mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-26 21:32:10 +00:00
5b00ceaeea
Dynamic linking on PPC64 has had problems since we had to move the top-down hazard-detection logic post-ra. For dynamic linking to work there needs to be a nop placed after every call. It turns out that it is really hard to guarantee that nothing will be placed in between the call (bl) and the nop during post-ra scheduling. Previous attempts at fixing this by placing logic inside the hazard detector only partially worked. This is now fixed in a different way: call+nop codegen-only instructions. As far as CodeGen is concerned the pair is now a single instruction and cannot be split. This solution works much better than previous attempts. The scoreboard hazard detector is also renamed to be more generic, there is currently no cpu-specific logic in it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153816 91177308-0d34-0410-b5e6-96231b3b80d8
92 lines
3.3 KiB
C++
92 lines
3.3 KiB
C++
//===-- PPCHazardRecognizers.h - PowerPC Hazard Recognizers -----*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file defines hazard recognizers for scheduling on PowerPC processors.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef PPCHAZRECS_H
|
|
#define PPCHAZRECS_H
|
|
|
|
#include "PPCInstrInfo.h"
|
|
#include "llvm/CodeGen/ScheduleHazardRecognizer.h"
|
|
#include "llvm/CodeGen/ScoreboardHazardRecognizer.h"
|
|
#include "llvm/CodeGen/SelectionDAGNodes.h"
|
|
|
|
namespace llvm {
|
|
|
|
/// PPCScoreboardHazardRecognizer - This class implements a scoreboard-based
|
|
/// hazard recognizer for generic PPC processors.
|
|
class PPCScoreboardHazardRecognizer : public ScoreboardHazardRecognizer {
|
|
const ScheduleDAG *DAG;
|
|
public:
|
|
PPCScoreboardHazardRecognizer(const InstrItineraryData *ItinData,
|
|
const ScheduleDAG *DAG_) :
|
|
ScoreboardHazardRecognizer(ItinData, DAG_), DAG(DAG_) {}
|
|
|
|
virtual HazardType getHazardType(SUnit *SU, int Stalls);
|
|
virtual void EmitInstruction(SUnit *SU);
|
|
virtual void AdvanceCycle();
|
|
virtual void Reset();
|
|
};
|
|
|
|
/// PPCHazardRecognizer970 - This class defines a finite state automata that
|
|
/// models the dispatch logic on the PowerPC 970 (aka G5) processor. This
|
|
/// promotes good dispatch group formation and implements noop insertion to
|
|
/// avoid structural hazards that cause significant performance penalties (e.g.
|
|
/// setting the CTR register then branching through it within a dispatch group),
|
|
/// or storing then loading from the same address within a dispatch group.
|
|
class PPCHazardRecognizer970 : public ScheduleHazardRecognizer {
|
|
const TargetInstrInfo &TII;
|
|
|
|
unsigned NumIssued; // Number of insts issued, including advanced cycles.
|
|
|
|
// Various things that can cause a structural hazard.
|
|
|
|
// HasCTRSet - If the CTR register is set in this group, disallow BCTRL.
|
|
bool HasCTRSet;
|
|
|
|
// StoredPtr - Keep track of the address of any store. If we see a load from
|
|
// the same address (or one that aliases it), disallow the store. We can have
|
|
// up to four stores in one dispatch group, hence we track up to 4.
|
|
//
|
|
// This is null if we haven't seen a store yet. We keep track of both
|
|
// operands of the store here, since we support [r+r] and [r+i] addressing.
|
|
const Value *StoreValue[4];
|
|
int64_t StoreOffset[4];
|
|
uint64_t StoreSize[4];
|
|
unsigned NumStores;
|
|
|
|
public:
|
|
PPCHazardRecognizer970(const TargetInstrInfo &TII);
|
|
virtual HazardType getHazardType(SUnit *SU, int Stalls);
|
|
virtual void EmitInstruction(SUnit *SU);
|
|
virtual void AdvanceCycle();
|
|
virtual void Reset();
|
|
|
|
private:
|
|
/// EndDispatchGroup - Called when we are finishing a new dispatch group.
|
|
///
|
|
void EndDispatchGroup();
|
|
|
|
/// GetInstrType - Classify the specified powerpc opcode according to its
|
|
/// pipeline.
|
|
PPCII::PPC970_Unit GetInstrType(unsigned Opcode,
|
|
bool &isFirst, bool &isSingle,bool &isCracked,
|
|
bool &isLoad, bool &isStore);
|
|
|
|
bool isLoadOfStoredAddress(uint64_t LoadSize, int64_t LoadOffset,
|
|
const Value *LoadValue) const;
|
|
};
|
|
|
|
} // end namespace llvm
|
|
|
|
#endif
|
|
|