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

SXTL2 (4S)

Test 1: uops

Code:

  sxtl2 v0.4s, v0.8h
  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)ld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)f5f6f7f8fd
10042037150103168625100010001000264521020182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
100420371520761168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
10042037151861168625100010001000264521020182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
1004203715961168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
100420371513861168625100010001000264521020182037203715713189510001000100020372037111001100020073116111786100020382038203820382038
1004203715061168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
1004203715061168625100010001000264521020182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
1004203715061168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
1004203715061168625100010001000264521020182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
10042037165461168625100010001000264521020182037203715713189510001000100020372037111001100000073116111786100020382038203820382038

Test 2: Latency 1->2

Code:

  sxtl2 v0.4s, v0.8h
  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 uop (01)cycle (02)03mmu table walk data (08)l2 tlb miss data (0b)18191e1f3a3f4e51schedule 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)st unit uop (a7)l1d cache writeback (a8)a9acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
1020420037150000000061196862510100100100001001000050028475210200182003720037184213187451010020010000200100002003720037111020110099100100100001000000001320007101161119791100001002003820038200382003820038
1020420037150000000065019686251010010010000100100005002847521020018200372003718421318745101002001000020010000200372003711102011009910010010000100000000840007101161119791100001002003820038200382003820038
10204200371500000000611968625101001001000010010000500284752102001820037200371842131874510100200100002001000020037200371110201100991001001000010000000000007101161119791100001002003820038200382003820038
102042003715000000001281968625101001001000010010000500284752102001820037200371842131874510100200100002001000020037200371110201100991001001000010000000000007101161119791100001002003820038200382003820038
102042003715000000006119686251010010010000100100005002847521020018200372003718421318745101002001000020010000200372003711102011009910010010000100000000720007101161119791100001002003820038200382003820038
10204200371500000000611968625101001001000010010000500284752102001820037200371842131874510100200100002001000020037200371110201100991001001000010000000000007101161119791100001002003820038200382003820038
1020420037150000000061196862510100100100001001000050028475210200182003720037184213187451010020010000200100002003720037111020110099100100100001000000001140007101161119791100001002003820038200382003820038
10204200371500000000611968625101001001000010010000500284752102001820037200371842131874510100200100002001000020037200371110201100991001001000010000000030007101161119791100001002003820038200382003820038
10204200371500000000611968625101001001000010010000500284752102001820037200371842131874510100200100002001000020037200371110201100991001001000010000000000007101161119791100001002003820038200382003820038
10204200371500000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000000007101161119791100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire uop (01)cycle (02)03l2 tlb miss data (0b)18191e1f3a3f4e51schedule 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 tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
10024200371500000006119686251001010100001010000502847521020018020037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
100242003715000000053619686251001010100001010000502847521020018020037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
100242003715000042006119686251001010100001010000502847521020018020037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
10024200371500003006119686251001010100001010000502847521020018020037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
1002420037150000180096419686251001010100001010000502847521020018020037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
1002420037150000013206119686251001010100001010000502847521020018020037200371844331876710010201000020100002003720037111002110910101000010220020156403162219786310000102013420179201802022920181
10024200841510100016119686251001010100001010000502847521020018020037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
10024200371500009006119686251001010100001010000502847521020018020037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
10024200371500000006119686251001010100001010000502847521020018020037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820061200382003820038
10024200371500000006119686251001010100001010000502847521020018020037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038

Test 3: throughput

Count: 8

Code:

  sxtl2 v0.4s, v8.8h
  sxtl2 v1.4s, v8.8h
  sxtl2 v2.4s, v8.8h
  sxtl2 v3.4s, v8.8h
  sxtl2 v4.4s, v8.8h
  sxtl2 v5.4s, v8.8h
  sxtl2 v6.4s, v8.8h
  sxtl2 v7.4s, v8.8h
  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)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)l1d tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
8020420060150000000292580108100800081008002050064013212001920038200389977699898012020080032200800322003820038118020110099100100800001000000000111511801620035800001002003920039200392003920039
8020420038150000000712580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000000000111511801620035800001002003920039200392003920039
8020420038150000000292580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000002000111511801620035800001002003920039200392003920039
8020420038150010000712580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000000000111511801620035800001002003920039200392003920039
80204200381500000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000690111511801620035800001002003920039200392003920039
8020420038150000000292580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000000000111511801620035800001002003920039200392003920039
8020420038150000000712580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000000000111511841620035800001002003920039200392003920039
8020420038150000000292580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000003000111511801620035800001002003920039200392003920039
8020420038150000000292580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000000000111511801620035800001002003920039200392003920039
8020420038150000000292580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000000000111511801620035800001002003920039200392003920039

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03mmu table walk data (08)l2 tlb miss data (0b)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)a9acc2cdcfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)eb? simd retires (ee)? int retires (ef)f5f6f7f8fd
80024200501500000003925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001000000005020031655200350080000102003920039200392003920039
80024200381500000003925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001000526005020041653200350080000102003920039200392003920039
80024200381500000003925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001000000005020051653200350080000102003920039200392003920039
800242003815000000041925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001000200005020031644200350080000102003920039200392003920039
8002420038150000000392580010108000010800005064000012001920038200389996310018800102080000208000020038200981180021109101080000100000153005020051635200350080000102003920039200392003920039
80024200381500000003925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001000000005020041634200350080000102003920039200392003920039
80024200381500000003925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001000000005020041634200350080000102003920039200392003920039
8002420038150000000392580010108000010800005064000012001920038200389996310018800102080000208000020038200381180021109101080000100000111005020041643200350080000102003920039200392003920039
80024200381500000003925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001020000005020031643200350080000102003920039200392003920039
800242003815000000039258001010800001080000506400001200192003820038999631001880010208000020800002003820038118002110910108000010000072005020041643200350080000102003920039200392003920039