[LLVMdev] tblgen bug in handling case , switch_on

[Sanjiv Gupta]

Mikhail Glushenkov wrote:
> Hi,
>
> On Sat, Sep 5, 2009 at 9:12 PM, Sanjiv Gupta<sanjiv.gupta at microchip.com> wrote:
>   
>> Is the patch below ok?
>>
>> Index: LLVMCConfigurationEmitter.cpp
>> ===================================================================
>> --- LLVMCConfigurationEmitter.cpp    (revision 80668)
>> +++ LLVMCConfigurationEmitter.cpp    (working copy)
>> @@ -1141,6 +1141,7 @@
>>                               Callback, EmitElseIf, OptDescs, O);
>>    }
>>    else {
>> +      EmitElseIf = true;
>>      Callback(arg, (std::string(IndentLevel) + Indent1).c_str(), O);
>>    }
>>    O << IndentLevel << "}\n";
>>     
>
> No, this is not OK - EmitCaseConstructHandler is supposed to be able
> to generate both 'if (...) ... if (...) ... if (...) ...' and 'if
> (...) ... else if (...) ... else ...' forms. That's what the
> EmitElseIf argument controls.
>
> BTW, the example in the documentation generates the 'if (...) ... else
> if (...) ... else ...'  form since the 'case' there is assumed to be
> inside the 'cmd_line' property.
>
> Can you provide a small TableGen code example of what you're trying to
> do which is not working?
>   
I wanted to be able to specify -O0, -O1, -O2 on the mcc16 command line.
And -O2 should be default(if none of -O0 or -O1 is specified). So I made 
following changes to PIC16Base.td, but that didn't work.


def optimizer : Tool<[
 (in_language "llvm-bitcode"),
 (out_language "llvm-bitcode"),
 (output_suffix "bc"),
 (cmd_line "$CALL(GetBinDir)opt $INFILE -o $OUTFILE"),
 (actions (case
          (switch_on "O0"), (append_cmd "-disable-opt"),
          (switch_on "O1"), (append_cmd "-constmerge -globaldce 
-globalopt -ipsccp -jump-threading -simplifycfg -gvn -scalarrepl"),
          (switch_on "O2"), (append_cmd "-constmerge -globaldce 
-globalopt -ipsccp -jump-threading -simplifycfg -gvn -instcombine 
-scalarrepl"),
          (default), (append_cmd "-constmerge -globaldce -globalopt 
-ipsccp -jump-threading -simplifycfg -gvn -instcombine -scalarrepl")))
]>;