Apple M1 Microarchitecture Research by Dougall Johnson

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

FMULX (by element, 4S)

Test 1: uops

Code:

  fmulx v0.4s, v0.4s, v1.s[1]
  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)03191e3f4e51inst issue (52)~issue fp/simd (54)~dispatch fp/simd (57)huge thing fp/simd (5b)60696b6d6edispatch 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)a1a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)f5f6f7f8fd
100440373000613407251000100010005319080401804037403732583389510001000200040374037111001100000073116113473100040384038403840384038
100440373100613407251000100010005319080401804037403732583389510001000200040374037111001100000073116113473100040384038403840384038
100440373000613407251000100010005319080401804037403732583389510001000200040374037111001100000073116113473100040384038403840384038
100440373009613407251000100010005319080401804037403732583389510001000200040374037111001100000073116113473100040384038403840384038
1004403730004313407251000100010005319080401804085403732583389510001000200040374037111001100000073116113473100040384038403840384038
100440373000613407251000100010005319080401804037403732583389510001000200040374037111001100000073116113473100040384038403840384038
100440373000823407251000100010005319080401804037403732583389510001000200040374037111001100000073116113473100040384038403840384038
100440373000613407251000100010005319081401804037403732583389510001000200040374037111001100000073116113473100040384038403840384038
100440373100823407251000100010005319080401804037403732583389510001000200040374037111001100000073116113473100040384038403840384038
1004403730045613407251000100010005319080401804037403732583389510001000200040374037111001100000073116113473100040384038403840384038

Test 2: Latency 1->2

Code:

  fmulx v0.4s, v0.4s, v1.s[1]
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 4.0037

retire (01)cycle (02)03181e1f3f4e51inst 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)9fa0a8acc5branch mispredict (cb)cfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10204400373000008239407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100000007101161139479100001004003840038400384003840038
10204400373000006139407251010010010000100101485005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100000007101161139479100001004003840038400384003840038
10204400373000006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100000007101161139479100001004003840038400384003840038
10204400372990006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100000017101161139479100001004003840038400384003840038
10204400373000006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100000007101161139479100001004003840038400384003840038
10204400373000006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100000007101161139479100001004003840038400384003840038
1020440037300133846139407251010010010000100100005005706908140018400374003738108338745101002001016420220000400374003731102011009910010010000100210007101161139479100001004003840038400384003840038
10204400373000006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100000007101161139479100001004003840038400384003840038
10204400372990006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100000007101161139479100001004003840038400384003840038
10204400373000006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100000007101161139479100001004003840038400384003840038

1000 unrolls and 10 iterations

Result (median cycles for code): 4.0037

retire (01)cycle (02)0318191e3f4e51inst 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)9fa8acc2cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10024400372990027111439407251001010100001010000505706908140018400374003738130338767100102010000202000040037400371110021109101010000100006403162239473010000104003840038400384003840038
10024400373000010272639407251001010100001010000505706908140018400374003738130338767100102010000202000040037400371110021109101010000100006402162239473010000104003840038400384003840038
100244003729900396139407251001010100001010000505706908140018400374003738130338767100102010000202000040037400371110021109101010000100006402162239473010000104003840038400384003840038
100244003730000366139407251001010100001010000505706908140018400374003738130338767100102010000202000040037400371110021109101010000100006402162239473010000104003840038400384003840038
100244003729900276139407251001010100001010000505706908140018400374003738130338767100102010000202000040037400371110021109101010000100006402162239473210000104003840038400384003840038
100244003729900516139407251001010100001010000505706908140018400374003738130338767100102010000202000040037400371110021109101010000100006402162239473010000104003840038400384003840038
100244003730000246139407251001010100001010000505706908140018400374003738130338767100102010000202000040037400371110021109101010000100006402162239473010000104003840038400384003840038
100244003730000486139407251001010100001010000505706908140018400374003738130338767100102010000202000040037400371110021109101010000100006402162239473010000104003840038400384003840038
1002440037300003312439407251001010100001010000505706908140018400374003738130338767100102010000202000040037400371110021109101010000100006402162239473010000104003840038400384003840038
100244003730000216139407251001010100001010000505706908140018400374003738130338767100102010000202000040037400371110021109101010000100006402162239473010000104003840038400384003840038

Test 3: Latency 1->3

Code:

  fmulx v0.4s, v1.4s, v0.s[1]
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 4.0037

retire (01)cycle (02)031e1f3f4e51inst 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)9faccfd5d6ddinst fetch restart (de)e0ec? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
1020440037299006139407251010010010000100101485005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100071011611394790100001004003840038400384003840038
1020440037300006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100074011611394792100001004003840038400384003840038
1020440037300006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100071011611394790100001004003840038400384003840038
10204400373000032339407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100071011611394790100001004003840038400384003840038
1020440037300006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100071011611394790100001004003840038400384003840086
1020440037300006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100071011611394790100001004003840038400384003840038
1020440037299006139407251010010010000100100005005706908140018400374003738108338745101002041000020020000400374003711102011009910010010000100071011611394790100001004003840038400384003840038
1020440037300006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100071011611394790100001004003840038400384003840038
1020440037300006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100071011611394790100001004003840038400384003840038
1020440037300006139407251010010010000100100005005706908140018400374003738108338745101002001000020020000400374003711102011009910010010000100071011611394790100001004003840038400384003840038

1000 unrolls and 10 iterations

Result (median cycles for code): 4.0037

retire (01)cycle (02)0318191e3a3f4e51inst 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)9fa8accdcfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
100244003730000222072639407251001010100001010000505706908004001840037400373813033876710010201000020200004003740037111002110910101000010000640316333947310000104003840038400384003840038
100244003730000606139407251001010100001010000505706908004001840037400373813033876710010201000020200004003740037111002110910101000010000640316333947310000104003840038400384003840038
100244003730000006139407251001010100001010000505706908004001840037400373813033876710010201000020200004003740037111002110910101000010000640316333947310000104003840038400384003840038
100244003730000006139407251001010100001010000505706908004001840037400373813033876710010201000020200004003740037111002110910101000010001640316333947310000104003840038400384003840038
100244003730000006139407251001010100001010000505706908004001840037400373813033876710010201000020200004003740037111002110910101000010000640316333947310000104003840038400384003840038
100244003730000006139407251001010100001010000505706908004001840037400373813033876710010201000020200004003740037111002110910101000010000640316333947310000104003840038400384003840038
100244003729900006139407251001010100001010000505706908004001840037400373813033876710010201000020200004003740037111002110910101000010000640316333947310000104003840038400384003840038
100244003730000006139407251001010100001010000505706908004001840037400373813033876710010201000020200004003740037111002110910101000010000640316333947310000104003840038400384003840038
100244003730000008239407251001010100001010000505706908004001840037400373813033876710010201000020200004003740037111002110910101000010000640316333947310000104003840038400384003840038
100244003730000006139407251001010100001010000505706908004001840037400373813033876710010201000020200004003740037111002110910101000010000640316333947310000104003840038400384003840038

Test 4: throughput

Count: 8

Code:

  fmulx v0.4s, v8.4s, v9.s[1]
  fmulx v1.4s, v8.4s, v9.s[1]
  fmulx v2.4s, v8.4s, v9.s[1]
  fmulx v3.4s, v8.4s, v9.s[1]
  fmulx v4.4s, v8.4s, v9.s[1]
  fmulx v5.4s, v8.4s, v9.s[1]
  fmulx v6.4s, v8.4s, v9.s[1]
  fmulx v7.4s, v8.4s, v9.s[1]
  movi v8.16b, 9
  movi v9.16b, 10

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

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

retire (01)cycle (02)030818191e3f51inst 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)9fa8a9accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
80204200601500001542258010010080000100800005006400000200212004020040997339998801002008000020016000020040200401180201100991001008000010000051104162320037800001002004120041200412004120041
8020420040150000042258010010080000100800005006400000200212004020040997339998801002008000020016000020040200401180201100991001008000010000051102162320037800001002004120041200412004120041
80204200401500002142258010010080000100800005006400001200212004020040997339998801002008000020016000020040200401180201100991001008000010000051101163320037800001002004120041200412004120041
80204200401500000422580206100801021168000050064000002002120040200409973310010801002008000020016000020040200401180201100991001008000010000051102163320037800001002004120041200412004120041
80204200401500002142258010010080000100800005006400001200212004020040997339998801002008000020016000020040200401180201100991001008000010000051103163320037800001002004120041200412004120041
80204200401500002142258010010080000100800005006400000200212004020040997339998801002008000020016000020040200401180201100991001008000010000051103163220037800001002004120041200412004120041
80204200401500002442258010010080000100800005006400000200212004020040997339998801002008000020016000020040200401180201100991001008000010000051103163320037800001002004120041200412004120041
80204200401500002442258020010080000100800005006400001200212004020040997339998801002008000020016000020040200401180201100991001008000010000051103163320037800001002004120041200412004120041
80204200401500002142258022610080000100800005006400000200212004020040997339998801002008000020016000020040200401180201100991001008000010000051102162320037800001002004120041200412004120041
80204200401500002742258010010080000100800005006400000200212004020040997339998801002008000020016000020040200401180201100991001008000010000051102162320037800001002004120041200412004120041

1000 unrolls and 10 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)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)9fcfd5d6daddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
80024200401501541258001010800001080000506400001200212004020040999631002080010208000020160000200402004011800211091010800001050205160242003780000102004120041200412004120041
8002420040150041258001010800001080000506400000200212004020040999631002080010208000020160000200402004011800211091010800001050202160242003780000102004120041200412004120041
8002420040150041258001010800001080000506400000200212004020040999631002080010208000020160000200402004011800211091010800001050204160422003780000102004120041200412004120041
8002420040150962258001010800001080000506400001200212004020040999631002080010208000020160000200402004011800211091010800001050204160422003780000102004120041200412004120041
80024200401501841258001010800001080000506400000200212004020040999631002080010208000020160000200402004011800211091010800001050204160422003780000102004120041200412004120041
8002420040150041258001010800001080000506400000200212004020040999631002080010208000020160000200402004011800211091010800001050204160442003780000102004120041200412004120041
8002420040150041258001010800001080000506400001200212004020040999631002080010208000020160000200402004011800211091010800001050202160242003780000102004120041200412004120041
8002420040150041258001010800001080000506400000200212004020040999631002080010208000020160000200402004011800211091010800001050202160242003780000102004120041200412004120041
8002420040150041258001010800001080000506400001200212004020040999631002080010208000020160000200402004011800211091010800001050204160422003780000102004120041200412004120041
8002420040150041258001010800001080000506400000200212004020040999631002080010208000020160000200402004011800211091010800001050204160432003780000102004120041200412004120041