1 //===-- WebAssemblyRegisterInfo.cpp - WebAssembly Register Information ----===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 ///
10 /// \file
11 /// \brief This file contains the WebAssembly implementation of the
12 /// TargetRegisterInfo class.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #include "WebAssemblyRegisterInfo.h"
17 #include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
18 #include "WebAssemblyFrameLowering.h"
19 #include "WebAssemblyInstrInfo.h"
20 #include "WebAssemblyMachineFunctionInfo.h"
21 #include "WebAssemblySubtarget.h"
22 #include "llvm/CodeGen/MachineFrameInfo.h"
23 #include "llvm/CodeGen/MachineInstrBuilder.h"
24 #include "llvm/CodeGen/MachineRegisterInfo.h"
25 #include "llvm/IR/Function.h"
26 #include "llvm/Support/raw_ostream.h"
27 #include "llvm/Target/TargetFrameLowering.h"
28 #include "llvm/Target/TargetOptions.h"
29 using namespace llvm;
30 
31 #define DEBUG_TYPE "wasm-reg-info"
32 
33 #define GET_REGINFO_TARGET_DESC
34 #include "WebAssemblyGenRegisterInfo.inc"
35 
36 WebAssemblyRegisterInfo::WebAssemblyRegisterInfo(const Triple &TT)
37     : WebAssemblyGenRegisterInfo(0), TT(TT) {}
38 
39 const MCPhysReg *
40 WebAssemblyRegisterInfo::getCalleeSavedRegs(const MachineFunction *) const {
41   static const MCPhysReg CalleeSavedRegs[] = {0};
42   return CalleeSavedRegs;
43 }
44 
45 BitVector
46 WebAssemblyRegisterInfo::getReservedRegs(const MachineFunction & /*MF*/) const {
47   BitVector Reserved(getNumRegs());
48   for (auto Reg : {WebAssembly::SP32, WebAssembly::SP64, WebAssembly::FP32,
49                    WebAssembly::FP64})
50     Reserved.set(Reg);
51   return Reserved;
52 }
53 
54 void WebAssemblyRegisterInfo::eliminateFrameIndex(
55     MachineBasicBlock::iterator /*II*/, int /*SPAdj*/,
56     unsigned /*FIOperandNum*/, RegScavenger * /*RS*/) const {
57   llvm_unreachable(
58       "TODO: implement WebAssemblyRegisterInfo::eliminateFrameIndex");
59 }
60 
61 unsigned
62 WebAssemblyRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
63   static const unsigned Regs[2][2] = {
64       /*            !isArch64Bit       isArch64Bit      */
65       /* !hasFP */ {WebAssembly::SP32, WebAssembly::SP64},
66       /*  hasFP */ {WebAssembly::FP32, WebAssembly::FP64}};
67   const WebAssemblyFrameLowering *TFI = getFrameLowering(MF);
68   return Regs[TFI->hasFP(MF)][TT.isArch64Bit()];
69 }
70 
71 const TargetRegisterClass *
72 WebAssemblyRegisterInfo::getPointerRegClass(const MachineFunction &MF,
73                                             unsigned Kind) const {
74   assert(Kind == 0 && "Only one kind of pointer on WebAssembly");
75   if (MF.getSubtarget<WebAssemblySubtarget>().hasAddr64())
76     return &WebAssembly::I64RegClass;
77   return &WebAssembly::I32RegClass;
78 }
79