Apple M1 Microarchitecture Research by Dougall Johnson

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

FNEG (scalar, H)

Test 1: uops

Code:

  fneg h0, h0
  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)696d6edispatch 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
100420371524611686251000100010002645212018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150611686251000100010002645212018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150611686251000100010002645212018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150611686251000100010002645212018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150611686251000100010002645212018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150611686251000100010002645212018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150611686251000100010002645212018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150611686251000100010002645212018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150611686251000100010002645212018203720371571318951000100010002037203711100110000073116111786100020382038203820382038
10042037150611686251000100010002645212018203720371571318951000100010002037203711100110000073116111786100020382038203820382038

Test 2: Latency 1->2

Code:

  fneg h0, h0
  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)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)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)9facc5branch mispredict (cb)cdcfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10204200371500611968625101001001000010010000500284752120018200372003718428718741101002001000820010180200372003711102011009910010010000100011171701600198000100001002003820038200382003820038
10204200371500611968625101001001000010010000500284752120018200372003718428618741101002001000820010008200372003711102011009910010010000100000071011611197910100001002003820038200382003820038
102042003715021611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071011611197910100001002003820038200382003820038
102042003715024611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071011611197910100001002003820038200382003820038
102042003715039611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071011611197910100001002003820038200382003820038
102042003715039611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071011611197910100001002003820038200382003820038
102042003715021611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071011611197910100001002003820038200382003820038
102042003715021611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071011611197910100001002003820038200382003820038
102042003715066611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071011611197910100001002003820038200382003820038
102042003715012611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071011611197910100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)0307080a18191e1f3a3f4e51inst 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)9fa0a6a7a8acc2cdcfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
1002420037150101003750268196862510010101000010100005028475210200182003720037184433187671001020100002010000200372003711100211091010100001000000006441016101019786010000102003820038200382003820038
10024200371501010060268196862510010101000010100005028475211200182003720037184433187671001020100002010000200372003711100211091010100001000000006441016101019786010000102003820038200382003820038
10024200371501010000268196862510010101000010100005028475210200182003720037184433187671001020100002010000200372003711100211091010100001000000006441016101019786010000102003820038200382003820038
1002420037150101004740268196862510010101000010100005028475210200182003720037184433187671001020100002010000200372003711100211091010100001000000006441016101019786010000102003820038200382003820038
1002420037150101000026819686251001011100121010000502847521020018200372003718443318767100102010000201000020037200371110021109101010000100000000644111610519786010000102003820038200382003820038
1002420037150101000026819686251001010100001010000502847521020018200372003718443318767100102010000201000020037200371110021109101010000100000000644101651019786010000102003820038200382003820038
100242003715010100630268196862510010101000010100005028475210200182003720037184433187671001020100002010000200372003711100211091010100001000000006441016101019786010000102003820038200382003820038
100242003715010100240268196862510010101000010100005028475210200182003720037184433187671001020100002010000200372003711100211091010100001000000006441016101119786010000102003820038200382003820038
10024200371501010000268196862510010101000010100005028475210200182003720037184433187671001020100002010000200372003711100211091010100001000000006441016101019786010000102003820038200382003820038
10024200371501010015026819686251001010100001010000502847521020018200372003718443318767100102010000201000020037200371110021109101010000100000000644101610519786010000102003820038200382003820038

Test 3: throughput

Count: 8

Code:

  fneg h0, h8
  fneg h1, h8
  fneg h2, h8
  fneg h3, h8
  fneg h4, h8
  fneg h5, h8
  fneg h6, h8
  fneg h7, h8
  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)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)9fa8acc5branch mispredict (cb)cdcfd6dde0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
802042006015002052580208100801001008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010000111513416020035800001002003920039200392003920039
80204200381500292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010000111511816020035800001002003920039200392003920039
802042003815030292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010000111511816020035800001002003920039200392003920039
802042003815021292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010000111511816020035800001002003920039200392003920039
80204200381500292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010000111511816020035800001002003920039200392003920039
80204200381500292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010000111511816020035800001002003920039200392003920039
80204200381500292580108100800081008002050064072420019200382003899776998980120200800322008003220038200381180201100991001008000010000111511816020035800001002003920039200392003920039
80204200381500292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010000111511816020035800001002003920039200392003920039
802042003815021292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010000111511816020035800001002003920039200392003920039
80204200381500292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010000111511816020035800001002003920039200392003920039

1000 unrolls and 10 iterations

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

retire (01)cycle (02)031e1f3f51inst 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)9fa6a8accdcfd0d2d5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
80024200501503303925800101080000108000050640000102001920038200389996310018800102080000208000020038200381180021109101080000100000502000116112003580000102003920039200392003920039
8002420038150003925800101080000108000050640000002001920038200389996310018800102080000208000020038200381180021109101080000100001502000116112003580000102003920039200392003920039
800242003815045603925800101080000108000050640000102001920038200389996310018800102080000208000020038200381180021109101080000100000502000116112003580000102003920039200392003920039
8002420038150003925800101080000108000050640000102001920038200389996310018800102080000208000020038200381180021109101080000100030502000116112003580000102003920039200392003920039
8002420038150003925800101080000108000050640000102001920038200389996310018800102080000208000020038200381180021109101080000100000502000116112003580000102003920039200392003920039
8002420038150003925800101080000108000050640000102001920038200389996310018800102080000208000020038200381180021109101080000100000502000116112003580000102003920039200392003920039
800242003815038103925800101080000108000050640724102001920038200389996310018800102080000208000020038200381180021109101080000100000502000116112003580000102003920039200392003920039
8002420038150003925800101080000108000050640000102001920038200389996310018800102080000208000020038200381180021109101080000100000502000116112003580000102003920039200392003920039
800242003815024903925800101080000108000050640000102001920038200389996310018800102080000208000020038200381180021109101080000100000502000116112003580000102003920039200392003920039
8002420038150003925800101080000108000050640000102001920038200389996310018800102080000208000020038200381180021109101080000100000502000116112003580000102003920039200392003920039