[LLVMbugs] [Bug 13122] New: Need unit test driver for codegen IR passes.

[bugzilla-daemon at llvm.org]

http://llvm.org/bugs/show_bug.cgi?id=13122

             Bug #: 13122
           Summary: Need unit test driver for codegen IR passes.
           Product: new-bugs
           Version: trunk
          Platform: PC
        OS/Version: All
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: new bugs
        AssignedTo: unassignedbugs at nondot.org
        ReportedBy: atrick at apple.com
                CC: llvmbugs at cs.uiuc.edu
    Classification: Unclassified


This is a well know problem, but I didn't find any existing PRs in a quick
search.

We're currently unable to develop unit tests for codegen IR passes because they
require TargetLowering info.

I'd like to be able to run LSR unit tests as "opt -loop-reduce t.ll" and
FileCheck the IR output. But we need a way to tell opt how to instantiate
TargetLowering.

I haven't tried to figure out how to implement it, but it seems we may have two
choices

- Have opt instantiate a dummy TLI that are close enough to x86_64/armv7. It
needs to have a few working APIs, such as isLegalAddressingMode.

- Generate the real TLI for a given target. This probably requires linking
libCodegen. So we may need to use llc as the driver, but teach it to run
individual passes the way opt does today.

-- 
Configure bugmail: http://llvm.org/bugs/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.