search for: 1cy

...0). In practice, the llvm scheduling model only allows us to declare which pipeline resources are consumed, and for how long (in number cycles). So we cannot accurately describe to mca that the delayed consumption of the ALU pipe. > Now think about what happens if: the first shuffle uOP consumes 1cy of HWPort0, and the second shuffle uOp consumes 1cy of HWPort1, and the ADD consumes 1cy of HWPort01. We end up in that "odd" situation you described where HWPort01 is "reserved" for 1cy. > In reality, that 1cy of HWPort01 should have started 1cy after the other two opcodes....

..., the llvm scheduling model only allows us to declare which > pipeline resources are consumed, and for how long (in number cycles). So we > cannot accurately describe to mca that the delayed consumption of the ALU > pipe. > Now think about what happens if: the first shuffle uOP consumes 1cy of > HWPort0, and the second shuffle uOp consumes 1cy of HWPort1, and the ADD > consumes 1cy of HWPort01. We end up in that "odd" situation you described > where HWPort01 is "reserved" for 1cy. > In reality, that 1cy of HWPort01 should have started 1cy after the othe...

Hi, I’m trying to work out the behavior of llvm-mca on instructions with ProcResGroups. My current understanding is: When an instruction requests a port group (e.g., HWPort015) and all of its atomic sub-resources (e.g., HWPort0,HWPort1,HWPort5), HWPort015 is marked as “reserved” and is issued in parallel with HWPort0, HWPort1, and HWPort5, blocking future instructions from reserving HWPort015

Hi Andrea, So does this definition make sense for basic blocks with more than one instructions? E.g. how should one interpret a basic block with RThroughput of 2.3? On Fri, Jun 7, 2019 at 7:39 AM Andrea Di Biagio <andrea.dibiagio at gmail.com> wrote: > Hi Tom, > > Field 'Total Cycles' from the summary view simply reports the elapsed > number of cycles for the entire

...able. By the > time the > vmulps is dispatched, operands are already available, and pipeline > JFPU1 is > ready to serve another instruction.  So the instruction can be immediately > issued on the JFPU1 pipeline. That is demonstrated by the fact that the > instruction only spent 1cy in the scheduler's queue. > > There is a gap of 5 cycles between the write-back stage and the retire > event. > That is because instructions must retire in program order, so [1,0] > has to wait > for [0, 2] to be retired first (i.e it has to wait unti cycle 10). > > In...

...become available. By the time the > vmulps is dispatched, operands are already available, and pipeline JFPU1 is > ready to serve another instruction. So the instruction can be immediately > issued on the JFPU1 pipeline. That is demonstrated by the fact that the > instruction only spent 1cy in the scheduler's queue. > > There is a gap of 5 cycles between the write-back stage and the retire > event. > That is because instructions must retire in program order, so [1,0] has to > wait > for [0, 2] to be retired first (i.e it has to wait unti cycle 10). > > In t...

...for the operands to become available. By the time the vmulps is dispatched, operands are already available, and pipeline JFPU1 is ready to serve another instruction. So the instruction can be immediately issued on the JFPU1 pipeline. That is demonstrated by the fact that the instruction only spent 1cy in the scheduler's queue. There is a gap of 5 cycles between the write-back stage and the retire event. That is because instructions must retire in program order, so [1,0] has to wait for [0, 2] to be retired first (i.e it has to wait unti cycle 10). In the dot-product example, all instructio...

...rnally, the Scheduler class delegates the management of processor resource > units and resource groups to the ResourceManager class. ResourceManager is also > responsible for selecting resource units that are effectively consumed by > instructions. For example, if an instruction consumes 1cy of a resource group, > the ResourceManager object selects one of the available units from the group; by > default, it uses a round-robin selector to guarantee that resource usage is > uniformly distributed between all units of a group. To be a cross-subtarget tool, this needs to be a cust...

...e Scheduler class delegates the management of processor > resource > units and resource groups to the ResourceManager class. ResourceManager > is also > responsible for selecting resource units that are effectively consumed by > instructions. For example, if an instruction consumes 1cy of a resource > group, > the ResourceManager object selects one of the available units from the > group; by > default, it uses a round-robin selector to guarantee that resource usage is > uniformly distributed between all units of a group. > > > To be a cross-subtarget tool,...