BSR (R64, M64) - Throughput and Uops (IACA 2.3)


With a non-indexed addressing mode

With 1 independent instruction

Throughput Analysis Report
--------------------------
Block Throughput: 1.00 Cycles       Throughput Bottleneck: FrontEnd

Port Binding In Cycles Per Iteration:
-------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |
-------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 1.0  | 0.5    0.5  | 0.5    0.5  | 0.0  | 0.0  |
-------------------------------------------------------------------------


| Num Of |              Ports pressure in cycles               |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |    |
---------------------------------------------------------------------
|   2^   |           | 1.0 | 0.5   0.5 | 0.5   0.5 |     |     | CP | bsr r8, qword ptr [r14]
Total Num Of Uops: 2

With 8 independent instructions


Throughput Analysis Report
--------------------------
Block Throughput: 8.00 Cycles       Throughput Bottleneck: Backend. Port1

Port Binding In Cycles Per Iteration:
-------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |
-------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 8.0  | 4.0    4.0  | 4.0    4.0  | 0.0  | 0.0  |
-------------------------------------------------------------------------


| Num Of |              Ports pressure in cycles               |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |    |
---------------------------------------------------------------------
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     | CP | bsr r8, qword ptr [r14]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     | CP | bsr r9, qword ptr [r14+0x8]
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     | CP | bsr r10, qword ptr [r14+0x10]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     | CP | bsr r11, qword ptr [r14+0x18]
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     | CP | bsr r12, qword ptr [r14+0x20]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     | CP | bsr rbx, qword ptr [r14+0x28]
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     | CP | bsr rcx, qword ptr [r14+0x30]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     | CP | bsr rdx, qword ptr [r14+0x38]
Total Num Of Uops: 16

With an indexed addressing mode

With 1 independent instruction

Throughput Analysis Report
--------------------------
Block Throughput: 1.00 Cycles       Throughput Bottleneck: FrontEnd

Port Binding In Cycles Per Iteration:
-------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |
-------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 1.0  | 0.5    0.5  | 0.5    0.5  | 0.0  | 0.0  |
-------------------------------------------------------------------------


| Num Of |              Ports pressure in cycles               |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |    |
---------------------------------------------------------------------
|   2    |           | 1.0 | 0.5   0.5 | 0.5   0.5 |     |     | CP | bsr r8, qword ptr [r14+r13*1]
Total Num Of Uops: 2

With 8 independent instructions


Throughput Analysis Report
--------------------------
Block Throughput: 8.00 Cycles       Throughput Bottleneck: Backend. Port1

Port Binding In Cycles Per Iteration:
-------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |
-------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 8.0  | 4.0    4.0  | 4.0    4.0  | 0.0  | 0.0  |
-------------------------------------------------------------------------


| Num Of |              Ports pressure in cycles               |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |    |
---------------------------------------------------------------------
|   2    |           | 1.0 | 1.0   1.0 |           |     |     | CP | bsr r8, qword ptr [r14+r13*1]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     | CP | bsr r9, qword ptr [r14+r13*1+0x8]
|   2    |           | 1.0 | 1.0   1.0 |           |     |     | CP | bsr r10, qword ptr [r14+r13*1+0x10]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     | CP | bsr r11, qword ptr [r14+r13*1+0x18]
|   2    |           | 1.0 | 1.0   1.0 |           |     |     | CP | bsr r12, qword ptr [r14+r13*1+0x20]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     | CP | bsr rbx, qword ptr [r14+r13*1+0x28]
|   2    |           | 1.0 | 1.0   1.0 |           |     |     | CP | bsr rcx, qword ptr [r14+r13*1+0x30]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     | CP | bsr rdx, qword ptr [r14+r13*1+0x38]
Total Num Of Uops: 16