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llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
| Show First 20 Lines • Show All 5,836 Lines • ▼ Show 20 Lines | AArch64InstrInfo::findRegisterToSaveLRTo(const outliner::Candidate &C) const { | |||||||||
| // No suitable register. Return 0. | // No suitable register. Return 0. | |||||||||
| return 0u; | return 0u; | |||||||||
| } | } | |||||||||
| static bool | static bool | |||||||||
| outliningCandidatesSigningScopeConsensus(const outliner::Candidate &a, | outliningCandidatesSigningScopeConsensus(const outliner::Candidate &a, | |||||||||
| const outliner::Candidate &b) { | const outliner::Candidate &b) { | |||||||||
| const Function &Fa = a.getMF()->getFunction(); | const auto &MFIa = a.getMF()->getInfo<AArch64FunctionInfo>(); | |||||||||
| const Function &Fb = b.getMF()->getFunction(); | const auto &MFIb = b.getMF()->getInfo<AArch64FunctionInfo>(); | |||||||||
tellenbach: Is this a typo?
| ||||||||||
D'oh, bloody copy/paste. Good catch, thanks! chill: D'oh, bloody copy/paste. Good catch, thanks! | ||||||||||
| // If none of the functions have the "sign-return-address" attribute their | return MFIa->shouldSignReturnAddress(false) == MFIb->shouldSignReturnAddress(false) && | |||||||||
| // signing behaviour is equal | MFIa->shouldSignReturnAddress(true) == MFIb->shouldSignReturnAddress(true); | |||||||||
| if (!Fa.hasFnAttribute("sign-return-address") && | ||||||||||
| !Fb.hasFnAttribute("sign-return-address")) { | ||||||||||
| return true; | ||||||||||
| } | ||||||||||
| // If both functions have the "sign-return-address" attribute their signing | ||||||||||
| // behaviour is equal, if the values of the attributes are equal | ||||||||||
| if (Fa.hasFnAttribute("sign-return-address") && | ||||||||||
| Fb.hasFnAttribute("sign-return-address")) { | ||||||||||
| StringRef ScopeA = | ||||||||||
| Fa.getFnAttribute("sign-return-address").getValueAsString(); | ||||||||||
| StringRef ScopeB = | ||||||||||
| Fb.getFnAttribute("sign-return-address").getValueAsString(); | ||||||||||
| return ScopeA.equals(ScopeB); | ||||||||||
| } | ||||||||||
| // If function B doesn't have the "sign-return-address" attribute but A does, | ||||||||||
| // the functions' signing behaviour is equal if A's value for | ||||||||||
| // "sign-return-address" is "none" and vice versa. | ||||||||||
| if (Fa.hasFnAttribute("sign-return-address")) { | ||||||||||
| StringRef ScopeA = | ||||||||||
| Fa.getFnAttribute("sign-return-address").getValueAsString(); | ||||||||||
| return ScopeA.equals("none"); | ||||||||||
| } | ||||||||||
| if (Fb.hasFnAttribute("sign-return-address")) { | ||||||||||
| StringRef ScopeB = | ||||||||||
| Fb.getFnAttribute("sign-return-address").getValueAsString(); | ||||||||||
| return ScopeB.equals("none"); | ||||||||||
| } | ||||||||||
| llvm_unreachable("Unkown combination of sign-return-address attributes"); | ||||||||||
| } | } | |||||||||
| static bool | static bool | |||||||||
| outliningCandidatesSigningKeyConsensus(const outliner::Candidate &a, | outliningCandidatesSigningKeyConsensus(const outliner::Candidate &a, | |||||||||
| const outliner::Candidate &b) { | const outliner::Candidate &b) { | |||||||||
| const Function &Fa = a.getMF()->getFunction(); | const auto &MFIa = a.getMF()->getInfo<AArch64FunctionInfo>(); | |||||||||
| const Function &Fb = b.getMF()->getFunction(); | const auto &MFIb = b.getMF()->getInfo<AArch64FunctionInfo>(); | |||||||||
Same. tellenbach: Same. | ||||||||||
| // If none of the functions have the "sign-return-address-key" attribute | ||||||||||
| // their keys are equal | ||||||||||
| if (!Fa.hasFnAttribute("sign-return-address-key") && | ||||||||||
| !Fb.hasFnAttribute("sign-return-address-key")) { | ||||||||||
| return true; | ||||||||||
| } | ||||||||||
| // If both functions have the "sign-return-address-key" attribute their | ||||||||||
| // keys are equal if the values of "sign-return-address-key" are equal | ||||||||||
| if (Fa.hasFnAttribute("sign-return-address-key") && | ||||||||||
| Fb.hasFnAttribute("sign-return-address-key")) { | ||||||||||
| StringRef KeyA = | ||||||||||
| Fa.getFnAttribute("sign-return-address-key").getValueAsString(); | ||||||||||
| StringRef KeyB = | ||||||||||
| Fb.getFnAttribute("sign-return-address-key").getValueAsString(); | ||||||||||
| return KeyA.equals(KeyB); | ||||||||||
| } | ||||||||||
| // If B doesn't have the "sign-return-address-key" attribute, both keys are | ||||||||||
| // equal, if function a has the default key (a_key) | ||||||||||
| if (Fa.hasFnAttribute("sign-return-address-key")) { | ||||||||||
| StringRef KeyA = | ||||||||||
| Fa.getFnAttribute("sign-return-address-key").getValueAsString(); | ||||||||||
| return KeyA.equals_lower("a_key"); | ||||||||||
| } | ||||||||||
| if (Fb.hasFnAttribute("sign-return-address-key")) { | ||||||||||
| StringRef KeyB = | ||||||||||
| Fb.getFnAttribute("sign-return-address-key").getValueAsString(); | ||||||||||
| return KeyB.equals_lower("a_key"); | ||||||||||
| } | ||||||||||
| llvm_unreachable("Unkown combination of sign-return-address-key attributes"); | return MFIa->shouldSignWithBKey() == MFIb->shouldSignWithBKey(); | |||||||||
| } | } | |||||||||
| static bool outliningCandidatesV8_3OpsConsensus(const outliner::Candidate &a, | static bool outliningCandidatesV8_3OpsConsensus(const outliner::Candidate &a, | |||||||||
| const outliner::Candidate &b) { | const outliner::Candidate &b) { | |||||||||
| const AArch64Subtarget &SubtargetA = | const AArch64Subtarget &SubtargetA = | |||||||||
| a.getMF()->getSubtarget<AArch64Subtarget>(); | a.getMF()->getSubtarget<AArch64Subtarget>(); | |||||||||
| const AArch64Subtarget &SubtargetB = | const AArch64Subtarget &SubtargetB = | |||||||||
| b.getMF()->getSubtarget<AArch64Subtarget>(); | b.getMF()->getSubtarget<AArch64Subtarget>(); | |||||||||
| Show All 39 Lines | outliner::OutlinedFunction AArch64InstrInfo::getOutliningCandidateInfo( | |||||||||
| // the case of "sign-return-address"="non-leaf" this is an assumption: It is | // the case of "sign-return-address"="non-leaf" this is an assumption: It is | |||||||||
| // not certainly true that the outlined function will have to sign its return | // not certainly true that the outlined function will have to sign its return | |||||||||
| // address but this decision is made later, when the decision to outline | // address but this decision is made later, when the decision to outline | |||||||||
| // has already been made. | // has already been made. | |||||||||
| // The same holds for the number of additional instructions we need: On | // The same holds for the number of additional instructions we need: On | |||||||||
| // v8.3a RET can be replaced by RETAA/RETAB and no AUT instruction is | // v8.3a RET can be replaced by RETAA/RETAB and no AUT instruction is | |||||||||
| // necessary. However, at this point we don't know if the outlined function | // necessary. However, at this point we don't know if the outlined function | |||||||||
| // will have a RET instruction so we assume the worst. | // will have a RET instruction so we assume the worst. | |||||||||
| const Function &FCF = FirstCand.getMF()->getFunction(); | ||||||||||
| const TargetRegisterInfo &TRI = getRegisterInfo(); | const TargetRegisterInfo &TRI = getRegisterInfo(); | |||||||||
| if (FCF.hasFnAttribute("sign-return-address")) { | if (FirstCand.getMF() | |||||||||
| ->getInfo<AArch64FunctionInfo>() | ||||||||||
| ->shouldSignReturnAddress(true)) { | ||||||||||
| // One PAC and one AUT instructions | // One PAC and one AUT instructions | |||||||||
| NumBytesToCreateFrame += 8; | NumBytesToCreateFrame += 8; | |||||||||
| // We have to check if sp modifying instructions would get outlined. | // We have to check if sp modifying instructions would get outlined. | |||||||||
| // If so we only allow outlining if sp is unchanged overall, so matching | // If so we only allow outlining if sp is unchanged overall, so matching | |||||||||
| // sub and add instructions are okay to outline, all other sp modifications | // sub and add instructions are okay to outline, all other sp modifications | |||||||||
| // are not | // are not | |||||||||
| auto hasIllegalSPModification = [&TRI](outliner::Candidate &C) { | auto hasIllegalSPModification = [&TRI](outliner::Candidate &C) { | |||||||||
| ▲ Show 20 Lines • Show All 112 Lines • ▼ Show 20 Lines | auto SetCandidateCallInfo = | |||||||||
| for (outliner::Candidate &C : RepeatedSequenceLocs) | for (outliner::Candidate &C : RepeatedSequenceLocs) | |||||||||
| C.setCallInfo(CallID, NumBytesForCall); | C.setCallInfo(CallID, NumBytesForCall); | |||||||||
| }; | }; | |||||||||
| unsigned FrameID = MachineOutlinerDefault; | unsigned FrameID = MachineOutlinerDefault; | |||||||||
| NumBytesToCreateFrame += 4; | NumBytesToCreateFrame += 4; | |||||||||
| bool HasBTI = any_of(RepeatedSequenceLocs, [](outliner::Candidate &C) { | bool HasBTI = any_of(RepeatedSequenceLocs, [](outliner::Candidate &C) { | |||||||||
| return C.getMF()->getFunction().hasFnAttribute("branch-target-enforcement"); | return C.getMF()->getInfo<AArch64FunctionInfo>()->branchTargetEnforcement(); | |||||||||
| }); | }); | |||||||||
| // We check to see if CFI Instructions are present, and if they are | // We check to see if CFI Instructions are present, and if they are | |||||||||
| // we find the number of CFI Instructions in the candidates. | // we find the number of CFI Instructions in the candidates. | |||||||||
| unsigned CFICount = 0; | unsigned CFICount = 0; | |||||||||
| MachineBasicBlock::iterator MBBI = RepeatedSequenceLocs[0].front(); | MachineBasicBlock::iterator MBBI = RepeatedSequenceLocs[0].front(); | |||||||||
| for (unsigned Loc = RepeatedSequenceLocs[0].getStartIdx(); | for (unsigned Loc = RepeatedSequenceLocs[0].getStartIdx(); | |||||||||
| Loc < RepeatedSequenceLocs[0].getEndIdx() + 1; Loc++) { | Loc < RepeatedSequenceLocs[0].getEndIdx() + 1; Loc++) { | |||||||||
| ▲ Show 20 Lines • Show All 688 Lines • ▼ Show 20 Lines | MachineInstr *LDRXpost = BuildMI(MF, DebugLoc(), get(AArch64::LDRXpost)) | |||||||||
| .addReg(AArch64::SP) | .addReg(AArch64::SP) | |||||||||
| .addImm(16); | .addImm(16); | |||||||||
| Et = MBB.insert(Et, LDRXpost); | Et = MBB.insert(Et, LDRXpost); | |||||||||
| } | } | |||||||||
| // If a bunch of candidates reach this point they must agree on their return | // If a bunch of candidates reach this point they must agree on their return | |||||||||
| // address signing. It is therefore enough to just consider the signing | // address signing. It is therefore enough to just consider the signing | |||||||||
| // behaviour of one of them | // behaviour of one of them | |||||||||
| const Function &CF = OF.Candidates.front().getMF()->getFunction(); | const auto &MFI = *OF.Candidates.front().getMF()->getInfo<AArch64FunctionInfo>(); | |||||||||
| bool ShouldSignReturnAddr = false; | bool ShouldSignReturnAddr = MFI.shouldSignReturnAddress(!IsLeafFunction); | |||||||||
| if (CF.hasFnAttribute("sign-return-address")) { | ||||||||||
| StringRef Scope = | ||||||||||
| CF.getFnAttribute("sign-return-address").getValueAsString(); | ||||||||||
| if (Scope.equals("all")) | ||||||||||
| ShouldSignReturnAddr = true; | ||||||||||
| else if (Scope.equals("non-leaf") && !IsLeafFunction) | ||||||||||
| ShouldSignReturnAddr = true; | ||||||||||
| } | ||||||||||
| // a_key is the default | // a_key is the default | |||||||||
| bool ShouldSignReturnAddrWithAKey = true; | bool ShouldSignReturnAddrWithAKey = !MFI.shouldSignWithBKey(); | |||||||||
| if (CF.hasFnAttribute("sign-return-address-key")) { | ||||||||||
| const StringRef Key = | ||||||||||
| CF.getFnAttribute("sign-return-address-key").getValueAsString(); | ||||||||||
| // Key can either be a_key or b_key | ||||||||||
| assert((Key.equals_lower("a_key") || Key.equals_lower("b_key")) && | ||||||||||
| "Return address signing key must be either a_key or b_key"); | ||||||||||
| ShouldSignReturnAddrWithAKey = Key.equals_lower("a_key"); | ||||||||||
| } | ||||||||||
| // If this is a tail call outlined function, then there's already a return. | // If this is a tail call outlined function, then there's already a return. | |||||||||
| if (OF.FrameConstructionID == MachineOutlinerTailCall || | if (OF.FrameConstructionID == MachineOutlinerTailCall || | |||||||||
| OF.FrameConstructionID == MachineOutlinerThunk) { | OF.FrameConstructionID == MachineOutlinerThunk) { | |||||||||
| signOutlinedFunction(MF, MBB, ShouldSignReturnAddr, | signOutlinedFunction(MF, MBB, ShouldSignReturnAddr, | |||||||||
| ShouldSignReturnAddrWithAKey); | ShouldSignReturnAddrWithAKey); | |||||||||
| return; | return; | |||||||||
| } | } | |||||||||
| ▲ Show 20 Lines • Show All 238 Lines • Show Last 20 Lines | ||||||||||
Is this a typo?