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

UCVTF (scalar, fixed-point, D from X)

Test 1: uops

Code:

  ucvtf d0, x0, #3
  mov x0, 1
  mov x1, 2

(no loop instructions)

1000 unrolls and 1 iteration

Retires: 2.000

Issues: 2.000

Integer unit issues: 0.000

Load/store unit issues: 1.000

SIMD/FP unit issues: 1.000

retire uop (01)cycle (02)031e3f4f51schedule uop (52)schedule simd uop (54)schedule ldst uop (55)dispatch simd uop (57)dispatch ldst uop (58)simd uops in schedulers (5a)ldst uops in schedulers (5b)60696d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map ldst uop (7d)map simd uop (7e)map ldst uop inputs (80)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst simd alu (9a)ld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? ldst retires (ed)? simd retires (ee)f5f6f7f8fd
2004376303610252000100010001000100014075228201357376376723109200010001000100010003763761110011000100000731161137310001000377377377377377
2004376303610252000100010001000100014075228201357376376723109200010001000100010003763761110011000100000731161137310001000378377377377378
2004376303610252000100010001000100014075228201357376380723109200010001000100010003763761110011000100000731161137310001000377377377377377
2004376303610252000100010001000100014075228201357376376723109200010001000100010003763761110011000100000731161137310001000380377377377377
2004376303610252000100010001000100014075228201357376376723109200010001000100010003763761110011000100000731161137310001000377377377382377
20043762123610252000100010001000100014075228201357376376723109200010001000100010003763761110011000100000731161137310001000377377377377377
2004376203611252000100010001000100014075228201357376376723109200010001000100010003763761110011000100000731161137310001000384387377377377
2004376303610252000100010001000100014075228201357376376723109200010001000100010003763761110011000100003731161137310001000377377377377377
2004376303610252000100010001000100014075228201357379376723109200010001000100010003763761110011000100000731161137310001000377377377377377
2004376203610252000100010001000100014075228201357376376723109200010001000100010003763761110011000100000731161137310001000377377377377377

Test 2: Latency 1->2 roundtrip

Code:

  ucvtf d0, x0, #3
  fmov x0, d0
  mov x0, 1
  mov x1, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 13.0032

retire uop (01)cycle (02)03mmu table walk data (08)l2 tlb miss data (0b)18191e1f3a3f464f51schedule uop (52)schedule int uop (53)schedule simd uop (54)schedule ldst uop (55)dispatch int uop (56)dispatch simd uop (57)dispatch ldst uop (58)int uops in schedulers (59)simd uops in schedulers (5a)ldst uops in schedulers (5b)60696b6d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map ldst uop (7d)map simd uop (7e)map int uop inputs (7f)map ldst uop inputs (80)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 tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
3020413003297400000001300170119408254010010100200001000010020000100005006214497148027091130065013003213003212546631262403010020010000200002001000020000130032130032112020210099100101001000010000100000000000131013162212951910000100001000010100130033130033130033130033130033
3020413003297400000001300170119408254010010100200001000010020000100005006214497148027091130013013003613003212546631262403010020010000200002001000020000130032130032112020110099100101001000010000100000000000131012162212951910000100001000010100130033130071130064130033130033
3020413003297400000001300170119408254010010100200001000010020000100005006214497148027091130147013003213003212546631262483010020010000200002001000020000130032130032112020110099100101001000010000100561416999000001949143183212951910092100001000010100133534132920133572132973133124
3020413359499601384156762552113339401208306584040810206201261007416224318120098426303837150383651132857013003213003212546624812857837116248123252524525612567253391330441336393812020110099100101001000010000100000030000131012162212951910000100001000010100130033130033130033130033130033
3020413003297400000021300170119408254010010100200001000010020000100005006214497148027091130013013003213003212546631262403010020010000200002001000020000130032130069112020110099100101001000010000100000000000131012162212951910000100001000010100130033130033130122130033130033
30204130032974000012001300171119408714012910103200031000010420117100005006214641148032851130013013003213003212546631262423010020010000200002021000020000130032130032112020110099100101001000010000100001000000190512162212951910000100001000010100130033130033133994130828130033
302041300351008000030013001701196611094022910148200271000611921863107845166236263148935581130711013003213134212603494126438322692081122320733200108592000013139413003517120201100991001010010000100221000602424011000149913682413029910041100001000010100130620131706130847131004130641
30204130922988000000013001701194082540100101002000010000100200001014750062144971480270901300130130034130032125466201262403010020010000200002021055220000131375130383112020110099100101001000010000100000000000131012162212951910000100001000010100130033130033130033130033130033
30204130032974000039001300180119408254010010100200001000010020000100005006214497148027090130013013003213003212546631262403010020010000200002001000020000130032130032112020110099100101001000010000100001000000131012162212952110000100001000010100130033130033130038130033130033
302041300329740000000130017011940825401001013020000100001002000010000500621449714802709113001301300321300331254663126240301002001000020000200100002000013003513003411202011009910010100100001000010000001140000132912262312952010000100001000010100130033130117130034130033130033

1000 unrolls and 10 iterations

Result (median cycles for code): 13.0032

retire uop (01)cycle (02)03mmu table walk data (08)l2 tlb miss instruction (0a)l2 tlb miss data (0b)18191e1f3f4f51schedule uop (52)schedule int uop (53)schedule simd uop (54)schedule ldst uop (55)dispatch int uop (56)dispatch simd uop (57)dispatch ldst uop (58)int uops in schedulers (59)simd uops in schedulers (5a)ldst uops in schedulers (5b)60696b6d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map ldst uop (7d)map simd uop (7e)map int uop inputs (7f)map ldst uop inputs (80)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)ld unit uop (a6)l1d cache writeback (a8)acbranch mispred nonspec (cb)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
30024130032100800000001300171194082540010100102000010000102000010000506214497148005281130013013003213003212548931262623001020100002000020100002000013003213006811200211091010010100001001000000012704162212951910003100001000010010130033130033130033130033130033
30024130032100800000001300171194082540010100122000010000102000010000506214497148005281130013013003213003212548931262623001020100002000020100002000013003213003211200211091010010100001001000000012702162312951910000100001000010010130033130033130033130033130033
3002413003210081000000130017119408254001010010200001000010200001000050621449714800528113001301300321300321254891011262623001020100002013020100002000013011613003211200211091010010100001001000000012702162212952510000100001000010010130033130033130033130033130033
30024130032100800000001300171194082540010100102000010002102000010000506214497148005281130019013003213003212548931262623001020100002000020100002000013003213003211200211091010010100001001000000012702162312951910000100001000010010130033130033130033130033130033
30024130034100800000901300171194082540010100102000010000102000010000506214497148005281130013013003213003212549231262623001020100002000020100002000013003213003211200211091010010100001001000000012702162212951910000100001000010010130033130033130033130033130033
30024130033100800000001300171194082540017100102000010000102000010000506214497147696351130013013003213003212548931262673001020100002000020100002000013003213003211200211091010010100001001000000012702162212952110000100001000010010130033130033130033130377130385
30024131848102711027293840220013256212050967740213100482009310062152337911519826278550149724791131914013272113264112666415812785934143261188323013221183923026132683132646271200211091010010100001021004411239850204354124813276810065100001000010010133745133370133784133652133318
30024133271103710100001300171194082540010100102000010000102000010000506214497148005281130013013003213003212548931262623001020100002000020100002000013003213003211200211091010010100001001000000012702162212952010000100001000010010130033130069130033130033130033
30024130032100800000001319981194082540010100102000010000102000010000506214497148005281130013013003213003212548931262623001020100002000020100002000013003213003211200211091010010100001001000000012702162412956110000100001000010010130033130033130033130033130033
30024130032100800000001300171194082540010100102000010000102000010000506214497148005281130013013003213003212548931262623001020100002000020100002000013003213003211200211091010010100001001000020012702162312951910000100001000010010130033130033130033130033130033

Test 3: throughput

Count: 8

Code:

  ucvtf d0, x8, #3
  ucvtf d1, x8, #3
  ucvtf d2, x8, #3
  ucvtf d3, x8, #3
  ucvtf d4, x8, #3
  ucvtf d5, x8, #3
  ucvtf d6, x8, #3
  ucvtf d7, x8, #3
  mov x8, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.3339

retire uop (01)cycle (02)03mmu table walk data (08)09l2 tlb miss data (0b)18191e1f3a3f4f51schedule uop (52)schedule int uop (53)schedule simd uop (54)schedule ldst uop (55)dispatch int uop (56)dispatch simd uop (57)dispatch ldst uop (58)int uops in schedulers (59)simd uops in schedulers (5a)ldst uops in schedulers (5b)696d6emap stall dispatch (70)simd prf full (72)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map ldst uop (7d)map simd uop (7e)map int uop inputs (7f)map ldst uop inputs (80)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 tlb miss (a1)a5ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)a9acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1602042671220700000000267010251601001008000080000100800208001550011689511884163266902670926709663606665816013520080020800202008002080020267092670911802011009910010080000100000800000000011151170160026709080000800001002671026710267102671026710
1602042671120800000000267040251601001008000080000100800208001550011689511884163266902670926709663206665816013520080020800202008002080020267132670911802011009910010080000100000800000000011151170160026706080000800001002671026710267102671026714
1602042670920700000000266940251601001008000080000100800208001550011689511884163266902670926709663206665816013520080020800202008002080020267132670911802011009910010080000100000800000003011151170160026710080000800001002671026710267102671026710
1602042670920700000000266940251601001008000080000100800208001550011689511883887266902670926709663206665816013520080020800202008002080020267092670911802011009910010080000100000800000000011151170160026706080000800001002671026710267102671026710
1602042671320700000000266942251601001008000080000100800208001550011689511884163266922670926709663206665816013520080020800202008002080020267092670911802011009910010080000100000800000000011151170160026706080000800001002671026710267102671026710
1602042670920600000000266990251601001008000080000100800208001550011689511884163266902670926709663906665816013520080020800202008002080020267092670911802011009910010080000100000800000003011151170160026706080000800001002671026710267102671026710
1602042670920700000000267090251601001008000080000100800208001550011689511884163266902671026709663206665816013420080020800202008002080020267092670911802011009910010080000100000800000000011151170160026706080000800001002671026710267102671026710
1602042670920700000000266980251601001008000080000100800208001550011689511896532268662671426713663206666216013520080020800202008002080024267092670911802011009910010080000100000800000000011151170160026706080000800001002671026710267102671026710
1602042670920600000000266940251601001008000080000100800208001550011689511884163266902670926709663206665816013520080020800202008002080020267132670911802011009910010080000100000800000100011151170160026706080000800001002671026710267102671026710
1602042670920600000000266940251601001008000080000100800208001550011689511884163266902670926709663206665816013520080020800202008002080020267092670911802011009910010080000100000800000000011151170160026706080000800001002671026710267102671026714

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.3339

retire uop (01)cycle (02)03mmu table walk data (08)09l2 tlb miss data (0b)18191e1f3f4f51schedule uop (52)schedule int uop (53)schedule simd uop (54)schedule ldst uop (55)dispatch int uop (56)dispatch simd uop (57)dispatch ldst uop (58)int uops in schedulers (59)simd uops in schedulers (5a)ldst uops in schedulers (5b)5f60696d6emap stall dispatch (70)simd prf full (72)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map ldst uop (7d)map simd uop (7e)map int uop inputs (7f)map ldst uop inputs (80)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 tlb miss (a1)a5ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)a9acc2cfd5map dispatch bubble (d6)dbddfetch restart (de)e0ea? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1600242670920700000002669402516001010800008000010800008000050116888018840320026690267092670966530366891600102080000800002080000800002670926709118002110910108000010000800000000050201116035267141508000080000102671026710267102671026710
16002426709207000000026694025160010108000080000108000080000501168880188403200266902670926709665303668916001020800008000020800008000026709267091180021109101080000100008000000002506551605326706708000080000102671026710267102671026710
16002426709207000000026695025160010108000080000108000080000501168880188403200266902670926709665303668916001020800008000020800008000026709267091180021109101080000100008000000000502051605326706498000080000102671026710267102671026710
16002426709207000000026697025160010108000080000108000080000501168880188403200266902670926709665303668916001020800008000020800008000026709267091180021109101080000100008000000000502031603526706488000080000102671026710267102671026710
16002426709207000000026694025160010108000080000108000080000501168880188403200266902670926709665303668916001020800008000020800008000026709267091180021109101080000100008000000000502031603526706498000080000102671026710267102671026710
16002426709208000000026694025160010108000080000108000080000501168880188403200266902670926709665303668916001020800008000020800008000026709267091180021109101080000100008000002000502041603626706498000080000102671326710267102671026710
16002427913214001881068704280675743331620901081170811701081489816026112146981942075002790128195280757191179152768016328520817048171620815178151828200280839180021109101080000100029781041002792025202716075278333518000080000102771126722267102671426879
1600242670920700000002819562233416235212810408117014807438142450121913519493870027719280752820472091721667737163289208170481713208189981710282092687810180021109101080000100036080260010793825245510705527982498000080000102820528203282112838327545
16002428326218101591188802281836473341626101080650811701081668816025012186801956823002794528194270407293209165767516292220817048151820817078171028378283271018002110910108000010003298130100078282524279806427978498000080000102820227372280892821028211
160024282012190000000266940251600101080000801301080000805345011688801884032002743427545272126719162133741616255720813328143120815218132927875278729180021109101080000104222480522012609805219512407428167508000080000102836228533285282869328554