[llvm-commits] [llvm] r110423 - in /llvm/trunk: include/llvm/CodeGen/Passes.h include/llvm/Target/TargetInstrInfo.h lib/CodeGen/LLVMTargetMachine.cpp lib/CodeGen/OptimizeCmps.cpp lib/Target/ARM/ARMBaseInstrInfo.cpp lib/Target/ARM/ARMBaseInstrInfo.h

[Bill Wendling]

On Aug 6, 2010, at 10:27 PM, Chris Lattner wrote:

> On Aug 6, 2010, at 6:10 PM, Evan Cheng wrote:
> 
>> On Aug 6, 2010, at 2:24 PM, Chris Lattner wrote:
>> 
>>> On Aug 5, 2010, at 6:32 PM, Bill Wendling wrote:
>>> 
>>>> Author: void
>>>> Date: Thu Aug  5 20:32:48 2010
>>>> New Revision: 110423
>>>> 
>>>> URL: http://llvm.org/viewvc/llvm-project?rev=110423&view=rev
>>>> Log:
>>>> Add the Optimize Compares pass (disabled by default).
>>> 
>>> Why do we need an entire new pass to do this?  Isn't this just a form of CSE?  Why doesn't it go in the MachineCSE pass?
>> 
>> I didn't think of it. That's an interesting idea.
> 
> Ultimately it is never clear of course, but it is really nice to have fewer relatively-coarse grained passes than tons of fine grained ones.
> 
I've been thinking about this. I don't think that this pass should be merged into the CSE pass. It's not really CSE. I *do* agree that this pass (and others, like OptimizeExts and others, should be combined into a single peephole pass.

-bw