IMUL (M8) - Throughput and Uops (IACA 2.2)


With a non-indexed addressing mode

With 1 independent instruction

Throughput Analysis Report
--------------------------
Block Throughput: 3.00 Cycles       Throughput Bottleneck: Dependency chains (possibly between iterations)

Port Binding In Cycles Per Iteration:
---------------------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |  6   |  7   |
---------------------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 1.0  | 0.5    0.5  | 0.5    0.5  | 0.0  | 0.0  | 0.0  | 0.0  |
---------------------------------------------------------------------------------------


| Num Of |                    Ports pressure in cycles                     |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |  6  |  7  |    |
---------------------------------------------------------------------------------
|   2^   |           | 1.0 | 0.5   0.5 | 0.5   0.5 |     |     |     |     | CP | imul byte ptr [r14]
Total Num Of Uops: 2

With additional dependency-breaking instructions

Throughput Analysis Report
--------------------------
Block Throughput: 1.00 Cycles       Throughput Bottleneck: Port1

Port Binding In Cycles Per Iteration:
---------------------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |  6   |  7   |
---------------------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 1.0  | 0.5    0.5  | 0.5    0.5  | 0.0  | 0.0  | 0.0  | 0.0  |
---------------------------------------------------------------------------------------


| Num Of |                    Ports pressure in cycles                     |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |  6  |  7  |    |
---------------------------------------------------------------------------------
|   2^   |           | 1.0 | 0.5   0.5 | 0.5   0.5 |     |     |     |     | CP | imul byte ptr [r14]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
Total Num Of Uops: 3

With 16 independent instructions


Throughput Analysis Report
--------------------------
Block Throughput: 48.00 Cycles       Throughput Bottleneck: Dependency chains (possibly between iterations)

Port Binding In Cycles Per Iteration:
---------------------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |  6   |  7   |
---------------------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 16.0 | 8.0    8.0  | 8.0    8.0  | 0.0  | 0.0  | 0.0  | 0.0  |
---------------------------------------------------------------------------------------


| Num Of |                    Ports pressure in cycles                     |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |  6  |  7  |    |
---------------------------------------------------------------------------------
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0x1]
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0x2]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0x3]
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0x4]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0x5]
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0x6]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0x7]
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0x8]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0x9]
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0xa]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0xb]
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0xc]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0xd]
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0xe]
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0xf]
Total Num Of Uops: 32

With additional dependency-breaking instructions

Throughput Analysis Report
--------------------------
Block Throughput: 16.00 Cycles       Throughput Bottleneck: Port1

Port Binding In Cycles Per Iteration:
---------------------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |  6   |  7   |
---------------------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 16.0 | 8.0    8.0  | 8.0    8.0  | 0.0  | 0.0  | 0.0  | 0.0  |
---------------------------------------------------------------------------------------


| Num Of |                    Ports pressure in cycles                     |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |  6  |  7  |    |
---------------------------------------------------------------------------------
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0x1]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0x2]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0x3]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0x4]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0x5]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0x6]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0x7]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0x8]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0x9]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0xa]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0xb]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0xc]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0xd]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+0xe]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2^   |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+0xf]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
Total Num Of Uops: 48

With an indexed addressing mode

With 1 independent instruction

Throughput Analysis Report
--------------------------
Block Throughput: 3.00 Cycles       Throughput Bottleneck: Dependency chains (possibly between iterations)

Port Binding In Cycles Per Iteration:
---------------------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |  6   |  7   |
---------------------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 1.0  | 0.5    0.5  | 0.5    0.5  | 0.0  | 0.0  | 0.0  | 0.0  |
---------------------------------------------------------------------------------------


| Num Of |                    Ports pressure in cycles                     |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |  6  |  7  |    |
---------------------------------------------------------------------------------
|   2    |           | 1.0 | 0.5   0.5 | 0.5   0.5 |     |     |     |     | CP | imul byte ptr [r14+r13*1]
Total Num Of Uops: 2

With additional dependency-breaking instructions

Throughput Analysis Report
--------------------------
Block Throughput: 1.00 Cycles       Throughput Bottleneck: Port1

Port Binding In Cycles Per Iteration:
---------------------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |  6   |  7   |
---------------------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 1.0  | 0.5    0.5  | 0.5    0.5  | 0.0  | 0.0  | 0.0  | 0.0  |
---------------------------------------------------------------------------------------


| Num Of |                    Ports pressure in cycles                     |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |  6  |  7  |    |
---------------------------------------------------------------------------------
|   2    |           | 1.0 | 0.5   0.5 | 0.5   0.5 |     |     |     |     | CP | imul byte ptr [r14+r13*1]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
Total Num Of Uops: 3

With 16 independent instructions


Throughput Analysis Report
--------------------------
Block Throughput: 48.00 Cycles       Throughput Bottleneck: Dependency chains (possibly between iterations)

Port Binding In Cycles Per Iteration:
---------------------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |  6   |  7   |
---------------------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 16.0 | 8.0    8.0  | 8.0    8.0  | 0.0  | 0.0  | 0.0  | 0.0  |
---------------------------------------------------------------------------------------


| Num Of |                    Ports pressure in cycles                     |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |  6  |  7  |    |
---------------------------------------------------------------------------------
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x1]
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x2]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x3]
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x4]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x5]
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x6]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x7]
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x8]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x9]
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xa]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xb]
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xc]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xd]
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xe]
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xf]
Total Num Of Uops: 32

With additional dependency-breaking instructions

Throughput Analysis Report
--------------------------
Block Throughput: 16.00 Cycles       Throughput Bottleneck: Port1

Port Binding In Cycles Per Iteration:
---------------------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |  6   |  7   |
---------------------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 16.0 | 8.0    8.0  | 8.0    8.0  | 0.0  | 0.0  | 0.0  | 0.0  |
---------------------------------------------------------------------------------------


| Num Of |                    Ports pressure in cycles                     |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |  6  |  7  |    |
---------------------------------------------------------------------------------
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x1]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x2]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x3]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x4]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x5]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x6]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x7]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x8]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0x9]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xa]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xb]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xc]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xd]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 | 1.0   1.0 |           |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xe]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
|   2    |           | 1.0 |           | 1.0   1.0 |     |     |     |     | CP | imul byte ptr [r14+r13*1+0xf]
|   1*   |           |     |           |           |     |     |     |     |    | xor rax, rax
Total Num Of Uops: 48

With the -no_interiteration flag

Throughput Analysis Report
--------------------------
Block Throughput: 1.00 Cycles       Throughput Bottleneck: Port1

Port Binding In Cycles Per Iteration:
---------------------------------------------------------------------------------------
|  Port  |  0   -  DV  |  1   |  2   -  D   |  3   -  D   |  4   |  5   |  6   |  7   |
---------------------------------------------------------------------------------------
| Cycles | 0.0    0.0  | 1.0  | 0.5    0.5  | 0.5    0.5  | 0.0  | 0.0  | 0.0  | 0.0  |
---------------------------------------------------------------------------------------


| Num Of |                    Ports pressure in cycles                     |    |
|  Uops  |  0  - DV  |  1  |  2  -  D  |  3  -  D  |  4  |  5  |  6  |  7  |    |
---------------------------------------------------------------------------------
|   2^   |           | 1.0 | 0.5   0.5 | 0.5   0.5 |     |     |     |     | CP | imul byte ptr [r14]
Total Num Of Uops: 2