llvm/llvm/lib/Transforms/Coroutines/Coroutines.cpp

//===- Coroutines.cpp -----------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// This file implements the common infrastructure for Coroutine Passes.
//
//===----------------------------------------------------------------------===//

#include "CoroInstr.h"
#include "CoroInternal.h"
#include "CoroShape.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Analysis/CallGraph.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/InstIterator.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Transforms/Utils/Local.h"
#include <cassert>
#include <cstddef>
#include <utility>

usingnamespacellvm;

// Construct the lowerer base class and initialize its members.
coro::LowererBase::LowererBase(Module &M)
    : … { … }

// Creates a call to llvm.coro.subfn.addr to obtain a resume function address.
// It generates the following:
//
//    call ptr @llvm.coro.subfn.addr(ptr %Arg, i8 %index)

CallInst *coro::LowererBase::makeSubFnCall(Value *Arg, int Index,
                                           Instruction *InsertPt) { … }

// NOTE: Must be sorted!
static const char *const CoroIntrinsics[] = …;

#ifndef NDEBUG
static bool isCoroutineIntrinsicName(StringRef Name) {
  return Intrinsic::lookupLLVMIntrinsicByName(CoroIntrinsics, Name) != -1;
}
#endif

bool coro::isSuspendBlock(BasicBlock *BB) { … }

bool coro::declaresAnyIntrinsic(const Module &M) { … }

// Verifies if a module has named values listed. Also, in debug mode verifies
// that names are intrinsic names.
bool coro::declaresIntrinsics(const Module &M,
                              const std::initializer_list<StringRef> List) { … }

// Replace all coro.frees associated with the provided CoroId either with 'null'
// if Elide is true and with its frame parameter otherwise.
void coro::replaceCoroFree(CoroIdInst *CoroId, bool Elide) { … }

void coro::suppressCoroAllocs(CoroIdInst *CoroId) { … }

// Replacing llvm.coro.alloc with false will suppress dynamic
// allocation as it is expected for the frontend to generate the code that
// looks like:
//   id = coro.id(...)
//   mem = coro.alloc(id) ? malloc(coro.size()) : 0;
//   coro.begin(id, mem)
void coro::suppressCoroAllocs(LLVMContext &Context,
                              ArrayRef<CoroAllocInst *> CoroAllocs) { … }

static void clear(coro::Shape &Shape) { … }

static CoroSaveInst *createCoroSave(CoroBeginInst *CoroBegin,
                                    CoroSuspendInst *SuspendInst) { … }

// Collect "interesting" coroutine intrinsics.
void coro::Shape::buildFrom(Function &F) { … }

static void propagateCallAttrsFromCallee(CallInst *Call, Function *Callee) { … }

static void addCallToCallGraph(CallGraph *CG, CallInst *Call, Function *Callee){ … }

Value *coro::Shape::emitAlloc(IRBuilder<> &Builder, Value *Size,
                              CallGraph *CG) const { … }

void coro::Shape::emitDealloc(IRBuilder<> &Builder, Value *Ptr,
                              CallGraph *CG) const { … }

[[noreturn]] static void fail(const Instruction *I, const char *Reason,
                              Value *V) { … }

/// Check that the given value is a well-formed prototype for the
/// llvm.coro.id.retcon.* intrinsics.
static void checkWFRetconPrototype(const AnyCoroIdRetconInst *I, Value *V) { … }

/// Check that the given value is a well-formed allocator.
static void checkWFAlloc(const Instruction *I, Value *V) { … }

/// Check that the given value is a well-formed deallocator.
static void checkWFDealloc(const Instruction *I, Value *V) { … }

static void checkConstantInt(const Instruction *I, Value *V,
                             const char *Reason) { … }

void AnyCoroIdRetconInst::checkWellFormed() const { … }

static void checkAsyncFuncPointer(const Instruction *I, Value *V) { … }

void CoroIdAsyncInst::checkWellFormed() const { … }

static void checkAsyncContextProjectFunction(const Instruction *I,
                                             Function *F) { … }

void CoroSuspendAsyncInst::checkWellFormed() const { … }

void CoroAsyncEndInst::checkWellFormed() const { … }