xref: /llvm-project/llvm/include/llvm/Transforms/Utils/LowerAtomic.h (revision 30dd1297fa2cc172ef7a1435775010d7efd673fd)
1 //===- LowerAtomic.h - Lower atomic intrinsics ------------------*- 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 /// \file
9 // This pass lowers atomic intrinsics to non-atomic form for use in a known
10 // non-preemptible environment.
11 ///
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_TRANSFORMS_UTILS_LOWERATOMIC_H
15 #define LLVM_TRANSFORMS_UTILS_LOWERATOMIC_H
16 
17 #include "llvm/IR/Instructions.h"
18 
19 namespace llvm {
20 
21 class IRBuilderBase;
22 
23 /// Convert the given Cmpxchg into primitive load and compare.
24 bool lowerAtomicCmpXchgInst(AtomicCmpXchgInst *CXI);
25 
26 /// Emit IR to implement the given cmpxchg operation on values in registers,
27 /// returning the new value.
28 std::pair<Value *, Value *> buildCmpXchgValue(IRBuilderBase &Builder,
29                                               Value *Ptr, Value *Cmp,
30                                               Value *Val, Align Alignment);
31 
32 /// Convert the given RMWI into primitive load and stores,
33 /// assuming that doing so is legal. Return true if the lowering
34 /// succeeds.
35 bool lowerAtomicRMWInst(AtomicRMWInst *RMWI);
36 
37 /// Emit IR to implement the given atomicrmw operation on values in registers,
38 /// returning the new value.
39 Value *buildAtomicRMWValue(AtomicRMWInst::BinOp Op, IRBuilderBase &Builder,
40                            Value *Loaded, Value *Val);
41 }
42 
43 #endif // LLVM_TRANSFORMS_UTILS_LOWERATOMIC_H
44