By default, the tool always enables the resource pressure view.
This flag lets user specify whether they want to add that view or not.
llvm-svn: 328305
With this patch, the "instruction dispatched" event now provides information
related to the number of microarchitectural registers used in each register
file. Similarly, the "instruction retired" event is now able to tell how may
registers are freed in each register file.
Currently, the BackendStatistics view is the only consumer of register
usage/pressure information. BackendStatistics uses that info to print out a few
general statistics (i.e. max number of mappings used; total mapping created).
Before this patch, the BackendStatistics was forced to query the Backend to
obtain the register pressure information.
This helps removes that dependency. Now views are completely independent from
the Backend. As a consequence, it should be easier to address PR36663 and
further modularize the pipeline.
Added a couple of test cases in the BtVer2 specific directory.
llvm-svn: 328129
Since r327420, the tool can query the MCSchedModel interface to obtain the
reciprocal throughput information.
As a consequence, method `ResourceManager::getRThroughput`, and
method `Backend::getRThroughput` are no longer needed.
This patch simplifies the code by removing the custom RThroughput computation.
This patch also refactors class SummaryView by removing the dependency with
the Backend object.
No functional change intended.
llvm-svn: 327425
This change removes method Backend::getProcResourceMasks() and simplifies some
logic in the Views. This effectively removes yet another dependency between the
views and the Backend.
No functional change intended.
llvm-svn: 327214
This allows the customization of the performance report.
Users can specify their own custom sequence of views.
Each view contributes a portion of the performance report generated by the
BackendPrinter.
Internally, class BackendPrinter keeps a sequence of views; views are printed
out in sequence when method 'printReport()' is called.
This patch addresses one of the two review comments from Clement in D43951.
llvm-svn: 327018
llvm-mca is an LLVM based performance analysis tool that can be used to
statically measure the performance of code, and to help triage potential
problems with target scheduling models.
llvm-mca uses information which is already available in LLVM (e.g. scheduling
models) to statically measure the performance of machine code in a specific cpu.
Performance is measured in terms of throughput as well as processor resource
consumption. The tool currently works for processors with an out-of-order
backend, for which there is a scheduling model available in LLVM.
The main goal of this tool is not just to predict the performance of the code
when run on the target, but also help with diagnosing potential performance
issues.
Given an assembly code sequence, llvm-mca estimates the IPC (instructions per
cycle), as well as hardware resources pressure. The analysis and reporting style
were mostly inspired by the IACA tool from Intel.
This patch is related to the RFC on llvm-dev visible at this link:
http://lists.llvm.org/pipermail/llvm-dev/2018-March/121490.html
Differential Revision: https://reviews.llvm.org/D43951
llvm-svn: 326998
