1 //=- WebAssemblyMachineFunctionInfo.cpp - WebAssembly Machine Function Info -=// 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 implements WebAssembly-specific per-machine-function 11 /// information. 12 /// 13 //===----------------------------------------------------------------------===// 14 15 #include "WebAssemblyMachineFunctionInfo.h" 16 #include "WebAssemblyISelLowering.h" 17 #include "WebAssemblySubtarget.h" 18 #include "llvm/CodeGen/Analysis.h" 19 using namespace llvm; 20 21 WebAssemblyFunctionInfo::~WebAssemblyFunctionInfo() = default; // anchor. 22 23 void WebAssemblyFunctionInfo::initWARegs() { 24 assert(WARegs.empty()); 25 unsigned Reg = UnusedReg; 26 WARegs.resize(MF.getRegInfo().getNumVirtRegs(), Reg); 27 } 28 29 void llvm::computeLegalValueVTs(const Function &F, const TargetMachine &TM, 30 Type *Ty, SmallVectorImpl<MVT> &ValueVTs) { 31 const DataLayout &DL(F.getParent()->getDataLayout()); 32 const WebAssemblyTargetLowering &TLI = 33 *TM.getSubtarget<WebAssemblySubtarget>(F).getTargetLowering(); 34 SmallVector<EVT, 4> VTs; 35 ComputeValueVTs(TLI, DL, Ty, VTs); 36 37 for (EVT VT : VTs) { 38 unsigned NumRegs = TLI.getNumRegisters(F.getContext(), VT); 39 MVT RegisterVT = TLI.getRegisterType(F.getContext(), VT); 40 for (unsigned I = 0; I != NumRegs; ++I) 41 ValueVTs.push_back(RegisterVT); 42 } 43 } 44 45 void llvm::computeSignatureVTs(const FunctionType *Ty, const Function &F, 46 const TargetMachine &TM, 47 SmallVectorImpl<MVT> &Params, 48 SmallVectorImpl<MVT> &Results) { 49 computeLegalValueVTs(F, TM, Ty->getReturnType(), Results); 50 51 MVT PtrVT = MVT::getIntegerVT(TM.createDataLayout().getPointerSizeInBits()); 52 if (Results.size() > 1 && 53 !TM.getSubtarget<WebAssemblySubtarget>(F).hasMultivalue()) { 54 // WebAssembly can't lower returns of multiple values without demoting to 55 // sret unless multivalue is enabled (see 56 // WebAssemblyTargetLowering::CanLowerReturn). So replace multiple return 57 // values with a poitner parameter. 58 Results.clear(); 59 Params.push_back(PtrVT); 60 } 61 62 for (auto *Param : Ty->params()) 63 computeLegalValueVTs(F, TM, Param, Params); 64 if (Ty->isVarArg()) 65 Params.push_back(PtrVT); 66 } 67 68 void llvm::valTypesFromMVTs(const ArrayRef<MVT> &In, 69 SmallVectorImpl<wasm::ValType> &Out) { 70 for (MVT Ty : In) 71 Out.push_back(WebAssembly::toValType(Ty)); 72 } 73 74 std::unique_ptr<wasm::WasmSignature> 75 llvm::signatureFromMVTs(const SmallVectorImpl<MVT> &Results, 76 const SmallVectorImpl<MVT> &Params) { 77 auto Sig = std::make_unique<wasm::WasmSignature>(); 78 valTypesFromMVTs(Results, Sig->Returns); 79 valTypesFromMVTs(Params, Sig->Params); 80 return Sig; 81 } 82 83 yaml::WebAssemblyFunctionInfo::WebAssemblyFunctionInfo( 84 const llvm::WebAssemblyFunctionInfo &MFI) 85 : CFGStackified(MFI.isCFGStackified()) {} 86 87 void yaml::WebAssemblyFunctionInfo::mappingImpl(yaml::IO &YamlIO) { 88 MappingTraits<WebAssemblyFunctionInfo>::mapping(YamlIO, *this); 89 } 90 91 void WebAssemblyFunctionInfo::initializeBaseYamlFields( 92 const yaml::WebAssemblyFunctionInfo &YamlMFI) { 93 CFGStackified = YamlMFI.CFGStackified; 94 } 95