lib/Transforms/Coroutines/CoroInternal.h

   1 //===- CoroInternal.h - Internal Coroutine interfaces ---------*- 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 // Common definitions/declarations used internally by coroutine lowering passes.
   9 //===----------------------------------------------------------------------===//
  10
  11 #ifndef LLVM_LIB_TRANSFORMS_COROUTINES_COROINTERNAL_H
  12 #define LLVM_LIB_TRANSFORMS_COROUTINES_COROINTERNAL_H
  13
  14 #include "CoroInstr.h"
  15 #include "llvm/Transforms/Coroutines.h"
  16
  17 namespace llvm {
  18
  19 class CallGraph;
  20 class CallGraphSCC;
  21 class PassRegistry;
  22
  23 void initializeCoroEarlyPass(PassRegistry &);
  24 void initializeCoroSplitPass(PassRegistry &);
  25 void initializeCoroElidePass(PassRegistry &);
  26 void initializeCoroCleanupPass(PassRegistry &);
  27
  28 // CoroEarly pass marks every function that has coro.begin with a string
  29 // attribute "coroutine.presplit"="0". CoroSplit pass processes the coroutine
  30 // twice. First, it lets it go through complete IPO optimization pipeline as a
  31 // single function. It forces restart of the pipeline by inserting an indirect
  32 // call to an empty function "coro.devirt.trigger" which is devirtualized by
  33 // CoroElide pass that triggers a restart of the pipeline by CGPassManager.
  34 // When CoroSplit pass sees the same coroutine the second time, it splits it up,
  35 // adds coroutine subfunctions to the SCC to be processed by IPO pipeline.
  36
  37 #define CORO_PRESPLIT_ATTR "coroutine.presplit"
  38 #define UNPREPARED_FOR_SPLIT "0"
  39 #define PREPARED_FOR_SPLIT "1"
  40
  41 #define CORO_DEVIRT_TRIGGER_FN "coro.devirt.trigger"
  42
  43 namespace coro {
  44
  45 bool declaresIntrinsics(Module &M, std::initializer_list<StringRef>);
  46 void replaceAllCoroAllocs(CoroBeginInst *CB, bool Replacement);
  47 void replaceAllCoroFrees(CoroBeginInst *CB, Value *Replacement);
  48 void replaceCoroFree(CoroIdInst *CoroId, bool Elide);
  49 void updateCallGraph(Function &Caller, ArrayRef<Function *> Funcs,
  50                      CallGraph &CG, CallGraphSCC &SCC);
  51
  52 // Keeps data and helper functions for lowering coroutine intrinsics.
  53 struct LowererBase {
  54   Module &TheModule;
  55   LLVMContext &Context;
  56   PointerType *const Int8Ptr;
  57   FunctionType *const ResumeFnType;
  58   ConstantPointerNull *const NullPtr;
  59
  60   LowererBase(Module &M);
  61   Value *makeSubFnCall(Value *Arg, int Index, Instruction *InsertPt);
  62 };
  63
  64 // Holds structural Coroutine Intrinsics for a particular function and other
  65 // values used during CoroSplit pass.
  66 struct LLVM_LIBRARY_VISIBILITY Shape {
  67   CoroBeginInst *CoroBegin;
  68   SmallVector<CoroEndInst *, 4> CoroEnds;
  69   SmallVector<CoroSizeInst *, 2> CoroSizes;
  70   SmallVector<CoroSuspendInst *, 4> CoroSuspends;
  71
  72   // Field Indexes for known coroutine frame fields.
  73   enum {
  74     ResumeField,
  75     DestroyField,
  76     PromiseField,
  77     IndexField,
  78   };
  79
  80   StructType *FrameTy;
  81   Instruction *FramePtr;
  82   BasicBlock *AllocaSpillBlock;
  83   SwitchInst *ResumeSwitch;
  84   AllocaInst *PromiseAlloca;
  85   bool HasFinalSuspend;
  86
  87   IntegerType *getIndexType() const {
  88     assert(FrameTy && "frame type not assigned");
  89     return cast<IntegerType>(FrameTy->getElementType(IndexField));
  90   }
  91   ConstantInt *getIndex(uint64_t Value) const {
  92     return ConstantInt::get(getIndexType(), Value);
  93   }
  94
  95   Shape() = default;
  96   explicit Shape(Function &F) { buildFrom(F); }
  97   void buildFrom(Function &F);
  98 };
  99
 100 void buildCoroutineFrame(Function &F, Shape &Shape);
 101
 102 } // End namespace coro.
 103 } // End namespace llvm
 104
 105 #endif