llvm/lib/Target/ARM/ARMMachineFunctionInfo.cpp

   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
  14 void ARMFunctionInfo::anchor() {}
  15
  16 yaml::ARMFunctionInfo::ARMFunctionInfo(const llvm::ARMFunctionInfo &MFI)
  17     : LRSpilled(MFI.isLRSpilled()) {}
  18
  19 void yaml::ARMFunctionInfo::mappingImpl(yaml::IO &YamlIO) {
  20   MappingTraits<ARMFunctionInfo>::mapping(YamlIO, *this);
  21 }
  22
  23 void ARMFunctionInfo::initializeBaseYamlFields(
  24     const yaml::ARMFunctionInfo &YamlMFI) {
  25   LRSpilled = YamlMFI.LRSpilled;
  26 }
  27
  28 static bool GetBranchTargetEnforcement(const Function &F,
  29                                        const ARMSubtarget *Subtarget) {
  30   if (!Subtarget->isMClass() || !Subtarget->hasV7Ops())
  31     return false;
  32
  33   return F.hasFnAttribute("branch-target-enforcement");
  34 }
  35
  36 // The pair returns values for the ARMFunctionInfo members
  37 // SignReturnAddress and SignReturnAddressAll respectively.
  38 static std::pair<bool, bool> GetSignReturnAddress(const Function &F) {
  39   if (!F.hasFnAttribute("sign-return-address")) {
  40     return {false, false};
  41   }
  42
  43   StringRef Scope = F.getFnAttribute("sign-return-address").getValueAsString();
  44   if (Scope == "none")
  45     return {false, false};
  46
  47   if (Scope == "all")
  48     return {true, true};
  49
  50   assert(Scope == "non-leaf");
  51   return {true, false};
  52 }
  53
  54 ARMFunctionInfo::ARMFunctionInfo(const Function &F,
  55                                  const ARMSubtarget *Subtarget)
  56     : isThumb(Subtarget->isThumb()), hasThumb2(Subtarget->hasThumb2()),
  57       IsCmseNSEntry(F.hasFnAttribute("cmse_nonsecure_entry")),
  58       IsCmseNSCall(F.hasFnAttribute("cmse_nonsecure_call")),
  59       BranchTargetEnforcement(GetBranchTargetEnforcement(F, Subtarget)) {
  60   if (Subtarget->isMClass() && Subtarget->hasV7Ops())
  61     std::tie(SignReturnAddress, SignReturnAddressAll) = GetSignReturnAddress(F);
  62 }
  63
  64 MachineFunctionInfo *
  65 ARMFunctionInfo::clone(BumpPtrAllocator &Allocator, MachineFunction &DestMF,
  66                        const DenseMap<MachineBasicBlock *, MachineBasicBlock *>
  67                            &Src2DstMBB) const {
  68   return DestMF.cloneInfo<ARMFunctionInfo>(*this);
  69 }