Apple M1 Microarchitecture Research by Dougall Johnson

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

FCMGT (scalar, zero, H)

Test 1: uops

Code:

  fcmgt h0, h0, #0
  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)030b183f4e51inst 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)a0a6a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)f5f6f7f8fd
100420371500611686251000100010002645210201820372037157131895100010001000203720371110011000000073216221786100020382038203820382038
100420371500611686251000100010002645211201820372037157131895100010001000203720371110011000000073216221786100020382038203820382038
1004203715106116862510001000100026452102018203720371571318951000100010002037203711100110000002473216221786100020382038203820382038
100420371501611686251000100010002645211201820372037157131895100010001000203720371110011000001073216221786100020382038203820382038
1004203716001561686251000100010002645211201820372037157131895115210001000203720371110011000000673216221786100020382038203820382038
100420371500611686251000100010002645210201820372037157131895100010001000203720371110011000000073216221786100020382038203820382038
100420371500611686251000100010002645210201820372037157131895100010001000203720371110011000000073216221786100020382038203820382038
1004203716001561686251000100010002645211201820372037157131895100010001000203720371110011000000073216221786100020382038203820382038
100420371600611686251000100010002645210201820372037157131895100010001000203720371110011000000073216221786100020382038203820382038
1004203716001561686251000100010002645211201820372037157131895100010001000203720371110011000000073216221786100020382038203820382038

Test 2: Latency 1->2

Code:

  fcmgt h0, h0, #0
  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 (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)9fa0a6a8acbranch mispredict (cb)cdcfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
102042003715000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000007102162219791100001002003820038200382003820038
1020420037150000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000243007102162219791100001002003820038200382003820038
1020420037150000441196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000010017102162219791100001002003820038200382003820038
102042003715000061196862510100128100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000003007102162219791100001002003820038200382003820038
102042003715000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000090007102162219791100001002003820038200382003820038
102042003715000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000007102162219791100001002003820038200382003820038
102042003715000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000007102162219791100001002003820038200382003820038
1020420037150000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000190007102162219791100001002003820038200382003820038
102042003715000061196862510100100100001001015250028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000010007102162219791100001002003820038200382003820038
102042003715000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000007102162219791100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)030e1e3f4e51inst 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)9fa6a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
100242003715000611968625100611010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010300640216221978610000102003820038200382003820038
100242003715000611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010010640216221978610000102003820038200382003820038
100242003715000611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010010640216221978610000102003820038200382003820038
100242003715009611968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000640216221978610000102003820038200382003820038
100242003715000611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010000640216221978610000102003820038200382003820038
100242003715000611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010013640216221978610000102003820038200382003820038
100242003715000611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010000640216221978610000102003820038200382003820038
1002420037150003461968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010000640216221978610000102003820038200382003820038
1002420037150006119686251001010100001010000502847521020018200372003718443251876710010201000020100002003720037111002110910101000010000640216221978610000102003820038200382003820038
100242003715000611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010000640216221978610000102003820038200382003820038

Test 3: throughput

Count: 8

Code:

  fcmgt h0, h8, #0
  fcmgt h1, h8, #0
  fcmgt h2, h8, #0
  fcmgt h3, h8, #0
  fcmgt h4, h8, #0
  fcmgt h5, h8, #0
  fcmgt h6, h8, #0
  fcmgt h7, h8, #0
  movi v8.16b, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.2506

retire (01)cycle (02)03070a1e3f51inst 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)9fa0a6a8acc5branch mispredict (cb)cdcfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
802042005015111029258010810080008100800205006401320200192003820038997769989801202008003220080032200382003811802011009910010080000100000011151181161120035800001002003920039200392003920039
802042003815011029258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100000011151181161120035800001002003920039200392003920039
8020420038150110138258010810080008100800205006401320200192003820038997769989801202008003220080032200382003811802011009910010080000100001611151181161120035800001002003920039200392003920039
802042003815011092258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100000011151181161120035800001002003920039200392003920039
802042003815011052258010810080008100800205006401320200192003820038997769989801202008003220080032200382003811802011009910010080000100000011151181161120035800001002003920039200392003920039
802042003815011052258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100000011151181161120035800001002003920039200392003920039
802042003815011052258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100020011151181161120035800001002003920039200392003920039
802042003815011029258010810080008100800205006401320200192003820038997769989801202008003220080032200382003811802011009910010080000100000011151181161120035800001002003920039200392003920039
802042003815011029258010810080008100800205006401320200192003820038997769989801202008003220080032200382003811802011009910010080000100000011151181161120035800001002003920039200392003920039
8020420038150110292580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000033011151181161120035800001002003920039200392003920039

1000 unrolls and 10 iterations

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

retire (01)cycle (02)03080b181e3f51inst 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)9fa0a1a6a8a9accfd5d6ddinst fetch restart (de)e0ec? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
800242005115000001042580010108000010800005064000020019200382003899963100188001020800002080000200382003811800211091010800001000000050201161120035080000102003920039200392003920039
80024200381500000392580010108000010800005064000020019200382003899963100188001020800002080000200382003811800211091010800001000000050201161120035080000102003920039200392003920039
800242003815000003972580010108000010800005064000020019200382003899963100188001020800002080000200382003811800211091010800001000000050201161120035080000102003920039200392003920039
80024200381500000602580010108000010800005064000020019200382003899963100188001020800002080000200382003811800211091010800001000000050201161120035080000102003920039200392003920039
800242003815000001232580010108000010800005064000020019200382003899963100188001020800002080000200382003811800211091010800001000000050201161120035080000102003920039200392003920039
8002420038150000181022580010108000010800005064000020019200382003899963100188001020800002080000200382003811800211091010800001000000050201161120035080000102003920039200392003920039
800242003815000001232580010108000010800005064000020019200382003899963100188001020800002080000200382003811800211091010800001000000050201161120035080000102003920039200392003920039
800242003815000005922580010108000010800005064000020019200382003899963100188001020800002080000200382003811800211091010800001000000050201161120035080000102003920039200392003920039
80024200381500000392580010108000010800005064000020019200382003899963100188001020800002080000200382003811800211091010800001000000050201161120035080000102003920039200392003920039
8002420038150000125502580010108000010800005064000020019200382003899963100188001020800002080000200382003811800211091010800001000000050201161120035080000102003920039200392003920039