// 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, const AllocaInst *Val)
+ bool isSS, const AllocaInst *Val, bool A)
: SPOffset(SP), Size(Sz), Alignment(Al), isImmutable(IM),
- isSpillSlot(isSS), Alloca(Val), PreAllocated(false) {}
+ isSpillSlot(isSS), Alloca(Val), PreAllocated(false), isAliased(A) {}
};
- const TargetMachine &TM;
+ /// StackAlignment - The alignment of the stack.
+ unsigned StackAlignment;
+
+ /// StackRealignable - Can the stack be realigned.
+ bool StackRealignable;
/// Objects - The list of stack objects allocated...
///
/// pointer.
bool HasInlineAsmWithSPAdjust;
- const TargetFrameLowering *getFrameLowering() const;
+ /// 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 TargetMachine &TM, bool RealignOpt)
- : TM(TM), RealignOption(RealignOpt) {
+ explicit MachineFrameInfo(unsigned StackAlign, bool isStackRealign,
+ bool RealignOpt)
+ : StackAlignment(StackAlign), StackRealignable(isStackRealign),
+ RealignOption(RealignOpt) {
StackSize = NumFixedObjects = OffsetAdjustment = MaxAlignment = 0;
HasVarSizedObjects = false;
FrameAddressTaken = false;
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 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,
- 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
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
projects / oota-llvm.git / blobdiff