[llvm-commits] Add -arm-long-calls support for ARMFastISel

[Chad Rosier]

Thanks, Jush.  Committed revision 158368.

 Chad

On Jun 12, 2012, at 1:00 AM, Jush Lu wrote:

> Hi Chad,
> 
> The new patch is attached, I moved the BuildMI out the if-else, so
> that BuildMI will be called only once.
> 
> I also moved some duplicate code into a new private function
> "getLibcallReg(const Twin &Name)".
> 
> Thanks,
> Jush
> 
> 
> On Tue, Jun 12, 2012 at 3:54 AM, Chad Rosier <mcrosier at apple.com> wrote:
>> Hi Jush,
>> Overall, LGTM.  When the call is emitted in EmitLibcall is there a difference in the logic when in ARM mode vs. Thumb?
>> 
>> Specifically, this bit of logic:
>>  // Issue the call.
>>  MachineInstrBuilder MIB;
>>  unsigned CallOpc = ARMSelectCallOp(EnableARMLongCalls);
>>  if (isThumb2) {
>>    // Explicitly adding the predicate here.
>>    MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
>>                         TII.get(CallOpc)));
>>    if (EnableARMLongCalls)
>>      MIB.addReg(CalleeReg);
>>    else
>>      MIB.addExternalSymbol(TLI.getLibcallName(Call));
>>  } else {
>>    if (EnableARMLongCalls)
>>      // Explicitly adding the predicate here.
>>      MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
>>                           TII.get(CallOpc))
>>            .addReg(CalleeReg));
>>    else
>>      // Explicitly adding the predicate here.
>>      MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
>>                           TII.get(CallOpc))
>>            .addExternalSymbol(TLI.getLibcallName(Call)));
>>  }
>> 
>> Similarly, in EmitCall can the logic in the else clause be simplified like that in the if (isThumb2) clause?  Specifically, can you make a single call to BuildMI in the else clause for this bit of logic:
>> 
>>  // Issue the call.
>>  MachineInstrBuilder MIB;
>>  unsigned CallOpc = ARMSelectCallOp(UseReg);
>>  if(isThumb2) {
>>    // Explicitly adding the predicate here.
>>    MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
>>                                 TII.get(CallOpc)));
>>    if (UseReg)
>>      MIB.addReg(CalleeReg);
>>    else if (!IntrMemName)
>>      MIB.addGlobalAddress(GV, 0, 0);
>>    else
>>      MIB.addExternalSymbol(IntrMemName, 0);
>>  } else {
>>    if (UseReg)
>>      // Explicitly adding the predicate here.
>>      MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
>>                                   TII.get(CallOpc))
>>            .addReg(CalleeReg));
>>    else if (!IntrMemName)
>>      // Explicitly adding the predicate here.
>>      MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
>>                                   TII.get(CallOpc))
>>            .addGlobalAddress(GV, 0, 0));
>>    else
>>      // Explicitly adding the predicate here.
>>      MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
>>                                   TII.get(CallOpc))
>>            .addExternalSymbol(IntrMemName, 0));
>>  }
>> 
>> 
>>  Chad
>> 
>> On Jun 10, 2012, at 7:59 AM, Jush Lu wrote:
>> 
>>> Hi,
>>> 
>>> I removed some unnecessary variables from the patch in last mail,
>>> please ignore the patch in the last mail, and use the new one attached
>>> in this mail.
>>> 
>>> Thanks,
>>> Jush
>>> 
>>> On Sun, Jun 10, 2012 at 9:30 AM, Jush Lu <jush.msn at gmail.com> wrote:
>>>> Hi,
>>>> 
>>>> This patch adds -arm-long-calls support for ARMFastISel.
>>>> 
>>>> It can generate arm long calls for global functions, runtime library
>>>> calls, and memory intrinsics such as llvm.memset.
>>>> 
>>>> The testtcases in the patch show how they work. Basically, these long
>>>> calls work by blx instructions as the call to non-global callee does
>>>> in r157336.
>>>> 
>>>> Please help me review, thanks.
>>>> 
>>>> Thanks,
>>>> Jush
>>> <ARMFastISel-arm-long-calls.patch>
>> 
> <ARMFastISel-arm-long-calls-06-12.patch>