Apple M1 Microarchitecture Research by Dougall Johnson

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

UQXTN (S)

Test 1: uops

Code:

  uqxtn h0, s0
  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)a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)f5f6f7f8fd
100430372206125472510001000100039816003018303730372415328951000100010003037303711100110000373116112629100030383038303830383038
100430372206125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372308225472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723031225472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303722039025472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110006073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038

Test 2: Latency 1->2

Code:

  uqxtn h0, s0
  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)0308090b18191e1f3f4e51inst 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)9fa7a8a9acbranch mispredict (cb)cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10204300372250000000189295472510100100100001001000050042771600300183018130037282643287451010020010000200100003003730037111020110099100100100001000000071011611296330100001003003830038300383003830038
1020430084226000006901455295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000500071011611296330100001003003830038300383003830038
1020430037225000000061295478610100110100001031000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001001200071011611296330100001003003830038300383003830038
1020430037225000000061295478010100100100001001000050042771600300183003730037282643287451010020010000200100003003730037511020110099100100100001000000071011611296330100001003003830038300383003830038
1020430037225000000061295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000000071011642296330100001003003830038300383003830038
10204300372250000000103295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000100071011611296330100001003003830038300383003830038
1020430037225000000061295472510100100100001001000050042771601300183003730037282643287451010020010000200100003003730037111020110099100100100001000000071011611296330100001003003830038300383003830038
102043003722500000001032954710010100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000300071011611296330100001003003830038300383003830038
1020430037225000000061295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000100071011611296330100001003003830038300383003830038
1020430037224000000061295472510100100100001001000050042771600300183003730131282643287451010020010000200100003003730037111020110099100100100001000000071011611296330100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire (01)cycle (02)03080b18191e1f3f4e51inst 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)72scheduler 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)9fa1a7a8a9acc2branch mispredict (cb)cdcfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10024300372250000006129547251001010100001010000504277160300183003730037282860262876710010201000020100003003730037111002110910101000010003090006402162229629010000103003830038300383003830038
1002430037225000000612954725100101010000101000050427716030018300373003728286032876710010201000020100003003730037111002110910101000010000030006402162229629010000103003830038300383003830038
1002430037225000000612954725100101010000101000050427716030018300373003728286032876710010201000020100003003730037111002110910101000010005000006402162229629010000103003830038300383003830038
10024300372250000006129547251001010100001010000504277160300183003730037282860328767100102010000201000030037300371110021109101010000100000150006402164329901110000103041330416301703041730416
1002430418228119839979251802954725100101010000101000050427851230018300373003728312042289151136424111412011306301773003711100211091010100001000452248130006402162229629010000103003830038300383003830038
1002430037225000000390529484177100791610056141105067428527230306304643017928317034289171106322113032410652304133041891100211091010100001021390223182108577722329878310000103003830038300383003830038
100243003722500000058342947517410079151005614113506042893283030630458304152829804428916113672411354241131030461302729110021109101010000100020136054008493973529919310000103037230453302743051430464
100243032022810938078806129547251001010100001010000504278512303423041730321283130102891511214241101720109723031930368611002110910101000010001002008292723229834210000103041930414302743046530464
100243032122810105006129547251001010100081210000504277160302703031930367283180172891610915201032520111443017830416611002110910101000010002000006404734329736210000103046630180304633018030180
10024304522270000006129547251002612100641310750814281216301983037030180283150112895410614201098920109783022730509811002110910101000010001000006402162229629010000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  uqxtn h0, s8
  uqxtn h1, s8
  uqxtn h2, s8
  uqxtn h3, s8
  uqxtn h4, s8
  uqxtn h5, s8
  uqxtn h6, s8
  uqxtn h7, s8
  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)031f3f51inst 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)9fa6a7a8acc5branch mispredict (cb)cdcfd5d6inst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
802042005815003025801081008000810080020500640132120020200392003999776999080120200800322008014220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
802042003915003025801081008000810080020500640132120020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
802042003915003025801081008000810080020500640132120020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
802042003915003025801081008000810080020500640132120020200392003999776999080120200800322008003220039200391180201100991001008000010000101115118016020036800001002004020040200402004020040
802042003915003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000131115118016020036800001002004020040200402004020040
802042003915003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
802042003915003025801081008000810080020500640132120020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
802042003915003025801081008000810080020500640132120020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
802042003915003025801081008000810080020500640132120020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
802042003915003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000191115118016020036800001002004020040200402004020040

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)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)9fa0a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
80024200511500402580010108000010800005064000020020200392003999963100198001020800002080000200392003911800211091010800001004950209167102003680000102004020040200402004020040
8002420039150040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100570502010161072003680000102004020040200402004020040
800242003915004025800101080000108000050640000200202003920039999631001980010208000020800002003920039118002110910108000010000502010167102003680000102004020040200402004020040
80024200391500402580010108009710800005064000020020200392003999963100198001020801072080000200392003911800211091010800001002218050208167102003680000102004020040200402004020040
800242003915004025800101080000108000050640000200202003920039999631001980010208000020800002003920039118002110910108000010024050207161072003680000102004020040200402004020040
80024200391500402580010108000010800005064000020020200392003999963100198001020800002080000200392003911800211091010800001001350207168102003680000102004020040200402004020040
80024200391500402580010108000010800005064000020020200392003999963100198001020800002080000200392003911800211091010800001000050207167102003680000102004020040200402004020040
800242003915004025800101080000108000050640000200202003920039999631001980010208000020800002003920039118002110910108000010000502012161292003680000102004020040200402004020040
80024200391500402580010108029110800005064000020020200392003999963100198001020800002080000200392003911800211091010800001002605020121612122003680000102004020040200402004020040
80024200391500402580010108000010800005064000020020200392003999963100198001020800002080000200392003911800211091010800001003205020101612122003680000102004020040200402004020040