#pragma once #ifdef __GNUC__ #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wunused-parameter" #endif //===-- CodeGen/MachineFrameInfo.h - Abstract Stack Frame Rep. --*- C++ -*-===// // // 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 // //===----------------------------------------------------------------------===// // // The file defines the MachineFrameInfo class. // //===----------------------------------------------------------------------===// #ifndef LLVM_CODEGEN_MACHINEFRAMEINFO_H #define LLVM_CODEGEN_MACHINEFRAMEINFO_H #include "llvm/ADT/SmallVector.h" #include "llvm/CodeGen/Register.h" #include "llvm/Support/Alignment.h" #include "llvm/Support/DataTypes.h" #include #include namespace llvm { class raw_ostream; class MachineFunction; class MachineBasicBlock; class BitVector; class AllocaInst; /// The CalleeSavedInfo class tracks the information need to locate where a /// callee saved register is in the current frame. /// Callee saved reg can also be saved to a different register rather than /// on the stack by setting DstReg instead of FrameIdx. class CalleeSavedInfo { Register Reg; union { int FrameIdx; unsigned DstReg; }; /// Flag indicating whether the register is actually restored in the epilog. /// In most cases, if a register is saved, it is also restored. There are /// some situations, though, when this is not the case. For example, the /// LR register on ARM is usually saved, but on exit from the function its /// saved value may be loaded directly into PC. Since liveness tracking of /// physical registers treats callee-saved registers are live outside of /// the function, LR would be treated as live-on-exit, even though in these /// scenarios it is not. This flag is added to indicate that the saved /// register described by this object is not restored in the epilog. /// The long-term solution is to model the liveness of callee-saved registers /// by implicit uses on the return instructions, however, the required /// changes in the ARM backend would be quite extensive. bool Restored = true; /// Flag indicating whether the register is spilled to stack or another /// register. bool SpilledToReg = false; public: explicit CalleeSavedInfo(unsigned R, int FI = 0) : Reg(R), FrameIdx(FI) {} // Accessors. Register getReg() const { return Reg; } int getFrameIdx() const { return FrameIdx; } unsigned getDstReg() const { return DstReg; } void setFrameIdx(int FI) { FrameIdx = FI; SpilledToReg = false; } void setDstReg(Register SpillReg) { DstReg = SpillReg; SpilledToReg = true; } bool isRestored() const { return Restored; } void setRestored(bool R) { Restored = R; } bool isSpilledToReg() const { return SpilledToReg; } }; /// The MachineFrameInfo class represents an abstract stack frame until /// prolog/epilog code is inserted. This class is key to allowing stack frame /// representation optimizations, such as frame pointer elimination. It also /// allows more mundane (but still important) optimizations, such as reordering /// of abstract objects on the stack frame. /// /// To support this, the class assigns unique integer identifiers to stack /// objects requested clients. These identifiers are negative integers for /// fixed stack objects (such as arguments passed on the stack) or nonnegative /// for objects that may be reordered. Instructions which refer to stack /// objects use a special MO_FrameIndex operand to represent these frame /// indexes. /// /// Because this class keeps track of all references to the stack frame, it /// knows when a variable sized object is allocated on the stack. This is the /// sole condition which prevents frame pointer elimination, which is an /// important optimization on register-poor architectures. Because original /// variable sized alloca's in the source program are the only source of /// variable sized stack objects, it is safe to decide whether there will be /// any variable sized objects before all stack objects are known (for /// example, register allocator spill code never needs variable sized /// objects). /// /// When prolog/epilog code emission is performed, the final stack frame is /// built and the machine instructions are modified to refer to the actual /// stack offsets of the object, eliminating all MO_FrameIndex operands from /// the program. /// /// Abstract Stack Frame Information class MachineFrameInfo { public: /// Stack Smashing Protection (SSP) rules require that vulnerable stack /// allocations are located close the stack protector. enum SSPLayoutKind { SSPLK_None, ///< Did not trigger a stack protector. No effect on data ///< layout. SSPLK_LargeArray, ///< Array or nested array >= SSP-buffer-size. Closest ///< to the stack protector. SSPLK_SmallArray, ///< Array or nested array < SSP-buffer-size. 2nd closest ///< to the stack protector. SSPLK_AddrOf ///< The address of this allocation is exposed and ///< triggered protection. 3rd closest to the protector. }; private: // Represent a single object allocated on the stack. struct StackObject { // The offset of this object from the stack pointer on entry to // the function. This field has no meaning for a variable sized element. int64_t SPOffset; // The size of this object on the stack. 0 means a variable sized object, // ~0ULL means a dead object. uint64_t Size; // The required alignment of this stack slot. Align Alignment; // If true, the value of the stack object is set before // entering the function and is not modified inside the function. By // default, fixed objects are immutable unless marked otherwise. bool isImmutable; // If true the stack object is used as spill slot. It // cannot alias any other memory objects. bool isSpillSlot; /// If true, this stack slot is used to spill a value (could be deopt /// and/or GC related) over a statepoint. We know that the address of the /// slot can't alias any LLVM IR value. This is very similar to a Spill /// Slot, but is created by statepoint lowering is SelectionDAG, not the /// register allocator. bool isStatepointSpillSlot = false; /// Identifier for stack memory type analagous to address space. If this is /// non-0, the meaning is target defined. Offsets cannot be directly /// compared between objects with different stack IDs. The object may not /// necessarily reside in the same contiguous memory block as other stack /// objects. Objects with differing stack IDs should not be merged or /// replaced substituted for each other. // /// It is assumed a target uses consecutive, increasing stack IDs starting /// from 1. uint8_t StackID; /// If this stack object is originated from an Alloca instruction /// this value saves the original IR allocation. Can be NULL. const AllocaInst *Alloca; // If true, the object was mapped into the local frame // block and doesn't need additional handling for allocation beyond that. bool PreAllocated = false; // If true, an LLVM IR value might point to this object. // Normally, spill slots and fixed-offset objects don't alias IR-accessible // objects, but there are exceptions (on PowerPC, for example, some byval // arguments have ABI-prescribed offsets). bool isAliased; /// If true, the object has been zero-extended. bool isZExt = false; /// If true, the object has been sign-extended. bool isSExt = false; uint8_t SSPLayout = SSPLK_None; StackObject(uint64_t Size, Align Alignment, int64_t SPOffset, bool IsImmutable, bool IsSpillSlot, const AllocaInst *Alloca, bool IsAliased, uint8_t StackID = 0) : SPOffset(SPOffset), Size(Size), Alignment(Alignment), isImmutable(IsImmutable), isSpillSlot(IsSpillSlot), StackID(StackID), Alloca(Alloca), isAliased(IsAliased) {} }; /// The alignment of the stack. Align StackAlignment; /// Can the stack be realigned. This can be false if the target does not /// support stack realignment, or if the user asks us not to realign the /// stack. In this situation, overaligned allocas are all treated as dynamic /// allocations and the target must handle them as part of DYNAMIC_STACKALLOC /// lowering. All non-alloca stack objects have their alignment clamped to the /// base ABI stack alignment. /// FIXME: There is room for improvement in this case, in terms of /// grouping overaligned allocas into a "secondary stack frame" and /// then only use a single alloca to allocate this frame and only a /// single virtual register to access it. Currently, without such an /// optimization, each such alloca gets its own dynamic realignment. bool StackRealignable; /// Whether the function has the \c alignstack attribute. bool ForcedRealign; /// The list of stack objects allocated. std::vector Objects; /// This contains the number of fixed objects contained on /// the stack. Because fixed objects are stored at a negative index in the /// Objects list, this is also the index to the 0th object in the list. unsigned NumFixedObjects = 0; /// This boolean keeps track of whether any variable /// sized objects have been allocated yet. bool HasVarSizedObjects = false; /// This boolean keeps track of whether there is a call /// to builtin \@llvm.frameaddress. bool FrameAddressTaken = false; /// This boolean keeps track of whether there is a call /// to builtin \@llvm.returnaddress. bool ReturnAddressTaken = false; /// This boolean keeps track of whether there is a call /// to builtin \@llvm.experimental.stackmap. bool HasStackMap = false; /// This boolean keeps track of whether there is a call /// to builtin \@llvm.experimental.patchpoint. bool HasPatchPoint = false; /// The prolog/epilog code inserter calculates the final stack /// offsets for all of the fixed size objects, updating the Objects list /// above. It then updates StackSize to contain the number of bytes that need /// to be allocated on entry to the function. uint64_t StackSize = 0; /// The amount that a frame offset needs to be adjusted to /// have the actual offset from the stack/frame pointer. The exact usage of /// this is target-dependent, but it is typically used to adjust between /// SP-relative and FP-relative offsets. E.G., if objects are accessed via /// SP then OffsetAdjustment is zero; if FP is used, OffsetAdjustment is set /// to the distance between the initial SP and the value in FP. For many /// targets, this value is only used when generating debug info (via /// TargetRegisterInfo::getFrameIndexReference); when generating code, the /// corresponding adjustments are performed directly. int OffsetAdjustment = 0; /// The prolog/epilog code inserter may process objects that require greater /// alignment than the default alignment the target provides. /// To handle this, MaxAlignment is set to the maximum alignment /// needed by the objects on the current frame. If this is greater than the /// native alignment maintained by the compiler, dynamic alignment code will /// be needed. /// Align MaxAlignment; /// Set to true if this function adjusts the stack -- e.g., /// when calling another function. This is only valid during and after /// prolog/epilog code insertion. bool AdjustsStack = false; /// Set to true if this function has any function calls. bool HasCalls = false; /// The frame index for the stack protector. int StackProtectorIdx = -1; /// The frame index for the function context. Used for SjLj exceptions. int FunctionContextIdx = -1; /// This contains the size of the largest call frame if the target uses frame /// setup/destroy pseudo instructions (as defined in the TargetFrameInfo /// class). This information is important for frame pointer elimination. /// It is only valid during and after prolog/epilog code insertion. unsigned MaxCallFrameSize = ~0u; /// The number of bytes of callee saved registers that the target wants to /// report for the current function in the CodeView S_FRAMEPROC record. unsigned CVBytesOfCalleeSavedRegisters = 0; /// The prolog/epilog code inserter fills in this vector with each /// callee saved register saved in either the frame or a different /// register. Beyond its use by the prolog/ epilog code inserter, /// this data is used for debug info and exception handling. std::vector CSInfo; /// Has CSInfo been set yet? bool CSIValid = false; /// References to frame indices which are mapped /// into the local frame allocation block. SmallVector, 32> LocalFrameObjects; /// Size of the pre-allocated local frame block. int64_t LocalFrameSize = 0; /// Required alignment of the local object blob, which is the strictest /// alignment of any object in it. Align LocalFrameMaxAlign; /// Whether the local object blob needs to be allocated together. If not, /// PEI should ignore the isPreAllocated flags on the stack objects and /// just allocate them normally. bool UseLocalStackAllocationBlock = false; /// True if the function dynamically adjusts the stack pointer through some /// opaque mechanism like inline assembly or Win32 EH. bool HasOpaqueSPAdjustment = false; /// True if the function contains operations which will lower down to /// instructions which manipulate the stack pointer. bool HasCopyImplyingStackAdjustment = false; /// True if the function contains a call to the llvm.vastart intrinsic. bool HasVAStart = false; /// True if this is a varargs function that contains a musttail call. bool HasMustTailInVarArgFunc = false; /// True if this function contains a tail call. If so immutable objects like /// function arguments are no longer so. A tail call *can* override fixed /// stack objects like arguments so we can't treat them as immutable. bool HasTailCall = false; /// Not null, if shrink-wrapping found a better place for the prologue. MachineBasicBlock *Save = nullptr; /// Not null, if shrink-wrapping found a better place for the epilogue. MachineBasicBlock *Restore = nullptr; public: explicit MachineFrameInfo(unsigned StackAlignment, bool StackRealignable, bool ForcedRealign) : StackAlignment(assumeAligned(StackAlignment)), StackRealignable(StackRealignable), ForcedRealign(ForcedRealign) {} MachineFrameInfo(const MachineFrameInfo &) = delete; /// Return true if there are any stack objects in this function. bool hasStackObjects() const { return !Objects.empty(); } /// This method may be called any time after instruction /// selection is complete to determine if the stack frame for this function /// contains any variable sized objects. bool hasVarSizedObjects() const { return HasVarSizedObjects; } /// Return the index for the stack protector object. int getStackProtectorIndex() const { return StackProtectorIdx; } void setStackProtectorIndex(int I) { StackProtectorIdx = I; } bool hasStackProtectorIndex() const { return StackProtectorIdx != -1; } /// Return the index for the function context object. /// This object is used for SjLj exceptions. int getFunctionContextIndex() const { return FunctionContextIdx; } void setFunctionContextIndex(int I) { FunctionContextIdx = I; } /// This method may be called any time after instruction /// selection is complete to determine if there is a call to /// \@llvm.frameaddress in this function. bool isFrameAddressTaken() const { return FrameAddressTaken; } void setFrameAddressIsTaken(bool T) { FrameAddressTaken = T; } /// This method may be called any time after /// instruction selection is complete to determine if there is a call to /// \@llvm.returnaddress in this function. bool isReturnAddressTaken() const { return ReturnAddressTaken; } void setReturnAddressIsTaken(bool s) { ReturnAddressTaken = s; } /// This method may be called any time after instruction /// selection is complete to determine if there is a call to builtin /// \@llvm.experimental.stackmap. bool hasStackMap() const { return HasStackMap; } void setHasStackMap(bool s = true) { HasStackMap = s; } /// This method may be called any time after instruction /// selection is complete to determine if there is a call to builtin /// \@llvm.experimental.patchpoint. bool hasPatchPoint() const { return HasPatchPoint; } void setHasPatchPoint(bool s = true) { HasPatchPoint = s; } /// Return the minimum frame object index. int getObjectIndexBegin() const { return -NumFixedObjects; } /// Return one past the maximum frame object index. int getObjectIndexEnd() const { return (int)Objects.size()-NumFixedObjects; } /// Return the number of fixed objects. unsigned getNumFixedObjects() const { return NumFixedObjects; } /// Return the number of objects. unsigned getNumObjects() const { return Objects.size(); } /// Map a frame index into the local object block void mapLocalFrameObject(int ObjectIndex, int64_t Offset) { LocalFrameObjects.push_back(std::pair(ObjectIndex, Offset)); Objects[ObjectIndex + NumFixedObjects].PreAllocated = true; } /// Get the local offset mapping for a for an object. std::pair getLocalFrameObjectMap(int i) const { assert (i >= 0 && (unsigned)i < LocalFrameObjects.size() && "Invalid local object reference!"); return LocalFrameObjects[i]; } /// Return the number of objects allocated into the local object block. int64_t getLocalFrameObjectCount() const { return LocalFrameObjects.size(); } /// Set the size of the local object blob. void setLocalFrameSize(int64_t sz) { LocalFrameSize = sz; } /// Get the size of the local object blob. int64_t getLocalFrameSize() const { return LocalFrameSize; } /// Required alignment of the local object blob, /// which is the strictest alignment of any object in it. void setLocalFrameMaxAlign(Align Alignment) { LocalFrameMaxAlign = Alignment; } /// Return the required alignment of the local object blob. Align getLocalFrameMaxAlign() const { return LocalFrameMaxAlign; } /// Get whether the local allocation blob should be allocated together or /// let PEI allocate the locals in it directly. bool getUseLocalStackAllocationBlock() const { return UseLocalStackAllocationBlock; } /// setUseLocalStackAllocationBlock - Set whether the local allocation blob /// should be allocated together or let PEI allocate the locals in it /// directly. void setUseLocalStackAllocationBlock(bool v) { UseLocalStackAllocationBlock = v; } /// Return true if the object was pre-allocated into the local block. bool isObjectPreAllocated(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx+NumFixedObjects].PreAllocated; } /// Return the size of the specified object. int64_t getObjectSize(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx+NumFixedObjects].Size; } /// Change the size of the specified stack object. void setObjectSize(int ObjectIdx, int64_t Size) { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); Objects[ObjectIdx+NumFixedObjects].Size = Size; } /// Return the alignment of the specified stack object. Align getObjectAlign(int ObjectIdx) const { assert(unsigned(ObjectIdx + NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx + NumFixedObjects].Alignment; } /// setObjectAlignment - Change the alignment of the specified stack object. void setObjectAlignment(int ObjectIdx, Align Alignment) { assert(unsigned(ObjectIdx + NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); Objects[ObjectIdx + NumFixedObjects].Alignment = Alignment; // Only ensure max alignment for the default stack. if (getStackID(ObjectIdx) == 0) ensureMaxAlignment(Alignment); } /// Return the underlying Alloca of the specified /// stack object if it exists. Returns 0 if none exists. const AllocaInst* getObjectAllocation(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx+NumFixedObjects].Alloca; } /// Return the assigned stack offset of the specified object /// from the incoming stack pointer. int64_t getObjectOffset(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); assert(!isDeadObjectIndex(ObjectIdx) && "Getting frame offset for a dead object?"); return Objects[ObjectIdx+NumFixedObjects].SPOffset; } bool isObjectZExt(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx+NumFixedObjects].isZExt; } void setObjectZExt(int ObjectIdx, bool IsZExt) { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); Objects[ObjectIdx+NumFixedObjects].isZExt = IsZExt; } bool isObjectSExt(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx+NumFixedObjects].isSExt; } void setObjectSExt(int ObjectIdx, bool IsSExt) { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); Objects[ObjectIdx+NumFixedObjects].isSExt = IsSExt; } /// Set the stack frame offset of the specified object. The /// offset is relative to the stack pointer on entry to the function. void setObjectOffset(int ObjectIdx, int64_t SPOffset) { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); assert(!isDeadObjectIndex(ObjectIdx) && "Setting frame offset for a dead object?"); Objects[ObjectIdx+NumFixedObjects].SPOffset = SPOffset; } SSPLayoutKind getObjectSSPLayout(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return (SSPLayoutKind)Objects[ObjectIdx+NumFixedObjects].SSPLayout; } void setObjectSSPLayout(int ObjectIdx, SSPLayoutKind Kind) { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); assert(!isDeadObjectIndex(ObjectIdx) && "Setting SSP layout for a dead object?"); Objects[ObjectIdx+NumFixedObjects].SSPLayout = Kind; } /// Return the number of bytes that must be allocated to hold /// all of the fixed size frame objects. This is only valid after /// Prolog/Epilog code insertion has finalized the stack frame layout. uint64_t getStackSize() const { return StackSize; } /// Set the size of the stack. void setStackSize(uint64_t Size) { StackSize = Size; } /// Estimate and return the size of the stack frame. uint64_t estimateStackSize(const MachineFunction &MF) const; /// Return the correction for frame offsets. int getOffsetAdjustment() const { return OffsetAdjustment; } /// Set the correction for frame offsets. void setOffsetAdjustment(int Adj) { OffsetAdjustment = Adj; } /// Return the alignment in bytes that this function must be aligned to, /// which is greater than the default stack alignment provided by the target. Align getMaxAlign() const { return MaxAlignment; } /// Make sure the function is at least Align bytes aligned. void ensureMaxAlignment(Align Alignment); /// Return true if this function adjusts the stack -- e.g., /// when calling another function. This is only valid during and after /// prolog/epilog code insertion. bool adjustsStack() const { return AdjustsStack; } void setAdjustsStack(bool V) { AdjustsStack = V; } /// Return true if the current function has any function calls. bool hasCalls() const { return HasCalls; } void setHasCalls(bool V) { HasCalls = V; } /// Returns true if the function contains opaque dynamic stack adjustments. bool hasOpaqueSPAdjustment() const { return HasOpaqueSPAdjustment; } void setHasOpaqueSPAdjustment(bool B) { HasOpaqueSPAdjustment = B; } /// Returns true if the function contains operations which will lower down to /// instructions which manipulate the stack pointer. bool hasCopyImplyingStackAdjustment() const { return HasCopyImplyingStackAdjustment; } void setHasCopyImplyingStackAdjustment(bool B) { HasCopyImplyingStackAdjustment = B; } /// Returns true if the function calls the llvm.va_start intrinsic. bool hasVAStart() const { return HasVAStart; } void setHasVAStart(bool B) { HasVAStart = B; } /// Returns true if the function is variadic and contains a musttail call. bool hasMustTailInVarArgFunc() const { return HasMustTailInVarArgFunc; } void setHasMustTailInVarArgFunc(bool B) { HasMustTailInVarArgFunc = B; } /// Returns true if the function contains a tail call. bool hasTailCall() const { return HasTailCall; } void setHasTailCall(bool V = true) { HasTailCall = V; } /// Computes the maximum size of a callframe and the AdjustsStack property. /// This only works for targets defining /// TargetInstrInfo::getCallFrameSetupOpcode(), getCallFrameDestroyOpcode(), /// and getFrameSize(). /// This is usually computed by the prologue epilogue inserter but some /// targets may call this to compute it earlier. void computeMaxCallFrameSize(const MachineFunction &MF); /// Return the maximum size of a call frame that must be /// allocated for an outgoing function call. This is only available if /// CallFrameSetup/Destroy pseudo instructions are used by the target, and /// then only during or after prolog/epilog code insertion. /// unsigned getMaxCallFrameSize() const { // TODO: Enable this assert when targets are fixed. //assert(isMaxCallFrameSizeComputed() && "MaxCallFrameSize not computed yet"); if (!isMaxCallFrameSizeComputed()) return 0; return MaxCallFrameSize; } bool isMaxCallFrameSizeComputed() const { return MaxCallFrameSize != ~0u; } void setMaxCallFrameSize(unsigned S) { MaxCallFrameSize = S; } /// Returns how many bytes of callee-saved registers the target pushed in the /// prologue. Only used for debug info. unsigned getCVBytesOfCalleeSavedRegisters() const { return CVBytesOfCalleeSavedRegisters; } void setCVBytesOfCalleeSavedRegisters(unsigned S) { CVBytesOfCalleeSavedRegisters = S; } /// Create a new object at a fixed location on the stack. /// All fixed objects should be created before other objects are created for /// efficiency. By default, fixed objects are not pointed to by LLVM IR /// values. This returns an index with a negative value. int CreateFixedObject(uint64_t Size, int64_t SPOffset, bool IsImmutable, bool isAliased = false); /// Create a spill slot at a fixed location on the stack. /// Returns an index with a negative value. int CreateFixedSpillStackObject(uint64_t Size, int64_t SPOffset, bool IsImmutable = false); /// Returns true if the specified index corresponds to a fixed stack object. bool isFixedObjectIndex(int ObjectIdx) const { return ObjectIdx < 0 && (ObjectIdx >= -(int)NumFixedObjects); } /// Returns true if the specified index corresponds /// to an object that might be pointed to by an LLVM IR value. bool isAliasedObjectIndex(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx+NumFixedObjects].isAliased; } /// Returns true if the specified index corresponds to an immutable object. bool isImmutableObjectIndex(int ObjectIdx) const { // Tail calling functions can clobber their function arguments. if (HasTailCall) return false; assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx+NumFixedObjects].isImmutable; } /// Marks the immutability of an object. void setIsImmutableObjectIndex(int ObjectIdx, bool IsImmutable) { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); Objects[ObjectIdx+NumFixedObjects].isImmutable = IsImmutable; } /// Returns true if the specified index corresponds to a spill slot. bool isSpillSlotObjectIndex(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx+NumFixedObjects].isSpillSlot; } bool isStatepointSpillSlotObjectIndex(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx+NumFixedObjects].isStatepointSpillSlot; } /// \see StackID uint8_t getStackID(int ObjectIdx) const { return Objects[ObjectIdx+NumFixedObjects].StackID; } /// \see StackID void setStackID(int ObjectIdx, uint8_t ID) { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); Objects[ObjectIdx+NumFixedObjects].StackID = ID; // If ID > 0, MaxAlignment may now be overly conservative. // If ID == 0, MaxAlignment will need to be updated separately. } /// Returns true if the specified index corresponds to a dead object. bool isDeadObjectIndex(int ObjectIdx) const { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx+NumFixedObjects].Size == ~0ULL; } /// Returns true if the specified index corresponds to a variable sized /// object. bool isVariableSizedObjectIndex(int ObjectIdx) const { assert(unsigned(ObjectIdx + NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); return Objects[ObjectIdx + NumFixedObjects].Size == 0; } void markAsStatepointSpillSlotObjectIndex(int ObjectIdx) { assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() && "Invalid Object Idx!"); Objects[ObjectIdx+NumFixedObjects].isStatepointSpillSlot = true; assert(isStatepointSpillSlotObjectIndex(ObjectIdx) && "inconsistent"); } /// Create a new statically sized stack object, returning /// a nonnegative identifier to represent it. int CreateStackObject(uint64_t Size, Align Alignment, bool isSpillSlot, const AllocaInst *Alloca = nullptr, uint8_t ID = 0); /// Create a new statically sized stack object that represents a spill slot, /// returning a nonnegative identifier to represent it. int CreateSpillStackObject(uint64_t Size, Align Alignment); /// Remove or mark dead a statically sized stack object. void RemoveStackObject(int ObjectIdx) { // Mark it dead. Objects[ObjectIdx+NumFixedObjects].Size = ~0ULL; } /// Notify the MachineFrameInfo object that a variable sized object has been /// created. This must be created whenever a variable sized object is /// created, whether or not the index returned is actually used. int CreateVariableSizedObject(Align Alignment, const AllocaInst *Alloca); /// Returns a reference to call saved info vector for the current function. const std::vector &getCalleeSavedInfo() const { return CSInfo; } /// \copydoc getCalleeSavedInfo() std::vector &getCalleeSavedInfo() { return CSInfo; } /// Used by prolog/epilog inserter to set the function's callee saved /// information. void setCalleeSavedInfo(std::vector CSI) { CSInfo = std::move(CSI); } /// Has the callee saved info been calculated yet? bool isCalleeSavedInfoValid() const { return CSIValid; } void setCalleeSavedInfoValid(bool v) { CSIValid = v; } MachineBasicBlock *getSavePoint() const { return Save; } void setSavePoint(MachineBasicBlock *NewSave) { Save = NewSave; } MachineBasicBlock *getRestorePoint() const { return Restore; } void setRestorePoint(MachineBasicBlock *NewRestore) { Restore = NewRestore; } /// Return a set of physical registers that are pristine. /// /// Pristine registers hold a value that is useless to the current function, /// but that must be preserved - they are callee saved registers that are not /// saved. /// /// Before the PrologueEpilogueInserter has placed the CSR spill code, this /// method always returns an empty set. BitVector getPristineRegs(const MachineFunction &MF) const; /// Used by the MachineFunction printer to print information about /// stack objects. Implemented in MachineFunction.cpp. void print(const MachineFunction &MF, raw_ostream &OS) const; /// dump - Print the function to stderr. void dump(const MachineFunction &MF) const; }; } // End llvm namespace #endif #ifdef __GNUC__ #pragma GCC diagnostic pop #endif