[globalisel] Add a combiner helpers for extending loads and use them in a pre-legalize combiner for AArch64
Summary: Depends on D45541
Reviewers: ab, aditya_nandakumar, bogner, rtereshin, volkan, rovka, javed.absar, aemerson
Subscribers: aemerson, rengolin, mgorny, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D45543
llvm-svn: 343521
diff --git a/llvm/lib/Target/AArch64/AArch64.h b/llvm/lib/Target/AArch64/AArch64.h
index edda13c..74f22e2 100644
--- a/llvm/lib/Target/AArch64/AArch64.h
+++ b/llvm/lib/Target/AArch64/AArch64.h
@@ -53,6 +53,7 @@
InstructionSelector *
createAArch64InstructionSelector(const AArch64TargetMachine &,
AArch64Subtarget &, AArch64RegisterBankInfo &);
+FunctionPass *createAArch64PreLegalizeCombiner();
void initializeAArch64A53Fix835769Pass(PassRegistry&);
void initializeAArch64A57FPLoadBalancingPass(PassRegistry&);
@@ -65,6 +66,7 @@
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
new file mode 100644
index 0000000..32487b9
--- /dev/null
+++ b/llvm/lib/Target/AArch64/AArch64PreLegalizerCombiner.cpp
@@ -0,0 +1,108 @@
+//=== 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 c4b9b45..a66f527 100644
--- a/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp
+++ b/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp
@@ -158,6 +158,7 @@
initializeAArch64ExpandPseudoPass(*PR);
initializeAArch64LoadStoreOptPass(*PR);
initializeAArch64SIMDInstrOptPass(*PR);
+ initializeAArch64PreLegalizerCombinerPass(*PR);
initializeAArch64PromoteConstantPass(*PR);
initializeAArch64RedundantCopyEliminationPass(*PR);
initializeAArch64StorePairSuppressPass(*PR);
@@ -348,6 +349,7 @@
bool addPreISel() override;
bool addInstSelector() override;
bool addIRTranslator() override;
+ void addPreLegalizeMachineIR() override;
bool addLegalizeMachineIR() override;
bool addRegBankSelect() override;
void addPreGlobalInstructionSelect() override;
@@ -449,6 +451,10 @@
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 d9a0051..e6ca69c 100644
--- a/llvm/lib/Target/AArch64/CMakeLists.txt
+++ b/llvm/lib/Target/AArch64/CMakeLists.txt
@@ -43,6 +43,7 @@
AArch64LoadStoreOptimizer.cpp
AArch64MacroFusion.cpp
AArch64MCInstLower.cpp
+ AArch64PreLegalizerCombiner.cpp
AArch64PromoteConstant.cpp
AArch64PBQPRegAlloc.cpp
AArch64RegisterBankInfo.cpp