1//===-- GuardUtils.h - Utils for work with guards ---------------*- 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// Utils that are used to perform transformations related to guards and their
9// conditions.
10//===----------------------------------------------------------------------===//
11
12#ifndef LLVM_TRANSFORMS_UTILS_GUARDUTILS_H
13#define LLVM_TRANSFORMS_UTILS_GUARDUTILS_H
14
15namespace llvm {
16
17class BranchInst;
18class CallInst;
19class Function;
20class Value;
21
22/// Splits control flow at point of \p Guard, replacing it with explicit branch
23/// by the condition of guard's first argument. The taken branch then goes to
24/// the block that contains \p Guard's successors, and the non-taken branch
25/// goes to a newly-created deopt block that contains a sole call of the
26/// deoptimize function \p DeoptIntrinsic. If 'UseWC' is set, preserve the
27/// widenable nature of the guard by lowering to equivelent form. If not set,
28/// lower to a form without widenable semantics.
29void makeGuardControlFlowExplicit(Function *DeoptIntrinsic, CallInst *Guard,
30 bool UseWC);
31
32/// Given a branch we know is widenable (defined per Analysis/GuardUtils.h),
33/// widen it such that condition 'NewCond' is also known to hold on the taken
34/// path. Branch remains widenable after transform.
35void widenWidenableBranch(BranchInst *WidenableBR, Value *NewCond);
36
37/// Given a branch we know is widenable (defined per Analysis/GuardUtils.h),
38/// *set* it's condition such that (only) 'Cond' is known to hold on the taken
39/// path and that the branch remains widenable after transform.
40void setWidenableBranchCond(BranchInst *WidenableBR, Value *Cond);
41
42} // llvm
43
44#endif // LLVM_TRANSFORMS_UTILS_GUARDUTILS_H
45