Apple M1 Microarchitecture Research by Dougall Johnson

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

USUBL2 (vector, 4S)

Test 1: uops

Code:

  usubl2 v0.4s, v0.8h, v1.8h
  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)a7a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)f5f6f7f8fd
1004203715061168725100010001000264680120182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203716061168725100010001000264680120182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203716061168725100010001000264680020182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203715061168725100010001000264680120182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203715061168725100010001000264680120182037203715723189510001000200020372037211001100000073116111787100020382038203820382038
1004203715061168725100010001000264680120182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203716061168725100010001000264680120182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203716061168725100010001000264680120182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203715061168725100010001000264680120182037203715723189510001000200020372037111001100020073116111787100020382038203820382038
1004203716061168725100010001000264680120182037203715723189510001000200020372037111001100000073116111787100020382038203820382038

Test 2: Latency 1->2

Code:

  usubl2 v0.4s, v0.8h, v1.8h
  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)030818191e1f3a3f4e51inst 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)9fa0a1a6a7a8a9acc2c5branch mispredict (cb)cdcfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
102042003715500000061196872510100100100001001000050028476800200182003720037184223187451010020010000200200002003720037111020110099100100100001000000000000071011611197910100001002003820038200862003820038
1020420037156000000103196872510100100100001001000050028476801200182003720037184223187451010020010000200200002003720037111020110099100100100001000000000000071011611197910100001002003820038200382003820038
102042003715500000061196872510100100100001001000050028476800200182003720037184223187451010020010000200200002003720037111020110099100100100001000000000000071011611197910100001002003820038200382003820038
102042003715500000061196872510100100100001001000050028476800200182003720037184223187451010020010000200200002003720037111020110099100100100001000000000000071011611197910100001002003820038200382003820038
102042003715500000061196872510100100100001001000050028476801200182003720037184223187451010020010000200200002003720037111020110099100100100001000000003000071011611197910100001002003820038200382003820038
102042003715500000061196872510100100100001241000050028476801200182003720037184296187411010020010008200200162003720037111020110099100100100001000000000011171801600198010100001002003820038200382003820038
102042003715500000061196872510100100100001001000050028476801200182003720037184223187451010020010000200200002003720037111020110099100100100001000000000000071011611197910100001002003820038200382003820038
102042003715500000061196872510100100100001001000050028476801200182003720037184223187451010020010000200200002003720037111020110099100100100001000000000000071011611197910100001002003820038200382003820038
102042003715500000061196872510100100100001001000050028476801200182003720037184223187451010020010000200200002003720037111020110099100100100001000000000000071011611197910100001002003820038200382003820038
102042003715500000061196872510100100100001001000050028476801200182003720037184223187451010020010000200200002003720037111020110099100100100001000000000000071011611197910100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)03091e3f4e51inst 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)9fa0a8acbranch mispredict (cb)cdcfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10024200371550061196872510010101000010100005028476801200182003720037184443187671001020100002020000200372003711100211091010100001000000640216221978510000102003820038200382003820038
10024200371550061196872510010101000010100005028476801200182003720037184443187671001020100002020000200372003711100211091010100001000000640216221978510000102003820038200382003820038
10024200371550061196872510010101000010100005028476801200182003720037184443187671001020100002020000200372003711100211091010100001000000640216221978510000102003820038200382003820038
10024200371560061196872510010101000010100005028476801200182003720037184443187671001020100002020000200372003711100211091010100001000000640216221978510000102003820038200382003820085
100242003715500232196872510010101000010100005028476801200182003720037184443187671001020100002020000200372003711100211091010100001000000640216221978510000102003820038200382003820038
10024200371560061196872510010101000010100005028476801200182003720037184443187671001020100002020000200372003711100211091010100001000000640216221984610000102003820038200382003820038
10024200371550061196872510010101000010100005028476801200182003720037184443187671001020100002020000200372003711100211091010100001000000640216221978510000102003820038200382003820038
10024200371550061196872510010101000010100005028476801200182003720037184443187671001020100002020000200372003711100211091010100001000000640216221978510000102003820038200382003820038
10024200371550061196872510010101000010100005028476801200182003720037184443187671001020100002020000200372003711100211091010100001000000640216221978510000102003820038200382003820038
10024200371550061196872510010101000010100005028476801200182003720037184443187671001020100002020000200372003711100211091010100001000000640216221978510000102003820038200382003820038

Test 3: Latency 1->3

Code:

  usubl2 v0.4s, v1.8h, v0.8h
  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)9fa1a6a8a9acc2cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10204200371550000000611968725101001001000010010000500284768012001820037200371842231874510100200100002002000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
10204200371550000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000003071011611197910100001002003820038200382003820038
10204200371550000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715500000001311968725101001001000010010000500284768012001820037200371842231874510100200100002002000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715500000006119687251010010010000100100005002847680020018200372003718422318745101002001000020020000200372003711102011009910010010000100000051071011611197910100001002003820038200382003820038
10204200371550000000611968725101001001000010010000500284768012001820037200371842231874510100200100002002000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
10204200371550000000611968725101001001000010010000500284768012001820037200371842231874510100200100002002000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715500000003461968725101001001000010010000500284768012001820037200371842231874510100200100002002000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715500000001031968725101001001000010010000500284768012001820037200371842231874510100200100002002000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
10204200371550000000821968725101001001000010010000500284768012001820037200371842231874510100200100002002000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)030b18191e1f3f4e51inst 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)9fa0a1a6a8a9accfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
1002420037155000006119687251001010100001010000502847680020018200372003718444318767100102010000202000020037200371110021109101010000100000006403162319785010000102003820038200382003820038
100242003715504454044033621964311510071121006016109127128540950201622022820275184573018860107722110817202190220275202627110021109101010000100022296887274652319984410000102027720275202732027620325
100242031915715567244033721961011410076131006012107606028540190202342027220276184602618853106252410819242194020276202756110021109101010000100001036402162219785010000102003820038200382003820038
100242003715500000136719687821004816100361410760602847680120018200372003718444318767100102010668222131420225200841110021109101010000100001458887452403219970310000102027620278202762027320273
100242027615700002641073196876210038101003615106086628528120201982022920277184593187671001020106642221332202872022651100211091010100001020002667883654219785310000102041720132201352003820132
1002420419163055660352248019610155101101010000101000088286051012027020226200371846230188971077222113172020000200372032451100211091010100001002000178557942162219785010000102003820038200382003820038
10024200371550000071196872510010101000010100005028476800200182003720037184443187671001020100002020000200372003711100211091010100001000070066402162219785010000102003820038200382003820038
10024200371550000061196872510010101000010100005028476800200182003720037184443187671001020100002020000200372003711100211091010100001000082036402162219785010000102003820038200382003820038
10024200371560000072619687251001010100001010000502847680020018200372003718444318767100102010000202000020037200371110021109101010000100000036402162219785010000102003820038200382003820038
1002420037155000006119687251001010100001010000502847680020018200372003718444318767100102010000202000020037200371110021109101010000100000036402162219785010000102003820038200382003820038

Test 4: throughput

Count: 8

Code:

  usubl2 v0.4s, v8.8h, v9.8h
  usubl2 v1.4s, v8.8h, v9.8h
  usubl2 v2.4s, v8.8h, v9.8h
  usubl2 v3.4s, v8.8h, v9.8h
  usubl2 v4.4s, v8.8h, v9.8h
  usubl2 v5.4s, v8.8h, v9.8h
  usubl2 v6.4s, v8.8h, v9.8h
  usubl2 v7.4s, v8.8h, v9.8h
  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)030b1e3f51inst 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)9fa8acbranch mispredict (cb)cdcfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
802042005815509402580100100800001008000050064000002001920038200389973399968010020080000200160000200382003811802011009910010080000100000051102161120035800001002003920039200392003920039
802042003815500822580100100800001008000050064000002001920038200389973399968010020080000200160000200382003811802011009910010080000100000051101161120035800001002003920039200392003920039
8020420038155012402580100100800001008000050064000012001920038200389973399968010020080000200160000200382003811802011009910010080000100000051101161220035800001002003920039200392003920039
802042003815500402580100100800001008000050064000002001920038200389973399968010020080000200160000200382003811802011009910010080000100000051101162120035800001002003920039200392003920039
8020420038156012402580100100800001008000050064000002001920038200389973399968010020080000200160000200382003811802011009910010080000100100051101161120035800001002003920039200392003920039
8020420038155007682580100100800001008000050064000002001920038200389973399968010020080000200160000200382003811802011009910010080000100000051101161120035800001002003920039200392003920039
802042003815500822580100100800001008000050064000002001920038200389973399968010020080000200160000200382003811802011009910010080000100100051101163120035800001002003920039200392003920039
802042003816000402580100100800001008000050064000002001920038200389973399968010020080000200160000200382003811802011009910010080000100000051101161120035800001002003920039200392003920039
802042003815500402580100100800001008000050064000002001920038200389973399968010020080000200160000200382003811802011009910010080000100000051101161120035800001002003920039200392003920039
8020420038155012402580100100800001008000050064000002001920038200389973399968010020080000200160000200382003811802011009910010080000100000051101161120035800001002003920039200392003920039

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)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)9fa8accficache miss (d3)d5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
80024200391560051425800101080000108000050640000020019200382003899963100188011820800002016000020038200381180021109101080000100050200216222003580000102003920039200392003920039
8002420038155003925800101080000108000050640000120019200382003899963100188001020800002016000020038200381180021109101080000100050200216222003580000102003920039200392003920039
8002420038155003925800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000100350200216222003580000102003920039200392003920039
8002420038155003925800101080000108000050640000120067200382003899963100188001020800002016000020038200381180021109101080000100050200316232003580000102003920039200392003920039
8002420038156003925800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000100350200216232003580000102003920039200392003920039
80024200381550339258001010800001080000506400000200192003820038999631001880010208000020160000200382003811800211091010800001013050200316232003580000102003920039200392003920039
8002420038155003925800101080000108000050640000120019200382003899963100188001020800002016000020038200381180021109101080000100050200216222003580000102003920039200392003920039
8002420038155006125800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000103050200216222003580000102003920039200392003920039
8002420038155003925800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000100350200216222003580000102003920039200392003920039
8002420038161003925800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000100050200216222003580000102003920039200392003920039