blob: df47f984d57817bdd75e1b21eff31b9eb1c07325 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
|
//=- llvm/CodeGen/AntiDepBreaker.h - Anti-Dependence Breaking -*- C++ -*-=//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the AntiDepBreaker class, which implements
// anti-dependence breaking heuristics for post-register-allocation scheduling.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_ANTIDEPBREAKER_H
#define LLVM_CODEGEN_ANTIDEPBREAKER_H
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/ScheduleDAG.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include <vector>
namespace llvm {
/// AntiDepBreaker - This class works into conjunction with the
/// post-RA scheduler to rename registers to break register
/// anti-dependencies.
class AntiDepBreaker {
public:
typedef std::vector<std::pair<MachineInstr *, MachineInstr *> >
DbgValueVector;
virtual ~AntiDepBreaker();
/// Start - Initialize anti-dep breaking for a new basic block.
virtual void StartBlock(MachineBasicBlock *BB) =0;
/// BreakAntiDependencies - Identifiy anti-dependencies within a
/// basic-block region and break them by renaming registers. Return
/// the number of anti-dependencies broken.
///
virtual unsigned BreakAntiDependencies(const std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator Begin,
MachineBasicBlock::iterator End,
unsigned InsertPosIndex,
DbgValueVector &DbgValues) = 0;
/// Observe - Update liveness information to account for the current
/// instruction, which will not be scheduled.
///
virtual void Observe(MachineInstr *MI, unsigned Count,
unsigned InsertPosIndex) =0;
/// Finish - Finish anti-dep breaking for a basic block.
virtual void FinishBlock() =0;
/// UpdateDbgValue - Update DBG_VALUE if dependency breaker is updating
/// other machine instruction to use NewReg.
void UpdateDbgValue(MachineInstr *MI, unsigned OldReg, unsigned NewReg) {
assert (MI->isDebugValue() && "MI is not DBG_VALUE!");
if (MI && MI->getOperand(0).isReg() && MI->getOperand(0).getReg() == OldReg)
MI->getOperand(0).setReg(NewReg);
}
};
}
#endif
|