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

FCVTNS (vector, 2S)

Test 1: uops

Code:

  fcvtns v0.2s, v0.2s
  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)696d6emap 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)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)f5f6f7f8fd
1004303724061254725100010001000398160301830373037241432895100010001000303730371110011000173316222629100030383038303830383038
1004303723661254725100010001000398160301830373037241432895100010001000303730371110011000073216222629100030383038303830383038
1004303724061254725100010001000398160301830373037241432895100010001000303730371110011000073216222629100030383038303830383038
1004303724061254725100010001000398160301830373037241432895100010001000303730371110011000073216222629100030383038303830383038
1004303724061254725100010001000398160301830373037241432895100010001000303730371110011000073216222629100030383038303830383038
10043037231261254725100010001000398160301830373037241432895100010001000303730371110011000073216222629100030383038303830383038
10043037231261254725100010001000398160301830373037241432895100010001000303730371110011000073216222629100030383038303830383038
100430372410261254725100010001000398160301830373037241432895100010001000303730371110011000073216222629100030383038303830383038
1004303724061254725100010001000398160301830373037241432895100010001000303730371110011000073216222629100030383038303830383038
1004303724061254725100010001000398160301830373037241432895100010001000303730371110011000073216222629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtns v0.2s, v0.2s
  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)03mmu table walk data (08)18191e1f3f4e51schedule 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 tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)acc2branch mispred nonspec (cb)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
10204300372330000010329547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100000100071021622296330100001003003830038300383022830038
1020430037232000006129547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100000100071021622296330100001003003830038300383003830038
1020430037232000006129547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100000000071021622296330100001003003830038300383003830038
1020430037233000006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100000000071021622296330100001003003830038300383003830038
1020430037233000006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100000000071021622296330100001003003830038300383003830038
10204300372330000072629547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100000000071021622296330100001003003830038300383003830038
1020430037233000006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100000000071021622296330100001003003830038300383003830038
10204300372410001206129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100000000071021622296330100001003003830038300383003830038
1020430037232000006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100000000071021622296330100001003003830038300383003830038
10204300372330000010329547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100000000071021622296330100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)03l2 tlb miss instruction (0a)181e3f4e51schedule 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 tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
1002430037232013961295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038
100243003723300061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038
100243003723300061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038
1002430037233000481295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038
1002430037232000580295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038
100243003723300061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038
100243003723300061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038
100243003723200061295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038
100243003723300061295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038
100243003723300061295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000000640216222962910000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtns v0.2s, v8.2s
  fcvtns v1.2s, v8.2s
  fcvtns v2.2s, v8.2s
  fcvtns v3.2s, v8.2s
  fcvtns v4.2s, v8.2s
  fcvtns v5.2s, v8.2s
  fcvtns v6.2s, v8.2s
  fcvtns v7.2s, v8.2s
  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)03mmu table walk instruction (07)mmu table walk data (08)l2 tlb miss instruction (0a)18191e1f3f51schedule 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)ld unit uop (a6)l1d cache writeback (a8)acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
80204200581561030000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000011151183161120036800001002004020040200402004020040
80204200391551030000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000011151181161120036800001002004020040200402004020040
80204200391551010000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000011151181161120036800001002025320040200402004020040
80204200391561030000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000011151181161120036800001002004020040200402004020040
80204200391551030000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000011151181161120036800001002004020040200402004020040
80204200391611030000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000011151181161120036800001002004020040200402004020040
80204200391551030000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000011151181161120036800001002004020040200402004020040
80204200391551030000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000011151181161120036800001002004020040200402004020040
80204200391551030000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000011151181161120036800001002004020040200402004020040
80204200391551010000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000011151181161120036800001002004020040200402004020040

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)031e3f51schedule 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)accfd5map dispatch bubble (d6)daddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
8002420050155040258001010800001080000506400001200202003920039999631001980010208000020800002003920039118002110910108000010205020191607112003680000102004020040200402004020040
800242003915505025800101080000108000050640000120020200392003999963100198001020800002080000200392003911800211091010800001000502071601172003680000102004020040201952004020040
80024200391550230258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010005020111601172003680000102004020040200402004020040
8002420039155040258001010800001080000506400001200202003920039999631001980010208000020800002003920039118002110910108000010065020111601172003680000102004020040200402004020040
800242003915504025800101080000108000050640000120020200392003999963100198001020800002080000200392003911800211091010800001000502091601172003680000102004020040200402004020040
800242003915504025800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001010502071607112003680000102004020040200402004020040
80024200391550402580010108000010800005064000002002020039200399996310019800102080000208000020039200391180021109101080000103350201116012122003680000102004020040200402004020249
800242003915504025800101080000108000050640000120020200392003999963100198001020800002080000200392003911800211091010800001000502071607112003680000102004020040200402004020040
8002420039155040258001010800001080000506400001200202003920039999631001980010208000020800002003920039118002110910108000010005020916011122003680000102004020040200402004020040
800242003915604025800101080000108000050640000120020200392003999963100198001020800002080000200392003911800211091010800001003502081608122003680000102004020040200402004020040