Apple M1 Microarchitecture Research by Dougall Johnson

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

SQSHLU (vector, 2S)

Test 1: uops

Code:

  sqshlu v0.2s, v0.2s, #3
  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)030b1e3f4e51inst 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)a6a8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)f5f6f7f8fd
10042037150061168625100010001000264521120182037203715713189510001000100020372037111001100001073116111786100020382038203820382038
10042037150061168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
10042037160061168625100010001000264521120542037203715713189510001000100020372037111001100000073116111786100020382038203820382038
100420371501261168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
10042037150061168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
10042037150061168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
10042037150061168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
100420371501261168625100010001000264521120182037203715713189510001000100020372085111001100000073116111786100020382038203820382038
10042037150061168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038
10042037150661168625100010001000264521120182037203715713189510001000100020372037111001100000073116111786100020382038203820382038

Test 2: Latency 1->2

Code:

  sqshlu v0.2s, v0.2s, #3
  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)033f4e51inst 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)9fa8accfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
10204200371506119686251010010010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100007101161119791100001002003820038200382003820038
10204200371506119686251010010010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100007101161119791100001002003820038200382003820038
10204200371506119686251010010010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100007101161119791100001002003820038200382003820038
10204200371506119686251010010010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100007101161119791100001002003820038200382003820038
10204200371506119686251015110010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100237101161119791100001002003820038200382003820038
10204200371506119686251010010010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100007101161119791100001002003820038200382003820038
10204200371506119686251010010010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100207101161119791100001002003820038200382003820038
10204200371506119686251010010010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100007101161119791100001002003820038200382003820038
10204200371506119686251010010010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100007101161119791100001002003820038200382003820038
10204200371506119686251010010010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100107101161119791100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire (01)cycle (02)030408090b18191e1f3f4e51inst 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)9fa0a1a6a7a8a9acc2cfd5d6ddinst fetch restart (de)e0? int output thing (e9)? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
100242003715010000000611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010000000006403162219786010000102003820038200382003820038
1002420037150000000120611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010000000006402162219786010000102003820038200382003820038
100242003715000000000611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010000000006402162219786010000102003820038200382003820038
100242003715000000030611968625100101010000101000050284752112001820037200371844331878810468201000020100002003720037111002110910101000010000000006402162219786010000102003820038200382003820038
100242003715001000000611968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000000006402162219786010000102003820038200382003820038
100242003715000000000611968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000000006402162219786010000102003820038200382003820038
10024200371500000001350611968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000000006402162219786010000102003820038200382003820038
100242003715000000000611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010000000006402162219786010000102003820038200382003820038
100242003715000000000611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010000000006402162219786010000102003820038200382003820038
1002420037150000000390611968625100101010000101000050284752112001820037200371844331876710010201000020100002003720037111002110910101000010000000006402162219786010000102003820038200382003820038

Test 3: throughput

Count: 8

Code:

  sqshlu v0.2s, v8.2s, #3
  sqshlu v1.2s, v8.2s, #3
  sqshlu v2.2s, v8.2s, #3
  sqshlu v3.2s, v8.2s, #3
  sqshlu v4.2s, v8.2s, #3
  sqshlu v5.2s, v8.2s, #3
  sqshlu v6.2s, v8.2s, #3
  sqshlu v7.2s, v8.2s, #3
  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)0308090b18191e1f203f51inst 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)9fa1a6a8acc2c5branch mispredict (cb)cdcfd5d6e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
8020420061150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511801620035800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132120019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511801620035800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132120019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511801620035800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511801620035800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511801620035800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132120019200382003899776998980120200800322008003220038200381180201100991001008000010000100111511801620035800001002003920039200392003920039
8020420038150000000002943802081008000810080020500640132120019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511801620035800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511801620035800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511801620035800001002003920039200392003920039
8020420038150000000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000111511801620035800001002003920039200392003920039

1000 unrolls and 10 iterations

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

retire (01)cycle (02)03090b3f51inst 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)9fa8a9acc5cfd5d6ddinst fetch restart (de)e0? fp/simd (ee)gpr retires (ef)f5f6f7f8fd
8002420050150003925800101080000108000050640000020019200382003899963100188001020800002080000200382003811800211091010800001000305020316362003580000102003920039200392003920039
8002420038150003925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001000005020216232003580000102003920039200392003920039
8002420038150003925800101080000108000050640000120100200392003899963100188001020800002080000200382003811800211091010800001000005020316352003580000102003920039200392003920039
8002420038150003925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001000005020216322003580000102003920039200392003920039
8002420038150013925800101080000108000050640000020019200382003899963100188001020800002080000200382003811800211091010800001000005020316322003580000102003920039200392003920039
8002420038150003925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001000605020516552003580000102003920039200392003920039
8002420038150003925800101080000108000050640000020019200382003899963100188001020800002080000200382003811800211091010800001000005020316652003580000102003920039200392003920039
8002420038150003925800101080000108000050640000120019200382003899963100188001020800002080000200382003811800211091010800001000005020216232003580000102003920039200392003920039
80024200381500013425800101080000108000050640000020019200382003899963100188001020800002080000200382003811800211091010800001000005020316322003580000102003920039200392003920039
8002420038150003925800101080000108000050640000020019200382003899963100188001020800002080000200382003811800211091010800001020005020516332003580000102003920039200392003920039