1 //===-- ARMMachineFunctionInfo.cpp - ARM machine function info ------------===//
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 #include "ARMMachineFunctionInfo.h"
10 #include "ARMSubtarget.h"
11
12 using namespace llvm;
13
anchor()14 void ARMFunctionInfo::anchor() {}
15
ARMFunctionInfo(const llvm::ARMFunctionInfo & MFI)16 yaml::ARMFunctionInfo::ARMFunctionInfo(const llvm::ARMFunctionInfo &MFI)
17 : LRSpilled(MFI.isLRSpilled()) {}
18
mappingImpl(yaml::IO & YamlIO)19 void yaml::ARMFunctionInfo::mappingImpl(yaml::IO &YamlIO) {
20 MappingTraits<ARMFunctionInfo>::mapping(YamlIO, *this);
21 }
22
initializeBaseYamlFields(const yaml::ARMFunctionInfo & YamlMFI)23 void ARMFunctionInfo::initializeBaseYamlFields(
24 const yaml::ARMFunctionInfo &YamlMFI) {
25 LRSpilled = YamlMFI.LRSpilled;
26 }
27
GetBranchTargetEnforcement(const Function & F,const ARMSubtarget * Subtarget)28 static bool GetBranchTargetEnforcement(const Function &F,
29 const ARMSubtarget *Subtarget) {
30 if (!Subtarget->isMClass() || !Subtarget->hasV7Ops())
31 return false;
32
33 if (!F.hasFnAttribute("branch-target-enforcement")) {
34 if (const auto *BTE = mdconst::extract_or_null<ConstantInt>(
35 F.getParent()->getModuleFlag("branch-target-enforcement")))
36 return BTE->getZExtValue();
37 return false;
38 }
39
40 const StringRef BTIEnable =
41 F.getFnAttribute("branch-target-enforcement").getValueAsString();
42 assert(BTIEnable == "true" || BTIEnable == "false");
43 return BTIEnable == "true";
44 }
45
46 // The pair returns values for the ARMFunctionInfo members
47 // SignReturnAddress and SignReturnAddressAll respectively.
GetSignReturnAddress(const Function & F)48 static std::pair<bool, bool> GetSignReturnAddress(const Function &F) {
49 if (!F.hasFnAttribute("sign-return-address")) {
50 const Module &M = *F.getParent();
51 if (const auto *Sign = mdconst::extract_or_null<ConstantInt>(
52 M.getModuleFlag("sign-return-address"))) {
53 if (Sign->getZExtValue()) {
54 if (const auto *All = mdconst::extract_or_null<ConstantInt>(
55 M.getModuleFlag("sign-return-address-all")))
56 return {true, All->getZExtValue()};
57 return {true, false};
58 }
59 }
60 return {false, false};
61 }
62
63 StringRef Scope = F.getFnAttribute("sign-return-address").getValueAsString();
64 if (Scope.equals("none"))
65 return {false, false};
66
67 if (Scope.equals("all"))
68 return {true, true};
69
70 assert(Scope.equals("non-leaf"));
71 return {true, false};
72 }
73
ARMFunctionInfo(const Function & F,const ARMSubtarget * Subtarget)74 ARMFunctionInfo::ARMFunctionInfo(const Function &F,
75 const ARMSubtarget *Subtarget)
76 : isThumb(Subtarget->isThumb()), hasThumb2(Subtarget->hasThumb2()),
77 IsCmseNSEntry(F.hasFnAttribute("cmse_nonsecure_entry")),
78 IsCmseNSCall(F.hasFnAttribute("cmse_nonsecure_call")),
79 BranchTargetEnforcement(GetBranchTargetEnforcement(F, Subtarget)) {
80 if (Subtarget->isMClass() && Subtarget->hasV7Ops())
81 std::tie(SignReturnAddress, SignReturnAddressAll) = GetSignReturnAddress(F);
82 }
83
84 MachineFunctionInfo *
clone(BumpPtrAllocator & Allocator,MachineFunction & DestMF,const DenseMap<MachineBasicBlock *,MachineBasicBlock * > & Src2DstMBB) const85 ARMFunctionInfo::clone(BumpPtrAllocator &Allocator, MachineFunction &DestMF,
86 const DenseMap<MachineBasicBlock *, MachineBasicBlock *>
87 &Src2DstMBB) const {
88 return DestMF.cloneInfo<ARMFunctionInfo>(*this);
89 }
90