1// WebAssemblyMachineFunctionInfo.h-WebAssembly machine function info-*- 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/// \file
10/// This file declares WebAssembly-specific per-machine-function
11/// information.
12///
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYMACHINEFUNCTIONINFO_H
16#define LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYMACHINEFUNCTIONINFO_H
17
18#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
19#include "llvm/CodeGen/MIRYamlMapping.h"
20#include "llvm/CodeGen/MachineRegisterInfo.h"
21#include "llvm/MC/MCSymbolWasm.h"
22
23namespace llvm {
24class WebAssemblyTargetLowering;
25
26struct WasmEHFuncInfo;
27
28namespace yaml {
29struct WebAssemblyFunctionInfo;
30}
31
32/// This class is derived from MachineFunctionInfo and contains private
33/// WebAssembly-specific information for each MachineFunction.
34class WebAssemblyFunctionInfo final : public MachineFunctionInfo {
35 std::vector<MVT> Params;
36 std::vector<MVT> Results;
37 std::vector<MVT> Locals;
38
39 /// A mapping from CodeGen vreg index to WebAssembly register number.
40 std::vector<unsigned> WARegs;
41
42 /// A mapping from CodeGen vreg index to a boolean value indicating whether
43 /// the given register is considered to be "stackified", meaning it has been
44 /// determined or made to meet the stack requirements:
45 /// - single use (per path)
46 /// - single def (per path)
47 /// - defined and used in LIFO order with other stack registers
48 BitVector VRegStackified;
49
50 // A virtual register holding the pointer to the vararg buffer for vararg
51 // functions. It is created and set in TLI::LowerFormalArguments and read by
52 // TLI::LowerVASTART
53 unsigned VarargVreg = -1U;
54
55 // A virtual register holding the base pointer for functions that have
56 // overaligned values on the user stack.
57 unsigned BasePtrVreg = -1U;
58 // A virtual register holding the frame base. This is either FP or SP
59 // after it has been replaced by a vreg
60 unsigned FrameBaseVreg = -1U;
61 // The local holding the frame base. This is either FP or SP
62 // after WebAssemblyExplicitLocals
63 unsigned FrameBaseLocal = -1U;
64
65 // Function properties.
66 bool CFGStackified = false;
67
68public:
69 explicit WebAssemblyFunctionInfo(const Function &F,
70 const TargetSubtargetInfo *STI) {}
71 ~WebAssemblyFunctionInfo() override;
72
73 MachineFunctionInfo *
74 clone(BumpPtrAllocator &Allocator, MachineFunction &DestMF,
75 const DenseMap<MachineBasicBlock *, MachineBasicBlock *> &Src2DstMBB)
76 const override;
77
78 void initializeBaseYamlFields(MachineFunction &MF,
79 const yaml::WebAssemblyFunctionInfo &YamlMFI);
80
81 void addParam(MVT VT) { Params.push_back(x: VT); }
82 const std::vector<MVT> &getParams() const { return Params; }
83
84 void addResult(MVT VT) { Results.push_back(x: VT); }
85 const std::vector<MVT> &getResults() const { return Results; }
86
87 void clearParamsAndResults() {
88 Params.clear();
89 Results.clear();
90 }
91
92 void setNumLocals(size_t NumLocals) { Locals.resize(new_size: NumLocals, x: MVT::i32); }
93 void setLocal(size_t i, MVT VT) { Locals[i] = VT; }
94 void addLocal(MVT VT) { Locals.push_back(x: VT); }
95 const std::vector<MVT> &getLocals() const { return Locals; }
96
97 unsigned getVarargBufferVreg() const {
98 assert(VarargVreg != -1U && "Vararg vreg hasn't been set");
99 return VarargVreg;
100 }
101 void setVarargBufferVreg(unsigned Reg) { VarargVreg = Reg; }
102
103 unsigned getBasePointerVreg() const {
104 assert(BasePtrVreg != -1U && "Base ptr vreg hasn't been set");
105 return BasePtrVreg;
106 }
107 void setFrameBaseVreg(unsigned Reg) { FrameBaseVreg = Reg; }
108 unsigned getFrameBaseVreg() const {
109 assert(FrameBaseVreg != -1U && "Frame base vreg hasn't been set");
110 return FrameBaseVreg;
111 }
112 void clearFrameBaseVreg() { FrameBaseVreg = -1U; }
113 // Return true if the frame base physreg has been replaced by a virtual reg.
114 bool isFrameBaseVirtual() const { return FrameBaseVreg != -1U; }
115 void setFrameBaseLocal(unsigned Local) { FrameBaseLocal = Local; }
116 unsigned getFrameBaseLocal() const {
117 assert(FrameBaseLocal != -1U && "Frame base local hasn't been set");
118 return FrameBaseLocal;
119 }
120 void setBasePointerVreg(unsigned Reg) { BasePtrVreg = Reg; }
121
122 void stackifyVReg(MachineRegisterInfo &MRI, Register VReg) {
123 assert(MRI.getUniqueVRegDef(VReg));
124 auto I = VReg.virtRegIndex();
125 if (I >= VRegStackified.size())
126 VRegStackified.resize(N: I + 1);
127 VRegStackified.set(I);
128 }
129 void unstackifyVReg(Register VReg) {
130 auto I = VReg.virtRegIndex();
131 if (I < VRegStackified.size())
132 VRegStackified.reset(Idx: I);
133 }
134 bool isVRegStackified(Register VReg) const {
135 auto I = VReg.virtRegIndex();
136 if (I >= VRegStackified.size())
137 return false;
138 return VRegStackified.test(Idx: I);
139 }
140
141 void initWARegs(MachineRegisterInfo &MRI);
142 void setWAReg(Register VReg, unsigned WAReg) {
143 assert(WAReg != WebAssembly::UnusedReg);
144 auto I = VReg.virtRegIndex();
145 assert(I < WARegs.size());
146 WARegs[I] = WAReg;
147 }
148 unsigned getWAReg(Register VReg) const {
149 auto I = VReg.virtRegIndex();
150 assert(I < WARegs.size());
151 return WARegs[I];
152 }
153
154 bool isCFGStackified() const { return CFGStackified; }
155 void setCFGStackified(bool Value = true) { CFGStackified = Value; }
156};
157
158void computeLegalValueVTs(const WebAssemblyTargetLowering &TLI,
159 LLVMContext &Ctx, const DataLayout &DL, Type *Ty,
160 SmallVectorImpl<MVT> &ValueVTs);
161
162void computeLegalValueVTs(const Function &F, const TargetMachine &TM, Type *Ty,
163 SmallVectorImpl<MVT> &ValueVTs);
164
165// Compute the signature for a given FunctionType (Ty). Note that it's not the
166// signature for ContextFunc (ContextFunc is just used to get varous context)
167void computeSignatureVTs(const FunctionType *Ty, const Function *TargetFunc,
168 const Function &ContextFunc, const TargetMachine &TM,
169 SmallVectorImpl<MVT> &Params,
170 SmallVectorImpl<MVT> &Results);
171
172void valTypesFromMVTs(ArrayRef<MVT> In, SmallVectorImpl<wasm::ValType> &Out);
173
174wasm::WasmSignature *signatureFromMVTs(MCContext &Ctx,
175 const SmallVectorImpl<MVT> &Results,
176 const SmallVectorImpl<MVT> &Params);
177
178namespace yaml {
179
180using BBNumberMap = DenseMap<int, int>;
181
182struct WebAssemblyFunctionInfo final : public yaml::MachineFunctionInfo {
183 std::vector<FlowStringValue> Params;
184 std::vector<FlowStringValue> Results;
185 bool CFGStackified = false;
186 // The same as WasmEHFuncInfo's SrcToUnwindDest, but stored in the mapping of
187 // BB numbers
188 BBNumberMap SrcToUnwindDest;
189
190 WebAssemblyFunctionInfo() = default;
191 WebAssemblyFunctionInfo(const llvm::MachineFunction &MF,
192 const llvm::WebAssemblyFunctionInfo &MFI);
193
194 void mappingImpl(yaml::IO &YamlIO) override;
195 ~WebAssemblyFunctionInfo() = default;
196};
197
198template <> struct MappingTraits<WebAssemblyFunctionInfo> {
199 static void mapping(IO &YamlIO, WebAssemblyFunctionInfo &MFI) {
200 YamlIO.mapOptional(Key: "params", Val&: MFI.Params, Default: std::vector<FlowStringValue>());
201 YamlIO.mapOptional(Key: "results", Val&: MFI.Results, Default: std::vector<FlowStringValue>());
202 YamlIO.mapOptional(Key: "isCFGStackified", Val&: MFI.CFGStackified, Default: false);
203 YamlIO.mapOptional(Key: "wasmEHFuncInfo", Val&: MFI.SrcToUnwindDest);
204 }
205};
206
207template <> struct CustomMappingTraits<BBNumberMap> {
208 static void inputOne(IO &YamlIO, StringRef Key,
209 BBNumberMap &SrcToUnwindDest) {
210 YamlIO.mapRequired(Key: Key.str().c_str(),
211 Val&: SrcToUnwindDest[std::atoi(nptr: Key.str().c_str())]);
212 }
213
214 static void output(IO &YamlIO, BBNumberMap &SrcToUnwindDest) {
215 for (auto KV : SrcToUnwindDest)
216 YamlIO.mapRequired(Key: std::to_string(val: KV.first).c_str(), Val&: KV.second);
217 }
218};
219
220} // end namespace yaml
221
222} // end namespace llvm
223
224#endif
225