llvm.org GIT mirror llvm / 1b27914 lib / CodeGen / AsmPrinter / DwarfDebug.cpp
1b27914

Tree @1b27914 (Download .tar.gz)

DwarfDebug.cpp @1b27914

0310d76
 
 
 
 
 
 
 
 
 
 
 
6cde3e6
0310d76
a2ec9db
0d27ca1
1b27914
 
f4a635b
d04a8d4
 
 
 
0c36e97
d04a8d4
 
0b8c9a8
7cf9764
0b8c9a8
f4ec8bf
0b8c9a8
 
eb3d76d
b7db733
a87dea4
6c2f9e1
b7db733
eac9c07
6e4bdfc
d7d43dc
f8cc317
6e4bdfc
0ad9c91
80668d1
3dee575
1f6efa3
d04a8d4
 
 
 
 
 
9f85dcc
0310d76
 
8677f2f
 
6e61e0b
 
 
eac9c07
6e61e0b
 
 
 
281d65d
8f1a929
 
 
 
 
5483012
 
 
 
 
20f47ab
2ddf01b
20f47ab
09ac3d8
6e61e0b
 
 
 
 
 
 
20f47ab
6e61e0b
 
e28204e
6e61e0b
 
 
 
f5b6dcd
f04e4ef
63ae7c9
 
 
 
 
 
f04e4ef
0b6962f
 
5f017e8
0310d76
 
8199f0b
 
eee5230
8199f0b
 
 
5e8144d
 
 
 
 
3bbb6f7
5e8144d
3cbee30
 
5e8144d
3cbee30
 
 
 
 
 
0f1c7f6
3cbee30
 
0f1c7f6
3cbee30
 
 
 
 
0f1c7f6
3cbee30
 
0f1c7f6
3cbee30
 
 
 
 
 
3166762
0f1c7f6
4dc211a
8199f0b
0f1c7f6
8e8c1ac
3cbee30
d6dffb4
3cbee30
8199f0b
8bd11de
 
3cbee30
 
0310d76
a0d6bcc
 
 
 
 
49cd664
3ad7d41
22a01da
1c2827c
22a01da
76ff19f
c8bd54b
b536101
 
e33575f
 
a0d6bcc
 
1e20b96
e703fcb
 
 
 
 
 
 
 
60777d8
73df4b9
 
05bae3b
 
 
03be5e5
c1610fa
4daaed1
 
f5b6dcd
05bae3b
 
63ae7c9
 
05bae3b
63ae7c9
f04e4ef
179bb4e
dc352c1
 
0e6783f
bb804ee
 
03c3dc7
 
c4639d6
9c42107
0310d76
 
79844fc
 
 
b6dc865
 
7ee5f5d
e703fcb
d8a8752
eee5230
e703fcb
d8a8752
 
 
 
 
 
0ffe2b4
 
 
 
 
eee5230
 
0ffe2b4
4321d4e
0ffe2b4
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7c9659a
 
eee5230
 
 
7c9659a
 
0ffe2b4
9e0b08d
 
 
d48f5ef
eee5230
 
c8bd54b
0ffe2b4
 
 
 
c8bd54b
0ffe2b4
 
 
 
 
 
b536101
0ffe2b4
b536101
0ffe2b4
c8bd54b
0ffe2b4
 
 
02d2967
 
 
 
 
 
 
 
 
2c9905a
02d2967
 
 
995de6c
 
fd2210a
 
 
 
995de6c
fd2210a
 
 
 
 
 
 
995de6c
 
b8ee7c2
fd2210a
 
f49ead7
 
 
 
 
 
127cb8e
becd8e7
4b26377
 
becd8e7
43ed8ae
4b26377
df89f0d
 
111bad3
 
f49ead7
 
 
 
4b26377
becd8e7
f6e0037
a18dcd4
 
 
875f90e
a18dcd4
 
4a644cc
72c1655
875f90e
65dbc90
6c1a703
0310d76
875f90e
9feea1a
875f90e
c5211fe
875f90e
67177d3
 
875f90e
b5a1fcc
 
 
 
56ce2f5
2a12c4e
875f90e
5877a5b
c5211fe
 
1a4a8b9
c5211fe
e0828ec
 
875f90e
0310d76
0b15e98
 
 
c5211fe
8f1a929
c5211fe
0b15e98
8f1a929
94d04b8
c5211fe
0310d76
65dbc90
 
c5211fe
0f1c7f6
d5d5213
c5211fe
1a4a8b9
0310d76
67177d3
875f90e
1a4a8b9
67177d3
875f90e
1a4a8b9
bba2331
875f90e
c5211fe
94c7ddb
f0fb987
0310d76
677ae42
 
20d9e41
cec7ce7
875f90e
d53f7f4
c462db6
 
b6dc865
 
 
c4639d6
eac9c07
 
 
c4639d6
 
e27d5a0
 
30692ab
c0ec8a4
02e603f
bc66071
d850ac7
c0ec8a4
 
 
56ce2f5
2a12c4e
5bf8ade
 
875f90e
20d9e41
 
d2e0f7e
20d9e41
 
d2e0f7e
0b6962f
c0ec8a4
 
f5938ee
3f4b69d
 
 
c0ec8a4
2bd885a
 
 
 
 
 
 
c0ec8a4
ff5abbb
 
 
 
 
875f90e
ff5abbb
c462db6
 
20d9e41
677ae42
c0ec8a4
0f1c7f6
d850ac7
 
0f1c7f6
94d04b8
5cc319a
94d04b8
0310d76
0fcb9cb
 
 
524cd2e
0fcb9cb
 
 
 
 
f154f3b
0fcb9cb
 
 
 
 
 
 
 
def5a05
6808453
f49ead7
 
 
def5a05
 
 
4117bec
 
4a1cad6
1e20b96
94c7ddb
5bf8ade
 
3f62ac3
 
 
 
94c7ddb
 
bdab800
c622824
 
54a86b3
4a1cad6
 
 
4117bec
 
 
254d093
 
0fcb9cb
 
4117bec
 
0310d76
3f8689f
 
a49cbec
 
f962c02
 
a49cbec
f962c02
ff37ddf
a49cbec
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
fcd4288
a49cbec
 
 
 
5be7776
a49cbec
 
 
 
 
 
b1494f1
42090c6
 
a49cbec
 
 
 
 
42090c6
 
 
f962c02
 
 
 
0e3e9b7
 
 
4117bec
 
 
eee5230
3bfc4d8
5cc319a
 
 
 
 
 
 
 
 
e703fcb
5cc319a
 
 
7c9659a
 
3bfc4d8
 
7c9659a
 
 
 
 
 
 
 
3bfc4d8
7c9659a
e703fcb
0310d76
5cc319a
7c9659a
eee5230
8e290f5
 
7c9659a
5cc319a
 
 
 
 
e703fcb
94d04b8
4117bec
0310d76
b6dc865
4117bec
c34a25d
 
4117bec
3ad7d41
 
 
 
eee5230
4117bec
 
 
 
 
 
 
0310d76
d2b3a02
9e0b08d
d2b3a02
 
74802f7
d2b3a02
 
4288502
d2b3a02
5483012
 
4288502
d2b3a02
 
4288502
d2b3a02
 
98e237f
6eebe47
9c1e56a
6072096
72f7bfb
08e5ef2
5b8e479
 
 
0310d76
9d9f5a5
20f47ab
09ac3d8
 
 
 
 
0f1c7f6
2612354
 
e56a4d9
 
2612354
193f720
e9a1cca
94c7ddb
3043645
94d04b8
0310d76
b6dc865
9907af9
06ac3ff
b549bcf
 
06ac3ff
 
 
 
 
 
3043645
 
06ac3ff
 
90a48ad
f154f3b
 
 
 
 
d32eccc
 
02474a3
8a5eafb
d32eccc
90a48ad
 
d32eccc
 
06ac3ff
d32eccc
 
06ac3ff
d32eccc
06ac3ff
 
d32eccc
 
 
06ac3ff
d32eccc
 
06ac3ff
 
d32eccc
06ac3ff
 
b6dc865
eee5230
431bdfc
3bfc4d8
1ceef0e
eee5230
1ceef0e
 
1e20b96
fb0ee43
e703fcb
fb0ee43
53bb5c9
f921907
 
d32eccc
02474a3
0fcb9cb
ada34b3
8a5eafb
e717faa
ee43286
 
b6dc865
eccd574
02474a3
b7b9bf4
90b4041
02474a3
3517640
90b4041
3517640
 
 
13131e6
 
 
02474a3
90b4041
 
02474a3
90b4041
02474a3
90b4041
02474a3
90b4041
02474a3
90b4041
 
2a39c99
02474a3
2a39c99
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5bfa4ba
 
 
59b6049
2a39c99
 
 
 
 
 
 
ee8b879
 
2a39c99
 
 
 
 
02474a3
59b6049
79fb67b
02474a3
 
2a39c99
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5bfa4ba
0ca6b9f
 
 
02474a3
0ca6b9f
59b6049
0ca6b9f
 
 
 
 
 
 
 
 
 
db72188
 
 
2a39c99
 
0ca6b9f
 
 
 
 
 
 
2a39c99
02474a3
 
 
 
 
 
 
 
2a39c99
 
 
 
b6dc865
1e20b96
ee129ed
 
4e97645
ac07cd5
90a48ad
5c91f4d
 
 
ee43286
90a48ad
a807d67
 
 
adb877d
c3f5f78
e703fcb
263998a
ee8af3e
 
 
 
 
ee43286
c0c5a26
ee43286
 
02474a3
a807d67
adb877d
d32eccc
 
0fcb9cb
8a5eafb
adb877d
a807d67
e457dc7
c3f5f78
 
498703b
ada34b3
28cf115
b2d73d1
 
ee129ed
b2d73d1
 
2a39c99
 
5bfa4ba
90a48ad
98e1cac
 
ee129ed
93d39be
 
3f62ac3
5401ba7
93d39be
ad03fa6
d32eccc
02474a3
 
8a5eafb
ad03fa6
98e1cac
c3f5f78
 
b6dc865
72f7bfb
adb877d
 
 
c3f5f78
98e1cac
b6dc865
72f7bfb
adb877d
e717faa
 
b6dc865
cbbe287
c34a25d
ac07cd5
15a3ea0
 
 
 
60b35f4
15a3ea0
4243e67
 
 
1d68fc5
4243e67
1d68fc5
 
60b35f4
 
15a3ea0
 
4243e67
15a3ea0
e703fcb
15a3ea0
b2b31a6
 
15a3ea0
eee5230
 
adb877d
 
 
 
 
 
 
553881b
b2b31a6
15a3ea0
77051f5
 
eac9c07
adb877d
0d20ac8
 
b6dc865
ac07cd5
c34a25d
15a3ea0
 
ac07cd5
e703fcb
15a3ea0
eee5230
ac07cd5
e703fcb
adb877d
 
 
 
 
 
 
15a3ea0
 
 
 
 
 
1c24635
adb877d
53bb5c9
 
b6dc865
 
 
 
e37b0c6
bf47fdb
 
42aafd7
bf47fdb
1e20b96
9f43ac6
1e20b96
3bfc4d8
42aafd7
53bb5c9
 
1e20b96
3bfc4d8
 
 
 
 
eac9c07
af9e847
 
 
f9e42bc
 
 
 
 
 
6f059af
 
 
 
f9e42bc
6f059af
f9e42bc
 
 
b6dc865
 
eec791a
ac07cd5
31ed50c
 
 
 
 
e27d5a0
 
 
 
31ed50c
 
bf47fdb
8b97f00
31ed50c
 
5c91f4d
31ed50c
 
bf47fdb
60b35bd
4a644cc
31ed50c
 
43213cf
e27d5a0
 
 
 
 
 
 
 
4a644cc
43213cf
f392976
 
01cb18e
 
 
43213cf
31ed50c
 
94d04b8
eac9c07
94d04b8
d51ae64
9f85dcc
 
d51ae64
 
a807d67
 
 
adb877d
 
d51ae64
 
02474a3
 
 
 
 
2a39c99
 
02474a3
2a39c99
02474a3
 
2a39c99
 
 
 
 
 
 
d51ae64
a807d67
 
 
 
adb877d
 
b2b31a6
15a3ea0
b2b31a6
4243e67
 
f9e42bc
4243e67
31ed50c
ab42578
31ed50c
 
 
 
 
 
4243e67
0310d76
 
b6dc865
b5dd669
2b0657e
 
ac07cd5
e27d5a0
 
8b97f00
 
 
 
e703fcb
eee5230
ac07cd5
65eb482
bf47fdb
eee5230
bf47fdb
 
65a1296
4a644cc
43213cf
0f1c7f6
d0b5a5e
ee129ed
 
 
 
 
d0b5a5e
9e4e3d0
 
 
 
 
 
76ff19f
7f6ba17
9e4e3d0
5465cc6
 
9e4e3d0
 
 
 
 
 
 
 
2273ca1
 
 
bf47fdb
3bfc4d8
cd9f6c5
d2e8729
9f84cec
 
 
 
 
5401ba7
9f84cec
d32eccc
2273ca1
 
78e127d
127cb8e
bf47fdb
0f1c7f6
7cb5e0f
f49ead7
 
 
d0b5a5e
94d04b8
3043645
 
 
7f6ba17
adb877d
eac9c07
 
e703fcb
 
f0fb987
0310d76
b6dc865
 
4243e67
 
65dbc90
23670e5
1cc0d62
6f8c0c0
44623e8
 
 
 
c726020
 
1cc0d62
1881227
0eb05e2
 
1cc0d62
6f8c0c0
 
0310d76
 
829e67b
 
 
 
b6dc865
7ee5f5d
6c2f9e1
f612ff6
94d04b8
1e20b96
eee5230
fcfd562
5be7776
 
fcfd562
 
 
1e20b96
eee5230
6eebe47
eee5230
 
889b129
 
1e20b96
7a0103c
eee5230
cdeaae4
a6d8415
 
 
 
cdeaae4
 
 
dc42d03
8f1a929
1e20b96
eee5230
9a9e73b
64f824c
eee5230
9a9e73b
eee5230
fabe5ce
b13d54f
 
 
 
eee5230
 
63ad10c
0310d76
b6dc865
4035266
94d04b8
4035266
63ad10c
94d04b8
3f53c83
7afb463
4035266
 
7afb463
 
63ad10c
4035266
7afb463
0310d76
94d04b8
 
770530b
 
94d04b8
0310d76
26148a6
a801362
26148a6
 
 
 
1e20b96
001e676
 
94d04b8
0310d76
94d04b8
8b3fad9
4035266
 
0310d76
ec112cf
233f52b
f0fb987
94d04b8
0310d76
98e237f
 
60e5b16
b1e66d0
22a01da
98e237f
 
b6dc865
7dc68db
60e5b16
0d66821
 
6eebe47
 
b6dc865
2c4ceb1
94d04b8
233f52b
 
1e20b96
233f52b
426c2bf
233f52b
 
 
 
d85fc6e
eee5230
 
 
0310d76
94d04b8
233f52b
 
0ad9c91
894d75a
94d04b8
0310d76
85d436d
 
 
 
 
09ac3d8
 
 
72c32c6
85d436d
 
 
 
 
 
09ac3d8
 
72c1655
 
09ac3d8
85d436d
 
09ac3d8
 
b6dc865
09ac3d8
85d436d
 
 
09ac3d8
 
b6dc865
09ac3d8
85d436d
 
09ac3d8
 
8f1a929
 
 
 
 
 
 
 
 
 
 
 
 
 
 
59e818d
ba5ab82
a486f55
 
 
 
 
 
172515f
 
a486f55
 
 
8f1a929
 
 
 
 
 
cdeaae4
 
 
 
8f1a929
 
 
9599f51
8f1a929
9599f51
8f1a929
a31a975
8f1a929
 
a31a975
8f1a929
9599f51
 
8f1a929
9599f51
8f1a929
 
 
5747932
c5ef7ee
8f1a929
 
 
 
c5ef7ee
21cd65a
 
e98b0e4
 
 
 
21cd65a
4b2ab80
 
ef953d6
 
 
1c7fef1
 
 
bf29eb3
4b2ab80
451fa97
c5ef7ee
 
21a6a50
c5ef7ee
8f1a929
e98b0e4
 
 
3ddd790
c5ef7ee
3ddd790
c5ef7ee
 
d7d43dc
c5ef7ee
 
b0ec1be
c5ef7ee
 
8ff4876
c5ef7ee
8f1a929
ef953d6
3bfc4d8
 
c5ef7ee
 
 
 
8f1a929
451fa97
18a6ade
ac3f016
994c37f
18a6ade
8f1a929
 
ec112cf
3bfc4d8
c5ef7ee
 
 
 
3ddd790
c5ef7ee
 
 
8f1a929
cdeaae4
 
 
5704d64
21cd65a
 
193f720
 
64f824c
 
60e5b16
64f824c
 
 
2a39c99
 
 
 
b89cf2a
79fb67b
2a39c99
b89cf2a
 
2a39c99
 
b89cf2a
9fb34c5
02474a3
 
 
b89cf2a
2a39c99
 
9fb34c5
2a39c99
 
 
 
10c4265
02474a3
 
2a39c99
 
 
 
 
 
57ed5ff
 
2a39c99
 
 
 
096eaf8
b005e96
eccd574
79fb67b
2a39c99
 
 
 
 
 
 
 
57ed5ff
 
79fb67b
57ed5ff
 
2a39c99
eccd574
5e8144d
096eaf8
7521234
57ed5ff
7521234
57ed5ff
eccd574
 
02474a3
57ed5ff
096eaf8
 
 
 
57ed5ff
 
 
 
 
 
 
 
096eaf8
 
 
 
 
 
 
6b10f3a
 
 
 
 
 
 
 
 
 
 
 
 
d3b9853
2c4ceb1
83320a0
6c2f9e1
5b8e479
426c2bf
0f53443
b2d73d1
5bfa4ba
b2d73d1
8b97f00
 
 
dc1d16a
8b97f00
 
 
 
 
 
5b8e479
6b10f3a
c3f5f78
5b8e479
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
08e5ef2
5b8e479
 
 
 
b13d54f
5b8e479
c3f5f78
94d04b8
0310d76
5cc319a
 
 
 
 
 
7ee5f5d
94d04b8
eee5230
 
5cc319a
dc352c1
5cc319a
 
 
 
 
3bfc4d8
 
5cc319a
 
 
 
 
 
 
 
3bfc4d8
ada34b3
5cc319a
 
 
 
adb294d
 
 
 
 
 
 
 
 
 
 
 
 
5cc319a
 
 
e703fcb
3bfc4d8
5cc319a
 
e703fcb
5cc319a
 
 
 
 
 
3bfc4d8
5cc319a
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4a644cc
3bfc4d8
 
5cc319a
 
 
 
adb294d
 
 
5cc319a
 
3bfc4d8
5cc319a
 
d998d1c
 
 
 
5cc319a
eee5230
 
 
 
 
5cc319a
 
 
 
5f9cb7b
 
5cc319a
 
 
 
 
 
 
 
 
 
d998d1c
5cc319a
 
 
 
 
5f9cb7b
5cc319a
3bfc4d8
5cc319a
 
 
eb46def
5cc319a
eb46def
 
 
 
 
 
 
 
 
5cc319a
 
 
 
 
 
63ad10c
 
b6dc865
2c4ceb1
94d04b8
eee5230
 
c2efbdb
 
426c2bf
c2efbdb
 
3bfc4d8
 
c2efbdb
f49ead7
 
 
c2efbdb
3bfc4d8
856d2fc
 
c2efbdb
3bfc4d8
c2efbdb
 
d1946f7
 
dc1d16a
eed2620
 
 
 
 
 
c2efbdb
 
 
 
ca1dd05
c2efbdb
f2548ca
94d04b8
 
0b944ee
98e237f
f6e0037
875f90e
67177d3
e8e0fcf
6fc76f3
 
67177d3
6fc76f3
875f90e
6fc76f3
875f90e
6fc76f3
 
98e237f
 
882d89e
875f90e
98e237f
875f90e
9feea1a
875f90e
 
1a4a8b9
446b88f
875f90e
98e237f
c5211fe
0e3e9b7
98e237f
 
 
0b944ee
 
98e237f
4daaed1
d486d10
 
22a01da
6eebe47
 
 
 
 
 
0d66821
98e237f
64f824c
9c1e56a
 
 
 
c5b39af
9c1e56a
 
64f824c
 
 
 
 
eee5230
 
dd8e9f3
85d436d
64f824c
6fe6dc1
56ce2f5
 
 
 
 
 
 
 
f95477d
 
 
 
 
 
 
 
 
 
 
c6c93e9
f6e0037
2af945d
4f18a81
 
 
 
 
 
2cb3295
d157171
c6c93e9
d157171
 
 
4f18a81
 
 
fcfd562
 
 
875f90e
c5211fe
875f90e
dc352c1
 
875f90e
c5211fe
1a4a8b9
d157171
f95477d
875f90e
f95477d
fcfd562
33e0758
fcfd562
c5211fe
fcfd562
 
 
d157171
f95477d
 
4f18a81
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
ad2a271
4f18a81
 
875f90e
6fe6dc1
5ba79a9
c8bd54b
 
 
 
d48f5ef
c8bd54b
 
82a35bf
 
c8bd54b
b536101
d48f5ef
b536101
 
82a35bf
 
b536101
e33575f
d48f5ef
e33575f
 
82a35bf
 
e33575f
a0d6bcc
d48f5ef
a0d6bcc
 
82a35bf
 
a0d6bcc
   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
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
//===-- llvm/CodeGen/DwarfDebug.cpp - Dwarf Debug Framework ---------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains support for writing dwarf debug info into asm files.
//
//===----------------------------------------------------------------------===//

#include "DwarfDebug.h"
#include "ByteStreamer.h"
#include "DIEHash.h"
#include "DwarfCompileUnit.h"
#include "DwarfExpression.h"
#include "DwarfUnit.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/CodeGen/DIE.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DIBuilder.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/LEB128.h"
#include "llvm/Support/MD5.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/Timer.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetSubtargetInfo.h"
using namespace llvm;

#define DEBUG_TYPE "dwarfdebug"

static cl::opt<bool>
DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden,
                         cl::desc("Disable debug info printing"));

static cl::opt<bool> UnknownLocations(
    "use-unknown-locations", cl::Hidden,
    cl::desc("Make an absence of debug location information explicit."),
    cl::init(false));

static cl::opt<bool>
GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden,
                       cl::desc("Generate GNU-style pubnames and pubtypes"),
                       cl::init(false));

static cl::opt<bool> GenerateARangeSection("generate-arange-section",
                                           cl::Hidden,
                                           cl::desc("Generate dwarf aranges"),
                                           cl::init(false));

namespace {
enum DefaultOnOff { Default, Enable, Disable };
}

static cl::opt<DefaultOnOff>
DwarfAccelTables("dwarf-accel-tables", cl::Hidden,
                 cl::desc("Output prototype dwarf accelerator tables."),
                 cl::values(clEnumVal(Default, "Default for platform"),
                            clEnumVal(Enable, "Enabled"),
                            clEnumVal(Disable, "Disabled"), clEnumValEnd),
                 cl::init(Default));

static cl::opt<DefaultOnOff>
SplitDwarf("split-dwarf", cl::Hidden,
           cl::desc("Output DWARF5 split debug info."),
           cl::values(clEnumVal(Default, "Default for platform"),
                      clEnumVal(Enable, "Enabled"),
                      clEnumVal(Disable, "Disabled"), clEnumValEnd),
           cl::init(Default));

static cl::opt<DefaultOnOff>
DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden,
                 cl::desc("Generate DWARF pubnames and pubtypes sections"),
                 cl::values(clEnumVal(Default, "Default for platform"),
                            clEnumVal(Enable, "Enabled"),
                            clEnumVal(Disable, "Disabled"), clEnumValEnd),
                 cl::init(Default));

static const char *const DWARFGroupName = "DWARF Emission";
static const char *const DbgTimerName = "DWARF Debug Writer";

//===----------------------------------------------------------------------===//

/// resolve - Look in the DwarfDebug map for the MDNode that
/// corresponds to the reference.
template <typename T> T DbgVariable::resolve(DIRef<T> Ref) const {
  return DD->resolve(Ref);
}

bool DbgVariable::isBlockByrefVariable() const {
  assert(Var.isVariable() && "Invalid complex DbgVariable!");
  return Var.isBlockByrefVariable(DD->getTypeIdentifierMap());
}

DIType DbgVariable::getType() const {
  DIType Ty = Var.getType().resolve(DD->getTypeIdentifierMap());
  // FIXME: isBlockByrefVariable should be reformulated in terms of complex
  // addresses instead.
  if (Var.isBlockByrefVariable(DD->getTypeIdentifierMap())) {
    /* Byref variables, in Blocks, are declared by the programmer as
       "SomeType VarName;", but the compiler creates a
       __Block_byref_x_VarName struct, and gives the variable VarName
       either the struct, or a pointer to the struct, as its type.  This
       is necessary for various behind-the-scenes things the compiler
       needs to do with by-reference variables in blocks.

       However, as far as the original *programmer* is concerned, the
       variable should still have type 'SomeType', as originally declared.

       The following function dives into the __Block_byref_x_VarName
       struct to find the original type of the variable.  This will be
       passed back to the code generating the type for the Debug
       Information Entry for the variable 'VarName'.  'VarName' will then
       have the original type 'SomeType' in its debug information.

       The original type 'SomeType' will be the type of the field named
       'VarName' inside the __Block_byref_x_VarName struct.

       NOTE: In order for this to not completely fail on the debugger
       side, the Debug Information Entry for the variable VarName needs to
       have a DW_AT_location that tells the debugger how to unwind through
       the pointers and __Block_byref_x_VarName struct to find the actual
       value of the variable.  The function addBlockByrefType does this.  */
    DIType subType = Ty;
    uint16_t tag = Ty.getTag();

    if (tag == dwarf::DW_TAG_pointer_type)
      subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom());

    DIArray Elements = DICompositeType(subType).getElements();
    for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
      DIDerivedType DT(Elements.getElement(i));
      if (getName() == DT.getName())
        return (resolve(DT.getTypeDerivedFrom()));
    }
  }
  return Ty;
}

static LLVM_CONSTEXPR DwarfAccelTable::Atom TypeAtoms[] = {
    DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4),
    DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2),
    DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1)};

DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
    : Asm(A), MMI(Asm->MMI), PrevLabel(nullptr), GlobalRangeCount(0),
      InfoHolder(A, *this, "info_string", DIEValueAllocator),
      UsedNonDefaultText(false),
      SkeletonHolder(A, *this, "skel_string", DIEValueAllocator),
      IsDarwin(Triple(A->getTargetTriple()).isOSDarwin()),
      AccelNames(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
                                       dwarf::DW_FORM_data4)),
      AccelObjC(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
                                      dwarf::DW_FORM_data4)),
      AccelNamespace(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
                                           dwarf::DW_FORM_data4)),
      AccelTypes(TypeAtoms) {

  DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = nullptr;
  DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = nullptr;
  DwarfLineSectionSym = nullptr;
  DwarfAddrSectionSym = nullptr;
  DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = nullptr;
  FunctionBeginSym = FunctionEndSym = nullptr;
  CurFn = nullptr;
  CurMI = nullptr;

  // Turn on accelerator tables for Darwin by default, pubnames by
  // default for non-Darwin, and handle split dwarf.
  if (DwarfAccelTables == Default)
    HasDwarfAccelTables = IsDarwin;
  else
    HasDwarfAccelTables = DwarfAccelTables == Enable;

  if (SplitDwarf == Default)
    HasSplitDwarf = false;
  else
    HasSplitDwarf = SplitDwarf == Enable;

  if (DwarfPubSections == Default)
    HasDwarfPubSections = !IsDarwin;
  else
    HasDwarfPubSections = DwarfPubSections == Enable;

  unsigned DwarfVersionNumber = Asm->TM.Options.MCOptions.DwarfVersion;
  DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber
                                    : MMI->getModule()->getDwarfVersion();

  Asm->OutStreamer.getContext().setDwarfVersion(DwarfVersion);

  {
    NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
    beginModule();
  }
}

// Define out of line so we don't have to include DwarfUnit.h in DwarfDebug.h.
DwarfDebug::~DwarfDebug() { }

// Switch to the specified MCSection and emit an assembler
// temporary label to it if SymbolStem is specified.
static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section,
                                const char *SymbolStem = nullptr) {
  Asm->OutStreamer.SwitchSection(Section);
  if (!SymbolStem)
    return nullptr;

  MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem);
  Asm->OutStreamer.EmitLabel(TmpSym);
  return TmpSym;
}

static bool isObjCClass(StringRef Name) {
  return Name.startswith("+") || Name.startswith("-");
}

static bool hasObjCCategory(StringRef Name) {
  if (!isObjCClass(Name))
    return false;

  return Name.find(") ") != StringRef::npos;
}

static void getObjCClassCategory(StringRef In, StringRef &Class,
                                 StringRef &Category) {
  if (!hasObjCCategory(In)) {
    Class = In.slice(In.find('[') + 1, In.find(' '));
    Category = "";
    return;
  }

  Class = In.slice(In.find('[') + 1, In.find('('));
  Category = In.slice(In.find('[') + 1, In.find(' '));
  return;
}

static StringRef getObjCMethodName(StringRef In) {
  return In.slice(In.find(' ') + 1, In.find(']'));
}

// Helper for sorting sections into a stable output order.
static bool SectionSort(const MCSection *A, const MCSection *B) {
  std::string LA = (A ? A->getLabelBeginName() : "");
  std::string LB = (B ? B->getLabelBeginName() : "");
  return LA < LB;
}

// Add the various names to the Dwarf accelerator table names.
// TODO: Determine whether or not we should add names for programs
// that do not have a DW_AT_name or DW_AT_linkage_name field - this
// is only slightly different than the lookup of non-standard ObjC names.
void DwarfDebug::addSubprogramNames(DISubprogram SP, DIE &Die) {
  if (!SP.isDefinition())
    return;
  addAccelName(SP.getName(), Die);

  // If the linkage name is different than the name, go ahead and output
  // that as well into the name table.
  if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName())
    addAccelName(SP.getLinkageName(), Die);

  // If this is an Objective-C selector name add it to the ObjC accelerator
  // too.
  if (isObjCClass(SP.getName())) {
    StringRef Class, Category;
    getObjCClassCategory(SP.getName(), Class, Category);
    addAccelObjC(Class, Die);
    if (Category != "")
      addAccelObjC(Category, Die);
    // Also add the base method name to the name table.
    addAccelName(getObjCMethodName(SP.getName()), Die);
  }
}

/// isSubprogramContext - Return true if Context is either a subprogram
/// or another context nested inside a subprogram.
bool DwarfDebug::isSubprogramContext(const MDNode *Context) {
  if (!Context)
    return false;
  DIDescriptor D(Context);
  if (D.isSubprogram())
    return true;
  if (D.isType())
    return isSubprogramContext(resolve(DIType(Context).getContext()));
  return false;
}

/// Check whether we should create a DIE for the given Scope, return true
/// if we don't create a DIE (the corresponding DIE is null).
bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) {
  if (Scope->isAbstractScope())
    return false;

  // We don't create a DIE if there is no Range.
  const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges();
  if (Ranges.empty())
    return true;

  if (Ranges.size() > 1)
    return false;

  // We don't create a DIE if we have a single Range and the end label
  // is null.
  return !getLabelAfterInsn(Ranges.front().second);
}

template <typename Func> void forBothCUs(DwarfCompileUnit &CU, Func F) {
  F(CU);
  if (auto *SkelCU = CU.getSkeleton())
    F(*SkelCU);
}

void DwarfDebug::constructAbstractSubprogramScopeDIE(LexicalScope *Scope) {
  assert(Scope && Scope->getScopeNode());
  assert(Scope->isAbstractScope());
  assert(!Scope->getInlinedAt());

  const MDNode *SP = Scope->getScopeNode();

  ProcessedSPNodes.insert(SP);

  // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
  // was inlined from another compile unit.
  auto &CU = SPMap[SP];
  forBothCUs(*CU, [&](DwarfCompileUnit &CU) {
    CU.constructAbstractSubprogramScopeDIE(Scope);
  });
}

void DwarfDebug::addGnuPubAttributes(DwarfUnit &U, DIE &D) const {
  if (!GenerateGnuPubSections)
    return;

  U.addFlag(D, dwarf::DW_AT_GNU_pubnames);
}

// Create new DwarfCompileUnit for the given metadata node with tag
// DW_TAG_compile_unit.
DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
  StringRef FN = DIUnit.getFilename();
  CompilationDir = DIUnit.getDirectory();

  auto OwnedUnit = make_unique<DwarfCompileUnit>(
      InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder);
  DwarfCompileUnit &NewCU = *OwnedUnit;
  DIE &Die = NewCU.getUnitDie();
  InfoHolder.addUnit(std::move(OwnedUnit));
  if (useSplitDwarf())
    NewCU.setSkeleton(constructSkeletonCU(NewCU));

  // LTO with assembly output shares a single line table amongst multiple CUs.
  // To avoid the compilation directory being ambiguous, let the line table
  // explicitly describe the directory of all files, never relying on the
  // compilation directory.
  if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU)
    Asm->OutStreamer.getContext().setMCLineTableCompilationDir(
        NewCU.getUniqueID(), CompilationDir);

  NewCU.addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
  NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
                DIUnit.getLanguage());
  NewCU.addString(Die, dwarf::DW_AT_name, FN);

  if (!useSplitDwarf()) {
    NewCU.initStmtList(DwarfLineSectionSym);

    // If we're using split dwarf the compilation dir is going to be in the
    // skeleton CU and so we don't need to duplicate it here.
    if (!CompilationDir.empty())
      NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);

    addGnuPubAttributes(NewCU, Die);
  }

  if (DIUnit.isOptimized())
    NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized);

  StringRef Flags = DIUnit.getFlags();
  if (!Flags.empty())
    NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags);

  if (unsigned RVer = DIUnit.getRunTimeVersion())
    NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
                  dwarf::DW_FORM_data1, RVer);

  if (useSplitDwarf())
    NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
                      DwarfInfoDWOSectionSym);
  else
    NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
                      DwarfInfoSectionSym);

  CUMap.insert(std::make_pair(DIUnit, &NewCU));
  CUDieMap.insert(std::make_pair(&Die, &NewCU));
  return NewCU;
}

void DwarfDebug::constructAndAddImportedEntityDIE(DwarfCompileUnit &TheCU,
                                                  const MDNode *N) {
  DIImportedEntity Module(N);
  assert(Module.Verify());
  if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext()))
    D->addChild(TheCU.constructImportedEntityDIE(Module));
}

// Emit all Dwarf sections that should come prior to the content. Create
// global DIEs and emit initial debug info sections. This is invoked by
// the target AsmPrinter.
void DwarfDebug::beginModule() {
  if (DisableDebugInfoPrinting)
    return;

  const Module *M = MMI->getModule();

  FunctionDIs = makeSubprogramMap(*M);

  NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
  if (!CU_Nodes)
    return;
  TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);

  // Emit initial sections so we can reference labels later.
  emitSectionLabels();

  SingleCU = CU_Nodes->getNumOperands() == 1;

  for (MDNode *N : CU_Nodes->operands()) {
    DICompileUnit CUNode(N);
    DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
    DIArray ImportedEntities = CUNode.getImportedEntities();
    for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
      ScopesWithImportedEntities.push_back(std::make_pair(
          DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
          ImportedEntities.getElement(i)));
    std::sort(ScopesWithImportedEntities.begin(),
              ScopesWithImportedEntities.end(), less_first());
    DIArray GVs = CUNode.getGlobalVariables();
    for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
      CU.getOrCreateGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
    DIArray SPs = CUNode.getSubprograms();
    for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
      SPMap.insert(std::make_pair(SPs.getElement(i), &CU));
    DIArray EnumTypes = CUNode.getEnumTypes();
    for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i) {
      DIType Ty(EnumTypes.getElement(i));
      // The enum types array by design contains pointers to
      // MDNodes rather than DIRefs. Unique them here.
      DIType UniqueTy(resolve(Ty.getRef()));
      CU.getOrCreateTypeDIE(UniqueTy);
    }
    DIArray RetainedTypes = CUNode.getRetainedTypes();
    for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
      DIType Ty(RetainedTypes.getElement(i));
      // The retained types array by design contains pointers to
      // MDNodes rather than DIRefs. Unique them here.
      DIType UniqueTy(resolve(Ty.getRef()));
      CU.getOrCreateTypeDIE(UniqueTy);
    }
    // Emit imported_modules last so that the relevant context is already
    // available.
    for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
      constructAndAddImportedEntityDIE(CU, ImportedEntities.getElement(i));
  }

  // Tell MMI that we have debug info.
  MMI->setDebugInfoAvailability(true);

  // Prime section data.
  SectionMap[Asm->getObjFileLowering().getTextSection()];
}

void DwarfDebug::finishVariableDefinitions() {
  for (const auto &Var : ConcreteVariables) {
    DIE *VariableDie = Var->getDIE();
    assert(VariableDie);
    // FIXME: Consider the time-space tradeoff of just storing the unit pointer
    // in the ConcreteVariables list, rather than looking it up again here.
    // DIE::getUnit isn't simple - it walks parent pointers, etc.
    DwarfCompileUnit *Unit = lookupUnit(VariableDie->getUnit());
    assert(Unit);
    DbgVariable *AbsVar = getExistingAbstractVariable(Var->getVariable());
    if (AbsVar && AbsVar->getDIE()) {
      Unit->addDIEEntry(*VariableDie, dwarf::DW_AT_abstract_origin,
                        *AbsVar->getDIE());
    } else
      Unit->applyVariableAttributes(*Var, *VariableDie);
  }
}

void DwarfDebug::finishSubprogramDefinitions() {
  for (const auto &P : SPMap)
    forBothCUs(*P.second, [&](DwarfCompileUnit &CU) {
      CU.finishSubprogramDefinition(DISubprogram(P.first));
    });
}


// Collect info for variables that were optimized out.
void DwarfDebug::collectDeadVariables() {
  const Module *M = MMI->getModule();

  if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
    for (MDNode *N : CU_Nodes->operands()) {
      DICompileUnit TheCU(N);
      // Construct subprogram DIE and add variables DIEs.
      DwarfCompileUnit *SPCU =
          static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
      assert(SPCU && "Unable to find Compile Unit!");
      DIArray Subprograms = TheCU.getSubprograms();
      for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
        DISubprogram SP(Subprograms.getElement(i));
        if (ProcessedSPNodes.count(SP) != 0)
          continue;
        SPCU->collectDeadVariables(SP);
      }
    }
  }
}

void DwarfDebug::finalizeModuleInfo() {
  finishSubprogramDefinitions();

  finishVariableDefinitions();

  // Collect info for variables that were optimized out.
  collectDeadVariables();

  // Handle anything that needs to be done on a per-unit basis after
  // all other generation.
  for (const auto &P : CUMap) {
    auto &TheCU = *P.second;
    // Emit DW_AT_containing_type attribute to connect types with their
    // vtable holding type.
    TheCU.constructContainingTypeDIEs();

    // Add CU specific attributes if we need to add any.
    // If we're splitting the dwarf out now that we've got the entire
    // CU then add the dwo id to it.
    auto *SkCU = TheCU.getSkeleton();
    if (useSplitDwarf()) {
      // Emit a unique identifier for this CU.
      uint64_t ID = DIEHash(Asm).computeCUSignature(TheCU.getUnitDie());
      TheCU.addUInt(TheCU.getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
                    dwarf::DW_FORM_data8, ID);
      SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
                    dwarf::DW_FORM_data8, ID);

      // We don't keep track of which addresses are used in which CU so this
      // is a bit pessimistic under LTO.
      if (!AddrPool.isEmpty())
        SkCU->addSectionLabel(SkCU->getUnitDie(), dwarf::DW_AT_GNU_addr_base,
                              DwarfAddrSectionSym, DwarfAddrSectionSym);
      if (!SkCU->getRangeLists().empty())
        SkCU->addSectionLabel(SkCU->getUnitDie(), dwarf::DW_AT_GNU_ranges_base,
                              DwarfDebugRangeSectionSym,
                              DwarfDebugRangeSectionSym);
    }

    // If we have code split among multiple sections or non-contiguous
    // ranges of code then emit a DW_AT_ranges attribute on the unit that will
    // remain in the .o file, otherwise add a DW_AT_low_pc.
    // FIXME: We should use ranges allow reordering of code ala
    // .subsections_via_symbols in mach-o. This would mean turning on
    // ranges for all subprogram DIEs for mach-o.
    DwarfCompileUnit &U = SkCU ? *SkCU : TheCU;
    if (unsigned NumRanges = TheCU.getRanges().size()) {
      if (NumRanges > 1)
        // A DW_AT_low_pc attribute may also be specified in combination with
        // DW_AT_ranges to specify the default base address for use in
        // location lists (see Section 2.6.2) and range lists (see Section
        // 2.17.3).
        U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0);
      else
        TheCU.setBaseAddress(TheCU.getRanges().front().getStart());
      U.attachRangesOrLowHighPC(U.getUnitDie(), TheCU.takeRanges());
    }
  }

  // Compute DIE offsets and sizes.
  InfoHolder.computeSizeAndOffsets();
  if (useSplitDwarf())
    SkeletonHolder.computeSizeAndOffsets();
}

void DwarfDebug::endSections() {
  // Filter labels by section.
  for (const SymbolCU &SCU : ArangeLabels) {
    if (SCU.Sym->isInSection()) {
      // Make a note of this symbol and it's section.
      const MCSection *Section = &SCU.Sym->getSection();
      if (!Section->getKind().isMetadata())
        SectionMap[Section].push_back(SCU);
    } else {
      // Some symbols (e.g. common/bss on mach-o) can have no section but still
      // appear in the output. This sucks as we rely on sections to build
      // arange spans. We can do it without, but it's icky.
      SectionMap[nullptr].push_back(SCU);
    }
  }

  // Build a list of sections used.
  std::vector<const MCSection *> Sections;
  for (const auto &it : SectionMap) {
    const MCSection *Section = it.first;
    Sections.push_back(Section);
  }

  // Sort the sections into order.
  // This is only done to ensure consistent output order across different runs.
  std::sort(Sections.begin(), Sections.end(), SectionSort);

  // Add terminating symbols for each section.
  for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
    const MCSection *Section = Sections[ID];
    MCSymbol *Sym = nullptr;

    if (Section) {
      // We can't call MCSection::getLabelEndName, as it's only safe to do so
      // if we know the section name up-front. For user-created sections, the
      // resulting label may not be valid to use as a label. (section names can
      // use a greater set of characters on some systems)
      Sym = Asm->GetTempSymbol("debug_end", ID);
      Asm->OutStreamer.SwitchSection(Section);
      Asm->OutStreamer.EmitLabel(Sym);
    }

    // Insert a final terminator.
    SectionMap[Section].push_back(SymbolCU(nullptr, Sym));
  }
}

// Emit all Dwarf sections that should come after the content.
void DwarfDebug::endModule() {
  assert(CurFn == nullptr);
  assert(CurMI == nullptr);

  // If we aren't actually generating debug info (check beginModule -
  // conditionalized on !DisableDebugInfoPrinting and the presence of the
  // llvm.dbg.cu metadata node)
  if (!DwarfInfoSectionSym)
    return;

  // End any existing sections.
  // TODO: Does this need to happen?
  endSections();

  // Finalize the debug info for the module.
  finalizeModuleInfo();

  emitDebugStr();

  // Emit all the DIEs into a debug info section.
  emitDebugInfo();

  // Corresponding abbreviations into a abbrev section.
  emitAbbreviations();

  // Emit info into a debug aranges section.
  if (GenerateARangeSection)
    emitDebugARanges();

  // Emit info into a debug ranges section.
  emitDebugRanges();

  if (useSplitDwarf()) {
    emitDebugStrDWO();
    emitDebugInfoDWO();
    emitDebugAbbrevDWO();
    emitDebugLineDWO();
    emitDebugLocDWO();
    // Emit DWO addresses.
    AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection());
  } else
    // Emit info into a debug loc section.
    emitDebugLoc();

  // Emit info into the dwarf accelerator table sections.
  if (useDwarfAccelTables()) {
    emitAccelNames();
    emitAccelObjC();
    emitAccelNamespaces();
    emitAccelTypes();
  }

  // Emit the pubnames and pubtypes sections if requested.
  if (HasDwarfPubSections) {
    emitDebugPubNames(GenerateGnuPubSections);
    emitDebugPubTypes(GenerateGnuPubSections);
  }

  // clean up.
  SPMap.clear();
  AbstractVariables.clear();
}

// Find abstract variable, if any, associated with Var.
DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV,
                                                     DIVariable &Cleansed) {
  LLVMContext &Ctx = DV->getContext();
  // More then one inlined variable corresponds to one abstract variable.
  // FIXME: This duplication of variables when inlining should probably be
  // removed. It's done to allow each DIVariable to describe its location
  // because the DebugLoc on the dbg.value/declare isn't accurate. We should
  // make it accurate then remove this duplication/cleansing stuff.
  Cleansed = cleanseInlinedVariable(DV, Ctx);
  auto I = AbstractVariables.find(Cleansed);
  if (I != AbstractVariables.end())
    return I->second.get();
  return nullptr;
}

DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV) {
  DIVariable Cleansed;
  return getExistingAbstractVariable(DV, Cleansed);
}

void DwarfDebug::createAbstractVariable(const DIVariable &Var,
                                        LexicalScope *Scope) {
  auto AbsDbgVariable = make_unique<DbgVariable>(Var, DIExpression(), this);
  InfoHolder.addScopeVariable(Scope, AbsDbgVariable.get());
  AbstractVariables[Var] = std::move(AbsDbgVariable);
}

void DwarfDebug::ensureAbstractVariableIsCreated(const DIVariable &DV,
                                                 const MDNode *ScopeNode) {
  DIVariable Cleansed = DV;
  if (getExistingAbstractVariable(DV, Cleansed))
    return;

  createAbstractVariable(Cleansed, LScopes.getOrCreateAbstractScope(ScopeNode));
}

void
DwarfDebug::ensureAbstractVariableIsCreatedIfScoped(const DIVariable &DV,
                                                    const MDNode *ScopeNode) {
  DIVariable Cleansed = DV;
  if (getExistingAbstractVariable(DV, Cleansed))
    return;

  if (LexicalScope *Scope = LScopes.findAbstractScope(ScopeNode))
    createAbstractVariable(Cleansed, Scope);
}

// Collect variable information from side table maintained by MMI.
void DwarfDebug::collectVariableInfoFromMMITable(
    SmallPtrSetImpl<const MDNode *> &Processed) {
  for (const auto &VI : MMI->getVariableDbgInfo()) {
    if (!VI.Var)
      continue;
    Processed.insert(VI.Var);
    LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);

    // If variable scope is not found then skip this variable.
    if (!Scope)
      continue;

    DIVariable DV(VI.Var);
    DIExpression Expr(VI.Expr);
    ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
    ConcreteVariables.push_back(make_unique<DbgVariable>(DV, Expr, this));
    DbgVariable *RegVar = ConcreteVariables.back().get();
    RegVar->setFrameIndex(VI.Slot);
    InfoHolder.addScopeVariable(Scope, RegVar);
  }
}

// Get .debug_loc entry for the instruction range starting at MI.
static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
  const MDNode *Expr = MI->getDebugExpression();
  const MDNode *Var = MI->getDebugVariable();

  assert(MI->getNumOperands() == 4);
  if (MI->getOperand(0).isReg()) {
    MachineLocation MLoc;
    // If the second operand is an immediate, this is a
    // register-indirect address.
    if (!MI->getOperand(1).isImm())
      MLoc.set(MI->getOperand(0).getReg());
    else
      MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
    return DebugLocEntry::Value(Var, Expr, MLoc);
  }
  if (MI->getOperand(0).isImm())
    return DebugLocEntry::Value(Var, Expr, MI->getOperand(0).getImm());
  if (MI->getOperand(0).isFPImm())
    return DebugLocEntry::Value(Var, Expr, MI->getOperand(0).getFPImm());
  if (MI->getOperand(0).isCImm())
    return DebugLocEntry::Value(Var, Expr, MI->getOperand(0).getCImm());

  llvm_unreachable("Unexpected 4-operand DBG_VALUE instruction!");
}

/// Determine whether two variable pieces overlap.
static bool piecesOverlap(DIExpression P1, DIExpression P2) {
  if (!P1.isVariablePiece() || !P2.isVariablePiece())
    return true;
  unsigned l1 = P1.getPieceOffset();
  unsigned l2 = P2.getPieceOffset();
  unsigned r1 = l1 + P1.getPieceSize();
  unsigned r2 = l2 + P2.getPieceSize();
  // True where [l1,r1[ and [r1,r2[ overlap.
  return (l1 < r2) && (l2 < r1);
}

/// Build the location list for all DBG_VALUEs in the function that
/// describe the same variable.  If the ranges of several independent
/// pieces of the same variable overlap partially, split them up and
/// combine the ranges. The resulting DebugLocEntries are will have
/// strict monotonically increasing begin addresses and will never
/// overlap.
//
// Input:
//
//   Ranges History [var, loc, piece ofs size]
// 0 |      [x, (reg0, piece 0, 32)]
// 1 | |    [x, (reg1, piece 32, 32)] <- IsPieceOfPrevEntry
// 2 | |    ...
// 3   |    [clobber reg0]
// 4        [x, (mem, piece 0, 64)] <- overlapping with both previous pieces of x.
//
// Output:
//
// [0-1]    [x, (reg0, piece  0, 32)]
// [1-3]    [x, (reg0, piece  0, 32), (reg1, piece 32, 32)]
// [3-4]    [x, (reg1, piece 32, 32)]
// [4- ]    [x, (mem,  piece  0, 64)]
void
DwarfDebug::buildLocationList(SmallVectorImpl<DebugLocEntry> &DebugLoc,
                              const DbgValueHistoryMap::InstrRanges &Ranges) {
  SmallVector<DebugLocEntry::Value, 4> OpenRanges;

  for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) {
    const MachineInstr *Begin = I->first;
    const MachineInstr *End = I->second;
    assert(Begin->isDebugValue() && "Invalid History entry");

    // Check if a variable is inaccessible in this range.
    if (Begin->getNumOperands() > 1 &&
        Begin->getOperand(0).isReg() && !Begin->getOperand(0).getReg()) {
      OpenRanges.clear();
      continue;
    }

    // If this piece overlaps with any open ranges, truncate them.
    DIExpression DIExpr = Begin->getDebugExpression();
    auto Last = std::remove_if(OpenRanges.begin(), OpenRanges.end(),
                               [&](DebugLocEntry::Value R) {
      return piecesOverlap(DIExpr, R.getExpression());
    });
    OpenRanges.erase(Last, OpenRanges.end());

    const MCSymbol *StartLabel = getLabelBeforeInsn(Begin);
    assert(StartLabel && "Forgot label before DBG_VALUE starting a range!");

    const MCSymbol *EndLabel;
    if (End != nullptr)
      EndLabel = getLabelAfterInsn(End);
    else if (std::next(I) == Ranges.end())
      EndLabel = FunctionEndSym;
    else
      EndLabel = getLabelBeforeInsn(std::next(I)->first);
    assert(EndLabel && "Forgot label after instruction ending a range!");

    DEBUG(dbgs() << "DotDebugLoc: " << *Begin << "\n");

    auto Value = getDebugLocValue(Begin);
    DebugLocEntry Loc(StartLabel, EndLabel, Value);
    bool couldMerge = false;

    // If this is a piece, it may belong to the current DebugLocEntry.
    if (DIExpr.isVariablePiece()) {
      // Add this value to the list of open ranges.
      OpenRanges.push_back(Value);

      // Attempt to add the piece to the last entry.
      if (!DebugLoc.empty())
        if (DebugLoc.back().MergeValues(Loc))
          couldMerge = true;
    }

    if (!couldMerge) {
      // Need to add a new DebugLocEntry. Add all values from still
      // valid non-overlapping pieces.
      if (OpenRanges.size())
        Loc.addValues(OpenRanges);

      DebugLoc.push_back(std::move(Loc));
    }

    // Attempt to coalesce the ranges of two otherwise identical
    // DebugLocEntries.
    auto CurEntry = DebugLoc.rbegin();
    auto PrevEntry = std::next(CurEntry);
    if (PrevEntry != DebugLoc.rend() && PrevEntry->MergeRanges(*CurEntry))
      DebugLoc.pop_back();

    DEBUG({
      dbgs() << CurEntry->getValues().size() << " Values:\n";
      for (auto Value : CurEntry->getValues()) {
        Value.getVariable()->dump();
        Value.getExpression()->dump();
      }
      dbgs() << "-----\n";
    });
  }
}


// Find variables for each lexical scope.
void
DwarfDebug::collectVariableInfo(DwarfCompileUnit &TheCU, DISubprogram SP,
                                SmallPtrSetImpl<const MDNode *> &Processed) {
  // Grab the variable info that was squirreled away in the MMI side-table.
  collectVariableInfoFromMMITable(Processed);

  for (const auto &I : DbgValues) {
    DIVariable DV(I.first);
    if (Processed.count(DV))
      continue;

    // Instruction ranges, specifying where DV is accessible.
    const auto &Ranges = I.second;
    if (Ranges.empty())
      continue;

    LexicalScope *Scope = nullptr;
    if (MDNode *IA = DV.getInlinedAt()) {
      DebugLoc DL = DebugLoc::getFromDILocation(IA);
      Scope = LScopes.findInlinedScope(DebugLoc::get(
          DL.getLine(), DL.getCol(), DV.getContext(), IA));
    } else
      Scope = LScopes.findLexicalScope(DV.getContext());
    // If variable scope is not found then skip this variable.
    if (!Scope)
      continue;

    Processed.insert(DV);
    const MachineInstr *MInsn = Ranges.front().first;
    assert(MInsn->isDebugValue() && "History must begin with debug value");
    ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
    ConcreteVariables.push_back(make_unique<DbgVariable>(MInsn, this));
    DbgVariable *RegVar = ConcreteVariables.back().get();
    InfoHolder.addScopeVariable(Scope, RegVar);

    // Check if the first DBG_VALUE is valid for the rest of the function.
    if (Ranges.size() == 1 && Ranges.front().second == nullptr)
      continue;

    // Handle multiple DBG_VALUE instructions describing one variable.
    RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());

    DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
    DebugLocList &LocList = DotDebugLocEntries.back();
    LocList.CU = &TheCU;
    LocList.Label =
        Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);

    // Build the location list for this variable.
    buildLocationList(LocList.List, Ranges);
  }

  // Collect info for variables that were optimized out.
  DIArray Variables = SP.getVariables();
  for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
    DIVariable DV(Variables.getElement(i));
    assert(DV.isVariable());
    if (!Processed.insert(DV).second)
      continue;
    if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) {
      ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
      DIExpression NoExpr;
      ConcreteVariables.push_back(make_unique<DbgVariable>(DV, NoExpr, this));
      InfoHolder.addScopeVariable(Scope, ConcreteVariables.back().get());
    }
  }
}

// Return Label preceding the instruction.
MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
  MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
  assert(Label && "Didn't insert label before instruction");
  return Label;
}

// Return Label immediately following the instruction.
MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
  return LabelsAfterInsn.lookup(MI);
}

// Process beginning of an instruction.
void DwarfDebug::beginInstruction(const MachineInstr *MI) {
  assert(CurMI == nullptr);
  CurMI = MI;
  // Check if source location changes, but ignore DBG_VALUE locations.
  if (!MI->isDebugValue()) {
    DebugLoc DL = MI->getDebugLoc();
    if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
      unsigned Flags = 0;
      PrevInstLoc = DL;
      if (DL == PrologEndLoc) {
        Flags |= DWARF2_FLAG_PROLOGUE_END;
        PrologEndLoc = DebugLoc();
        Flags |= DWARF2_FLAG_IS_STMT;
      }
      if (DL.getLine() !=
          Asm->OutStreamer.getContext().getCurrentDwarfLoc().getLine())
        Flags |= DWARF2_FLAG_IS_STMT;

      if (!DL.isUnknown()) {
        const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
        recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
      } else
        recordSourceLine(0, 0, nullptr, 0);
    }
  }

  // Insert labels where requested.
  DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
      LabelsBeforeInsn.find(MI);

  // No label needed.
  if (I == LabelsBeforeInsn.end())
    return;

  // Label already assigned.
  if (I->second)
    return;

  if (!PrevLabel) {
    PrevLabel = MMI->getContext().CreateTempSymbol();
    Asm->OutStreamer.EmitLabel(PrevLabel);
  }
  I->second = PrevLabel;
}

// Process end of an instruction.
void DwarfDebug::endInstruction() {
  assert(CurMI != nullptr);
  // Don't create a new label after DBG_VALUE instructions.
  // They don't generate code.
  if (!CurMI->isDebugValue())
    PrevLabel = nullptr;

  DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
      LabelsAfterInsn.find(CurMI);
  CurMI = nullptr;

  // No label needed.
  if (I == LabelsAfterInsn.end())
    return;

  // Label already assigned.
  if (I->second)
    return;

  // We need a label after this instruction.
  if (!PrevLabel) {
    PrevLabel = MMI->getContext().CreateTempSymbol();
    Asm->OutStreamer.EmitLabel(PrevLabel);
  }
  I->second = PrevLabel;
}

// Each LexicalScope has first instruction and last instruction to mark
// beginning and end of a scope respectively. Create an inverse map that list
// scopes starts (and ends) with an instruction. One instruction may start (or
// end) multiple scopes. Ignore scopes that are not reachable.
void DwarfDebug::identifyScopeMarkers() {
  SmallVector<LexicalScope *, 4> WorkList;
  WorkList.push_back(LScopes.getCurrentFunctionScope());
  while (!WorkList.empty()) {
    LexicalScope *S = WorkList.pop_back_val();

    const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
    if (!Children.empty())
      WorkList.append(Children.begin(), Children.end());

    if (S->isAbstractScope())
      continue;

    for (const InsnRange &R : S->getRanges()) {
      assert(R.first && "InsnRange does not have first instruction!");
      assert(R.second && "InsnRange does not have second instruction!");
      requestLabelBeforeInsn(R.first);
      requestLabelAfterInsn(R.second);
    }
  }
}

static DebugLoc findPrologueEndLoc(const MachineFunction *MF) {
  // First known non-DBG_VALUE and non-frame setup location marks
  // the beginning of the function body.
  for (const auto &MBB : *MF)
    for (const auto &MI : MBB)
      if (!MI.isDebugValue() && !MI.getFlag(MachineInstr::FrameSetup) &&
        !MI.getDebugLoc().isUnknown()) {
        // Did the target forget to set the FrameSetup flag for CFI insns?
        assert(!MI.isCFIInstruction() &&
               "First non-frame-setup instruction is a CFI instruction.");
        return MI.getDebugLoc();
      }
  return DebugLoc();
}

// Gather pre-function debug information.  Assumes being called immediately
// after the function entry point has been emitted.
void DwarfDebug::beginFunction(const MachineFunction *MF) {
  CurFn = MF;

  // If there's no debug info for the function we're not going to do anything.
  if (!MMI->hasDebugInfo())
    return;

  auto DI = FunctionDIs.find(MF->getFunction());
  if (DI == FunctionDIs.end())
    return;

  // Grab the lexical scopes for the function, if we don't have any of those
  // then we're not going to be able to do anything.
  LScopes.initialize(*MF);
  if (LScopes.empty())
    return;

  assert(DbgValues.empty() && "DbgValues map wasn't cleaned!");

  // Make sure that each lexical scope will have a begin/end label.
  identifyScopeMarkers();

  // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
  // belongs to so that we add to the correct per-cu line table in the
  // non-asm case.
  LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
  // FnScope->getScopeNode() and DI->second should represent the same function,
  // though they may not be the same MDNode due to inline functions merged in
  // LTO where the debug info metadata still differs (either due to distinct
  // written differences - two versions of a linkonce_odr function
  // written/copied into two separate files, or some sub-optimal metadata that
  // isn't structurally identical (see: file path/name info from clang, which
  // includes the directory of the cpp file being built, even when the file name
  // is absolute (such as an <> lookup header)))
  DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
  assert(TheCU && "Unable to find compile unit!");
  if (Asm->OutStreamer.hasRawTextSupport())
    // Use a single line table if we are generating assembly.
    Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
  else
    Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());

  // Emit a label for the function so that we have a beginning address.
  FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
  // Assumes in correct section after the entry point.
  Asm->OutStreamer.EmitLabel(FunctionBeginSym);

  // Calculate history for local variables.
  calculateDbgValueHistory(MF, Asm->TM.getSubtargetImpl()->getRegisterInfo(),
                           DbgValues);

  // Request labels for the full history.
  for (const auto &I : DbgValues) {
    const auto &Ranges = I.second;
    if (Ranges.empty())
      continue;

    // The first mention of a function argument gets the FunctionBeginSym
    // label, so arguments are visible when breaking at function entry.
    DIVariable DIVar(Ranges.front().first->getDebugVariable());
    if (DIVar.isVariable() && DIVar.getTag() == dwarf::DW_TAG_arg_variable &&
        getDISubprogram(DIVar.getContext()).describes(MF->getFunction())) {
      LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym;
      if (Ranges.front().first->getDebugExpression().isVariablePiece()) {
        // Mark all non-overlapping initial pieces.
        for (auto I = Ranges.begin(); I != Ranges.end(); ++I) {
          DIExpression Piece = I->first->getDebugExpression();
          if (std::all_of(Ranges.begin(), I,
                          [&](DbgValueHistoryMap::InstrRange Pred) {
                return !piecesOverlap(Piece, Pred.first->getDebugExpression());
              }))
            LabelsBeforeInsn[I->first] = FunctionBeginSym;
          else
            break;
        }
      }
    }

    for (const auto &Range : Ranges) {
      requestLabelBeforeInsn(Range.first);
      if (Range.second)
        requestLabelAfterInsn(Range.second);
    }
  }

  PrevInstLoc = DebugLoc();
  PrevLabel = FunctionBeginSym;

  // Record beginning of function.
  PrologEndLoc = findPrologueEndLoc(MF);
  if (!PrologEndLoc.isUnknown()) {
    DebugLoc FnStartDL =
        PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
    recordSourceLine(
        FnStartDL.getLine(), FnStartDL.getCol(),
        FnStartDL.getScope(MF->getFunction()->getContext()),
        // We'd like to list the prologue as "not statements" but GDB behaves
        // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
        DWARF2_FLAG_IS_STMT);
  }
}

// Gather and emit post-function debug information.
void DwarfDebug::endFunction(const MachineFunction *MF) {
  assert(CurFn == MF &&
      "endFunction should be called with the same function as beginFunction");

  if (!MMI->hasDebugInfo() || LScopes.empty() ||
      !FunctionDIs.count(MF->getFunction())) {
    // If we don't have a lexical scope for this function then there will
    // be a hole in the range information. Keep note of this by setting the
    // previously used section to nullptr.
    PrevCU = nullptr;
    CurFn = nullptr;
    return;
  }

  // Define end label for subprogram.
  FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
  // Assumes in correct section after the entry point.
  Asm->OutStreamer.EmitLabel(FunctionEndSym);

  // Set DwarfDwarfCompileUnitID in MCContext to default value.
  Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);

  LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
  DISubprogram SP(FnScope->getScopeNode());
  DwarfCompileUnit &TheCU = *SPMap.lookup(SP);

  SmallPtrSet<const MDNode *, 16> ProcessedVars;
  collectVariableInfo(TheCU, SP, ProcessedVars);

  // Add the range of this function to the list of ranges for the CU.
  TheCU.addRange(RangeSpan(FunctionBeginSym, FunctionEndSym));

  // Under -gmlt, skip building the subprogram if there are no inlined
  // subroutines inside it.
  if (TheCU.getCUNode().getEmissionKind() == DIBuilder::LineTablesOnly &&
      LScopes.getAbstractScopesList().empty() && !IsDarwin) {
    assert(InfoHolder.getScopeVariables().empty());
    assert(DbgValues.empty());
    // FIXME: This wouldn't be true in LTO with a -g (with inlining) CU followed
    // by a -gmlt CU. Add a test and remove this assertion.
    assert(AbstractVariables.empty());
    LabelsBeforeInsn.clear();
    LabelsAfterInsn.clear();
    PrevLabel = nullptr;
    CurFn = nullptr;
    return;
  }

#ifndef NDEBUG
  size_t NumAbstractScopes = LScopes.getAbstractScopesList().size();
#endif
  // Construct abstract scopes.
  for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
    DISubprogram SP(AScope->getScopeNode());
    assert(SP.isSubprogram());
    // Collect info for variables that were optimized out.
    DIArray Variables = SP.getVariables();
    for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
      DIVariable DV(Variables.getElement(i));
      assert(DV && DV.isVariable());
      if (!ProcessedVars.insert(DV).second)
        continue;
      ensureAbstractVariableIsCreated(DV, DV.getContext());
      assert(LScopes.getAbstractScopesList().size() == NumAbstractScopes
             && "ensureAbstractVariableIsCreated inserted abstract scopes");
    }
    constructAbstractSubprogramScopeDIE(AScope);
  }

  TheCU.constructSubprogramScopeDIE(FnScope);
  if (auto *SkelCU = TheCU.getSkeleton())
    if (!LScopes.getAbstractScopesList().empty())
      SkelCU->constructSubprogramScopeDIE(FnScope);

  // Clear debug info
  // Ownership of DbgVariables is a bit subtle - ScopeVariables owns all the
  // DbgVariables except those that are also in AbstractVariables (since they
  // can be used cross-function)
  InfoHolder.getScopeVariables().clear();
  DbgValues.clear();
  LabelsBeforeInsn.clear();
  LabelsAfterInsn.clear();
  PrevLabel = nullptr;
  CurFn = nullptr;
}

// Register a source line with debug info. Returns the  unique label that was
// emitted and which provides correspondence to the source line list.
void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
                                  unsigned Flags) {
  StringRef Fn;
  StringRef Dir;
  unsigned Src = 1;
  unsigned Discriminator = 0;
  if (DIScope Scope = DIScope(S)) {
    assert(Scope.isScope());
    Fn = Scope.getFilename();
    Dir = Scope.getDirectory();
    if (Scope.isLexicalBlockFile())
      Discriminator = DILexicalBlockFile(S).getDiscriminator();

    unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
    Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
              .getOrCreateSourceID(Fn, Dir);
  }
  Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
                                         Discriminator, Fn);
}

//===----------------------------------------------------------------------===//
// Emit Methods
//===----------------------------------------------------------------------===//

// Emit initial Dwarf sections with a label at the start of each one.
void DwarfDebug::emitSectionLabels() {
  const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();

  // Dwarf sections base addresses.
  DwarfInfoSectionSym =
      emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
  if (useSplitDwarf()) {
    DwarfInfoDWOSectionSym =
        emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
    DwarfTypesDWOSectionSym =
        emitSectionSym(Asm, TLOF.getDwarfTypesDWOSection(), "section_types_dwo");
  }
  DwarfAbbrevSectionSym =
      emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
  if (useSplitDwarf())
    DwarfAbbrevDWOSectionSym = emitSectionSym(
        Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
  if (GenerateARangeSection)
    emitSectionSym(Asm, TLOF.getDwarfARangesSection());

  DwarfLineSectionSym =
      emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
  if (GenerateGnuPubSections) {
    DwarfGnuPubNamesSectionSym =
        emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
    DwarfGnuPubTypesSectionSym =
        emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
  } else if (HasDwarfPubSections) {
    emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
    emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
  }

  DwarfStrSectionSym =
      emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
  if (useSplitDwarf()) {
    DwarfStrDWOSectionSym =
        emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
    DwarfAddrSectionSym =
        emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
    DwarfDebugLocSectionSym =
        emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
  } else
    DwarfDebugLocSectionSym =
        emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
  DwarfDebugRangeSectionSym =
      emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
}

// Recursively emits a debug information entry.
void DwarfDebug::emitDIE(DIE &Die) {
  // Get the abbreviation for this DIE.
  const DIEAbbrev &Abbrev = Die.getAbbrev();

  // Emit the code (index) for the abbreviation.
  if (Asm->isVerbose())
    Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
                                "] 0x" + Twine::utohexstr(Die.getOffset()) +
                                ":0x" + Twine::utohexstr(Die.getSize()) + " " +
                                dwarf::TagString(Abbrev.getTag()));
  Asm->EmitULEB128(Abbrev.getNumber());

  const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
  const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();

  // Emit the DIE attribute values.
  for (unsigned i = 0, N = Values.size(); i < N; ++i) {
    dwarf::Attribute Attr = AbbrevData[i].getAttribute();
    dwarf::Form Form = AbbrevData[i].getForm();
    assert(Form && "Too many attributes for DIE (check abbreviation)");

    if (Asm->isVerbose()) {
      Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
      if (Attr == dwarf::DW_AT_accessibility)
        Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
            cast<DIEInteger>(Values[i])->getValue()));
    }

    // Emit an attribute using the defined form.
    Values[i]->EmitValue(Asm, Form);
  }

  // Emit the DIE children if any.
  if (Abbrev.hasChildren()) {
    for (auto &Child : Die.getChildren())
      emitDIE(*Child);

    Asm->OutStreamer.AddComment("End Of Children Mark");
    Asm->EmitInt8(0);
  }
}

// Emit the debug info section.
void DwarfDebug::emitDebugInfo() {
  DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;

  Holder.emitUnits(DwarfAbbrevSectionSym);
}

// Emit the abbreviation section.
void DwarfDebug::emitAbbreviations() {
  DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;

  Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
}

// Emit the last address of the section and the end of the line matrix.
void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
  // Define last address of section.
  Asm->OutStreamer.AddComment("Extended Op");
  Asm->EmitInt8(0);

  Asm->OutStreamer.AddComment("Op size");
  Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
  Asm->OutStreamer.AddComment("DW_LNE_set_address");
  Asm->EmitInt8(dwarf::DW_LNE_set_address);

  Asm->OutStreamer.AddComment("Section end label");

  Asm->OutStreamer.EmitSymbolValue(
      Asm->GetTempSymbol("section_end", SectionEnd),
      Asm->getDataLayout().getPointerSize());

  // Mark end of matrix.
  Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
  Asm->EmitInt8(0);
  Asm->EmitInt8(1);
  Asm->EmitInt8(1);
}

void DwarfDebug::emitAccel(DwarfAccelTable &Accel, const MCSection *Section,
                           StringRef TableName, StringRef SymName) {
  Accel.FinalizeTable(Asm, TableName);
  Asm->OutStreamer.SwitchSection(Section);
  auto *SectionBegin = Asm->GetTempSymbol(SymName);
  Asm->OutStreamer.EmitLabel(SectionBegin);

  // Emit the full data.
  Accel.Emit(Asm, SectionBegin, this, DwarfStrSectionSym);
}

// Emit visible names into a hashed accelerator table section.
void DwarfDebug::emitAccelNames() {
  emitAccel(AccelNames, Asm->getObjFileLowering().getDwarfAccelNamesSection(),
            "Names", "names_begin");
}

// Emit objective C classes and categories into a hashed accelerator table
// section.
void DwarfDebug::emitAccelObjC() {
  emitAccel(AccelObjC, Asm->getObjFileLowering().getDwarfAccelObjCSection(),
            "ObjC", "objc_begin");
}

// Emit namespace dies into a hashed accelerator table.
void DwarfDebug::emitAccelNamespaces() {
  emitAccel(AccelNamespace,
            Asm->getObjFileLowering().getDwarfAccelNamespaceSection(),
            "namespac", "namespac_begin");
}

// Emit type dies into a hashed accelerator table.
void DwarfDebug::emitAccelTypes() {
  emitAccel(AccelTypes, Asm->getObjFileLowering().getDwarfAccelTypesSection(),
            "types", "types_begin");
}

// Public name handling.
// The format for the various pubnames:
//
// dwarf pubnames - offset/name pairs where the offset is the offset into the CU
// for the DIE that is named.
//
// gnu pubnames - offset/index value/name tuples where the offset is the offset
// into the CU and the index value is computed according to the type of value
// for the DIE that is named.
//
// For type units the offset is the offset of the skeleton DIE. For split dwarf
// it's the offset within the debug_info/debug_types dwo section, however, the
// reference in the pubname header doesn't change.

/// computeIndexValue - Compute the gdb index value for the DIE and CU.
static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
                                                        const DIE *Die) {
  dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;

  // We could have a specification DIE that has our most of our knowledge,
  // look for that now.
  DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
  if (SpecVal) {
    DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
    if (SpecDIE.findAttribute(dwarf::DW_AT_external))
      Linkage = dwarf::GIEL_EXTERNAL;
  } else if (Die->findAttribute(dwarf::DW_AT_external))
    Linkage = dwarf::GIEL_EXTERNAL;

  switch (Die->getTag()) {
  case dwarf::DW_TAG_class_type:
  case dwarf::DW_TAG_structure_type:
  case dwarf::DW_TAG_union_type:
  case dwarf::DW_TAG_enumeration_type:
    return dwarf::PubIndexEntryDescriptor(
        dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
                              ? dwarf::GIEL_STATIC
                              : dwarf::GIEL_EXTERNAL);
  case dwarf::DW_TAG_typedef:
  case dwarf::DW_TAG_base_type:
  case dwarf::DW_TAG_subrange_type:
    return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
  case dwarf::DW_TAG_namespace:
    return dwarf::GIEK_TYPE;
  case dwarf::DW_TAG_subprogram:
    return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
  case dwarf::DW_TAG_constant:
  case dwarf::DW_TAG_variable:
    return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
  case dwarf::DW_TAG_enumerator:
    return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
                                          dwarf::GIEL_STATIC);
  default:
    return dwarf::GIEK_NONE;
  }
}

/// emitDebugPubNames - Emit visible names into a debug pubnames section.
///
void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
  const MCSection *PSec =
      GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
               : Asm->getObjFileLowering().getDwarfPubNamesSection();

  emitDebugPubSection(GnuStyle, PSec, "Names",
                      &DwarfCompileUnit::getGlobalNames);
}

void DwarfDebug::emitDebugPubSection(
    bool GnuStyle, const MCSection *PSec, StringRef Name,
    const StringMap<const DIE *> &(DwarfCompileUnit::*Accessor)() const) {
  for (const auto &NU : CUMap) {
    DwarfCompileUnit *TheU = NU.second;

    const auto &Globals = (TheU->*Accessor)();

    if (Globals.empty())
      continue;

    if (auto *Skeleton = TheU->getSkeleton())
      TheU = Skeleton;
    unsigned ID = TheU->getUniqueID();

    // Start the dwarf pubnames section.
    Asm->OutStreamer.SwitchSection(PSec);

    // Emit the header.
    Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
    MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
    MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
    Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);

    Asm->OutStreamer.EmitLabel(BeginLabel);

    Asm->OutStreamer.AddComment("DWARF Version");
    Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);

    Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
    Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());

    Asm->OutStreamer.AddComment("Compilation Unit Length");
    Asm->EmitInt32(TheU->getLength());

    // Emit the pubnames for this compilation unit.
    for (const auto &GI : Globals) {
      const char *Name = GI.getKeyData();
      const DIE *Entity = GI.second;

      Asm->OutStreamer.AddComment("DIE offset");
      Asm->EmitInt32(Entity->getOffset());

      if (GnuStyle) {
        dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
        Asm->OutStreamer.AddComment(
            Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
            dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
        Asm->EmitInt8(Desc.toBits());
      }

      Asm->OutStreamer.AddComment("External Name");
      Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
    }

    Asm->OutStreamer.AddComment("End Mark");
    Asm->EmitInt32(0);
    Asm->OutStreamer.EmitLabel(EndLabel);
  }
}

void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
  const MCSection *PSec =
      GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
               : Asm->getObjFileLowering().getDwarfPubTypesSection();

  emitDebugPubSection(GnuStyle, PSec, "Types",
                      &DwarfCompileUnit::getGlobalTypes);
}

// Emit visible names into a debug str section.
void DwarfDebug::emitDebugStr() {
  DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
  Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
}

/// Emits an optimal (=sorted) sequence of DW_OP_pieces.
void DwarfDebug::emitLocPieces(ByteStreamer &Streamer,
                               const DITypeIdentifierMap &Map,
                               ArrayRef<DebugLocEntry::Value> Values) {
  assert(std::all_of(Values.begin(), Values.end(), [](DebugLocEntry::Value P) {
        return P.isVariablePiece();
      }) && "all values are expected to be pieces");
  assert(std::is_sorted(Values.begin(), Values.end()) &&
         "pieces are expected to be sorted");

  unsigned Offset = 0;
  for (auto Piece : Values) {
    const unsigned SizeOfByte = 8;
    DIExpression Expr = Piece.getExpression();
    unsigned PieceOffset = Expr.getPieceOffset();
    unsigned PieceSize = Expr.getPieceSize();
    assert(Offset <= PieceOffset && "overlapping or duplicate pieces");
    if (Offset < PieceOffset) {
      // The DWARF spec seriously mandates pieces with no locations for gaps.
      Asm->EmitDwarfOpPiece(Streamer, (PieceOffset-Offset)*SizeOfByte);
      Offset += PieceOffset-Offset;
    }
    Offset += PieceSize;

#ifndef NDEBUG
    DIVariable Var = Piece.getVariable();
    assert(!Var.isIndirect() && "indirect address for piece");
    unsigned VarSize = Var.getSizeInBits(Map);
    assert(PieceSize+PieceOffset <= VarSize/SizeOfByte
           && "piece is larger than or outside of variable");
    assert(PieceSize*SizeOfByte != VarSize
           && "piece covers entire variable");
#endif

    emitDebugLocValue(Streamer, Piece, PieceOffset*SizeOfByte);
  }
}


void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
                                   const DebugLocEntry &Entry) {
  const DebugLocEntry::Value Value = Entry.getValues()[0];
  if (Value.isVariablePiece())
    // Emit all pieces that belong to the same variable and range.
    return emitLocPieces(Streamer, TypeIdentifierMap, Entry.getValues());

  assert(Entry.getValues().size() == 1 && "only pieces may have >1 value");
  emitDebugLocValue(Streamer, Value);
}

void DwarfDebug::emitDebugLocValue(ByteStreamer &Streamer,
                                   const DebugLocEntry::Value &Value,
                                   unsigned PieceOffsetInBits) {
  DIVariable DV = Value.getVariable();
  DebugLocDwarfExpression DwarfExpr(*Asm, Streamer);

  // Regular entry.
  if (Value.isInt()) {
    DIBasicType BTy(resolve(DV.getType()));
    if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
                         BTy.getEncoding() == dwarf::DW_ATE_signed_char))
      DwarfExpr.AddSignedConstant(Value.getInt());
    else
      DwarfExpr.AddUnsignedConstant(Value.getInt());
  } else if (Value.isLocation()) {
    MachineLocation Loc = Value.getLoc();
    DIExpression Expr = Value.getExpression();
    if (!Expr || (Expr.getNumElements() == 0))
      // Regular entry.
      Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
    else {
      // Complex address entry.
      if (Loc.getOffset()) {
        DwarfExpr.AddMachineRegIndirect(Loc.getReg(), Loc.getOffset());
        DwarfExpr.AddExpression(Expr, PieceOffsetInBits);
      } else
        DwarfExpr.AddMachineRegExpression(Expr, Loc.getReg(),
                                          PieceOffsetInBits);
      if (DV.isIndirect())
        DwarfExpr.EmitOp(dwarf::DW_OP_deref);
    }
  }
  // else ... ignore constant fp. There is not any good way to
  // to represent them here in dwarf.
  // FIXME: ^
}

void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
  Asm->OutStreamer.AddComment("Loc expr size");
  MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
  MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
  Asm->EmitLabelDifference(end, begin, 2);
  Asm->OutStreamer.EmitLabel(begin);
  // Emit the entry.
  APByteStreamer Streamer(*Asm);
  emitDebugLocEntry(Streamer, Entry);
  // Close the range.
  Asm->OutStreamer.EmitLabel(end);
}

// Emit locations into the debug loc section.
void DwarfDebug::emitDebugLoc() {
  // Start the dwarf loc section.
  Asm->OutStreamer.SwitchSection(
      Asm->getObjFileLowering().getDwarfLocSection());
  unsigned char Size = Asm->getDataLayout().getPointerSize();
  for (const auto &DebugLoc : DotDebugLocEntries) {
    Asm->OutStreamer.EmitLabel(DebugLoc.Label);
    const DwarfCompileUnit *CU = DebugLoc.CU;
    for (const auto &Entry : DebugLoc.List) {
      // Set up the range. This range is relative to the entry point of the
      // compile unit. This is a hard coded 0 for low_pc when we're emitting
      // ranges, or the DW_AT_low_pc on the compile unit otherwise.
      if (auto *Base = CU->getBaseAddress()) {
        Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
        Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
      } else {
        Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
        Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
      }

      emitDebugLocEntryLocation(Entry);
    }
    Asm->OutStreamer.EmitIntValue(0, Size);
    Asm->OutStreamer.EmitIntValue(0, Size);
  }
}

void DwarfDebug::emitDebugLocDWO() {
  Asm->OutStreamer.SwitchSection(
      Asm->getObjFileLowering().getDwarfLocDWOSection());
  for (const auto &DebugLoc : DotDebugLocEntries) {
    Asm->OutStreamer.EmitLabel(DebugLoc.Label);
    for (const auto &Entry : DebugLoc.List) {
      // Just always use start_length for now - at least that's one address
      // rather than two. We could get fancier and try to, say, reuse an
      // address we know we've emitted elsewhere (the start of the function?
      // The start of the CU or CU subrange that encloses this range?)
      Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
      unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
      Asm->EmitULEB128(idx);
      Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);

      emitDebugLocEntryLocation(Entry);
    }
    Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
  }
}

struct ArangeSpan {
  const MCSymbol *Start, *End;
};

// Emit a debug aranges section, containing a CU lookup for any
// address we can tie back to a CU.
void DwarfDebug::emitDebugARanges() {
  // Start the dwarf aranges section.
  Asm->OutStreamer.SwitchSection(
      Asm->getObjFileLowering().getDwarfARangesSection());

  typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;

  SpansType Spans;

  // Build a list of sections used.
  std::vector<const MCSection *> Sections;
  for (const auto &it : SectionMap) {
    const MCSection *Section = it.first;
    Sections.push_back(Section);
  }

  // Sort the sections into order.
  // This is only done to ensure consistent output order across different runs.
  std::sort(Sections.begin(), Sections.end(), SectionSort);

  // Build a set of address spans, sorted by CU.
  for (const MCSection *Section : Sections) {
    SmallVector<SymbolCU, 8> &List = SectionMap[Section];
    if (List.size() < 2)
      continue;

    // Sort the symbols by offset within the section.
    std::sort(List.begin(), List.end(),
              [&](const SymbolCU &A, const SymbolCU &B) {
      unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
      unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;

      // Symbols with no order assigned should be placed at the end.
      // (e.g. section end labels)
      if (IA == 0)
        return false;
      if (IB == 0)
        return true;
      return IA < IB;
    });

    // If we have no section (e.g. common), just write out
    // individual spans for each symbol.
    if (!Section) {
      for (const SymbolCU &Cur : List) {
        ArangeSpan Span;
        Span.Start = Cur.Sym;
        Span.End = nullptr;
        if (Cur.CU)
          Spans[Cur.CU].push_back(Span);
      }
    } else {
      // Build spans between each label.
      const MCSymbol *StartSym = List[0].Sym;
      for (size_t n = 1, e = List.size(); n < e; n++) {
        const SymbolCU &Prev = List[n - 1];
        const SymbolCU &Cur = List[n];

        // Try and build the longest span we can within the same CU.
        if (Cur.CU != Prev.CU) {
          ArangeSpan Span;
          Span.Start = StartSym;
          Span.End = Cur.Sym;
          Spans[Prev.CU].push_back(Span);
          StartSym = Cur.Sym;
        }
      }
    }
  }

  unsigned PtrSize = Asm->getDataLayout().getPointerSize();

  // Build a list of CUs used.
  std::vector<DwarfCompileUnit *> CUs;
  for (const auto &it : Spans) {
    DwarfCompileUnit *CU = it.first;
    CUs.push_back(CU);
  }

  // Sort the CU list (again, to ensure consistent output order).
  std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
    return A->getUniqueID() < B->getUniqueID();
  });

  // Emit an arange table for each CU we used.
  for (DwarfCompileUnit *CU : CUs) {
    std::vector<ArangeSpan> &List = Spans[CU];

    // Describe the skeleton CU's offset and length, not the dwo file's.
    if (auto *Skel = CU->getSkeleton())
      CU = Skel;

    // Emit size of content not including length itself.
    unsigned ContentSize =
        sizeof(int16_t) + // DWARF ARange version number
        sizeof(int32_t) + // Offset of CU in the .debug_info section
        sizeof(int8_t) +  // Pointer Size (in bytes)
        sizeof(int8_t);   // Segment Size (in bytes)

    unsigned TupleSize = PtrSize * 2;

    // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
    unsigned Padding =
        OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);

    ContentSize += Padding;
    ContentSize += (List.size() + 1) * TupleSize;

    // For each compile unit, write the list of spans it covers.
    Asm->OutStreamer.AddComment("Length of ARange Set");
    Asm->EmitInt32(ContentSize);
    Asm->OutStreamer.AddComment("DWARF Arange version number");
    Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
    Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
    Asm->EmitSectionOffset(CU->getLabelBegin(), CU->getSectionSym());
    Asm->OutStreamer.AddComment("Address Size (in bytes)");
    Asm->EmitInt8(PtrSize);
    Asm->OutStreamer.AddComment("Segment Size (in bytes)");
    Asm->EmitInt8(0);

    Asm->OutStreamer.EmitFill(Padding, 0xff);

    for (const ArangeSpan &Span : List) {
      Asm->EmitLabelReference(Span.Start, PtrSize);

      // Calculate the size as being from the span start to it's end.
      if (Span.End) {
        Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
      } else {
        // For symbols without an end marker (e.g. common), we
        // write a single arange entry containing just that one symbol.
        uint64_t Size = SymSize[Span.Start];
        if (Size == 0)
          Size = 1;

        Asm->OutStreamer.EmitIntValue(Size, PtrSize);
      }
    }

    Asm->OutStreamer.AddComment("ARange terminator");
    Asm->OutStreamer.EmitIntValue(0, PtrSize);
    Asm->OutStreamer.EmitIntValue(0, PtrSize);
  }
}

// Emit visible names into a debug ranges section.
void DwarfDebug::emitDebugRanges() {
  // Start the dwarf ranges section.
  Asm->OutStreamer.SwitchSection(
      Asm->getObjFileLowering().getDwarfRangesSection());

  // Size for our labels.
  unsigned char Size = Asm->getDataLayout().getPointerSize();

  // Grab the specific ranges for the compile units in the module.
  for (const auto &I : CUMap) {
    DwarfCompileUnit *TheCU = I.second;

    if (auto *Skel = TheCU->getSkeleton())
      TheCU = Skel;

    // Iterate over the misc ranges for the compile units in the module.
    for (const RangeSpanList &List : TheCU->getRangeLists()) {
      // Emit our symbol so we can find the beginning of the range.
      Asm->OutStreamer.EmitLabel(List.getSym());

      for (const RangeSpan &Range : List.getRanges()) {
        const MCSymbol *Begin = Range.getStart();
        const MCSymbol *End = Range.getEnd();
        assert(Begin && "Range without a begin symbol?");
        assert(End && "Range without an end symbol?");
        if (auto *Base = TheCU->getBaseAddress()) {
          Asm->EmitLabelDifference(Begin, Base, Size);
          Asm->EmitLabelDifference(End, Base, Size);
        } else {
          Asm->OutStreamer.EmitSymbolValue(Begin, Size);
          Asm->OutStreamer.EmitSymbolValue(End, Size);
        }
      }

      // And terminate the list with two 0 values.
      Asm->OutStreamer.EmitIntValue(0, Size);
      Asm->OutStreamer.EmitIntValue(0, Size);
    }
  }
}

// DWARF5 Experimental Separate Dwarf emitters.

void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
                                  std::unique_ptr<DwarfUnit> NewU) {
  NewU->addString(Die, dwarf::DW_AT_GNU_dwo_name,
                  U.getCUNode().getSplitDebugFilename());

  if (!CompilationDir.empty())
    NewU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);

  addGnuPubAttributes(*NewU, Die);

  SkeletonHolder.addUnit(std::move(NewU));
}

// This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
// DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
// DW_AT_addr_base, DW_AT_ranges_base.
DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {

  auto OwnedUnit = make_unique<DwarfCompileUnit>(
      CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
  DwarfCompileUnit &NewCU = *OwnedUnit;
  NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
                    DwarfInfoSectionSym);

  NewCU.initStmtList(DwarfLineSectionSym);

  initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));

  return NewCU;
}

// Emit the .debug_info.dwo section for separated dwarf. This contains the
// compile units that would normally be in debug_info.
void DwarfDebug::emitDebugInfoDWO() {
  assert(useSplitDwarf() && "No split dwarf debug info?");
  // Don't pass an abbrev symbol, using a constant zero instead so as not to
  // emit relocations into the dwo file.
  InfoHolder.emitUnits(/* AbbrevSymbol */ nullptr);
}

// Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
// abbreviations for the .debug_info.dwo section.
void DwarfDebug::emitDebugAbbrevDWO() {
  assert(useSplitDwarf() && "No split dwarf?");
  InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
}

void DwarfDebug::emitDebugLineDWO() {
  assert(useSplitDwarf() && "No split dwarf?");
  Asm->OutStreamer.SwitchSection(
      Asm->getObjFileLowering().getDwarfLineDWOSection());
  SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
}

// Emit the .debug_str.dwo section for separated dwarf. This contains the
// string section and is identical in format to traditional .debug_str
// sections.
void DwarfDebug::emitDebugStrDWO() {
  assert(useSplitDwarf() && "No split dwarf?");
  const MCSection *OffSec =
      Asm->getObjFileLowering().getDwarfStrOffDWOSection();
  InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
                         OffSec);
}

MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
  if (!useSplitDwarf())
    return nullptr;
  if (SingleCU)
    SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
  return &SplitTypeUnitFileTable;
}

static uint64_t makeTypeSignature(StringRef Identifier) {
  MD5 Hash;
  Hash.update(Identifier);
  // ... take the least significant 8 bytes and return those. Our MD5
  // implementation always returns its results in little endian, swap bytes
  // appropriately.
  MD5::MD5Result Result;
  Hash.final(Result);
  return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
}

void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
                                      StringRef Identifier, DIE &RefDie,
                                      DICompositeType CTy) {
  // Fast path if we're building some type units and one has already used the
  // address pool we know we're going to throw away all this work anyway, so
  // don't bother building dependent types.
  if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
    return;

  const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
  if (TU) {
    CU.addDIETypeSignature(RefDie, *TU);
    return;
  }

  bool TopLevelType = TypeUnitsUnderConstruction.empty();
  AddrPool.resetUsedFlag();

  auto OwnedUnit = make_unique<DwarfTypeUnit>(
      InfoHolder.getUnits().size() + TypeUnitsUnderConstruction.size(), CU, Asm,
      this, &InfoHolder, getDwoLineTable(CU));
  DwarfTypeUnit &NewTU = *OwnedUnit;
  DIE &UnitDie = NewTU.getUnitDie();
  TU = &NewTU;
  TypeUnitsUnderConstruction.push_back(
      std::make_pair(std::move(OwnedUnit), CTy));

  NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
                CU.getLanguage());

  uint64_t Signature = makeTypeSignature(Identifier);
  NewTU.setTypeSignature(Signature);

  if (useSplitDwarf())
    NewTU.initSection(Asm->getObjFileLowering().getDwarfTypesDWOSection());
  else {
    CU.applyStmtList(UnitDie);
    NewTU.initSection(
        Asm->getObjFileLowering().getDwarfTypesSection(Signature));
  }

  NewTU.setType(NewTU.createTypeDIE(CTy));

  if (TopLevelType) {
    auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
    TypeUnitsUnderConstruction.clear();

    // Types referencing entries in the address table cannot be placed in type
    // units.
    if (AddrPool.hasBeenUsed()) {

      // Remove all the types built while building this type.
      // This is pessimistic as some of these types might not be dependent on
      // the type that used an address.
      for (const auto &TU : TypeUnitsToAdd)
        DwarfTypeUnits.erase(TU.second);

      // Construct this type in the CU directly.
      // This is inefficient because all the dependent types will be rebuilt
      // from scratch, including building them in type units, discovering that
      // they depend on addresses, throwing them out and rebuilding them.
      CU.constructTypeDIE(RefDie, CTy);
      return;
    }

    // If the type wasn't dependent on fission addresses, finish adding the type
    // and all its dependent types.
    for (auto &TU : TypeUnitsToAdd)
      InfoHolder.addUnit(std::move(TU.first));
  }
  CU.addDIETypeSignature(RefDie, NewTU);
}

// Accelerator table mutators - add each name along with its companion
// DIE to the proper table while ensuring that the name that we're going
// to reference is in the string table. We do this since the names we
// add may not only be identical to the names in the DIE.
void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
  if (!useDwarfAccelTables())
    return;
  AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
                     &Die);
}

void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
  if (!useDwarfAccelTables())
    return;
  AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
                    &Die);
}

void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
  if (!useDwarfAccelTables())
    return;
  AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
                         &Die);
}

void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
  if (!useDwarfAccelTables())
    return;
  AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
                     &Die);
}