lib/Target/WebAssembly/WebAssemblyFastISel.cpp

//===-- WebAssemblyFastISel.cpp - WebAssembly FastISel implementation -----===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// \brief This file defines the WebAssembly-specific support for the FastISel
/// class. Some of the target-specific code is generated by tablegen in the file
/// WebAssemblyGenFastISel.inc, which is #included here.
///
//===----------------------------------------------------------------------===//

#include "WebAssembly.h"
#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
#include "WebAssemblySubtarget.h"
#include "WebAssemblyTargetMachine.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/CodeGen/FastISel.h"
#include "llvm/CodeGen/FunctionLoweringInfo.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Operator.h"
using namespace llvm;

#define DEBUG_TYPE "wasm-fastisel"

namespace {

class WebAssemblyFastISel final : public FastISel {
  /// Keep a pointer to the WebAssemblySubtarget around so that we can make the
  /// right decision when generating code for different targets.
  const WebAssemblySubtarget *Subtarget;
  LLVMContext *Context;

  // Call handling routines.
private:
public:
  // Backend specific FastISel code.
  WebAssemblyFastISel(FunctionLoweringInfo &FuncInfo,
                      const TargetLibraryInfo *LibInfo)
      : FastISel(FuncInfo, LibInfo, /*SkipTargetIndependentISel=*/true) {
    Subtarget = &FuncInfo.MF->getSubtarget<WebAssemblySubtarget>();
    Context = &FuncInfo.Fn->getContext();
  }

  bool fastSelectInstruction(const Instruction *I) override;

#include "WebAssemblyGenFastISel.inc"
};

} // end anonymous namespace

bool WebAssemblyFastISel::fastSelectInstruction(const Instruction *I) {
  switch (I->getOpcode()) {
  default:
    break;
    // TODO: add fast-isel selection cases here...
  }

  // Fall back to target-independent instruction selection.
  return selectOperator(I, I->getOpcode());
}

FastISel *WebAssembly::createFastISel(FunctionLoweringInfo &FuncInfo,
                                      const TargetLibraryInfo *LibInfo) {
  return new WebAssemblyFastISel(FuncInfo, LibInfo);
}