#ifndef LLVM_TARGET_TARGETREGISTERINFO_H
#define LLVM_TARGET_TARGETREGISTERINFO_H
-#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/ADT/ArrayRef.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/ValueTypes.h"
-#include "llvm/ADT/ArrayRef.h"
-#include "llvm/CallingConv.h"
+#include "llvm/IR/CallingConv.h"
+#include "llvm/MC/MCRegisterInfo.h"
#include <cassert>
#include <functional>
class MachineFunction;
class RegScavenger;
template<class T> class SmallVectorImpl;
+class VirtRegMap;
class raw_ostream;
class TargetRegisterClass {
const unsigned *SubRegIndexLaneMasks;
regclass_iterator RegClassBegin, RegClassEnd; // List of regclasses
+ unsigned CoveringLanes;
protected:
TargetRegisterInfo(const TargetRegisterInfoDesc *ID,
regclass_iterator RegClassBegin,
regclass_iterator RegClassEnd,
const char *const *SRINames,
- const unsigned *SRILaneMasks);
+ const unsigned *SRILaneMasks,
+ unsigned CoveringLanes);
virtual ~TargetRegisterInfo();
public:
return SubRegIndexLaneMasks[SubIdx];
}
+ /// The lane masks returned by getSubRegIndexLaneMask() above can only be
+ /// used to determine if sub-registers overlap - they can't be used to
+ /// determine if a set of sub-registers completely cover another
+ /// sub-register.
+ ///
+ /// The X86 general purpose registers have two lanes corresponding to the
+ /// sub_8bit and sub_8bit_hi sub-registers. Both sub_32bit and sub_16bit have
+ /// lane masks '3', but the sub_16bit sub-register doesn't fully cover the
+ /// sub_32bit sub-register.
+ ///
+ /// On the other hand, the ARM NEON lanes fully cover their registers: The
+ /// dsub_0 sub-register is completely covered by the ssub_0 and ssub_1 lanes.
+ /// This is related to the CoveredBySubRegs property on register definitions.
+ ///
+ /// This function returns a bit mask of lanes that completely cover their
+ /// sub-registers. More precisely, given:
+ ///
+ /// Covering = getCoveringLanes();
+ /// MaskA = getSubRegIndexLaneMask(SubA);
+ /// MaskB = getSubRegIndexLaneMask(SubB);
+ ///
+ /// If (MaskA & ~(MaskB & Covering)) == 0, then SubA is completely covered by
+ /// SubB.
+ unsigned getCoveringLanes() const { return CoveringLanes; }
+
/// regsOverlap - Returns true if the two registers are equal or alias each
/// other. The registers may be virtual register.
bool regsOverlap(unsigned regA, unsigned regB) const {
return false;
}
- /// isSubRegister - Returns true if regB is a sub-register of regA.
- ///
- bool isSubRegister(unsigned regA, unsigned regB) const {
- return isSuperRegister(regB, regA);
- }
-
- /// isSuperRegister - Returns true if regB is a super-register of regA.
- ///
- bool isSuperRegister(unsigned RegA, unsigned RegB) const {
- for (MCSuperRegIterator I(RegA, this); I.isValid(); ++I)
- if (*I == RegB)
- return true;
- return false;
- }
-
/// getCalleeSavedRegs - Return a null-terminated list of all of the
/// callee saved registers on this target. The register should be in the
/// order of desired callee-save stack frame offset. The first register is
return 0;
}
-// Get the weight in units of pressure for this register class.
+ /// Get the weight in units of pressure for this register class.
virtual const RegClassWeight &getRegClassWeight(
const TargetRegisterClass *RC) const = 0;
+ /// Get the weight in units of pressure for this register unit.
+ virtual unsigned getRegUnitWeight(unsigned RegUnit) const = 0;
+
/// Get the number of dimensions of register pressure.
virtual unsigned getNumRegPressureSets() const = 0;
virtual const int *getRegClassPressureSets(
const TargetRegisterClass *RC) const = 0;
- /// getRawAllocationOrder - Returns the register allocation order for a
- /// specified register class with a target-dependent hint. The returned list
- /// may contain reserved registers that cannot be allocated.
- ///
- /// Register allocators need only call this function to resolve
- /// target-dependent hints, but it should work without hinting as well.
- virtual ArrayRef<MCPhysReg>
- getRawAllocationOrder(const TargetRegisterClass *RC,
- unsigned HintType, unsigned HintReg,
- const MachineFunction &MF) const {
- return RC->getRawAllocationOrder(MF);
- }
-
- /// ResolveRegAllocHint - Resolves the specified register allocation hint
- /// to a physical register. Returns the physical register if it is successful.
- virtual unsigned ResolveRegAllocHint(unsigned Type, unsigned Reg,
- const MachineFunction &MF) const {
- if (Type == 0 && Reg && isPhysicalRegister(Reg))
- return Reg;
- return 0;
- }
+ /// Get the dimensions of register pressure impacted by this register unit.
+ /// Returns a -1 terminated array of pressure set IDs.
+ virtual const int *getRegUnitPressureSets(unsigned RegUnit) const = 0;
+
+ /// Get a list of 'hint' registers that the register allocator should try
+ /// first when allocating a physical register for the virtual register
+ /// VirtReg. These registers are effectively moved to the front of the
+ /// allocation order.
+ ///
+ /// The Order argument is the allocation order for VirtReg's register class
+ /// as returned from RegisterClassInfo::getOrder(). The hint registers must
+ /// come from Order, and they must not be reserved.
+ ///
+ /// The default implementation of this function can resolve
+ /// target-independent hints provided to MRI::setRegAllocationHint with
+ /// HintType == 0. Targets that override this function should defer to the
+ /// default implementation if they have no reason to change the allocation
+ /// order for VirtReg. There may be target-independent hints.
+ virtual void getRegAllocationHints(unsigned VirtReg,
+ ArrayRef<MCPhysReg> Order,
+ SmallVectorImpl<MCPhysReg> &Hints,
+ const MachineFunction &MF,
+ const VirtRegMap *VRM = 0) const;
/// avoidWriteAfterWrite - Return true if the register allocator should avoid
/// writing a register from RC in two consecutive instructions.
// Do nothing.
}
+ /// Allow the target to reverse allocation order of local live ranges. This
+ /// will generally allocate shorter local live ranges first. For targets with
+ /// many registers, this could reduce regalloc compile time by a large
+ /// factor. It is disabled by default for three reasons:
+ /// (1) Top-down allocation is simpler and easier to debug for targets that
+ /// don't benefit from reversing the order.
+ /// (2) Bottom-up allocation could result in poor evicition decisions on some
+ /// targets affecting the performance of compiled code.
+ /// (3) Bottom-up allocation is no longer guaranteed to optimally color.
+ virtual bool reverseLocalAssignment() const { return false; }
+
+ /// Allow the target to override register assignment heuristics based on the
+ /// live range size. If this returns false, then local live ranges are always
+ /// assigned in order regardless of their size. This is a temporary hook for
+ /// debugging downstream codegen failures exposed by regalloc.
+ virtual bool mayOverrideLocalAssignment() const { return true; }
+
+ /// Allow the target to override the cost of using a callee-saved register for
+ /// the first time. Default value of 0 means we will use a callee-saved
+ /// register if it is available.
+ virtual unsigned getCSRFirstUseCost() const { return 0; }
+
/// requiresRegisterScavenging - returns true if the target requires (and can
/// make use of) the register scavenger.
virtual bool requiresRegisterScavenging(const MachineFunction &MF) const {
llvm_unreachable("isFrameOffsetLegal does not exist on this target");
}
- /// eliminateCallFramePseudoInstr - This method is called during prolog/epilog
- /// code insertion to eliminate call frame setup and destroy pseudo
- /// instructions (but only if the Target is using them). It is responsible
- /// for eliminating these instructions, replacing them with concrete
- /// instructions. This method need only be implemented if using call frame
- /// setup/destroy pseudo instructions.
- ///
- virtual void
- eliminateCallFramePseudoInstr(MachineFunction &MF,
- MachineBasicBlock &MBB,
- MachineBasicBlock::iterator MI) const {
- llvm_unreachable("Call Frame Pseudo Instructions do not exist on this "
- "target!");
- }
-
/// saveScavengerRegister - Spill the register so it can be used by the
/// register scavenger. Return true if the register was spilled, false
/// referenced by the iterator contains an MO_FrameIndex operand which must be
/// eliminated by this method. This method may modify or replace the
/// specified instruction, as long as it keeps the iterator pointing at the
- /// finished product. SPAdj is the SP adjustment due to call frame setup
- /// instruction.
+ /// finished product. SPAdj is the SP adjustment due to call frame setup
+ /// instruction. FIOperandNum is the FI operand number.
virtual void eliminateFrameIndex(MachineBasicBlock::iterator MI,
- int SPAdj, RegScavenger *RS=NULL) const = 0;
+ int SPAdj, unsigned FIOperandNum,
+ RegScavenger *RS = NULL) const = 0;
//===--------------------------------------------------------------------===//
/// Debug information queries.
/// Usage: OS << PrintRegUnit(Unit, TRI) << '\n';
///
class PrintRegUnit {
+protected:
const TargetRegisterInfo *TRI;
unsigned Unit;
public:
return OS;
}
+/// PrintVRegOrUnit - It is often convenient to track virtual registers and
+/// physical register units in the same list.
+class PrintVRegOrUnit : protected PrintRegUnit {
+public:
+ PrintVRegOrUnit(unsigned VRegOrUnit, const TargetRegisterInfo *tri)
+ : PrintRegUnit(VRegOrUnit, tri) {}
+ void print(raw_ostream&) const;
+};
+
+static inline raw_ostream &operator<<(raw_ostream &OS,
+ const PrintVRegOrUnit &PR) {
+ PR.print(OS);
+ return OS;
+}
+
} // End llvm namespace
#endif