llvm-project/llvm/lib/Target/WebAssembly/WebAssemblyTargetTransformInfo.h
Chuanqi Xu 0b5ead6590 [WebAssembly] Don't set musttail for coroutines when tail-call is not
enabled

The C++20 Coroutines couldn't be compiled to WebAssembly due to an
optimization named symmetric transfer requires the support for musttail
calls but WebAssembly doesn't support it yet.

This patch tries to fix the problem by adding a supportsTailCalls
method to TargetTransformImpl to skip the symmetric transfer when
tail-call feature is not supported.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D128794
2022-06-30 11:15:40 +08:00

84 lines
2.9 KiB
C++

//==- WebAssemblyTargetTransformInfo.h - WebAssembly-specific TTI -*- C++ -*-=//
//
// 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 a TargetTransformInfo::Concept conforming object specific
/// to the WebAssembly target machine.
///
/// It uses the target's detailed information to provide more precise answers to
/// certain TTI queries, while letting the target independent and default TTI
/// implementations handle the rest.
///
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYTARGETTRANSFORMINFO_H
#define LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYTARGETTRANSFORMINFO_H
#include "WebAssemblyTargetMachine.h"
#include "llvm/CodeGen/BasicTTIImpl.h"
#include <algorithm>
namespace llvm {
class WebAssemblyTTIImpl final : public BasicTTIImplBase<WebAssemblyTTIImpl> {
typedef BasicTTIImplBase<WebAssemblyTTIImpl> BaseT;
typedef TargetTransformInfo TTI;
friend BaseT;
const WebAssemblySubtarget *ST;
const WebAssemblyTargetLowering *TLI;
const WebAssemblySubtarget *getST() const { return ST; }
const WebAssemblyTargetLowering *getTLI() const { return TLI; }
public:
WebAssemblyTTIImpl(const WebAssemblyTargetMachine *TM, const Function &F)
: BaseT(TM, F.getParent()->getDataLayout()), ST(TM->getSubtargetImpl(F)),
TLI(ST->getTargetLowering()) {}
/// \name Scalar TTI Implementations
/// @{
// TODO: Implement more Scalar TTI for WebAssembly
TTI::PopcntSupportKind getPopcntSupport(unsigned TyWidth) const;
void getUnrollingPreferences(Loop *L, ScalarEvolution &SE,
TTI::UnrollingPreferences &UP,
OptimizationRemarkEmitter *ORE) const;
/// @}
/// \name Vector TTI Implementations
/// @{
unsigned getNumberOfRegisters(unsigned ClassID) const;
TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const;
InstructionCost getArithmeticInstrCost(
unsigned Opcode, Type *Ty, TTI::TargetCostKind CostKind,
TTI::OperandValueKind Opd1Info = TTI::OK_AnyValue,
TTI::OperandValueKind Opd2Info = TTI::OK_AnyValue,
TTI::OperandValueProperties Opd1PropInfo = TTI::OP_None,
TTI::OperandValueProperties Opd2PropInfo = TTI::OP_None,
ArrayRef<const Value *> Args = ArrayRef<const Value *>(),
const Instruction *CxtI = nullptr);
InstructionCost getVectorInstrCost(unsigned Opcode, Type *Val,
unsigned Index);
/// @}
bool areInlineCompatible(const Function *Caller,
const Function *Callee) const;
bool supportsTailCalls() const;
};
} // end namespace llvm
#endif