInstr = nullptr;
 
@@ -1226,7 +1226,7 @@ bool EarlyIfPredicator::runOnMachineFunction(MachineFunction &MF) {
   MRI = &MF.getRegInfo();
   SchedModel.init(&STI);
   DomTree = &getAnalysis<MachineDominatorTree>();
-  Loops = getAnalysisIfAvailable<MachineLoopInfo>();
+  Loops = &getAnalysis<MachineLoopInfo>();
   MBPI = &getAnalysis<MachineBranchProbabilityInfo>();
 
   bool Changed = false;

llvm/lib/CodeGen/TypePromotion.cpp

@@ -1016,11 +1016,8 @@ bool TypePromotionLegacy::runOnFunction(Function &F) {
   if (skipFunction(F))
     return false;
 
-  auto *TPC = getAnalysisIfAvailable<TargetPassConfig>();
-  if (!TPC)
-    return false;
-
-  auto *TM = &TPC->getTM<TargetMachine>();
+  auto &TPC = getAnalysis<TargetPassConfig>();
+  auto *TM = &TPC.getTM<TargetMachine>();
   auto &TTI = getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
   auto &LI = getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
 

llvm/lib/CodeGen/VirtRegMap.cpp

@@ -261,7 +261,7 @@ bool VirtRegRewriter::runOnMachineFunction(MachineFunction &fn) {
   Indexes = &getAnalysis<SlotIndexes>();
   LIS = &getAnalysis<LiveIntervals>();
   VRM = &getAnalysis<VirtRegMap>();
-  DebugVars = getAnalysisIfAvailable<LiveDebugVariables>();
+  DebugVars = &getAnalysis<LiveDebugVariables>();
   LLVM_DEBUG(dbgs() << "********** REWRITE VIRTUAL REGISTERS **********\n"
                     << "********** Function: " << MF->getName() << '\n');
   LLVM_DEBUG(VRM->dump());

llvm/lib/Target/AArch64/AArch64ConditionalCompares.cpp

@@ -935,7 +935,7 @@ bool AArch64ConditionalCompares::runOnMachineFunction(MachineFunction &MF) {
   SchedModel = MF.getSubtarget().getSchedModel();
   MRI = &MF.getRegInfo();
   DomTree = &getAnalysis<MachineDominatorTree>();
-  Loops = getAnalysisIfAvailable<MachineLoopInfo>();
+  Loops = &getAnalysis<MachineLoopInfo>();
   MBPI = &getAnalysis<MachineBranchProbabilityInfo>();
   Traces = &getAnalysis<MachineTraceMetrics>();
   MinInstr = nullptr;

llvm/lib/Transforms/Scalar/GVN.cpp

@@ -3286,7 +3286,7 @@ class llvm::gvn::GVNLegacyPass : public FunctionPass {
     if (skipFunction(F))
       return false;
 
-    auto *LIWP = getAnalysisIfAvailable<LoopInfoWrapperPass>();
+    auto &LIWP = getAnalysis<LoopInfoWrapperPass>();
 
     auto *MSSAWP = getAnalysisIfAvailable<MemorySSAWrapperPass>();
     return Impl.runImpl(
@@ -3297,7 +3297,7 @@ class llvm::gvn::GVNLegacyPass : public FunctionPass {
         Impl.isMemDepEnabled()
             ? &getAnalysis<MemoryDependenceWrapperPass>().getMemDep()
             : nullptr,
-        LIWP ? &LIWP->getLoopInfo() : nullptr,
+        &LIWP.getLoopInfo(),
         &getAnalysis<OptimizationRemarkEmitterWrapperPass>().getORE(),
         MSSAWP ? &MSSAWP->getMSSA() : nullptr);
   }