1 // WebAssemblyMachineFunctionInfo.h-WebAssembly machine function info-*- C++ -*-
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 declares WebAssembly-specific per-machine-function
12 /// information.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYMACHINEFUNCTIONINFO_H
17 #define LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYMACHINEFUNCTIONINFO_H
18 
19 #include "WebAssemblyRegisterInfo.h"
20 #include "llvm/CodeGen/MachineFunction.h"
21 #include "llvm/CodeGen/MachineRegisterInfo.h"
22 
23 namespace llvm {
24 
25 /// This class is derived from MachineFunctionInfo and contains private
26 /// WebAssembly-specific information for each MachineFunction.
27 class WebAssemblyFunctionInfo final : public MachineFunctionInfo {
28   MachineFunction &MF;
29 
30   std::vector<MVT> Params;
31 
32   /// A mapping from CodeGen vreg index to WebAssembly register number.
33   std::vector<unsigned> WARegs;
34 
35   /// A mapping from CodeGen vreg index to a boolean value indicating whether
36   /// the given register is considered to be "stackified", meaning it has been
37   /// determined or made to meet the stack requirements:
38   ///   - single use (per path)
39   ///   - single def (per path)
40   ///   - defined and used in FIFO order with other stack registers
41   BitVector VRegStackified;
42 
43 public:
44   explicit WebAssemblyFunctionInfo(MachineFunction &MF) : MF(MF) {}
45   ~WebAssemblyFunctionInfo() override;
46 
47   void addParam(MVT VT) { Params.push_back(VT); }
48   const std::vector<MVT> &getParams() const { return Params; }
49 
50   static const unsigned UnusedReg = -1u;
51 
52   void stackifyVReg(unsigned VReg) {
53     if (TargetRegisterInfo::virtReg2Index(VReg) >= VRegStackified.size())
54       VRegStackified.resize(TargetRegisterInfo::virtReg2Index(VReg) + 1);
55     VRegStackified.set(TargetRegisterInfo::virtReg2Index(VReg));
56   }
57   bool isVRegStackified(unsigned VReg) const {
58     if (TargetRegisterInfo::virtReg2Index(VReg) >= VRegStackified.size())
59       return false;
60     return VRegStackified.test(TargetRegisterInfo::virtReg2Index(VReg));
61   }
62 
63   void initWARegs();
64   void setWAReg(unsigned VReg, unsigned WAReg) {
65     assert(WAReg != UnusedReg);
66     WARegs[TargetRegisterInfo::virtReg2Index(VReg)] = WAReg;
67   }
68   unsigned getWAReg(unsigned VReg) const {
69     return WARegs[TargetRegisterInfo::virtReg2Index(VReg)];
70   }
71 };
72 
73 } // end namespace llvm
74 
75 #endif
76