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
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
//===- NVPTXInstrInfo.cpp - NVPTX Instruction Information -----------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains the NVPTX implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "NVPTXInstrInfo.h"
#include "NVPTX.h"
#include "NVPTXTargetMachine.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/IR/Function.h"
using namespace llvm;
#define GET_INSTRINFO_CTOR_DTOR
#include "NVPTXGenInstrInfo.inc"
// Pin the vtable to this file.
void NVPTXInstrInfo::anchor() {}
NVPTXInstrInfo::NVPTXInstrInfo() : NVPTXGenInstrInfo(), RegInfo() {}
void NVPTXInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
const DebugLoc &DL, MCRegister DestReg,
MCRegister SrcReg, bool KillSrc) const {
const MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
const TargetRegisterClass *DestRC = MRI.getRegClass(DestReg);
const TargetRegisterClass *SrcRC = MRI.getRegClass(SrcReg);
if (RegInfo.getRegSizeInBits(*DestRC) != RegInfo.getRegSizeInBits(*SrcRC))
report_fatal_error("Copy one register into another with a different width");
unsigned Op;
if (DestRC == &NVPTX::Int1RegsRegClass) {
Op = NVPTX::IMOV1rr;
} else if (DestRC == &NVPTX::Int16RegsRegClass) {
Op = NVPTX::IMOV16rr;
} else if (DestRC == &NVPTX::Int32RegsRegClass) {
Op = (SrcRC == &NVPTX::Int32RegsRegClass ? NVPTX::IMOV32rr
: NVPTX::BITCONVERT_32_F2I);
} else if (DestRC == &NVPTX::Int64RegsRegClass) {
Op = (SrcRC == &NVPTX::Int64RegsRegClass ? NVPTX::IMOV64rr
: NVPTX::BITCONVERT_64_F2I);
} else if (DestRC == &NVPTX::Float16RegsRegClass) {
Op = (SrcRC == &NVPTX::Float16RegsRegClass ? NVPTX::FMOV16rr
: NVPTX::BITCONVERT_16_I2F);
} else if (DestRC == &NVPTX::Float16x2RegsRegClass) {
Op = NVPTX::IMOV32rr;
} else if (DestRC == &NVPTX::Float32RegsRegClass) {
Op = (SrcRC == &NVPTX::Float32RegsRegClass ? NVPTX::FMOV32rr
: NVPTX::BITCONVERT_32_I2F);
} else if (DestRC == &NVPTX::Float64RegsRegClass) {
Op = (SrcRC == &NVPTX::Float64RegsRegClass ? NVPTX::FMOV64rr
: NVPTX::BITCONVERT_64_I2F);
} else {
llvm_unreachable("Bad register copy");
}
BuildMI(MBB, I, DL, get(Op), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
}
/// analyzeBranch - Analyze the branching code at the end of MBB, returning
/// true if it cannot be understood (e.g. it's a switch dispatch or isn't
/// implemented for a target). Upon success, this returns false and returns
/// with the following information in various cases:
///
/// 1. If this block ends with no branches (it just falls through to its succ)
/// just return false, leaving TBB/FBB null.
/// 2. If this block ends with only an unconditional branch, it sets TBB to be
/// the destination block.
/// 3. If this block ends with an conditional branch and it falls through to
/// an successor block, it sets TBB to be the branch destination block and a
/// list of operands that evaluate the condition. These
/// operands can be passed to other TargetInstrInfo methods to create new
/// branches.
/// 4. If this block ends with an conditional branch and an unconditional
/// block, it returns the 'true' destination in TBB, the 'false' destination
/// in FBB, and a list of operands that evaluate the condition. These
/// operands can be passed to other TargetInstrInfo methods to create new
/// branches.
///
/// Note that removeBranch and insertBranch must be implemented to support
/// cases where this method returns success.
///
bool NVPTXInstrInfo::analyzeBranch(MachineBasicBlock &MBB,
MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
SmallVectorImpl<MachineOperand> &Cond,
bool AllowModify) const {
// If the block has no terminators, it just falls into the block after it.
MachineBasicBlock::iterator I = MBB.end();
if (I == MBB.begin() || !isUnpredicatedTerminator(*--I))
return false;
// Get the last instruction in the block.
MachineInstr &LastInst = *I;
// If there is only one terminator instruction, process it.
if (I == MBB.begin() || !isUnpredicatedTerminator(*--I)) {
if (LastInst.getOpcode() == NVPTX::GOTO) {
TBB = LastInst.getOperand(0).getMBB();
return false;
} else if (LastInst.getOpcode() == NVPTX::CBranch) {
// Block ends with fall-through condbranch.
TBB = LastInst.getOperand(1).getMBB();
Cond.push_back(LastInst.getOperand(0));
return false;
}
// Otherwise, don't know what this is.
return true;
}
// Get the instruction before it if it's a terminator.
MachineInstr &SecondLastInst = *I;
// If there are three terminators, we don't know what sort of block this is.
if (I != MBB.begin() && isUnpredicatedTerminator(*--I))
return true;
// If the block ends with NVPTX::GOTO and NVPTX:CBranch, handle it.
if (SecondLastInst.getOpcode() == NVPTX::CBranch &&
LastInst.getOpcode() == NVPTX::GOTO) {
TBB = SecondLastInst.getOperand(1).getMBB();
Cond.push_back(SecondLastInst.getOperand(0));
FBB = LastInst.getOperand(0).getMBB();
return false;
}
// If the block ends with two NVPTX:GOTOs, handle it. The second one is not
// executed, so remove it.
if (SecondLastInst.getOpcode() == NVPTX::GOTO &&
LastInst.getOpcode() == NVPTX::GOTO) {
TBB = SecondLastInst.getOperand(0).getMBB();
I = LastInst;
if (AllowModify)
I->eraseFromParent();
return false;
}
// Otherwise, can't handle this.
return true;
}
unsigned NVPTXInstrInfo::removeBranch(MachineBasicBlock &MBB,
int *BytesRemoved) const {
assert(!BytesRemoved && "code size not handled");
MachineBasicBlock::iterator I = MBB.end();
if (I == MBB.begin())
return 0;
--I;
if (I->getOpcode() != NVPTX::GOTO && I->getOpcode() != NVPTX::CBranch)
return 0;
// Remove the branch.
I->eraseFromParent();
I = MBB.end();
if (I == MBB.begin())
return 1;
--I;
if (I->getOpcode() != NVPTX::CBranch)
return 1;
// Remove the branch.
I->eraseFromParent();
return 2;
}
unsigned NVPTXInstrInfo::insertBranch(MachineBasicBlock &MBB,
MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
ArrayRef<MachineOperand> Cond,
const DebugLoc &DL,
int *BytesAdded) const {
assert(!BytesAdded && "code size not handled");
// Shouldn't be a fall through.
assert(TBB && "insertBranch must not be told to insert a fallthrough");
assert((Cond.size() == 1 || Cond.size() == 0) &&
"NVPTX branch conditions have two components!");
// One-way branch.
if (!FBB) {
if (Cond.empty()) // Unconditional branch
BuildMI(&MBB, DL, get(NVPTX::GOTO)).addMBB(TBB);
else // Conditional branch
BuildMI(&MBB, DL, get(NVPTX::CBranch)).addReg(Cond[0].getReg())
.addMBB(TBB);
return 1;
}
// Two-way Conditional Branch.
BuildMI(&MBB, DL, get(NVPTX::CBranch)).addReg(Cond[0].getReg()).addMBB(TBB);
BuildMI(&MBB, DL, get(NVPTX::GOTO)).addMBB(FBB);
return 2;
}
|