blob: 00b11321fdb204be56b533a48bdc57c8a99193f3 [file] [log] [blame]
//=- WebAssemblyMachineFunctionInfo.cpp - WebAssembly Machine Function Info -=//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This file implements WebAssembly-specific per-machine-function
/// information.
///
//===----------------------------------------------------------------------===//
#include "WebAssemblyMachineFunctionInfo.h"
#include "MCTargetDesc/WebAssemblyInstPrinter.h"
#include "Utils/WebAssemblyTypeUtilities.h"
#include "WebAssemblyISelLowering.h"
#include "WebAssemblySubtarget.h"
#include "llvm/CodeGen/Analysis.h"
#include "llvm/CodeGen/WasmEHFuncInfo.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;
WebAssemblyFunctionInfo::~WebAssemblyFunctionInfo() = default; // anchor.
void WebAssemblyFunctionInfo::initWARegs(MachineRegisterInfo &MRI) {
assert(WARegs.empty());
unsigned Reg = UnusedReg;
WARegs.resize(MRI.getNumVirtRegs(), Reg);
}
void llvm::computeLegalValueVTs(const Function &F, const TargetMachine &TM,
Type *Ty, SmallVectorImpl<MVT> &ValueVTs) {
const DataLayout &DL(F.getParent()->getDataLayout());
const WebAssemblyTargetLowering &TLI =
*TM.getSubtarget<WebAssemblySubtarget>(F).getTargetLowering();
SmallVector<EVT, 4> VTs;
ComputeValueVTs(TLI, DL, Ty, VTs);
for (EVT VT : VTs) {
unsigned NumRegs = TLI.getNumRegisters(F.getContext(), VT);
MVT RegisterVT = TLI.getRegisterType(F.getContext(), VT);
for (unsigned I = 0; I != NumRegs; ++I)
ValueVTs.push_back(RegisterVT);
}
}
void llvm::computeSignatureVTs(const FunctionType *Ty,
const Function *TargetFunc,
const Function &ContextFunc,
const TargetMachine &TM,
SmallVectorImpl<MVT> &Params,
SmallVectorImpl<MVT> &Results) {
computeLegalValueVTs(ContextFunc, TM, Ty->getReturnType(), Results);
MVT PtrVT = MVT::getIntegerVT(TM.createDataLayout().getPointerSizeInBits());
if (Results.size() > 1 &&
!TM.getSubtarget<WebAssemblySubtarget>(ContextFunc).hasMultivalue()) {
// WebAssembly can't lower returns of multiple values without demoting to
// sret unless multivalue is enabled (see
// WebAssemblyTargetLowering::CanLowerReturn). So replace multiple return
// values with a poitner parameter.
Results.clear();
Params.push_back(PtrVT);
}
for (auto *Param : Ty->params())
computeLegalValueVTs(ContextFunc, TM, Param, Params);
if (Ty->isVarArg())
Params.push_back(PtrVT);
// For swiftcc, emit additional swiftself and swifterror parameters
// if there aren't. These additional parameters are also passed for caller.
// They are necessary to match callee and caller signature for indirect
// call.
if (TargetFunc && TargetFunc->getCallingConv() == CallingConv::Swift) {
MVT PtrVT = MVT::getIntegerVT(TM.createDataLayout().getPointerSizeInBits());
bool HasSwiftErrorArg = false;
bool HasSwiftSelfArg = false;
for (const auto &Arg : TargetFunc->args()) {
HasSwiftErrorArg |= Arg.hasAttribute(Attribute::SwiftError);
HasSwiftSelfArg |= Arg.hasAttribute(Attribute::SwiftSelf);
}
if (!HasSwiftErrorArg)
Params.push_back(PtrVT);
if (!HasSwiftSelfArg)
Params.push_back(PtrVT);
}
}
void llvm::valTypesFromMVTs(const ArrayRef<MVT> &In,
SmallVectorImpl<wasm::ValType> &Out) {
for (MVT Ty : In)
Out.push_back(WebAssembly::toValType(Ty));
}
std::unique_ptr<wasm::WasmSignature>
llvm::signatureFromMVTs(const SmallVectorImpl<MVT> &Results,
const SmallVectorImpl<MVT> &Params) {
auto Sig = std::make_unique<wasm::WasmSignature>();
valTypesFromMVTs(Results, Sig->Returns);
valTypesFromMVTs(Params, Sig->Params);
return Sig;
}
yaml::WebAssemblyFunctionInfo::WebAssemblyFunctionInfo(
const llvm::WebAssemblyFunctionInfo &MFI)
: CFGStackified(MFI.isCFGStackified()) {
auto *EHInfo = MFI.getWasmEHFuncInfo();
const llvm::MachineFunction &MF = MFI.getMachineFunction();
for (auto VT : MFI.getParams())
Params.push_back(EVT(VT).getEVTString());
for (auto VT : MFI.getResults())
Results.push_back(EVT(VT).getEVTString());
// MFI.getWasmEHFuncInfo() is non-null only for functions with the
// personality function.
if (EHInfo) {
// SrcToUnwindDest can contain stale mappings in case BBs are removed in
// optimizations, in case, for example, they are unreachable. We should not
// include their info.
SmallPtrSet<const MachineBasicBlock *, 16> MBBs;
for (const auto &MBB : MF)
MBBs.insert(&MBB);
for (auto KV : EHInfo->SrcToUnwindDest) {
auto *SrcBB = KV.first.get<MachineBasicBlock *>();
auto *DestBB = KV.second.get<MachineBasicBlock *>();
if (MBBs.count(SrcBB) && MBBs.count(DestBB))
SrcToUnwindDest[SrcBB->getNumber()] = DestBB->getNumber();
}
}
}
void yaml::WebAssemblyFunctionInfo::mappingImpl(yaml::IO &YamlIO) {
MappingTraits<WebAssemblyFunctionInfo>::mapping(YamlIO, *this);
}
void WebAssemblyFunctionInfo::initializeBaseYamlFields(
const yaml::WebAssemblyFunctionInfo &YamlMFI) {
CFGStackified = YamlMFI.CFGStackified;
for (auto VT : YamlMFI.Params)
addParam(WebAssembly::parseMVT(VT.Value));
for (auto VT : YamlMFI.Results)
addResult(WebAssembly::parseMVT(VT.Value));
if (WasmEHInfo) {
for (auto KV : YamlMFI.SrcToUnwindDest)
WasmEHInfo->setUnwindDest(MF.getBlockNumbered(KV.first),
MF.getBlockNumbered(KV.second));
}
}