// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
-
+//
+// The file defines the MachineFrameInfo class.
+//
+//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_MACHINEFRAMEINFO_H
#define LLVM_CODEGEN_MACHINEFRAMEINFO_H
+#include "llvm/ADT/SmallVector.h"
+//#include "llvm/ADT/IndexedMap.h"
+#include "llvm/Support/DataTypes.h"
+#include <cassert>
#include <vector>
namespace llvm {
+class raw_ostream;
class TargetData;
class TargetRegisterClass;
class Type;
-class MachineModuleInfo;
class MachineFunction;
+class MachineBasicBlock;
+class TargetFrameLowering;
+class BitVector;
/// The CalleeSavedInfo class tracks the information need to locate where a
-/// callee saved register in the current frame.
+/// callee saved register is in the current frame.
class CalleeSavedInfo {
-
-private:
unsigned Reg;
- const TargetRegisterClass *RegClass;
int FrameIdx;
-
+
public:
- CalleeSavedInfo(unsigned R, const TargetRegisterClass *RC, int FI = 0)
- : Reg(R)
- , RegClass(RC)
- , FrameIdx(FI)
- {}
-
+ explicit CalleeSavedInfo(unsigned R, int FI = 0)
+ : Reg(R), FrameIdx(FI) {}
+
// Accessors.
unsigned getReg() const { return Reg; }
- const TargetRegisterClass *getRegClass() const { return RegClass; }
int getFrameIdx() const { return FrameIdx; }
void setFrameIdx(int FI) { FrameIdx = FI; }
};
///
/// 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 positive
+/// 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.
// StackObject - Represent a single object allocated on the stack.
struct StackObject {
- // The size of this object on the stack. 0 means a variable sized object
+ // SPOffset - 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;
// Alignment - The required alignment of this stack slot.
unsigned Alignment;
- // SPOffset - 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;
-
- // isImmutable - If true, the value of the stack object does not change
- // in this function. By default, fixed objects are immutable unless marked
- // otherwise.
+ // isImmutable - 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;
- StackObject(uint64_t Sz, unsigned Al, int64_t SP, bool IM = false)
- : Size(Sz), Alignment(Al), SPOffset(SP), isImmutable(IM) {}
+ // isSpillSlot - If true the stack object is used as spill slot. It
+ // cannot alias any other memory objects.
+ bool isSpillSlot;
+
+ // MayNeedSP - If true the stack object triggered the creation of the stack
+ // protector. We should allocate this object right after the stack
+ // protector.
+ bool MayNeedSP;
+
+ // PreAllocated - If true, the object was mapped into the local frame
+ // block and doesn't need additional handling for allocation beyond that.
+ bool PreAllocated;
+
+ StackObject(uint64_t Sz, unsigned Al, int64_t SP, bool IM,
+ bool isSS, bool NSP)
+ : SPOffset(SP), Size(Sz), Alignment(Al), isImmutable(IM),
+ isSpillSlot(isSS), MayNeedSP(NSP), PreAllocated(false) {}
};
/// Objects - The list of stack objects allocated...
///
bool HasVarSizedObjects;
+ /// FrameAddressTaken - This boolean keeps track of whether there is a call
+ /// to builtin \@llvm.frameaddress.
+ bool FrameAddressTaken;
+
+ /// ReturnAddressTaken - This boolean keeps track of whether there is a call
+ /// to builtin \@llvm.returnaddress.
+ bool ReturnAddressTaken;
+
/// StackSize - 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;
-
+
/// OffsetAdjustment - The amount that a frame offset needs to be adjusted to
- /// have the actual offset from the stack/frame pointer. The calculation is
- /// MFI->getObjectOffset(Index) + StackSize - TFI.getOffsetOfLocalArea() +
- /// OffsetAdjustment. If OffsetAdjustment is zero (default) then offsets are
- /// away from TOS. If OffsetAdjustment == StackSize then offsets are toward
- /// TOS.
+ /// 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::getFrameIndexOffset); when generating code, the
+ /// corresponding adjustments are performed directly.
int OffsetAdjustment;
-
- /// MaxAlignment - The prolog/epilog code inserter may process objects
+
+ /// MaxAlignment - 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
+ /// 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.
///
unsigned MaxAlignment;
- /// HasCalls - Set to true if this function has any function calls. This is
- /// only valid during and after prolog/epilog code insertion.
+ /// AdjustsStack - 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;
+
+ /// HasCalls - Set to true if this function has any function calls.
bool HasCalls;
+ /// StackProtectorIdx - The frame index for the stack protector.
+ int StackProtectorIdx;
+
/// MaxCallFrameSize - 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
/// insertion.
///
unsigned MaxCallFrameSize;
-
+
/// CSInfo - The prolog/epilog code inserter fills in this vector with each
/// callee saved register saved in the frame. Beyond its use by the prolog/
/// epilog code inserter, this data used for debug info and exception
/// handling.
std::vector<CalleeSavedInfo> CSInfo;
-
- /// MMI - This field is set (via setMachineModuleInfo) by a module info
- /// consumer (ex. DwarfWriter) to indicate that frame layout information
- /// should be acquired. Typically, it's the responsibility of the target's
- /// MRegisterInfo prologue/epilogue emitting code to inform MachineModuleInfo
- /// of frame layouts.
- MachineModuleInfo *MMI;
-
+
+ /// CSIValid - Has CSInfo been set yet?
+ bool CSIValid;
+
+ /// TargetFrameLowering - Target information about frame layout.
+ ///
+ const TargetFrameLowering &TFI;
+
+ /// LocalFrameObjects - References to frame indices which are mapped
+ /// into the local frame allocation block. <FrameIdx, LocalOffset>
+ SmallVector<std::pair<int, int64_t>, 32> LocalFrameObjects;
+
+ /// LocalFrameSize - Size of the pre-allocated local frame block.
+ int64_t LocalFrameSize;
+
+ /// Required alignment of the local object blob, which is the strictest
+ /// alignment of any object in it.
+ unsigned 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;
+
public:
- MachineFrameInfo() {
+ explicit MachineFrameInfo(const TargetFrameLowering &tfi) : TFI(tfi) {
StackSize = NumFixedObjects = OffsetAdjustment = MaxAlignment = 0;
HasVarSizedObjects = false;
+ FrameAddressTaken = false;
+ ReturnAddressTaken = false;
+ AdjustsStack = false;
HasCalls = false;
+ StackProtectorIdx = -1;
MaxCallFrameSize = 0;
- MMI = 0;
+ CSIValid = false;
+ LocalFrameSize = 0;
+ LocalFrameMaxAlign = 0;
+ UseLocalStackAllocationBlock = false;
}
/// hasStackObjects - Return true if there are any stack objects in this
///
bool hasVarSizedObjects() const { return HasVarSizedObjects; }
- /// getObjectIndexBegin - Return the minimum frame object index...
+ /// getStackProtectorIndex/setStackProtectorIndex - Return the index for the
+ /// stack protector object.
+ ///
+ int getStackProtectorIndex() const { return StackProtectorIdx; }
+ void setStackProtectorIndex(int I) { StackProtectorIdx = I; }
+
+ /// isFrameAddressTaken - 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; }
+
+ /// isReturnAddressTaken - 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; }
+
+ /// getObjectIndexBegin - Return the minimum frame object index.
///
int getObjectIndexBegin() const { return -NumFixedObjects; }
- /// getObjectIndexEnd - Return one past the maximum frame object index...
+ /// getObjectIndexEnd - Return one past the maximum frame object index.
///
- int getObjectIndexEnd() const { return Objects.size()-NumFixedObjects; }
+ int getObjectIndexEnd() const { return (int)Objects.size()-NumFixedObjects; }
+
+ /// getNumFixedObjects - Return the number of fixed objects.
+ unsigned getNumFixedObjects() const { return NumFixedObjects; }
- /// getObjectSize - Return the size of the specified object
+ /// getNumObjects - Return the number of objects.
+ ///
+ unsigned getNumObjects() const { return Objects.size(); }
+
+ /// mapLocalFrameObject - Map a frame index into the local object block
+ void mapLocalFrameObject(int ObjectIndex, int64_t Offset) {
+ LocalFrameObjects.push_back(std::pair<int, int64_t>(ObjectIndex, Offset));
+ Objects[ObjectIndex + NumFixedObjects].PreAllocated = true;
+ }
+
+ /// getLocalFrameObjectMap - Get the local offset mapping for a for an object
+ std::pair<int, int64_t> getLocalFrameObjectMap(int i) {
+ assert (i >= 0 && (unsigned)i < LocalFrameObjects.size() &&
+ "Invalid local object reference!");
+ return LocalFrameObjects[i];
+ }
+
+ /// getLocalFrameObjectCount - Return the number of objects allocated into
+ /// the local object block.
+ int64_t getLocalFrameObjectCount() { return LocalFrameObjects.size(); }
+
+ /// setLocalFrameSize - Set the size of the local object blob.
+ void setLocalFrameSize(int64_t sz) { LocalFrameSize = sz; }
+
+ /// getLocalFrameSize - Get the size of the local object blob.
+ int64_t getLocalFrameSize() const { return LocalFrameSize; }
+
+ /// setLocalFrameMaxAlign - Required alignment of the local object blob,
+ /// which is the strictest alignment of any object in it.
+ void setLocalFrameMaxAlign(unsigned Align) { LocalFrameMaxAlign = Align; }
+
+ /// getLocalFrameMaxAlign - Return the required alignment of the local
+ /// object blob.
+ unsigned getLocalFrameMaxAlign() const { return LocalFrameMaxAlign; }
+
+ /// getUseLocalStackAllocationBlock - Get whether the local allocation blob
+ /// should be allocated together or let PEI allocate the locals in it
+ /// directly.
+ bool getUseLocalStackAllocationBlock() {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;
+ }
+
+ /// isObjectPreAllocated - 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;
+ }
+
+ /// getObjectSize - Return the size of the specified object.
///
int64_t getObjectSize(int ObjectIdx) const {
- assert(ObjectIdx+NumFixedObjects < Objects.size() && "Invalid Object Idx!");
+ assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() &&
+ "Invalid Object Idx!");
return Objects[ObjectIdx+NumFixedObjects].Size;
}
- /// getObjectAlignment - Return the alignment of the specified stack object...
- int getObjectAlignment(int ObjectIdx) const {
- assert(ObjectIdx+NumFixedObjects < Objects.size() && "Invalid Object Idx!");
+ /// setObjectSize - 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;
+ }
+
+ /// getObjectAlignment - Return the alignment of the specified stack object.
+ unsigned getObjectAlignment(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, unsigned Align) {
+ assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() &&
+ "Invalid Object Idx!");
+ Objects[ObjectIdx+NumFixedObjects].Alignment = Align;
+ MaxAlignment = std::max(MaxAlignment, Align);
+ }
+
+ /// NeedsStackProtector - Returns true if the object may need stack
+ /// protectors.
+ bool MayNeedStackProtector(int ObjectIdx) const {
+ assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() &&
+ "Invalid Object Idx!");
+ return Objects[ObjectIdx+NumFixedObjects].MayNeedSP;
+ }
+
/// getObjectOffset - Return the assigned stack offset of the specified object
/// from the incoming stack pointer.
///
int64_t getObjectOffset(int ObjectIdx) const {
- assert(ObjectIdx+NumFixedObjects < Objects.size() && "Invalid Object Idx!");
+ assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() &&
+ "Invalid Object Idx!");
+ assert(!isDeadObjectIndex(ObjectIdx) &&
+ "Getting frame offset for a dead object?");
return Objects[ObjectIdx+NumFixedObjects].SPOffset;
}
/// offset is relative to the stack pointer on entry to the function.
///
void setObjectOffset(int ObjectIdx, int64_t SPOffset) {
- assert(ObjectIdx+NumFixedObjects < Objects.size() && "Invalid Object Idx!");
+ assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() &&
+ "Invalid Object Idx!");
+ assert(!isDeadObjectIndex(ObjectIdx) &&
+ "Setting frame offset for a dead object?");
Objects[ObjectIdx+NumFixedObjects].SPOffset = SPOffset;
}
/// setStackSize - Set the size of the stack...
///
void setStackSize(uint64_t Size) { StackSize = Size; }
-
+
/// getOffsetAdjustment - Return the correction for frame offsets.
///
int getOffsetAdjustment() const { return OffsetAdjustment; }
-
+
/// setOffsetAdjustment - Set the correction for frame offsets.
///
void setOffsetAdjustment(int Adj) { OffsetAdjustment = Adj; }
- /// getMaxAlignment - Return the alignment in bytes that this function must be
- /// aligned to, which is greater than the default stack alignment provided by
+ /// getMaxAlignment - Return the alignment in bytes that this function must be
+ /// aligned to, which is greater than the default stack alignment provided by
/// the target.
///
unsigned getMaxAlignment() const { return MaxAlignment; }
-
+
/// setMaxAlignment - Set the preferred alignment.
///
void setMaxAlignment(unsigned Align) { MaxAlignment = Align; }
-
- /// hasCalls - Return true if the current function has no function calls.
- /// This is only valid during or after prolog/epilog code emission.
- ///
+
+ /// AdjustsStack - 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; }
+
+ /// hasCalls - Return true if the current function has any function calls.
bool hasCalls() const { return HasCalls; }
void setHasCalls(bool V) { HasCalls = V; }
/// efficiency. By default, fixed objects are immutable. This returns an
/// index with a negative value.
///
- int CreateFixedObject(uint64_t Size, int64_t SPOffset,
- bool Immutable = true) {
- assert(Size != 0 && "Cannot allocate zero size fixed stack objects!");
- Objects.insert(Objects.begin(), StackObject(Size, 1, SPOffset, Immutable));
- return -++NumFixedObjects;
- }
+ int CreateFixedObject(uint64_t Size, int64_t SPOffset, bool Immutable);
+
/// isFixedObjectIndex - Returns true if the specified index corresponds to a
/// fixed stack object.
/// isImmutableObjectIndex - Returns true if the specified index corresponds
/// to an immutable object.
bool isImmutableObjectIndex(int ObjectIdx) const {
+ assert(unsigned(ObjectIdx+NumFixedObjects) < Objects.size() &&
+ "Invalid Object Idx!");
return Objects[ObjectIdx+NumFixedObjects].isImmutable;
}
+ /// isSpillSlotObjectIndex - 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;;
+ }
+
+ /// isDeadObjectIndex - 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;
+ }
+
/// CreateStackObject - Create a new statically sized stack object, returning
- /// a postive identifier to represent it.
+ /// a nonnegative identifier to represent it.
///
- int CreateStackObject(uint64_t Size, unsigned Alignment) {
- // Keep track of the maximum alignment.
- if (MaxAlignment < Alignment) MaxAlignment = Alignment;
-
+ int CreateStackObject(uint64_t Size, unsigned Alignment, bool isSS,
+ bool MayNeedSP = false) {
assert(Size != 0 && "Cannot allocate zero size stack objects!");
- Objects.push_back(StackObject(Size, Alignment, -1));
- return Objects.size()-NumFixedObjects-1;
+ Objects.push_back(StackObject(Size, Alignment, 0, false, isSS, MayNeedSP));
+ int Index = (int)Objects.size() - NumFixedObjects - 1;
+ assert(Index >= 0 && "Bad frame index!");
+ MaxAlignment = std::max(MaxAlignment, Alignment);
+ return Index;
+ }
+
+ /// CreateSpillStackObject - Create a new statically sized stack object that
+ /// represents a spill slot, returning a nonnegative identifier to represent
+ /// it.
+ ///
+ int CreateSpillStackObject(uint64_t Size, unsigned Alignment) {
+ CreateStackObject(Size, Alignment, true, false);
+ int Index = (int)Objects.size() - NumFixedObjects - 1;
+ MaxAlignment = std::max(MaxAlignment, Alignment);
+ return Index;
+ }
+
+ /// RemoveStackObject - Remove or mark dead a statically sized stack object.
+ ///
+ void RemoveStackObject(int ObjectIdx) {
+ // Mark it dead.
+ Objects[ObjectIdx+NumFixedObjects].Size = ~0ULL;
}
/// CreateVariableSizedObject - Notify the MachineFrameInfo object that a
/// variable sized object is created, whether or not the index returned is
/// actually used.
///
- int CreateVariableSizedObject() {
+ int CreateVariableSizedObject(unsigned Alignment) {
HasVarSizedObjects = true;
- if (MaxAlignment < 1) MaxAlignment = 1;
- Objects.push_back(StackObject(0, 1, -1));
- return Objects.size()-NumFixedObjects-1;
+ Objects.push_back(StackObject(0, Alignment, 0, false, false, true));
+ MaxAlignment = std::max(MaxAlignment, Alignment);
+ return (int)Objects.size()-NumFixedObjects-1;
}
-
+
/// getCalleeSavedInfo - Returns a reference to call saved info vector for the
/// current function.
const std::vector<CalleeSavedInfo> &getCalleeSavedInfo() const {
/// setCalleeSavedInfo - Used by prolog/epilog inserter to set the function's
/// callee saved information.
- void setCalleeSavedInfo(const std::vector<CalleeSavedInfo> &CSI) {
+ void setCalleeSavedInfo(const std::vector<CalleeSavedInfo> &CSI) {
CSInfo = CSI;
}
- /// getMachineModuleInfo - Used by a prologue/epilogue emitter (MRegisterInfo)
- /// to provide frame layout information.
- MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
+ /// isCalleeSavedInfoValid - Has the callee saved info been calculated yet?
+ bool isCalleeSavedInfoValid() const { return CSIValid; }
+
+ void setCalleeSavedInfoValid(bool v) { CSIValid = v; }
- /// setMachineModuleInfo - Used by a meta info consumer (DwarfWriter) to
- /// indicate that frame layout information should be gathered.
- void setMachineModuleInfo(MachineModuleInfo *mmi) { MMI = mmi; }
+ /// getPristineRegs - Return a set of physical registers that are pristine on
+ /// entry to the MBB.
+ ///
+ /// Pristine registers hold a value that is useless to the current function,
+ /// but that must be preserved - they are callee saved registers that have not
+ /// been saved yet.
+ ///
+ /// Before the PrologueEpilogueInserter has placed the CSR spill code, this
+ /// method always returns an empty set.
+ BitVector getPristineRegs(const MachineBasicBlock *MBB) const;
/// print - Used by the MachineFunction printer to print information about
- /// stack objects. Implemented in MachineFunction.cpp
+ /// stack objects. Implemented in MachineFunction.cpp
///
- void print(const MachineFunction &MF, std::ostream &OS) const;
+ void print(const MachineFunction &MF, raw_ostream &OS) const;
- /// dump - Call print(MF, std::cerr) to be called from the debugger.
+ /// dump - Print the function to stderr.
void dump(const MachineFunction &MF) const;
};