Apple M1 Microarchitecture Research by Dougall Johnson

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

URSHR (vector, 16B)

Test 1: uops

Code:

  urshr v0.16b, v0.16b, #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)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
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372206125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723015625472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303722156125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723486125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372366125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372266125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038

Test 2: Latency 1->2

Code:

  urshr v0.16b, v0.16b, #3
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 3.0037

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)9fa0a1a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10204300372250612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000007101161129633100001003003830038300383003830038
1020430037225636612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000007101161129633100001003003830038300383003830038
10204300372250612954725101001001000010010000500427716013001830037300372826432874510100200100002001000030037300371110201100991001001000010000007101161129633100001003003830038300383003830038
10204300372250612954725101001001000010010000500427716013001830037300372826432874510100200100002001000030037300371110201100991001001000010020007101161229633100001003003830038300383003830038
10204300372250612954725101001001000010010000500427716013001830037300372826432874510100200100002001000030037300371110201100991001001000010000007101161129633100001003003830038300383003830038
10204300372250612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000007101161129633100001003003830038300383003830038
10204300372250612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000007101161129633100001003003830038300383003830038
10204300372250612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000007101161129633100001003003830038300383003830038
10204300372250612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010020007101161129633100001003003830038300383003830038
10204300372250612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000007101161129633100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire (01)cycle (02)0307080a0b18191e1f3a3f4e51inst 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)9fa0a1a6a7a8a9acc2cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
100243003722510100000267295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000000000644101651029629010000103003830038300383003830038
1002430037225101000002672954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000000006441016111029629010000103003830038300383003830038
100243003722410100000267295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000000000644616101029629010000103003830038300383003830038
100243003722510100001322672954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000000006441016101029629010000103003830038300383003830038
10024300372251010000026729547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000001506441016101029629010000103003830038300383003830038
10024300372251010000026540295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000000000644111681029629010000103003830038300383003830038
1002430037225101000002672954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000000006441016101029629010000103003830038300383003830038
100243003722510100030267295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000000000644111611629629010000103003830038300383003830038
100243003722510100100267295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000000000644816101029629010000103003830038300383003830038
1002430037225101000002672954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000000006441117101129629010000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  urshr v0.16b, v8.16b, #3
  urshr v1.16b, v8.16b, #3
  urshr v2.16b, v8.16b, #3
  urshr v3.16b, v8.16b, #3
  urshr v4.16b, v8.16b, #3
  urshr v5.16b, v8.16b, #3
  urshr v6.16b, v8.16b, #3
  urshr v7.16b, v8.16b, #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)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)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)9fa0a1a8c5branch mispredict (cb)cdcfd0d5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
80204200391500762580108100800081008002050064013200200202003920039997769990801202008003220080032200392003911802011009910010080000100000111511801360120036800001002004020040200402004020040
80204200391500302580108100800081008002050064013200200202003920039997769990801202008003220080032200392003911802011009910010080000100000111511800160020036800001002004020040200402004020040
80204200391500302580108100800081008002050064013200200202003920039997769990801202008003220080032200392003911802011009910010080000100000111511800160020036800001002004020040200402004020040
80204200391500512580108100800081008002050064013200200202003920039997769990801202008003220080032200392003911802011009910010080000100000111511800160020036800001002004020040200402004020040
80204200391500302580108100800081008002050064013200200202003920039997769990801202008003220080032200392003911802011009910010080000100000111511800160020036800001002004020040200402004020040
80204200391500302580108100800081008002050064013200200202003920039997769990801202008003220080032200392003911802011009910010080000100000111511800160020036800001002004020040200402004020040
802042003915001602580108100800081008002050064013200200202003920039997769990801202008003220080032200392003911802011009910010080000100000111511800160020036800001002004020040200402004020040
80204200391500302580108100800081008002050064013200200202003920039997769990801202008003220080032200392003911802011009910010080000100000111511800160120036800001002004020040200402004020040
802042003915009392580108100800081008002050064013200200202003920039997769990801202008003220080032200392003911802011009910010080000100000111511800160020036800001002004020040200402004020040
80204200391500302580108100800081008002050064013200200202003920039997769990801202008003220080032200392003911802011009910010080000100000111511800160120036800001002004020040200402004020040

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)9fa8accfd5d6ddinst fetch restart (de)e0? int output thing (e9)eaeb? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
800242005015000402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010005020116112003600080000102004020040200402004020040
800242003915000402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010005020116112003600080000102004020040200402004020040
8002420039155001242580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010005020116112003600080000102004020040200402004020040
800242003915000402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010605020116112003600080000102004020040200402004020040
800242003915000402580010108000010800005564000000200202003920039999631001980010208000020800002003920039118002110910108000010005020116112003600080000102004020040200402004020040
800242003915000402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010005020116112003600080000102004020040200402004020040
800242003915000402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010005020116112003600080000102004020040200402004020040
800242003915000402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010005020116112003600080000102004020040200402004020040
8002420039150004025800101080000108000050640000002002020039200399996310019800102080000208000020039200391180021109101080000100050201161120036042080000102004020040200402004020040
800242003915000402580010108000010801075064000000200202003920039999631001980010208000020800002003920039118002110910108000010105020116112003600080000102004020040200402004020040