Apple M1 Microarchitecture Research by Dougall Johnson

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

USHR (vector, 4S)

Test 1: uops

Code:

  ushr v0.4s, v0.4s, #3
  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)031e3a3f4e51inst 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
1004203716009716862510001000100026452102018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
1004203716006116862510001000100026452112018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037151206116862510001000100026452102018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037160010316862510001000100026452112018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
1004203715006116862510001000100026452112018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
1004203716006116862510001000100026452112018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150012416862510001000100026452112018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037163012616862510001000100026452102018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150058116862510001000100026452112018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037160023516862510001000100026452112018203720371571318951000100010002037203711100110000073116111786100020382038203820382038

Test 2: Latency 1->2

Code:

  ushr v0.4s, v0.4s, #3
  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)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)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)9fa6a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
102042003715500103196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000007101161119791100001002003820038200382003820038
10204200371550061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000007101161119791100001002003820038200382003820038
10204200371610061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000007101161119791100001002003820038200382003820038
10204200371550061196862510100100100001001000050028475210200182003720037184213187451010020010000200100002003720037111020110099100100100001000007101161119791100001002003820038200382003820038
10204200371550061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000007101161119791100001002003820038200382003820038
10204200371550061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000007101161119791100001002003820038200382003820038
10204200371550061196862510100100100001001000050028475210200182003720084184213187451010020010000200100002003720037111020110099100100100001000007101161119791100001002003820038200382003820038
10204200371560061196862510100100100001001000050028475210200182003720037184213187451010020010000200100002003720037111020110099100100100001000007101161119791100001002003820038200382003820038
10204200371550061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000007101161119791100001002003820038200382003820038
10204200371550061196862510100100100001001000050028475210200182003720037184213187451010020010000200100002003720037111020110099100100100001000007101161119791100001002003820038200382003820038

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)9faccfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
100242003716106119686251001010100001010000502847521020018200372003718443318767100102010000201000020037200371110021109101010000100640216221978610000102003820038200382003820038
100242003715506119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100640216221978610000102003820038200382003820038
100242003715506119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100640216221978610000102003820038200382003820038
100242003715506119686251001010100001010000502847521020018200372003718457318767100102010000201000020037200371110021109101010000100640216221978610000102003820038200382003820038
100242003715506119686251001010100001010000502847521120018200372003718443318767100102010000201016820037200371110021109101010000100640216221978610000102003820038200382003820038
100242003715506119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100640216221978610000102003820038200382003820038
1002420037155031719686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100640416221978610000102003820038200382003820038
100242003715506119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100669216221978610000102003820038200382003820038
100242003715506119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100640216221978610000102003820038200382003820038
10024200371550611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010585640216221978610000102003820038200382003820038

Test 3: throughput

Count: 8

Code:

  ushr v0.4s, v8.4s, #3
  ushr v1.4s, v8.4s, #3
  ushr v2.4s, v8.4s, #3
  ushr v3.4s, v8.4s, #3
  ushr v4.4s, v8.4s, #3
  ushr v5.4s, v8.4s, #3
  ushr v6.4s, v8.4s, #3
  ushr v7.4s, v8.4s, #3
  movi v8.16b, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

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

retire (01)cycle (02)0308191e3f51inst 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)9fa8a9acc5branch mispredict (cb)cdcfd5d6e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
8020420059160000219258010810080008100800205006401321200192003820038997769986801202008003220080032200382003811802011009910010080000100000111511801620035800001002003920039200392003920039
802042003815500029258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100003111511801620035800001002003920039200392003920039
802042003815500071258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100000111511801620035800001002003920039200392003920039
802042003815500029438020410080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100000111511801620035800001002003920039200392003920039
802042003815500029258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100043111511801620035800001002003920039200392003920039
802042003815500029258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100000111511801620035800001002003920039200392003920039
802042003815500029258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100000111511801620035800001002003920039200392003920039
802042003815500029258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100003111513601620035800001002003920039200392003920039
802042003815500029258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100000111511801620035800001002003920039200392003920039
802042003815500029258010810080008100800205006401320200192003820038997769989801202008003220080032200382003811802011009910010080000100000111511811620035800001002003920039200392003920039

1000 unrolls and 10 iterations

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

retire (01)cycle (02)030818191e1f3f51inst 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)6061696d6edispatch 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)9fa0a1a8a9acc2cfd0d2d5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
80024200391550000039258001010800001080000506400000020019200382003899963100188001020800002080099200382003811800211091010800001000300050200013161292003580000102003920039200392003920039
8002420038156000390392580010108000010800005064000000200192003820038999631001880010208000020802932010120038118002110910108000010000000502000141614162003580000102003920039200392003920039
800242003815500000392580010108000010800005064000000200192003820038999631001880010208000020800002003820038118002110910108000010000000502000101615122003580000102003920039200392003920039
800242024615500090392580010108000010800005064000010200192003820038999631001880010208000020800002003820038118002110910108000010000000502000151618142003580000102003920039200392003920039
800242003815500000392580010108000010800005064000000200192003820038999631001880010208000020800002003820038118002110910108000010000000502000151610142003580000102003920039200392003920039
8002420038155010003925800101080000108000050640000002001920038200389996310018800102080000208000020038200381180021109101080000100000180502054141613102003580000102003920039200392003920039
800242003816100000392580010108000010800005064000010200192003820038999631001880010208000020800002003820038118002110910108000010000000502000151614142003580000102003920039200392003920039
800242003815500000392580010108000010800005064000005200192003820038999631001880010208000020800002003820038118002110910108000010000000502054121616132003580000102003920089200392003920039
80024200381550000352392580010108000010800005064000010200192003820038999631001880010208000020800002003820038118002110910108000010000000502054151615132003580000102003920039200392003920039
800242003815500000392580010108000010800005064000000200192003820038999631001880010208000020800002003820038118002110910108000010000000502000111613162003580000102003920039200392003920039