class MachineFunction;
class MachineBasicBlock;
class TargetFrameLowering;
+class TargetMachine;
class BitVector;
class Value;
class AllocaInst;
// 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;
-
/// Alloca - If this stack object is originated from an Alloca instruction
/// this value saves the original IR allocation. Can be NULL.
const AllocaInst *Alloca;
// block and doesn't need additional handling for allocation beyond that.
bool PreAllocated;
+ // 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;
+
StackObject(uint64_t Sz, unsigned Al, int64_t SP, bool IM,
- bool isSS, bool NSP, const AllocaInst *Val)
+ bool isSS, const AllocaInst *Val, bool A)
: SPOffset(SP), Size(Sz), Alignment(Al), isImmutable(IM),
- isSpillSlot(isSS), MayNeedSP(NSP), Alloca(Val), PreAllocated(false) {}
+ isSpillSlot(isSS), Alloca(Val), PreAllocated(false), isAliased(A) {}
};
+ /// StackAlignment - The alignment of the stack.
+ unsigned StackAlignment;
+
+ /// StackRealignable - Can the stack be realigned.
+ bool StackRealignable;
+
/// Objects - The list of stack objects allocated...
///
std::vector<StackObject> Objects;
/// to builtin \@llvm.returnaddress.
bool ReturnAddressTaken;
+ /// HasStackMap - This boolean keeps track of whether there is a call
+ /// to builtin \@llvm.experimental.stackmap.
+ bool HasStackMap;
+
+ /// HasPatchPoint - This boolean keeps track of whether there is a call
+ /// to builtin \@llvm.experimental.patchpoint.
+ bool HasPatchPoint;
+
/// 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
/// 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;
/// just allocate them normally.
bool UseLocalStackAllocationBlock;
+ /// Whether the "realign-stack" option is on.
+ bool RealignOption;
+
+ /// True if the function includes inline assembly that adjusts the stack
+ /// pointer.
+ bool HasInlineAsmWithSPAdjust;
+
+ /// True if the function contains a call to the llvm.vastart intrinsic.
+ bool HasVAStart;
+
+ /// True if this is a varargs function that contains a musttail call.
+ bool HasMustTailInVarArgFunc;
+
+ /// 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;
+
+ /// Not null, if shrink-wrapping found a better place for the prologue.
+ MachineBasicBlock *Save;
+ /// Not null, if shrink-wrapping found a better place for the epilogue.
+ MachineBasicBlock *Restore;
+
public:
- explicit MachineFrameInfo(const TargetFrameLowering &tfi) : TFI(tfi) {
+ explicit MachineFrameInfo(unsigned StackAlign, bool isStackRealign,
+ bool RealignOpt)
+ : StackAlignment(StackAlign), StackRealignable(isStackRealign),
+ RealignOption(RealignOpt) {
StackSize = NumFixedObjects = OffsetAdjustment = MaxAlignment = 0;
HasVarSizedObjects = false;
FrameAddressTaken = false;
ReturnAddressTaken = false;
+ HasStackMap = false;
+ HasPatchPoint = false;
AdjustsStack = false;
HasCalls = false;
StackProtectorIdx = -1;
LocalFrameSize = 0;
LocalFrameMaxAlign = 0;
UseLocalStackAllocationBlock = false;
+ HasInlineAsmWithSPAdjust = false;
+ HasVAStart = false;
+ HasMustTailInVarArgFunc = false;
+ Save = nullptr;
+ Restore = nullptr;
+ HasTailCall = false;
}
/// hasStackObjects - Return true if there are any stack objects in this
bool isReturnAddressTaken() const { return ReturnAddressTaken; }
void setReturnAddressIsTaken(bool s) { ReturnAddressTaken = s; }
+ /// hasStackMap - 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; }
+
+ /// hasPatchPoint - 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; }
+
/// getObjectIndexBegin - Return the minimum frame object index.
///
int getObjectIndexBegin() const { return -NumFixedObjects; }
return Objects[ObjectIdx+NumFixedObjects].Alloca;
}
- /// 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.
///
///
void setStackSize(uint64_t Size) { StackSize = Size; }
+ /// Estimate and return the size of the stack frame.
+ unsigned estimateStackSize(const MachineFunction &MF) const;
+
/// getOffsetAdjustment - Return the correction for frame offsets.
///
int getOffsetAdjustment() const { return OffsetAdjustment; }
bool hasCalls() const { return HasCalls; }
void setHasCalls(bool V) { HasCalls = V; }
+ /// Returns true if the function contains any stack-adjusting inline assembly.
+ bool hasInlineAsmWithSPAdjust() const { return HasInlineAsmWithSPAdjust; }
+ void setHasInlineAsmWithSPAdjust(bool B) { HasInlineAsmWithSPAdjust = 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() { HasTailCall = true; }
+
/// getMaxCallFrameSize - 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
/// CreateFixedObject - 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 immutable. This returns an
- /// index with a negative value.
+ /// 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 Immutable);
+ int CreateFixedObject(uint64_t Size, int64_t SPOffset, bool Immutable,
+ bool isAliased = false);
+ /// CreateFixedSpillStackObject - 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);
/// isFixedObjectIndex - Returns true if the specified index corresponds to a
/// fixed stack object.
return ObjectIdx < 0 && (ObjectIdx >= -(int)NumFixedObjects);
}
+ /// isAliasedObjectIndex - 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;
+ }
+
/// isImmutableObjectIndex - 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;
/// a nonnegative identifier to represent it.
///
int CreateStackObject(uint64_t Size, unsigned Alignment, bool isSS,
- bool MayNeedSP = false, const AllocaInst *Alloca = 0);
+ const AllocaInst *Alloca = nullptr);
/// CreateSpillStackObject - Create a new statically sized stack object that
/// represents a spill slot, returning a nonnegative identifier to represent
/// variable sized object is created, whether or not the index returned is
/// actually used.
///
- int CreateVariableSizedObject(unsigned Alignment);
+ int CreateVariableSizedObject(unsigned Alignment, const AllocaInst *Alloca);
/// getCalleeSavedInfo - Returns a reference to call saved info vector for the
/// current function.
void setCalleeSavedInfoValid(bool v) { CSIValid = v; }
- /// getPristineRegs - Return a set of physical registers that are pristine on
- /// entry to the MBB.
+ 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 have not
- /// been saved yet.
+ /// 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 MachineBasicBlock *MBB) const;
+ BitVector getPristineRegs(const MachineFunction &MF) const;
/// print - Used by the MachineFunction printer to print information about
/// stack objects. Implemented in MachineFunction.cpp