Apple M1 Microarchitecture Research by Dougall Johnson

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

FCMEQ (vector, zero, 4H)

Test 1: uops

Code:

  fcmeq v0.4h, v0.4h, #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)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)cfd5d6ddinst fetch restart (de)e0? fp/simd (ee)f5f6f7f8fd
10042037165161168625100010001000264521120182037203715713189510001000100020372037111001100073116111786100020382038203820382038
1004203715061168625100010001000264521020182037203715713189510001000100020372037111001100073116111786100020382038203820382038
1004203716061168625100010001000264521020182037203715713189510001000100020372037111001100073116111786100020382038203820382038
100420371511161168625100010001000264521120182037203715713189510001000100020372037111001100073116111786100020382038203820382038
1004203716061168625100010001000264521020182037203715713189510001000100020372037111001100073116111786100020382038203820382038
10042037159961168625100010001000264521020182037203715713189510001000100020372037111001100073116111786100020382038203820382038
1004203715061168625100010001000264521120182037203715713189510001000100020372037111001100073116111786100020382038203820382038
1004203715061168625100010001000264521020182037203715713189510001000100020372037111001100073116111786100020382038203820382038
1004203716061168625100010001000264521120182037203715713189510001000100020372037111001100073116111786100020382038203820382038
1004203715061168625100010001000264521020182037203715713189510001000100020372037111001100073116111786100020382038203820382038

Test 2: Latency 1->2

Code:

  fcmeq v0.4h, v0.4h, #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)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)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)9fa0a1a6a7a8a9acc2c5branch mispredict (cb)cdcfd0d5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
102042003715000001500611968625101001001000010010000500284752120018200372003718428231874110100200100082001000820037200371110201100991001001000010000000002111718001600198010100001002003820038200382003820038
1020420037150000000061196862510100100100001001000050028475212001820037200371842871874010100200100082001000820037200371110201100991001001000010000000000111718001600198000100001002003820038200382003820038
1020420037150000000061196862510100100100001001000050028475212001820037200371842871874010100200100082001000820037200371110201100991001001000010000000000111717001600198000100001002003820038200382003820038
1020420037150000000061196862510100100100001001000050028475212001820037200371842861874010100200100082001000820037200371110201100991001001000010000000000111718001600198000100001002003820038200382003820038
1020420037150000000061196862510100100100001001000050028475212001820037200371842131874510100200100002001000020037200371110201100991001001000010000000000000710011611197910100001002003820038200382003820038
1020420037150000000061196862510100100100001001000050028475212001820228200371842131874510100200100002001000020037200371110201100991001001000010000000000000710011611197910100001002003820038200382003820038
1020420037150000000061196862510100100100001001000050028475212001820037200371842131874510100200100002001000020037200371110201100991001001000010000000000000710011611197910100001002003820038200382003820038
1020420037150000000061196862510100100100001001000050028475212001820037200371842131874510100200100002001000020037200371110201100991001001000010000000000000710011611197910100001002003820038200382003820038
1020420037150000000061196862510100100100001001000050028475212001820037200371842131874510100200100002001000020037200371110201100991001001000010000000000000710011611197910100001002003820038200382003820038
1020420037150000000061196862510100100100001001000050028475212001820037200371842131874510100200100002001000020037200371110201100991001001000010000000000000710011611197910100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)030b181e1f3f4e51inst 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)9fa0a6a8a9acbranch mispredict (cb)cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
100242003715000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
100242003715000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
1002420037150000034619686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100000006402162219786110000102003820038200382003820038
100242003716000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
100242003715000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
100242003715000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100000199506402162219786010000102003820038200382003820038
10024200371510012886119686251001010100001010000502847521120018200372003718443318767101632010000201000020037200371110021109101010000100010906402162219786210000102003820038200382003820038
1002420037149009071119686251001010100121010000502848785120018200372003718443318785100102010000201000020037200371110021109101010000100410306402162219786010000102008520038200382003820038
1002420037150011206119686251001010100001110000502847521120018200372003718443318767101662010000201000020037200371110021109101010000100010006402162219786210000102003820038200382003820038
1002420037150103006119686251003710100121010000502847521120018200372003718443318767100102010000201000020084200371110021109101010000100000006402162219786010000102003820038200382003820038

Test 3: throughput

Count: 8

Code:

  fcmeq v0.4h, v8.4h, #0
  fcmeq v1.4h, v8.4h, #0
  fcmeq v2.4h, v8.4h, #0
  fcmeq v3.4h, v8.4h, #0
  fcmeq v4.4h, v8.4h, #0
  fcmeq v5.4h, v8.4h, #0
  fcmeq v6.4h, v8.4h, #0
  fcmeq v7.4h, v8.4h, #0
  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)030408090b18191e1f3f51inst 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)9fa0a6a8acc2c5branch mispredict (cb)cdcfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
80204200591500000000088425801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511821622200350800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511811621200350800001002003920039200392003920039
8020420038150000000005025801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511831621200350800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511811612200350800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511821612200350800001002003920039200392003920039
8020420038150000000602925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511821612200350800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511821621200350800001002003920039200392003920039
80204200381500000000050425801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511821612200350800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000100111511811612200350800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511811621200350800001002003920039200392003920039

1000 unrolls and 10 iterations

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

retire (01)cycle (02)03191e3a3f51inst 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)9fa8acc2cfd5d6daddinst fetch restart (de)e0ea? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
8002420039150000392580010108000010800005064000002001902003820038999631001880010208000020800002003820038118002110910108000010000502011601120035080000102003920039200392003920039
8002420038150000392580010108000010800005064000012001902003820038999631001880010208000020800002003820038118002110910108000010000502011601120035080000102003920039200392003920039
8002420038150000392580010108000010800005064000002001902003820038999631001880010208000020800002003820038118002110910108000010000502011601120035080000102003920039200392003920039
8002420038150000392580010108000010800005064000002001902003820038999631001880010208000020800002003820038118002110910108000010400502011601120035080000102003920039200392003920039
80024200381501003925800101080188108009750640000120019020038200381000431004580010208009620800002003820038118002110910108000010000502011601120035080000102003920039200392003920039
8002420038150000392580010108000010800005064000002001902003820038999631001880010208000020800002003820038118002110910108000010000502011601120035080000102003920039200392003920039
8002420038150000392580010108000010800005064000002001902003820038999631001880010208000020800002003820038118002110910108000010000502011601120035080000102003920039200392003920039
8002420038150090392580010108000010800005064000012001902003820038999631001880010208000020800002003820038118002110910108000010000502011601120035080000102003920039200392003920039
8002420038150000392580010108000010800005064000002001902003820038999631001880010208000020800002003820038118002110910108000010000502011601120035080000102003920039200392003920039
8002420038150000392580010108000010800005064000012001902003820038999631001880010208000020800002003820038118002110910108000010000502011601120035080000102003920039200392003920039