1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-23 19:23:23 +01:00
llvm-mirror/test/tools/llvm-mca/X86/in-order-cpu.s
Andrea Di Biagio 45f0e5261e [llvm-mca] LLVM Machine Code Analyzer.
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
2018-03-08 13:05:02 +00:00

4 lines
173 B
ArmAsm

# RUN: not llvm-mca %s -mtriple=x86_64-unknown-unknown -mcpu=atom -o %t1 2>&1 | FileCheck %s
# CHECK: error: please specify an out-of-order cpu. 'atom' is an in-order cpu.