Apple Microarchitecture Research by Dougall Johnson

M1/A14 P-core (Firestorm): Overview | Base Instructions | SIMD and FP Instructions
M1/A14 E-core (Icestorm):  Overview | Base Instructions | SIMD and FP Instructions

FCVTZS (scalar, fixed-point, S to S)

Test 1: uops

Code:

  fcvtzs s0, s0, #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 uop (01)cycle (02)031e3f4e51schedule uop (52)schedule simd uop (54)dispatch simd uop (57)ldst uops in schedulers (5b)60696d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map simd uop (7e)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst simd alu (9a)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)f5f6f7f8fd
100430372308825472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372396125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372406125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110001073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
10043037231210325472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723010325472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372406125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtzs s0, s0, #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 uop (01)cycle (02)031e3f4e51schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)60696d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)inst simd alu (9a)inst ldst (9b)9fl1d cache writeback (a8)acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
102043003723301702954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000001000007102161129633100001003003830038300383003830038
102043003723301892954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000001000007101161129633100001003003830038300383003830038
102043003723302112954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000001000007101161129633100001003003830038300383003830038
10204300372320842954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000001000007101161129633100001003003830038300383003830038
10204300372330842954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000001000007101161129633100001003003830038300383003830038
102043003723305432954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000001001007101161129633100001003003830038300383003830038
10204300372330612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000001000007101161129633100001003003830038300383003830038
102043003723201702954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000001000007101161129633100001003003830038300383003830038
102043003723302002954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000001000007101161129633100001003003830038300383003830038
102043003723305402954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000001000007101161129633100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)031e1f3f4e51schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)60696d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)inst simd alu (9a)9fl1d cache writeback (a8)a9acc2branch cond mispred nonspec (c5)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
100243003723300612954725100101010000101000050427716013001830037300372828632876710010201000020100003003730037111002110910101000010490000640616222962910000103003830038300383003830038
1002430037232007262954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010520000640216222962910000103003830038300383003830038
1002430037233006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000105301200640216222962910000103003830038300383003830085
100243003723300612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010440000640216222962910000103003830038300383003830038
100243003723315061295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038
10024300372320061295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001030000640216222962910000103003830038300383003830038
1002430037233001452954725100101010000101000050427716013001830037300372828632876710010201000020100003003730037111002110910101000010490600640216222962910000103003830038300383003830038
100243003723300612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010490283800640216222962910000103003830038300383003830038
100243003723200612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010450000640216222962910000103003830038300383003830038
1002430037232006129547251001010100001010000504277160030018300373003728286328767100102010000201000030037300371110021109101010000100013500640216222962910000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtzs s0, s8, #3
  fcvtzs s1, s8, #3
  fcvtzs s2, s8, #3
  fcvtzs s3, s8, #3
  fcvtzs s4, s8, #3
  fcvtzs s5, s8, #3
  fcvtzs s6, s8, #3
  fcvtzs s7, s8, #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 uop (01)cycle (02)03191e3a3f51schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)60696d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)inst simd alu (9a)9fl1d tlb access (a0)l1d cache writeback (a8)acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)e0ea? simd retires (ee)? int retires (ef)f5f6f7f8fd
80204200691550003025801081008000810080020500640132020020200392003999776999080120200800322008033920039200391180201100991001008000010000001115118116200360800001002004020040200402004020040
80204200391550003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016200360800001002004020040200402004020040
802042003915501203025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016200360800001002004020040200402004020040
80204200391550003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016200360800001002004020040200402004020040
802042003915500027725801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016200360800001002004020040200402004020040
80204200391660003025801081008000810080020500640132020020200392003999776999080120200800322008045720092200391180201100991001008000010000001115118016200360800001002004020040200402004020040
80204200391550003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016200360800001002004020040200402004020040
80204200391550003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010020001115118016200360800001002004020040200402004020040
80204200391560003525801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016200360800001002004020040200402004020040
80204200391560005825801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000301115118016200360800001002004020040200402004020040

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03l1i tlb fill (04)mmu table walk data (08)09181e1f3f51schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)60696b6d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)inst simd alu (9a)9fl1d cache writeback (a8)accfd2l1i cache miss demand (d3)l1i tlb miss demand (d4)d5map dispatch bubble (d6)ddfetch restart (de)e0eb? simd retires (ee)? int retires (ef)f5f6f7f8fd
80024200501551010004025800101080000108000050640000020020020039200399996310019800102080000208000020039200391180021109101080000100650210012346221920036080000102004020040200402004020040
800242003915510100011625800101080000108000050640000020020020039200399996310019800102080000208000020039200391180021109101080000101350210012230221320036080000102004020040200402004020040
80024200391551010008925800101080000108000050640000020020020039200399996310019800102080000208000020039200391180021109101080000100050210011830221120036080000102004020040200402004020040
8002420090155111001768847800101080000108000050640000020020020142200399996310019800102080000208000020039200391180021109101080000100050210012231232320036080000102004020040200402004020040
80024200391551010008825800101080000108000050640000020020020039200399996310019800102080000208000020039200394180021109101080000101050210012231142220036080000102004020040200402004020040
80024200391551010008825800101080000108000050640000020020020039200399996310019800102080000208000020039200391180021109101080000100050210012346232220036080000102004020040200402004020040
800242003915610100079525800101080000108000050640000020020020039200399996310019800102080000208000020039200391180021109101080000100050210012130221520036080000102004020040200402004020040
800242003915510100013025800101080000108000050640000020020020039200399996310019800102080000208000020039200391180021109101080000100050210012330172220036080000102004020040200402004020040
800242003915610130088258001010800001080000506400000200200200392003910006310019800102080000208000020039200391180021109101080000101050210011830212320036080000102004020040200402004020040
80024200981551010008825800101080000108000050640000020020020039200399996310019800102080000208000020039200391180021109101080000100050210012231192220036080000102004020040200402004020040