[llvm-bugs] [Bug 36550] New: Derive TTI instruction costs from scheduling models

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=36550

            Bug ID: 36550
           Summary: Derive TTI instruction costs from scheduling models
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: Windows NT
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: Target Description Classes
          Assignee: unassignedbugs at nondot.org
          Reporter: llvm-dev at redking.me.uk
                CC: a.bataev at hotmail.com, andrea.dibiagio at gmail.com,
                    atrick at apple.com, craig.topper at gmail.com,
                    Florian.Hahn at arm.com, hfinkel at anl.gov,
                    llvm-bugs at lists.llvm.org, spatel+llvm at rotateright.com

As discussed on D43769, we have a very divergent concept of costs between the
different cost models that we use for each target (TTI, scheduling etc.).

It would be very useful to investigate whether we can begin replacing all these
costs tables with values obtained directly from the target scheduling models,
and begin standardizing their usage so that we can use them in more areas than
just vectorization.

This will probably require a target to have models covering most/all of the CPU
types to avoid us, which is why Florian suggested that AArch64 be used for
initial experimentation.

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20180228/c326a87f/attachment.html>