| //===-- ARMMachineFunctionInfo.cpp - ARM machine function info ------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "ARMMachineFunctionInfo.h" |
| #include "ARMSubtarget.h" |
| |
| using namespace llvm; |
| |
| void ARMFunctionInfo::anchor() {} |
| |
| static bool GetBranchTargetEnforcement(const Function &F, |
| const ARMSubtarget *Subtarget) { |
| if (!Subtarget->isMClass() || !Subtarget->hasV7Ops()) |
| return false; |
| |
| if (!F.hasFnAttribute("branch-target-enforcement")) { |
| if (const auto *BTE = mdconst::extract_or_null<ConstantInt>( |
| F.getParent()->getModuleFlag("branch-target-enforcement"))) |
| return BTE->getZExtValue(); |
| return false; |
| } |
| |
| const StringRef BTIEnable = |
| F.getFnAttribute("branch-target-enforcement").getValueAsString(); |
| assert(BTIEnable.equals_insensitive("true") || |
| BTIEnable.equals_insensitive("false")); |
| return BTIEnable.equals_insensitive("true"); |
| } |
| |
| // The pair returns values for the ARMFunctionInfo members |
| // SignReturnAddress and SignReturnAddressAll respectively. |
| static std::pair<bool, bool> GetSignReturnAddress(const Function &F) { |
| if (!F.hasFnAttribute("sign-return-address")) { |
| const Module &M = *F.getParent(); |
| if (const auto *Sign = mdconst::extract_or_null<ConstantInt>( |
| M.getModuleFlag("sign-return-address"))) { |
| if (Sign->getZExtValue()) { |
| if (const auto *All = mdconst::extract_or_null<ConstantInt>( |
| M.getModuleFlag("sign-return-address-all"))) |
| return {true, All->getZExtValue()}; |
| return {true, false}; |
| } |
| } |
| return {false, false}; |
| } |
| |
| StringRef Scope = F.getFnAttribute("sign-return-address").getValueAsString(); |
| if (Scope.equals("none")) |
| return {false, false}; |
| |
| if (Scope.equals("all")) |
| return {true, true}; |
| |
| assert(Scope.equals("non-leaf")); |
| return {true, false}; |
| } |
| |
| ARMFunctionInfo::ARMFunctionInfo(const Function &F, |
| const ARMSubtarget *Subtarget) |
| : isThumb(Subtarget->isThumb()), hasThumb2(Subtarget->hasThumb2()), |
| IsCmseNSEntry(F.hasFnAttribute("cmse_nonsecure_entry")), |
| IsCmseNSCall(F.hasFnAttribute("cmse_nonsecure_call")), |
| BranchTargetEnforcement(GetBranchTargetEnforcement(F, Subtarget)) { |
| if (Subtarget->isMClass() && Subtarget->hasV7Ops()) |
| std::tie(SignReturnAddress, SignReturnAddressAll) = GetSignReturnAddress(F); |
| } |
| |
| MachineFunctionInfo * |
| ARMFunctionInfo::clone(BumpPtrAllocator &Allocator, MachineFunction &DestMF, |
| const DenseMap<MachineBasicBlock *, MachineBasicBlock *> |
| &Src2DstMBB) const { |
| return DestMF.cloneInfo<ARMFunctionInfo>(*this); |
| } |