LLVM  12.0.0git
GuardUtils.h
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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 analyzes related to guards and their
9 // conditions.
10 //===----------------------------------------------------------------------===//
11 
12 #ifndef LLVM_ANALYSIS_GUARDUTILS_H
13 #define LLVM_ANALYSIS_GUARDUTILS_H
14 
15 namespace llvm {
16 
17 class BasicBlock;
18 class Use;
19 class User;
20 class Value;
21 
22 /// Returns true iff \p U has semantics of a guard expressed in a form of call
23 /// of llvm.experimental.guard intrinsic.
24 bool isGuard(const User *U);
25 
26 /// Returns true iff \p U is a widenable branch (that is, parseWidenableBranch
27 /// returns true).
28 bool isWidenableBranch(const User *U);
29 
30 /// Returns true iff \p U has semantics of a guard expressed in a form of a
31 /// widenable conditional branch to deopt block.
32 bool isGuardAsWidenableBranch(const User *U);
33 
34 /// If U is widenable branch looking like:
35 /// %cond = ...
36 /// %wc = call i1 @llvm.experimental.widenable.condition()
37 /// %branch_cond = and i1 %cond, %wc
38 /// br i1 %branch_cond, label %if_true_bb, label %if_false_bb ; <--- U
39 /// The function returns true, and the values %cond and %wc and blocks
40 /// %if_true_bb, if_false_bb are returned in
41 /// the parameters (Condition, WidenableCondition, IfTrueBB and IfFalseFF)
42 /// respectively. If \p U does not match this pattern, return false.
43 bool parseWidenableBranch(const User *U, Value *&Condition,
44  Value *&WidenableCondition, BasicBlock *&IfTrueBB,
45  BasicBlock *&IfFalseBB);
46 
47 /// Analgous to the above, but return the Uses so that that they can be
48 /// modified. Unlike previous version, Condition is optional and may be null.
49 bool parseWidenableBranch(User *U, Use *&Cond, Use *&WC, BasicBlock *&IfTrueBB,
50  BasicBlock *&IfFalseBB);
51 
52 } // llvm
53 
54 #endif // LLVM_ANALYSIS_GUARDUTILS_H
bool isWidenableBranch(const User *U)
Returns true iff U is a widenable branch (that is, parseWidenableBranch returns true).
Definition: GuardUtils.cpp:22
This class represents lattice values for constants.
Definition: AllocatorList.h:23
Various leaf nodes.
Definition: ISDOpcodes.h:64
SmallVector< MachineOperand, 4 > Cond
bool parseWidenableBranch(const User *U, Value *&Condition, Value *&WidenableCondition, BasicBlock *&IfTrueBB, BasicBlock *&IfFalseBB)
If U is widenable branch looking like: cond = ...
Definition: GuardUtils.cpp:44
bool isGuard(const User *U)
Returns true iff U has semantics of a guard expressed in a form of call of llvm.experimental.guard intrinsic.
Definition: GuardUtils.cpp:18
could "use" a pointer
bool isGuardAsWidenableBranch(const User *U)
Returns true iff U has semantics of a guard expressed in a form of a widenable conditional branch to ...
Definition: GuardUtils.cpp:29