Apple M1 Microarchitecture Research by Dougall Johnson

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

SSUBW (vector, 8H)

Test 1: uops

Code:

  ssubw v0.8h, v0.8h, v1.8b
  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)a8acc2cfd5d6ddinst fetch restart (de)e0? fp/simd (ee)f5f6f7f8fd
1004203715061168725100010001000264680020182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203715061168725100010001000264680020182037203715723189510001000200020372037111001100080073116111787100020382038203820382038
10042037150103168725100010001000264680020182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203715061168725100010001000264680020182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203715061168725100010001000264680020182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203715061168725100010001000264680020182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203715061168725100010001000264680020182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203715061168725100010001000264680020182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203716061168725100010001000264680020182037203715723189510001000200020372037111001100000073116111787100020382038203820382038
1004203715061168725100010001000264680020182037203715723189510001000200020372037111001100000073116111787100020382038203820382038

Test 2: Latency 1->2

Code:

  ssubw v0.8h, v0.8h, v1.8b
  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)9fa0a1a6a7a8a9acc2c5cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10204200371500000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000000000071011611197910100001002003820038200382003820038
10204200371500000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000001000071011611197910100001002003820038200382003820038
10204200371500000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000000039380071011611197910100001002003820038200382003820038
10204200371500000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000000030071011611197910100001002003820038200382003820038
10204200371500000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000000030071011611197910100001002003820038200382003820038
10204200371500000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000000030071011611197910100001002003820038200382003820038
10204200371500000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000000000071011611197910100001002003820038200382003820038
102042003715000000003866196872510100100100001001000050028476800200182003720037184223187451010020010000200200002003720037111020110099100100100001000020101230071011611197910100001002003820038200382003820038
10204200371490000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000000000071011611197910100001002003820038200382003820038
10204200371500000000611968725101001001000010010000500284768002001820037200371842231874510100200100002002000020037200371110201100991001001000010000001030071011611197910100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)031e3f4e51inst 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)9fa6a8a9accdcfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
1002420037150061196872510010101000010100005028476800200182003720037184443187671001020100002020000200372003711100211091010100001002090640216221978510000102003820038200382003820038
1002420037150061196872510010101000010100005028476800200182003720037184523187671001020100002020000200372003711100211091010100001001260060640216221978510000102003820038200382003820038
1002420037150061196872510010101000010100005028476800200182003720037184443187671001020100002020000200372003711100211091010100001003000640216221978510000102003820038200382003820038
10024200371490611968725100101010000101000050284768002001820037200371844431876710010201000020200002003720037111002110910101000010000210640216221978510000102003820038200382003820038
10024200371500611968725100101010000101000071284768002001820037200371844431876710010201000020200002003720037111002110910101000010000150640216221978510000102003820038200382003820038
100242003715001241968725100101010000101000050284768002001820037200371844431876710010201000020200002003720037111002110910101000010000150640216221978510000102003820038200382003820038
10024200371500611968725100101010000101000050284768002001820037200371844431876710010201000020200002003720037111002110910101000010000180640216221978510000102003820038200382003820038
10024200371500611968725100101010000101000050284768012001820037200371844431876710010201000020200002003720037111002110910101000010000210640216221978510000102003820038200382003820038
10024200371500611968725100101010000101000050284768002001820037200371844431876710010201000020200002003720037111002110910101000010000150640216221978510000102003820038200382003820038
1002420037150061196872510010101000010100005028476800200182003720037184443187671001020100002020000200372003711100211091010100001000030640216221978510000102003820038200382003820038

Test 3: Latency 1->3

Code:

  ssubw v0.8h, v1.8h, v0.8b
  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)0318191e1f3f4e51inst 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)9fa1a6a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
1020420037150000018719687251010010010000100100005002847680120018020037200371842231874510100200100002002000020037200371110201100991001001000010000007101161119791100001002003820038200382003820038
1020420037150000010319687251010010010000100100005002847680020018020037200371842231874510100200100002002000020037200371110201100991001001000010000007101161119791100001002003820038200382003820038
102042003715000006119687251010010010000100100005002847680120018020037200371842231874510100200100002002000020037200371110201100991001001000010000007101161119791100001002003820038200382003820038
102042003715000306119687251010010010000100100005002847680120018020037200371842231874510100200100002002000020037200371110201100991001001000010000107101161119791100001002003820038200382003820038
1020420037150001206119687251010010010000124100006592847680020018020085200841842271874510100200100002002000020037200371110201100991001001000010000007101161119791100001002003820038200382003820038
1020420037150000012619687251010010010000100100005002847680120054020037200371842231874510100200101652022000020037200371110201100991001001000010000207101161119791100001002003820038200382003820038
102042003715000006119687251010010010000100100005002847680120018020037200371842231874510100200100002002000020037200371110201100991001001000010000007101161119791100001002003820038200382003820038
1020420037150000010319687251010010010000100100005002847680120018020037200371842231874510100200100002002000020037200371110201100991001001000010000007101161119791100001002003820038200382003820038
102042003715000006119687251010010010000100100005002847680120018020037200371842231874510100200100002002000020037200371110201100991001001000010000007101161119791100001002003820038200382003820038
102042003715000006119687251010010010000100100005002847680120018020037200371842231874510100200100002002000020037200371110201100991001001000010000007101161119791100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)03181e3f4e51inst 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)696d6edispatch 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)9fa8acc5cfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10024200371500066196872510010101000010100005028476802001820037200371844431876710010201000020200002003720037111002110910101000010000640216221978510000102003820038200382003820038
10024200371500061196872510010101000010100005028476802001820037200371844431876710010201000020200002003720037111002110910101000010000640216221978510000102003820038200382003820038
100242003715000366196872510010101000010100005028476802001820037200371844431876710010201000020200002003720037111002110910101000010000640216231978510000102003820038200382003820038
10024200371500061196872510010101000010100005028476802001820037200371844431876710010201000020200002003720037111002110910101000010000640216231978510000102003820038200382003820086
10024200371500061196872510010101000010100005028476802001820037200371844431876710010201000020200002003720037111002110910101000010000640216221978510000102003820038200382003820038
10024200371500061196872510010101000010100005028476802001820037200371844431876710010201000020200002003720037111002110910101000010000640216221978510000102003820038200382003820038
10024200371500061196872510010101000010100005028476802001820037200371844431876710010201000020200002003720037111002110910101000010030640216231978510000102003820038200382003820038
10024200371500061196872510010101000010100005028476802001820037200371844431876710010201000020200002003720037111002110910101000010000640216231978510000102003820038200382003820038
100242003715000170196872510010101000010100005028476802001820037200371844431876710010201000020200002003720037111002110910101000010000640216231978510000102003820038200382003820038
10024200371500061196872510010101000010100005028476802001820037200371844431876710010201000020200002003720037111002110910101000010000640216231978510000102003820038200382003820038

Test 4: throughput

Count: 8

Code:

  ssubw v0.8h, v8.8h, v9.8b
  ssubw v1.8h, v8.8h, v9.8b
  ssubw v2.8h, v8.8h, v9.8b
  ssubw v3.8h, v8.8h, v9.8b
  ssubw v4.8h, v8.8h, v9.8b
  ssubw v5.8h, v8.8h, v9.8b
  ssubw v6.8h, v8.8h, v9.8b
  ssubw v7.8h, v8.8h, v9.8b
  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)031e3f51inst 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)72scheduler 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
80204200381500198258010010080000100800005006400001200192003820038997303999680100200800002001600002003820038118020110099100100800001000051103161120035800001002003920039200392003920039
8020420038150040258010010080000100800005006400000200192003820038997303999680100200800002001600002003820038118020110099100100800001001051101161120035800001002003920039200392003920039
8020420038150040258010012080000100800005006400000200192003820038997303999680100200800002001600002003820038118020110099100100800001002351101161120035800001002003920039200392003920039
8020420038150040258010010080000100800005006400001200192003820038997303999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
8020420038150040258010010080000100800005006400000200192003820038997303999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
8020420038150040258010010080000100800005006400000200192003820038997303999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
8020420038150040258010010080000100800005006400000200192003820038997303999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
80204200381500822580100100800001008000050064000012001920038200389973031002280100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
8020420038150040258010010080000100800005006400001200192003820038997303999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039
8020420038150040258010010080000100800005006400001200192003820038997303999680100200800002001600002003820038118020110099100100800001000051101161120035800001002003920039200392003920039

1000 unrolls and 10 iterations

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

retire (01)cycle (02)0308181e3f51inst 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)9fa0a8cfd5d6daddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
80024200481500006225800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000100050203167322003580000102003920039200392003920039
80024200381500003925800101080000108000050640000120019200382003899963100188001020800002016000020038200381180021109101080000100050202165322003580000102003920039200392003920039
80024200381500003925800101080000108000050640000120019200382003899963100188001020800002016000020038200381180021109101080000100050203165322003580000102003920039200392003920039
80024200381500003925800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000100050202165332003580000102003920039200392003920039
80024200381500003925800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000100050203176332003580000102003920039200392003920039
80024200381500003925800101080000108000050640000120019200382003899963100188001020800002016000020038200381180021109101080000100050203166322003580000102003920039200392003920039
80024200381500103925800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000100050203166332003580000102003920039200392003920039
80024200381500003925800101080000108000050640000020019200382003899963100478001020800002016000020038200381180021109101080000100450203165322003580000102003920039200392003920039
80024200381500003925800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000100050203166332003580000102003920039200392003920039
80024200381500003925800101080000108000050640000020019200382003899963100188001020800002016000020038200381180021109101080000100050203165322003580000102003920039200392003920039