1 //===- SCCP.h - Sparse Conditional Constant Propagation ---------*- 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 //
9 // This pass implements  interprocedural sparse conditional constant
10 // propagation and merging.
11 //
12 // Specifically, this:
13 //   * Assumes values are constant unless proven otherwise
14 //   * Assumes BasicBlocks are dead unless proven otherwise
15 //   * Proves values to be constant, and replaces them with constants
16 //   * Proves conditional branches to be unconditional
17 //
18 //===----------------------------------------------------------------------===//
19 
20 #ifndef LLVM_TRANSFORMS_IPO_SCCP_H
21 #define LLVM_TRANSFORMS_IPO_SCCP_H
22 
23 #include "llvm/IR/PassManager.h"
24 
25 namespace llvm {
26 
27 class Module;
28 
29 /// A set of parameters to control various transforms performed by IPSCCP pass.
30 /// Each of the boolean parameters can be set to:
31 ///   true - enabling the transformation.
32 ///   false - disabling the transformation.
33 /// Intended use is to create a default object, modify parameters with
34 /// additional setters and then pass it to IPSCCP.
35 struct IPSCCPOptions {
36   bool AllowFuncSpec;
37 
38   IPSCCPOptions(bool AllowFuncSpec = true) : AllowFuncSpec(AllowFuncSpec) {}
39 
40   /// Enables or disables Specialization of Functions.
41   IPSCCPOptions &setFuncSpec(bool FuncSpec) {
42     AllowFuncSpec = FuncSpec;
43     return *this;
44   }
45 };
46 
47 /// Pass to perform interprocedural constant propagation.
48 class IPSCCPPass : public PassInfoMixin<IPSCCPPass> {
49   IPSCCPOptions Options;
50 
51 public:
52   IPSCCPPass() = default;
53 
54   IPSCCPPass(IPSCCPOptions Options) : Options(Options) {}
55 
56   PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM);
57 
58   bool isFuncSpecEnabled() const { return Options.AllowFuncSpec; }
59 };
60 
61 } // end namespace llvm
62 
63 #endif // LLVM_TRANSFORMS_IPO_SCCP_H
64