Apple M1 Microarchitecture Research by Dougall Johnson

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

UCVTF (vector, integer, 2S from 2S)

Test 1: uops

Code:

  ucvtf 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 (01)cycle (02)031e3f4e51inst issue (52)~issue fp/simd (54)~dispatch fp/simd (57)huge thing fp/simd (5b)60696d6edispatch 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)a8acc2cfd5d6ddinst fetch restart (de)e0? fp/simd (ee)f5f6f7f8fd
10043037230156254725100010001000398160030183037303724143289510001000100030373037111001100003073216222629100030383038303830383038
10043037230170254725100010001000398160030183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
10043037230103254725100010001000398160030183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
10043037231261254725100010001000398160130183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
10043037240251254725100010001000398160130183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
1004303724061254725100010001000398160030183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
10043037232161254725100010001000398160130183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
1004303723061254725100010001000398160130183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
1004303723061254725100010001000398160130183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
1004303723061254725100010001000398160130183037303724143289510001000100030373037111001100000073216222629100030383038303830383038

Test 2: Latency 1->2

Code:

  ucvtf 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 (01)cycle (02)0308090b18191e1f3a3f4e51inst 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)60696b6d6edispatch 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)9fa0a1a6a8a9acc2cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10204300372330000000061295472510100100100001001000050042771600300180300373003728264328745101002001000020010000300373003711102011009910010010000100000200071011611296330100001003003830038300383003830038
10205300372330000000061295472510100100100001001000050042771600300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000071011611296330100001003003830038300383003830038
10204300372320000000061295472510100100100001001000050042771600300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000071011611296330100001003003830038300383003830038
10204300372330000000061295472510100100100001001000050042771600300180300373003728264328745101002001000020010000302333003711102011009910010010000100000000071011611296330100001003003830038300383003830038
102043003723200000000652295472510100100100001001000050042771601300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000071011611296330100001003003830038300383003830038
10204300372330000000061295472510100100100001001000050042771601300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000071011611296330100001003003830038300383003830038
102043003723200000000726295472510100100100001001000050042771600300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000071011611296330100001003003830038300383003830038
10204300372330000000061295472510100100100001001000050042771601300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000071011611296330100001003003830038300383003830038
10204300372330000000061295472510100100100001001000050042771600300180300373003728264328745101002001000020010499300373003711102011009910010010000100000000071011611296330100001003003830038300383003830038
10204300372330000000061295472510100100100001001000050042771601300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000071011611296330100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire (01)cycle (02)03181e3f4e51inst 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)9fa0a6a8a9accfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
1002430037233001032954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003723200612954725100101010000101000050427716013001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
1002430037233001172954725100101010000101000050427716013001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003723300612954725100101010000101000050427716013001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003723300612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003723300612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003723300612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000206402162229629010000103003830038300383003830038
1002430037233002052954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
1002430037232008102954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003723300612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  ucvtf v0.2s, v8.2s
  ucvtf v1.2s, v8.2s
  ucvtf v2.2s, v8.2s
  ucvtf v3.2s, v8.2s
  ucvtf v4.2s, v8.2s
  ucvtf v5.2s, v8.2s
  ucvtf v6.2s, v8.2s
  ucvtf 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 (01)cycle (02)03181e1f3f51inst 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)9fa8a9acc5branch mispredict (cb)cdcfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
8020420060155015303025801081008000810080020500640132020020200392003999776999080447200800322008003220039200391180201100991001008000010000011151180160020036800001002004020040200402004020040
802042003915508703025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000311151180160020036800001002004020040200402004020040
802042003915605703025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000011151180160020036800001002004020040200402004020040
80204200391550003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000011151180160020036800001002004020040200402004020040
802042003915504503025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000011151180160020036800001002004020040200402004020040
802042003915503603025801081008000810080020500640132020020200392003999776999080124200800322008003220039200391180201100991001008000010000011151180160020036800001002004020040200402004020040
80204200391550003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000011151180160020036800001002004020040200402004020040
80204200391560003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000011151180160020036800001002004020040200402004020040
80204200391550003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010002611151180160020036800001002004020040200402004020040
80204200391560003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010010311151180160020036800001002004020040200402004020040

1000 unrolls and 10 iterations

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

retire (01)cycle (02)0307191e3f51inst 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)696d6edispatch 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)9fa8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
800242005015500046258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100350201416522003680000102004020040200402004020040
800242003916100040258001010800001080000506400002002020076200399996310019800102080000208000020039200391180021109101080000100050204161152003680000102004020040200402004020040
80024200391550004025800101080000108000050640000200202003920039999631001980010208000020800002003920039118002110910108000010005020416642003680000102004020040200402004020040
800242003915600082258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100350201016642003680000102004020040200402004020040
8002420039156000402580010108000010800005064000020020200392003999963100198001020800002080000201392003911800211091010800001000502051611102003680000102004020040200402004020040
800242003915610040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100050201016652003680000102004020040200402004020040
80024200391550004025800101080000108000050640000200202003920039999631001980010208000020800002003920039118002110910108000010005020416452003680000102004020040200402004020040
800242003915600040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100050205164122003680000102004020040200402004020040
800242003915500040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100050204161062003680000102004020040200402004020040
800242003915500040258001010800001080000506400002002020039200399996310074800102080000208000020039200391180021109101080000100050201116862003680000102004020040200402004020040