[llvm-commits] [llvm] r99282 - in /llvm/trunk: lib/Transforms/Scalar/SimplifyLibCalls.cpp lib/Transforms/Utils/BuildLibCalls.cpp test/Transforms/SimplifyLibCalls/StrCpy.ll

[Evan Cheng]

On Mar 24, 2010, at 9:25 AM, Chris Lattner wrote:

> 
> On Mar 23, 2010, at 8:10 PM, Evan Cheng wrote:
> 
>> 
>> On Mar 23, 2010, at 2:42 PM, Chris Lattner wrote:
>> 
>>> 
>>> On Mar 23, 2010, at 8:48 AM, Evan Cheng wrote:
>>> 
>>>> Author: evancheng
>>>> Date: Tue Mar 23 10:48:04 2010
>>>> New Revision: 99282
>>>> 
>>>> URL: http://llvm.org/viewvc/llvm-project?rev=99282&view=rev
>>>> Log:
>>>> Teach simplify libcall to transform __strcpy_chk to __memcpy_chk to enable optimizations down stream.
>>> 
>>> Hi Evan,
>>> 
>>>> +++ llvm/trunk/lib/Transforms/Scalar/SimplifyLibCalls.cpp Tue Mar 23 10:48:04 2010
>>>> @@ -49,10 +49,13 @@
>>>> Function *Caller;
>>>> const TargetData *TD;
>>>> LLVMContext* Context;
>>>> +  bool OptChkCall;  // True if it's optimizing a *_chk libcall.
>>> 
>>> This is state is not appropriate to add to LibCallOptimization.  If you want to do this, it should be added as a constructor option to StrCpyOpt.
>> 
>> Why is it inappropriate?
> 
> It's inappropriate because you're adding state to LibCallOptimization that only makes sense for StrCpyOpt, please sink it into strcpyopt.

We will be adding other _chk variants. It's common across a large number of string and memory libcalls.

> 
>> I can't add it to the constructor option because optimization objects are ivars. I can't construct it with "StrCpyOpt StrCpyChk(true);". And I don't want to heap allocate them.
> 
> Just initialize it in the ctor, e.g.:
> 
> SimplifyLibCalls() : FunctionPass(&ID), StrCpy(false), StrCpyChk(true) {}

Duh. Of course.

Evan
> 
> -Chris
>