diff options
Diffstat (limited to 'lib/CodeGen/GlobalISel/InstructionSelector.cpp')
-rw-r--r-- | lib/CodeGen/GlobalISel/InstructionSelector.cpp | 34 |
1 files changed, 28 insertions, 6 deletions
diff --git a/lib/CodeGen/GlobalISel/InstructionSelector.cpp b/lib/CodeGen/GlobalISel/InstructionSelector.cpp index bf427225d6a9..88669bd68c00 100644 --- a/lib/CodeGen/GlobalISel/InstructionSelector.cpp +++ b/lib/CodeGen/GlobalISel/InstructionSelector.cpp @@ -6,8 +6,10 @@ // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// +// /// \file /// This file implements the InstructionSelector class. +// //===----------------------------------------------------------------------===// #include "llvm/CodeGen/GlobalISel/InstructionSelector.h" @@ -16,14 +18,11 @@ #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineInstr.h" #include "llvm/CodeGen/MachineOperand.h" -#include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineRegisterInfo.h" +#include "llvm/CodeGen/TargetRegisterInfo.h" #include "llvm/MC/MCInstrDesc.h" -#include "llvm/IR/Constants.h" -#include "llvm/Target/TargetInstrInfo.h" #include "llvm/Support/Debug.h" #include "llvm/Support/raw_ostream.h" -#include "llvm/Target/TargetRegisterInfo.h" #include <cassert> #define DEBUG_TYPE "instructionselector" @@ -31,7 +30,7 @@ using namespace llvm; InstructionSelector::MatcherState::MatcherState(unsigned MaxRenderers) - : Renderers(MaxRenderers, nullptr), MIs() {} + : Renderers(MaxRenderers), MIs() {} InstructionSelector::InstructionSelector() = default; @@ -100,7 +99,30 @@ bool InstructionSelector::isOperandImmEqual( return false; } -bool InstructionSelector::isObviouslySafeToFold(MachineInstr &MI) const { +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.hasUnmodeledSideEffects() && MI.implicit_operands().begin() == MI.implicit_operands().end(); } |