LLVM  10.0.0svn
XCoreFrameToArgsOffsetElim.cpp
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1 //===-- XCoreFrameToArgsOffsetElim.cpp ----------------------------*- C++ -*-=//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Replace Pseudo FRAME_TO_ARGS_OFFSET with the appropriate real offset.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "XCore.h"
14 #include "XCoreInstrInfo.h"
15 #include "XCoreSubtarget.h"
21 using namespace llvm;
22 
23 namespace {
24  struct XCoreFTAOElim : public MachineFunctionPass {
25  static char ID;
26  XCoreFTAOElim() : MachineFunctionPass(ID) {}
27 
28  bool runOnMachineFunction(MachineFunction &Fn) override;
29  MachineFunctionProperties getRequiredProperties() const override {
32  }
33 
34  StringRef getPassName() const override {
35  return "XCore FRAME_TO_ARGS_OFFSET Elimination";
36  }
37  };
38  char XCoreFTAOElim::ID = 0;
39 }
40 
41 /// createXCoreFrameToArgsOffsetEliminationPass - returns an instance of the
42 /// Frame to args offset elimination pass
44  return new XCoreFTAOElim();
45 }
46 
47 bool XCoreFTAOElim::runOnMachineFunction(MachineFunction &MF) {
48  const XCoreInstrInfo &TII =
49  *static_cast<const XCoreInstrInfo *>(MF.getSubtarget().getInstrInfo());
50  unsigned StackSize = MF.getFrameInfo().getStackSize();
51  for (MachineFunction::iterator MFI = MF.begin(), E = MF.end(); MFI != E;
52  ++MFI) {
53  MachineBasicBlock &MBB = *MFI;
54  for (MachineBasicBlock::iterator MBBI = MBB.begin(), EE = MBB.end();
55  MBBI != EE; ++MBBI) {
56  if (MBBI->getOpcode() == XCore::FRAME_TO_ARGS_OFFSET) {
57  MachineInstr &OldInst = *MBBI;
58  Register Reg = OldInst.getOperand(0).getReg();
59  MBBI = TII.loadImmediate(MBB, MBBI, Reg, StackSize);
60  OldInst.eraseFromParent();
61  }
62  }
63  }
64  return true;
65 }
This class represents lattice values for constants.
Definition: AllocatorList.h:23
unsigned Reg
MachineFunctionPass - This class adapts the FunctionPass interface to allow convenient creation of pa...
const HexagonInstrInfo * TII
void eraseFromParent()
Unlink &#39;this&#39; from the containing basic block and delete it.
FRAME_TO_ARGS_OFFSET - This node represents offset from frame pointer to first (possible) on-stack ar...
Definition: ISDOpcodes.h:90
virtual const TargetInstrInfo * getInstrInfo() const
FunctionPass * createXCoreFrameToArgsOffsetEliminationPass()
createXCoreFrameToArgsOffsetEliminationPass - returns an instance of the Frame to args offset elimina...
MachineBasicBlock::iterator loadImmediate(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, unsigned Reg, uint64_t Value) const
const TargetSubtargetInfo & getSubtarget() const
getSubtarget - Return the subtarget for which this machine code is being compiled.
MachineFrameInfo & getFrameInfo()
getFrameInfo - Return the frame info object for the current function.
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
FunctionPass class - This class is used to implement most global optimizations.
Definition: Pass.h:284
Iterator for intrusive lists based on ilist_node.
MachineFunctionProperties & set(Property P)
Representation of each machine instruction.
Definition: MachineInstr.h:63
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
Register getReg() const
getReg - Returns the register number.
const MachineOperand & getOperand(unsigned i) const
Definition: MachineInstr.h:415
uint64_t getStackSize() const
Return the number of bytes that must be allocated to hold all of the fixed size frame objects...
Properties which a MachineFunction may have at a given point in time.
Wrapper class representing virtual and physical registers.
Definition: Register.h:19