Revert: r343521 and r343541: [globalisel] Add a combiner helpers for extending loads and use them in a pre-legalize combiner for AArch64

There's a strange assertion on two of the Green Dragon bots that goes away when
this is reverted. The assertion is in RegBankAlloc and if it is this commit then
-verify-machine-instrs should have caught it earlier in the pipeline.

llvm-svn: 343546

4 files changed, 0 insertions, 117 deletions

diff --git a/llvm/lib/Target/AArch64/AArch64.h b/llvm/lib/Target/AArch64/AArch64.h
index 74f22e287f8..edda13ce97e 100644
--- a/llvm/lib/Target/AArch64/AArch64.h
+++ b/llvm/lib/Target/AArch64/AArch64.h
@@ -53,7 +53,6 @@ FunctionPass *createAArch64CollectLOHPass();
 InstructionSelector *
 createAArch64InstructionSelector(const AArch64TargetMachine &,
                                  AArch64Subtarget &, AArch64RegisterBankInfo &);
-FunctionPass *createAArch64PreLegalizeCombiner();
 
 void initializeAArch64A53Fix835769Pass(PassRegistry&);
 void initializeAArch64A57FPLoadBalancingPass(PassRegistry&);
@@ -66,7 +65,6 @@ void initializeAArch64DeadRegisterDefinitionsPass(PassRegistry&);
 void initializeAArch64ExpandPseudoPass(PassRegistry&);
 void initializeAArch64LoadStoreOptPass(PassRegistry&);
 void initializeAArch64SIMDInstrOptPass(PassRegistry&);
-void initializeAArch64PreLegalizerCombinerPass(PassRegistry&);
 void initializeAArch64PromoteConstantPass(PassRegistry&);
 void initializeAArch64RedundantCopyEliminationPass(PassRegistry&);
 void initializeAArch64StorePairSuppressPass(PassRegistry&);
diff --git a/llvm/lib/Target/AArch64/AArch64PreLegalizerCombiner.cpp b/llvm/lib/Target/AArch64/AArch64PreLegalizerCombiner.cpp
deleted file mode 100644
index 32487b9ccc3..00000000000
--- a/llvm/lib/Target/AArch64/AArch64PreLegalizerCombiner.cpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//=== lib/CodeGen/GlobalISel/AArch64PreLegalizerCombiner.cpp --------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This pass does combining of machine instructions at the generic MI level,
-// before the legalizer.
-//
-//===----------------------------------------------------------------------===//
-
-#include "AArch64TargetMachine.h"
-#include "llvm/CodeGen/GlobalISel/Combiner.h"
-#include "llvm/CodeGen/GlobalISel/CombinerHelper.h"
-#include "llvm/CodeGen/GlobalISel/CombinerInfo.h"
-#include "llvm/CodeGen/GlobalISel/MIPatternMatch.h"
-#include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/CodeGen/TargetPassConfig.h"
-#include "llvm/Support/Debug.h"
-
-#define DEBUG_TYPE "aarch64-prelegalizer-combiner"
-
-using namespace llvm;
-using namespace MIPatternMatch;
-
-namespace {
-class AArch64PreLegalizerCombinerInfo : public CombinerInfo {
-public:
-  AArch64PreLegalizerCombinerInfo()
-      : CombinerInfo(/*AllowIllegalOps*/ true, /*ShouldLegalizeIllegal*/ false,
-                     /*LegalizerInfo*/ nullptr) {}
-  virtual bool combine(CombinerChangeObserver &Observer, MachineInstr &MI,
-                       MachineIRBuilder &B) const override;
-};
-
-bool AArch64PreLegalizerCombinerInfo::combine(CombinerChangeObserver &Observer,
-                                              MachineInstr &MI,
-                                              MachineIRBuilder &B) const {
-  CombinerHelper Helper(Observer, B);
-
-  switch (MI.getOpcode()) {
-  default:
-    return false;
-  case TargetOpcode::G_LOAD:
-  case TargetOpcode::G_SEXTLOAD:
-  case TargetOpcode::G_ZEXTLOAD:
-    return Helper.tryCombineExtendingLoads(MI);
-  }
-
-  return false;
-}
-
-// Pass boilerplate
-// ================
-
-class AArch64PreLegalizerCombiner : public MachineFunctionPass {
-public:
-  static char ID;
-
-  AArch64PreLegalizerCombiner();
-
-  StringRef getPassName() const override { return "AArch64PreLegalizerCombiner"; }
-
-  bool runOnMachineFunction(MachineFunction &MF) override;
-
-  void getAnalysisUsage(AnalysisUsage &AU) const override;
-};
-}
-
-void AArch64PreLegalizerCombiner::getAnalysisUsage(AnalysisUsage &AU) const {
-  AU.addRequired<TargetPassConfig>();
-  AU.setPreservesCFG();
-  getSelectionDAGFallbackAnalysisUsage(AU);
-  MachineFunctionPass::getAnalysisUsage(AU);
-}
-
-AArch64PreLegalizerCombiner::AArch64PreLegalizerCombiner() : MachineFunctionPass(ID) {
-  initializeAArch64PreLegalizerCombinerPass(*PassRegistry::getPassRegistry());
-}
-
-bool AArch64PreLegalizerCombiner::runOnMachineFunction(MachineFunction &MF) {
-  if (MF.getProperties().hasProperty(
-          MachineFunctionProperties::Property::FailedISel))
-    return false;
-  auto *TPC = &getAnalysis<TargetPassConfig>();
-  AArch64PreLegalizerCombinerInfo PCInfo;
-  Combiner C(PCInfo, TPC);
-  return C.combineMachineInstrs(MF);
-}
-
-char AArch64PreLegalizerCombiner::ID = 0;
-INITIALIZE_PASS_BEGIN(AArch64PreLegalizerCombiner, DEBUG_TYPE,
-                      "Combine AArch64 machine instrs before legalization",
-                      false, false)
-INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
-INITIALIZE_PASS_END(AArch64PreLegalizerCombiner, DEBUG_TYPE,
-                    "Combine AArch64 machine instrs before legalization", false,
-                    false)
-
-
-namespace llvm {
-FunctionPass *createAArch64PreLegalizeCombiner() {
-  return new AArch64PreLegalizerCombiner();
-}
-} // end namespace llvm
diff --git a/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp b/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp
index a66f5277f24..c4b9b45f67b 100644
--- a/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp
+++ b/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp
@@ -158,7 +158,6 @@ extern "C" void LLVMInitializeAArch64Target() {
   initializeAArch64ExpandPseudoPass(*PR);
   initializeAArch64LoadStoreOptPass(*PR);
   initializeAArch64SIMDInstrOptPass(*PR);
-  initializeAArch64PreLegalizerCombinerPass(*PR);
   initializeAArch64PromoteConstantPass(*PR);
   initializeAArch64RedundantCopyEliminationPass(*PR);
   initializeAArch64StorePairSuppressPass(*PR);
@@ -349,7 +348,6 @@ public:
   bool addPreISel() override;
   bool addInstSelector() override;
   bool addIRTranslator() override;
-  void addPreLegalizeMachineIR() override;
   bool addLegalizeMachineIR() override;
   bool addRegBankSelect() override;
   void addPreGlobalInstructionSelect() override;
@@ -451,10 +449,6 @@ bool AArch64PassConfig::addIRTranslator() {
   return false;
 }
 
-void AArch64PassConfig::addPreLegalizeMachineIR() {
-  addPass(createAArch64PreLegalizeCombiner());
-}
-
 bool AArch64PassConfig::addLegalizeMachineIR() {
   addPass(new Legalizer());
   return false;
diff --git a/llvm/lib/Target/AArch64/CMakeLists.txt b/llvm/lib/Target/AArch64/CMakeLists.txt
index e6ca69c1971..d9a00512f71 100644
--- a/llvm/lib/Target/AArch64/CMakeLists.txt
+++ b/llvm/lib/Target/AArch64/CMakeLists.txt
@@ -43,7 +43,6 @@ add_llvm_target(AArch64CodeGen
   AArch64LoadStoreOptimizer.cpp
   AArch64MacroFusion.cpp
   AArch64MCInstLower.cpp
-  AArch64PreLegalizerCombiner.cpp
   AArch64PromoteConstant.cpp
   AArch64PBQPRegAlloc.cpp
   AArch64RegisterBankInfo.cpp