[llvm] [X86][GISEL] Enable PostLegalize Combiner (PR #174696)

[Evgenii Kudriashov via llvm-commits]

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@@ -0,0 +1,189 @@
+//=== X86PostLegalizerCombiner.cpp --------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Post-legalization combines on generic MachineInstrs.
+///
+/// The combines here must preserve instruction legality.
+///
+/// Lowering combines (e.g. pseudo matching) should be handled by
+/// X86PostLegalizerLowering.
+///
+/// Combines which don't rely on instruction legality should go in the
+/// X86PreLegalizerCombiner.
+///
+//===----------------------------------------------------------------------===//
+#include "X86.h"
+#include "X86TargetMachine.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/CodeGen/GlobalISel/CSEInfo.h"
+#include "llvm/CodeGen/GlobalISel/CSEMIRBuilder.h"
+#include "llvm/CodeGen/GlobalISel/Combiner.h"
+#include "llvm/CodeGen/GlobalISel/CombinerHelper.h"
+#include "llvm/CodeGen/GlobalISel/CombinerInfo.h"
+#include "llvm/CodeGen/GlobalISel/GIMatchTableExecutorImpl.h"
+#include "llvm/CodeGen/GlobalISel/GISelChangeObserver.h"
+#include "llvm/CodeGen/GlobalISel/GISelValueTracking.h"
+#include "llvm/CodeGen/GlobalISel/GenericMachineInstrs.h"
+#include "llvm/CodeGen/GlobalISel/MIPatternMatch.h"
+#include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
+#include "llvm/CodeGen/GlobalISel/Utils.h"
+#include "llvm/CodeGen/MachineDominators.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/TargetOpcodes.h"
+#include "llvm/CodeGen/TargetPassConfig.h"
+#include "llvm/Support/Debug.h"
+
+#define GET_GICOMBINER_DEPS
+#include "X86GenPostLegalizeGICombiner.inc"
+#undef GET_GICOMBINER_DEPS
+
+#define DEBUG_TYPE "X86-postlegalizer-combiner"
+
+using namespace llvm;
+using namespace MIPatternMatch;
+
+namespace {
+
+#define GET_GICOMBINER_TYPES
+#include "X86GenPostLegalizeGICombiner.inc"
+#undef GET_GICOMBINER_TYPES
+
+class X86PostLegalizerCombinerImpl : public Combiner {
+protected:
+  const CombinerHelper Helper;
+  const X86PostLegalizerCombinerImplRuleConfig &RuleConfig;
+  const X86Subtarget &STI;
+
+public:
+  X86PostLegalizerCombinerImpl(
+      MachineFunction &MF, CombinerInfo &CInfo, const TargetPassConfig *TPC,
+      GISelValueTracking &VT, GISelCSEInfo *CSEInfo,
+      const X86PostLegalizerCombinerImplRuleConfig &RuleConfig,
+      const X86Subtarget &STI, MachineDominatorTree *MDT,
+      const LegalizerInfo *LI);
+
+  static const char *getName() { return "X86PostLegalizerCombiner"; }
+
+  bool tryCombineAll(MachineInstr &I) const override;
+  bool tryCombineAllImpl(MachineInstr &I) const;
+
+private:
+#define GET_GICOMBINER_CLASS_MEMBERS
+#include "X86GenPostLegalizeGICombiner.inc"
+#undef GET_GICOMBINER_CLASS_MEMBERS
+};
+
+#define GET_GICOMBINER_IMPL
+#include "X86GenPostLegalizeGICombiner.inc"
+#undef GET_GICOMBINER_IMPL
+
+X86PostLegalizerCombinerImpl::X86PostLegalizerCombinerImpl(
+    MachineFunction &MF, CombinerInfo &CInfo, const TargetPassConfig *TPC,
+    GISelValueTracking &VT, GISelCSEInfo *CSEInfo,
+    const X86PostLegalizerCombinerImplRuleConfig &RuleConfig,
+    const X86Subtarget &STI, MachineDominatorTree *MDT, const LegalizerInfo *LI)
+    : Combiner(MF, CInfo, TPC, &VT, CSEInfo),
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e-kud wrote:

Probably it could be a part of the class declaration since it has empty body, but it is more a matter of taste.

https://github.com/llvm/llvm-project/pull/174696