llvm dev - Jul 2012 - [LLVMdev] Regarding scope information for variable declaration.

Hi All,
 
I have question regarding lexical scope information.
 
If I have .c source with scope as below. 

void func()
{
   //-- some code here..
   { //parent scope
      if() //high pass
      {
         int i;
         for( i =0; i < FRAM_I; i++)
         {
         }
      }
      if() //low pass
      {
         int i;
         for( i =0; i < FRAM_J; i++)
         {
         }
      }
   }
}

 
In this case, the 'variable i' is not initialized in any of the if
scope, so it should belong to which scope?
Is it ok, if 'scope information' gives me that it belongs to the parent
scope of 'if-scope'?
Is it because the scope information is collected for machine instructions, and
as there will be not machine corresponding to 'int i;', and thus no
scope will be associated with it?
 
Regards,
Pankaj
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I have the same demand. Have you resolved this problems? if so, would you
share me the solution?

Best Regards.

Eric



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Hi Eric,
 I was considering machine instructions to get scope information. And variable
declaration does not correspond to machine instruction, hence the problem i.e.
no scope associated with it. If 'i' is initialized in the
'if-scope' then we get 'variable i' mapped to correct scope as
corresponding machine instruction is generated for this. This is not a problem
as we can't expect variable declaration in a machine instruction, I thought.

S
const Function *F1 =  MF->getFunction();
for(Function::const_iterator BB = F1->begin(), E = F1->end();
                                BB != E; ++BB)
  {
     for(BasicBlock::const_iterator ii = BB->begin(), ie = BB->end();
        ii != ie; ++ii)
     {
        const Instruction *I = ii;  //I->dump();//debug
        DebugLoc MIDB = I->getDebugLoc();
      }
   }
Though this is an overhead as scope information exists, but I need to collect
specific information such as 'start line, end line, start column, end
column' (End line information should be derived as is not obvious).
Collecting information this way allowed me to get correct scope information, and
hence I was able to map the variable declaration to the scope. It worked for me
this way.
 

Regards,
Pankaj
 


________________________________
From: eric.lew <eirc.lew at gmail.com>
To: llvmdev at cs.uiuc.edu 
Sent: Friday, July 12, 2013 8:30 AM
Subject: Re: [LLVMdev] Regarding scope information for variable declaration.


I have the same demand. Have you resolved this problems? if so, would you
share me the solution?

Best Regards.

Eric



--
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http://llvm.1065342.n5.nabble.com/Regarding-scope-information-for-variable-declaration-tp47707p59268.html
Sent from the LLVM - Dev mailing list archive at Nabble.com.
_______________________________________________
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LLVMdev at cs.uiuc.edu        http://llvm.cs.uiuc.edu/
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o instead of using machine instructions to collect scope information, (as used
by LexicalScope pass), I had written code to collect scope information based on
LLVM Instructions. I did this by iterating over
'Function->BasicBlock' instead
of 'MachineFunction->MachineBasicBlock'.
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Hi Eric,
 I was considering machine instructions to get scope information. And variable
declaration does not correspond to machine instruction, hence the problem i.e.
no scope associated with it.
If 'i' is initialized in the 'if-scope' then we get
'variable i' mapped to correct scope as corresponding machine
instruction is generated for this.
This is not a problem as we can't expect variable declaration in a machine
instruction, I thought.

S
I had written code to collect scope information based on LLVM Instructions. 
I did this by iterating over 'Function->BasicBlock' instead
of 'MachineFunction->MachineBasicBlock'.
const Function *F1 =  MF->getFunction();
for(Function::const_iterator BB = F1->begin(), E = F1->end();
                                BB != E; ++BB)
  {
     for(BasicBlock::const_iterator ii = BB->begin(), ie = BB->end();
        ii != ie; ++ii)
     {
        const Instruction *I = ii;  //I->dump();//debug
        DebugLoc MIDB = I->getDebugLoc();
      }
   }
Though this is an overhead as scope information exists, 
but I need to collect specific information such as 'start line, end line,
start column, end column'
(End line information should be derived as is not obvious).
Collecting information this way allowed me to get correct scope information, 
and hence I was able to map the variable declaration to the scope. It worked for
me this way.
 

Regards,
Pankaj

 
 

________________________________
From: eric.lew <eirc.lew at gmail.com>
To: llvmdev at cs.uiuc.edu 
Sent: Friday, July 12, 2013 8:30 AM
Subject: Re: [LLVMdev] Regarding scope information for variable declaration.


I have the same demand. Have you resolved this problems? if so, would you
share me the solution?

Best Regards.

Eric



--
View this message in context:
http://llvm.1065342.n5.nabble.com/Regarding-scope-information-for-variable-declaration-tp47707p59268.html
Sent from the LLVM - Dev mailing list archive at Nabble.com.
_______________________________________________
LLVM Developers mailing list
LLVMdev at cs.uiuc.edu        http://llvm.cs.uiuc.edu/
http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev


o instead of using machine instructions to collect scope information, (as used
by LexicalScope pass),
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