Apple M1 Microarchitecture Research by Dougall Johnson

Firestorm: Overview | Base Instructions | SIMD and FP Instructions
Icestorm:  Overview | Base Instructions | SIMD and FP Instructions

SHSUB (vector, 4H)

Test 1: uops

Code:

  shsub v0.4h, v0.4h, v1.4h
  movi v0.16b, 1
  movi v1.16b, 2

(no loop instructions)

1000 unrolls and 1 iteration

Retires: 1.000

Issues: 1.000

Integer unit issues: 0.000

Load/store unit issues: 0.000

SIMD/FP unit issues: 1.000

retire (01)cycle (02)031e3f4e51inst issue (52)~issue fp/simd (54)~dispatch fp/simd (57)huge thing fp/simd (5b)60696d6edispatch stall (70)scheduler rewind (75)scheduler stall (76)~dispatch op (78)~map op fp/simd (7e)~map lookup fp/simd (81)8283pipeline redirect (84)85inst all (8c)inst neon or fp (9a)a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)f5f6f7f8fd
100420371606116872510001000100026468002018203720371572318951000100020002037203711100110000073216221787100020382038203820382038
100420371506116872510001000100026468002018203720371572318951000100020002037203711100110000073216221787100020382038203820382038
1004203715031016872510001000100026468002018203720371572318951000100020002037203711100110000373216221787100020382038203820382038
100420371506116872510001000100026468002018203720371572318951000100020002037203711100110000073216221787100020382038203820382038
100420371606116872510001000100026468002018203720371572318951000100020002037203711100110000073216221787100020382038203820382038
100420371506116872510001000100026468002018203720371572318951000100020002037203711100110000073216221787100020382038203820382038
100420371507916872510001000100026468002018203720371572318951000100020002037203711100110000073216221787100020382038203820382038
100420371506116872510001000100026468002018203720371572318951000100020002037203711100110000073216221787100020382038203820382038
100420371506116872510001000100026468002018203720371572318951000100020002037203711100110000073216221787100020382038203820382038
100420371506116872510001000100026468002018203720371572318951000100020002037203711100110000073216221787100020382038203820382038

Test 2: Latency 1->2

Code:

  shsub v0.4h, v0.4h, v1.4h
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)03191e3f4e51inst issue (52)~issue int (53)~issue fp/simd (54)~dispatch int (56)~dispatch fp/simd (57)huge thing int (59)huge thing fp/simd (5b)60696d6edispatch stall (70)scheduler rewind (75)scheduler stall (76)~dispatch op (78)~map op int (7c)~map op fp/simd (7e)~map lookup int (7f)~map lookup fp/simd (81)8283pipeline redirect (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst b.cc (94)inst integer (97)inst neon or fp (9a)9fa0a7a8a9acc2c5cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
1020420037150006119687251010010010000100100005002847680120018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
1020420037150006119687251010010010000100100005002847680120018200372003718422318745101002001000020020000200372003711102011009910010010000100001000071011611197910100001002003820038200382003820038
1020420037150006119687251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
1020420037150006119687431010010010000108100005002848963020018200372003718422318745101002001000020020328200372003711102011009910010010000100400702071011611197910100001002003820038200382003820038
1020420037150006119687251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
1020420037150006119687251010010010000100100005002847680120018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
1020420037150006119687251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
1020420037150006119687251010010010000100100005002847680120126200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
1020420037150006119687251010010010000100100005002847680120018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
1020420037150006119687251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)0308090b1e3f4e51inst issue (52)~issue int (53)~issue fp/simd (54)~dispatch int (56)~dispatch fp/simd (57)huge thing int (59)huge thing fp/simd (5b)60696b6d6edispatch stall (70)scheduler rewind (75)scheduler stall (76)~dispatch op (78)~map op int (7c)~map op fp/simd (7e)~map lookup int (7f)~map lookup fp/simd (81)8283pipeline redirect (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst b.cc (94)inst integer (97)inst neon or fp (9a)9faccfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10024200371500000611968725100101010000101000050284768012001802003720037184443187671001020100002020000200372003711100211091010100001006405162219785010000102003820038200382003820038
10024200371500000611968725100101010000101000050284768002001802003720037184443187671001020100002020000200372003711100211091010100001006403162219785010000102003820038200382003820038
10024200371500000611968725100101010000101000050284768002001802003720037184443187671001020100002020000200372003711100211091010100001006402162219785010000102003820038200382003820038
10024200371500000611968725100101010000101000050284768002001802003720037184443187671001020100002020000200372003711100211091010100001006403162219785010000102003820038200852003820038
10024200371500009611968725100101010000101000050284768002001802013320037184483187671001020100002020000200372003711100211091010100001006403162219785010000102003820038200382003820038
10024200371500000611968725100101010000101000050284768002001802003720037184443187671001020100002020000200372003711100211091010100001006402162219785010000102003820038200382003820038
10024200371500000611968725100231010000101000050284768002001802003720037184443187671001020100002020000200372003711100211091010100001006402162219785010000102003820038200382003820038
10024200371500000611968725100101010000101000050284768002001802003720037184443187671001020100002020000200372003711100211091010100001006403162219785010000102003820038200382003820038
100242003715000001031968725100101010000101000050284768002001802003720037184443187671001020100002020000200372003711100211091010100001006402162219785010000102003820038200382003820038
10024200371500000611968725100101010000101000050284768002001832003720037184443187671001020100002020000200372003711100211091010100001006403162219785210000102003820038200382003820038

Test 3: Latency 1->3

Code:

  shsub v0.4h, v1.4h, v0.4h
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)03080b18191e1f3a3f4e51inst issue (52)~issue int (53)~issue fp/simd (54)~dispatch int (56)~dispatch fp/simd (57)huge thing int (59)huge thing fp/simd (5b)60696d6edispatch stall (70)scheduler rewind (75)scheduler stall (76)~dispatch op (78)~map op int (7c)~map op fp/simd (7e)~map lookup int (7f)~map lookup fp/simd (81)8283pipeline redirect (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst b.cc (94)inst integer (97)inst neon or fp (9a)9fa0a1a6a8a9acc2cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
102042003715000000006119687251010010010000100100005002847680120018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
102042003715000000006119687251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
102042003715000000006119687251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
102042003715000000006119687251010010010000100100005002847680120018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
1020420037150000000061196872510100100100001001000050028476801200182003720037184223187451010020010000200200002003720037111020110099100100100001000000000710116111979121100001002003820038200382003820038
102042003715000000006119687251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
102042003715000000006119667251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
1020420037150000000012419687251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
102042003715000000008419687251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038
102042003715000000006119687251010010010000100100005002847680120018200372003718422318745101002001000020020000200372003711102011009910010010000100000000071011611197910100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)03080b18191e1f3a3f4e51inst issue (52)~issue int (53)~issue fp/simd (54)~dispatch int (56)~dispatch fp/simd (57)huge thing int (59)huge thing fp/simd (5b)60696d6edispatch stall (70)scheduler rewind (75)scheduler stall (76)~dispatch op (78)~map op int (7c)~map op fp/simd (7e)~map lookup int (7f)~map lookup fp/simd (81)8283pipeline redirect (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst b.cc (94)inst integer (97)inst neon or fp (9a)9fa1a8a9acc2c5cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
100242003715000000006119687251001010100001010000502847680120018200372003718444318767100102010000202000020037200371110021109101010000100000006402162219785210000102003820038200382003820038
1002420037150000000042019687251001010100001010000502847680020018200372003718444318767100102010000202000020037200371110021109101010000100000006402162219785010000102003820038200382003820038
100242003715000000006119687251001010100001010000502847680120018200372003718444318767100102010000202000020037200371110021109101010000100000006402162219785010000102003820038200382003820038
100242003715000000006119687251001010100001010000502847680120018200372003718444318767100102010000202000020037200371110021109101010000100100006402162219785010000102003820038200382003820038
1002420037150000012006119687251001010100001010000502847680120018200372003718444718767100102010000202000020085200374110021109101010000100000006712162219785010000102003820038200382008620038
100242008415000000006119687251001010100001010000502847680020018200372003718444318767100102010000202000020037200371110021109101010000100103006402162219785010000102003820038200382003820038
100242003715000000006119687251001010100001010000502847680120018200372003718444318767100102010000202000020037200371110021109101010000100003006402162219785010000102003820038200382003820038
100242003715000000006119687251001010100001010000502847680120018200372003718444318767100102010000202000020037200371110021109101010000100000006402162219785010000102003820038200382003820038
100242003715000000006119687251001010100361010000502851529120018200372003718444318767100102010000202000020037200371110021109101010000100003006402162219785010000102003820038200382003820038
1002420037150000000034519687251001010100001010000502847680120018200372003718444318767100102010000202000020037200371110021109101010000100000006402162219785010000102003820038200382003820038

Test 4: throughput

Count: 8

Code:

  shsub v0.4h, v8.4h, v9.4h
  shsub v1.4h, v8.4h, v9.4h
  shsub v2.4h, v8.4h, v9.4h
  shsub v3.4h, v8.4h, v9.4h
  shsub v4.4h, v8.4h, v9.4h
  shsub v5.4h, v8.4h, v9.4h
  shsub v6.4h, v8.4h, v9.4h
  shsub v7.4h, v8.4h, v9.4h
  movi v8.16b, 9
  movi v9.16b, 10

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.2505

retire (01)cycle (02)030b181e1f3f51inst issue (52)~issue int (53)~issue fp/simd (54)~dispatch int (56)~dispatch fp/simd (57)huge thing int (59)huge thing fp/simd (5b)60696d6edispatch stall (70)scheduler rewind (75)scheduler stall (76)~dispatch op (78)~map op int (7c)~map op fp/simd (7e)~map lookup int (7f)~map lookup fp/simd (81)8283pipeline redirect (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst b.cc (94)inst integer (97)inst neon or fp (9a)9fa8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
802042006015000004025801001008000010080000500640000020019200382003899733999680100200800002001600002003820038118020110099100100800001000051103161220035800001002003920039200392003920039
802042003815000004025801001008000010080000500640000020019200382003899733999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
8020420038150001804025801001008000010080000500640000120019200382003899733999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
8020420038150000061518010210980093100800965006400000200192003820038997331002380102200800002001600002003820038118020110099100100800001000051101251120035800001002003920039200392003920039
802042003815000132884025801001008000010080000500640000020019200382003899733999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
802042003815000004025801001008000010080000500640000020019200382003899733999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
802042003815000004025801001008000010080000500640000020019200382003899733999680100200800002001600002003820094218020110099100100800001000051101161120035800001002003920039200392003920039
802042003815000004025801001008000010080000500640000020019200382003899733999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
802042003815000004025801001008000010080000500640000020019200382003899733999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
802042003814900008225801001008000010080000500640000020019200382003899733999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.2505

retire (01)cycle (02)03181e3f51inst issue (52)~issue int (53)~issue fp/simd (54)~dispatch int (56)~dispatch fp/simd (57)huge thing int (59)huge thing fp/simd (5b)5f60696d6edispatch stall (70)scheduler rewind (75)scheduler stall (76)~dispatch op (78)~map op int (7c)~map op fp/simd (7e)~map lookup int (7f)~map lookup fp/simd (81)8283pipeline redirect (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst b.cc (94)inst integer (97)inst neon or fp (9a)9fa8cfd5d6ddinst fetch restart (de)e0eb? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
8002420047150003925800101080000108000050640000002001920038200389996310018800102080000201600002003820038118002110910108000010050203163220035080000102003920039200392003920039
8002420038150003925800101080000108000050640000002001920038200389996310018800102080000201600002003820038118002110910108000010050203162320035080000102003920039200392003920039
8002420038150003925800101080000108000050640000012001920038200389996310018800102080000201600002003820038118002110910108000010050203163220035080000102003920039200392003920039
800242003815002403925800101080000108000050640000002001920038200389996310018800102080000201600002003820038118002110910108000010050202162320035080000102003920039200392003920039
8002420038150003925800101080000108000050640000012001920038200389996310018800102080000201600002003820038118002110910108000010050202162320035080000102003920039200392003920039
8002420038150008125800101080000108000050640000002001920038200389996310018800102080000201600002003820038118002110910108000010050202163320035080000102003920039200392003920039
8002420038150008125800101080000108000050640000002001920038200389996310018800102080000201600002003820038118002110910108000010050203163220035080000102003920039200392003920039
8002420038150003925800101080000108000050640000002001920038200389996310018800102080195201600002003820038118002110910108000010050203163320035080000102003920039200392003920039
8002420038150003925800101080000108000050640000002001920038200389996310018800102080000201600002003820038118002110910108000010050202163220035080000102003920039200392003920039
80024200381500012325800101080000108000050640000002001920038200389996310018800102080000201600002003820038118002110910108000010050203163220035080000102003920039200392003920039