1 files changed, 83 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/GlobalISel/InstructionSelector.cpp b/llvm/lib/CodeGen/GlobalISel/InstructionSelector.cpp
new file mode 100644
index 000000000000..2ad35b3a72c9
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+++ b/llvm/lib/CodeGen/GlobalISel/InstructionSelector.cpp
@@ -0,0 +1,83 @@
+//===- llvm/CodeGen/GlobalISel/InstructionSelector.cpp --------------------===//
+//
+// 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
+/// This file implements the InstructionSelector class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
+#include "llvm/CodeGen/GlobalISel/Utils.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineOperand.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/TargetRegisterInfo.h"
+#include "llvm/MC/MCInstrDesc.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cassert>
+
+#define DEBUG_TYPE "instructionselector"
+
+using namespace llvm;
+
+InstructionSelector::MatcherState::MatcherState(unsigned MaxRenderers)
+    : Renderers(MaxRenderers), MIs() {}
+
+InstructionSelector::InstructionSelector() = default;
+
+bool InstructionSelector::constrainOperandRegToRegClass(
+    MachineInstr &I, unsigned OpIdx, const TargetRegisterClass &RC,
+    const TargetInstrInfo &TII, const TargetRegisterInfo &TRI,
+    const RegisterBankInfo &RBI) const {
+  MachineBasicBlock &MBB = *I.getParent();
+  MachineFunction &MF = *MBB.getParent();
+  MachineRegisterInfo &MRI = MF.getRegInfo();
+
+  return constrainOperandRegClass(MF, TRI, MRI, TII, RBI, I, RC,
+                                  I.getOperand(OpIdx), OpIdx);
+}
+
+bool InstructionSelector::isOperandImmEqual(
+    const MachineOperand &MO, int64_t Value,
+    const MachineRegisterInfo &MRI) const {
+  if (MO.isReg() && MO.getReg())
+    if (auto VRegVal = getConstantVRegValWithLookThrough(MO.getReg(), MRI))
+      return VRegVal->Value == Value;
+  return false;
+}
+
+bool InstructionSelector::isBaseWithConstantOffset(
+    const MachineOperand &Root, const MachineRegisterInfo &MRI) const {
+  if (!Root.isReg())
+    return false;
+
+  MachineInstr *RootI = MRI.getVRegDef(Root.getReg());
+  if (RootI->getOpcode() != TargetOpcode::G_GEP)
+    return false;
+
+  MachineOperand &RHS = RootI->getOperand(2);
+  MachineInstr *RHSI = MRI.getVRegDef(RHS.getReg());
+  if (RHSI->getOpcode() != TargetOpcode::G_CONSTANT)
+    return false;
+
+  return true;
+}
+
+bool InstructionSelector::isObviouslySafeToFold(MachineInstr &MI,
+                                                MachineInstr &IntoMI) const {
+  // Immediate neighbours are already folded.
+  if (MI.getParent() == IntoMI.getParent() &&
+      std::next(MI.getIterator()) == IntoMI.getIterator())
+    return true;
+
+  return !MI.mayLoadOrStore() && !MI.mayRaiseFPException() &&
+         !MI.hasUnmodeledSideEffects() && empty(MI.implicit_operands());
+}