Apple M1 Microarchitecture Research by Dougall Johnson

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

FSUB (vector, 2S)

Test 1: uops

Code:

  fsub v0.2s, v0.2s, v1.2s
  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)03081e3f4e51inst 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)a0a1a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)f5f6f7f8fd
100430372300612548251000100010003983131301830373037241532895100010002000303730371110011000001073216222630100030383038303830383038
100430372200612548251000100010003983131301830373037241532895100010002000303730371110011000000673216222630100030383038303830383038
100430372300612548251000100010003983131301830373037241532895100010002000303730371110011000000673216222630100030383038303830383038
100430372300612548251000100010003983131301830373037241532895100010002000303730371110011000000073216222630100030383038303830383038
1004303722003212548251000100010003983131301830373037241532895100010002000303730371110011000000073216222630100030383038303830383038
100430372200612548251000100010003983131301830373037241532895100010002000303730371110011000001073216222630100030383038303830383038
100430372300612548251000100010003983131301830373037241532895100010002000303730371110011000000373216222630100030383038303830383038
100430372200612548251000100010003983131301830373037241532895100010002000303730371110011000000973216222630100030383038303830383038
100430372200612548251000100010003983131301830373037241532895100010002000303730371110011000000073216222630100030383038303830383038
100430372300612548251000100010003983131301830373037241532895100010002000303730371110011000000073216222630100030383038303830383038

Test 2: Latency 1->2

Code:

  fsub v0.2s, v0.2s, v1.2s
  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)031e3f4e51inst 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)9facc5branch mispredict (cb)cdcfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
102043003722454612954825101001001000010010000500427731303001830037300372827272874010100200100082002001630037300371110201100991001001000010001117170160029647100001003003830038300383003830038
10204300372250612954825101001001000010010000500427731303001830037300372827272874010100200100082002001630037300371110201100991001001000010001117180160029646100001003003830038300383003830038
10204300372250612954825101001001000010010000500427731303001830037300372827272874010100200100082002001630037300371110201100991001001000010001117170160029646100001003003830038300383003830038
10204300372250612954825101001001000010010000500427731303001830037300372827272874010100200100082002001630037300371110201100991001001000010001117180160029646100001003003830038300383003830038
1020430037225414612954825101001001000010010148500427731303001830037300372827272874010100200100082002001630037300371110201100991001001000010001117170160029646100001003003830038300383003830038
10204300372250612954825101001001000010010000500427731303001830037300372827272874110100200100082002001630037300371110201100991001001000010001117170160029646100001003003830038300383003830038
102043003722506312954825101001001000010010000500427731303001830037300372827272874010100200100082002001630037300371110201100991001001000010001117170160029647100001003003830038300383003830038
10204300372250612954825101001001000010010000500427731303001830037300372827272874110100200100082002001630037300371110201100991001001000010001117170160029647100001003003830038300383003830038
10204300372250612954825101001001000010010000500427731303001830037300372827262874010100200100082002001630037300371110201100991001001000010001117170160029646100001003003830038300383003830038
10204300372250612954825101001001000010010000500427731303001830178300372827262874110100200100082002001630037300371110201100991001001000010001117170160029646100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire (01)cycle (02)03080b18191e1f3a3f4e51inst 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)9fa0a8a9acc2cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
100243003722500004500612954825100101010000101000050427731303001830037300372828732876710010201000020200003003730037111002110910101000010000006402162229630010000103003830038300383003830038
10024300372250000000612954825100101010000101000050427731303001830037300372828732876710010201000020200003003730037111002110910101000010000006402162229630010000103003830038300383003830038
10024300372250000000612954825100101010000101000050427731303001830037300372828732876710010201000020200003003730037111002110910101000010000006402162229630010000103003830038300383003830038
10024300372250000000612954825100101010000101000050427731313001830037300372828732876710010201000020200003003730037111002110910101000010000006402162229630010000103003830038300383003830038
10024300372250000000612954825100101010000101000050427731313001830037300372828732876710010201000020203563003730037111002110910101000010000006402162229630010000103003830038300383003830038
10024300372250000000612954825100101010000101000050427731313001830227300372828732876710010201000020200003003730037111002110910101000010000006402162229630010000103003830038300383003830038
10024300372250000000612954825100101010000101000050427731313001830037300372828732876710010201000020200003003730037111002110910101000010000006402162229630010000103003830038300383003830038
10024300372250000000612954825100101010000101000050427731313001830037300372828732876710010201000020200003003730037111002110910101000010000006402162229630010000103003830038300383003830038
10024300372250000000612954825100101010000101000050427731313001830037300372828732876710010201000020200003003730037111002110910101000010000006402162229630010000103003830038300383003830038
10024300372250000000612954825100101010000101000050427731313001830037300372828732876710010201000020200003003730037111002110910101000010000006402162229630010000103003830038300383003830038

Test 3: Latency 1->3

Code:

  fsub v0.2s, v1.2s, 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)030b191e3f4e51inst 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)9fa8acc5cfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10204300372250012103295482510100100100001001000050042773131300183003730037282653287451010020010000200200003003730037111020110099100100100001000007101161129634100001003003830038300383003830038
1020430037224000103295482510100100100001001000050042773130300183003730037282653287451010020010000200200003003730037111020110099100100100001001289607101161129634100001003003830038300383003830038
10204300372240255282295482510100100100001001000050042773130300183003730037282653287451010020010000200200003003730037111020110099100100100001000007101161129634100001003003830038300383003830038
102043003722500061295482510100100100001001000050042773130300183003730037282653287451010020010000200200003003730037111020110099100100100001000007101161129634100001003003830038300383003830038
102043003722500061295482510100100100001001000050042773131300183003730037282653287451010020010000200200003003730037111020110099100100100001000007101161129634100001003003830038300383003830038
102043003722500061295482510100100100001001000050042773130300183003730037282653287451010020010000200200003003730037111020210099100100100001000007101161129634100001003003830038300383003830038
102043003722500061295482510100100100001001000050042773130300183003730037282653287451010020010000200200003003730037111020110099100100100001000007101161129634100001003003830038300383003830038
102043003722500061295482510100100100001001000050042773130300183003730037282653287451010020010000200200003003730037111020110099100100100001000007101161129634100001003003830038300383003830038
1020430037225000536295482510100100100001001000050042773130300183003730037282653287451010020010000200200003003730037111020110099100100100001000007101161129634100001003003830038300383003830038
102043003722500061295482510100100100001001000050042773130300183003730037282653287451010020010000200200003003730037111020110099100100100001000007101161129634100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire (01)cycle (02)031e3f4e51inst 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)9fa0a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
100243003722506129548251001010100001010000504277313130018030037300372828732876710010201000020200003003730037111002110910101000010000640216222963010000103003830038300383003830038
100243003722506129548251001010100001010000504277313130018030037300372828732876710010201000020200003003730037111002110910101000010000640216222963010000103003830038300383003830038
100243003722506129548251001010100001010000504277313130018030037300372828732876710010201000020203443003730037111002110910101000010000640216222963010000103003830038300383003830038
100243003722506129548251001010100001010000504277313130018030037300372828732876710010201000020200003003730037111002110910101000010000640216222963010000103003830038300383003830038
100243003722506129548251001010100001010000504277313130018030037300372828732876710010201000020200003003730037111002110910101000010000640216222963010000103003830038300383003830038
100243003722506129548251001010100001010000504277313130018030037300372828732876710010201000020200003003730037111002110910101000010000640216222963010000103003830038300383003830038
100243003722406129548251001010100001010000504277313130018030037300372828732876710010201000020200003003730037111002110910101000010000640216222963010000103003830038300383003830038
100243003722506129548251001010100001010000504277313130018030037300372828732876710010201000020200003003730037111002110910101000010000640216222963010000103003830038300383003830038
100243003722506129548251001010100001010000504277313130018030037300372828732876710010201000020200003003730037111002110910101000010000640216222963010000103003830038300383003830038
100243003722406129548251001010100001010000504277313130018030037300372828732876710010201000020200003003730037111002110910101000010000640216222963010000103003830038300383003830038

Test 4: throughput

Count: 8

Code:

  fsub v0.2s, v8.2s, v9.2s
  fsub v1.2s, v8.2s, v9.2s
  fsub v2.2s, v8.2s, v9.2s
  fsub v3.2s, v8.2s, v9.2s
  fsub v4.2s, v8.2s, v9.2s
  fsub v5.2s, v8.2s, v9.2s
  fsub v6.2s, v8.2s, v9.2s
  fsub v7.2s, v8.2s, v9.2s
  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)03081e3f51inst 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)9fa0a8acc2cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
80204200591500041258010010080000100800005006400001200200200392003999733999780100200800002001600002003920039118020110099100100800001000000511021611200360800001002004020040200402004020040
80204200391500041258010010080000100800005006400001200200200392003999733999780100200800002001600002003920039118020110099100100800001000000511011611200360800001002004020040200402004020040
80204200391500041258010010080000100800005006400001200200200392003999733999780100200800002001600002003920039118020110099100100800001000000511011611200360800001002004020040200402004020040
80204200391500041258010010080000100800005006400001200200200392003999733999780100200800002001600002003920039118020110099100100800001000000511011611200360800001002004020040200402004020040
80204200391500041258010010080000100800005006400001200200200392003999733999780100200800002001600002003920039118020110099100100800001000100511011611200360800001002004020040200402004020040
80204201181500041508010010080000100800005006400001200200200392003999733999780100200800002001600002003920039118020110099100100800001000000511011611200360800001002004020040200402004020040
80204200391500641258010010080000100800005006400001200200200392003999733999780100200800002001600002003920039118020110099100100800001000000511011611200360800001002004020040200402004020040
80204200391500041258010010080000100800005006400001200200200392003999733999780100200800002001600002003920039118020110099100100800001000000511011611200360800001002004020040200402004020040
802042003915000516258010010080000100800005006400001200200200392003999733999780100200800002001600002003920039118020110099100100800001000000511011611200360800001002004020040200402004020040
80204200391500041258010010080000100800005006400001200200200392003999733999780100200800002001600002003920039118020110099100100800001000000511011611200360800001002004020040200402004020040

1000 unrolls and 10 iterations

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

retire (01)cycle (02)03191e3f51inst 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
80024200481500040258001010800001080000506400002002020039200399996310019800102080000201600002003920039118002110910108000010005020316372003680000102004020040200402004020040
80024200391500040258001010800001080000506400002002020039200399996310019800102080000201600002003920039118002110910108000010505020216532003680000102004020040200402004020040
800242003915000402580010108000010800005064000020020200392003999963100198001020800002016000020039200391180021109101080000101235020316332003680000102004020040200402004020040
800242003915000402580010108000010800005064000020020200392003999963100198001020800002016000020039200391180021109101080000102835020316322003680000102004020040200402004020040
80024200391500040258001010800001080000506400002002020039200399996310019800102080000201600002003920039118002110910108000010095020316362003680000102004020040200402004020040
800242003914900402580010108000010801055064000020020200392003999963100198001020800002016000020039200391180021109101080000105205020236232003680000102004020040200402004020040
80024200391500040258001010800001080000506400002002020039200399996310019800102080000201600002003920039118002110910108000010005020316352003680000102004020040200402004020040
80024200391500040258001010800001080000506400002002020039200399996310019800102080000201600002003920039118002110910108000010105020516552003680000102004020040200402004020040
800242003915000402580010108000010800005064000020020200392003999963100198001020800002016000020039200391180021109101080000100335020516562003680000102004020040200402004020040
80024200391500040258001010800001080000506400002002020039200399996310019800102080000201600002003920039118002110910108000010035020516232003680000102004020040200402004020040