[llvm-commits] [llvm] r93338 - in /llvm/trunk/lib/Bitcode/Writer: ValueEnumerator.cpp ValueEnumerator.h

[Victor Hernandez]

On Jan 13, 2010, at 1:00 PM, Devang Patel wrote:

> On Wed, Jan 13, 2010 at 11:36 AM, Victor Hernandez <vhernandez at apple.com> wrote:
> 
>> -void ValueEnumerator::EnumerateMetadata(const MetadataBase *MD) {
>> +void ValueEnumerator::EnumerateMetadata(const MetadataBase *MD, bool isGlobal) {
>>   // Check to see if it's already in!
>>   unsigned &MDValueID = MDValueMap[MD];
>>   if (MDValueID) {
>> @@ -237,14 +237,18 @@
>>   EnumerateType(MD->getType());
>> 
>>   if (const MDNode *N = dyn_cast<MDNode>(MD)) {
>> -    MDValues.push_back(std::make_pair(MD, 1U));
>> -    MDValueMap[MD] = MDValues.size();
>> -    MDValueID = MDValues.size();
>> -    for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
>> -      if (Value *V = N->getOperand(i))
>> -        EnumerateValue(V);
>> -      else
>> -        EnumerateType(Type::getVoidTy(MD->getContext()));
>> +    if ((isGlobal && !N->isFunctionLocal()) ||
>> +        (!isGlobal && N->isFunctionLocal())) {
> 
> What are the cases where isGlobal does not match N->isFunctionLocal()  ?

Prehaps isGlobal is not the best name, it means not-during-function-incorporation.  I think I should improve that variable name.

The case I have encountered is:
1. During ValueEnumerator creation (isGlobal = true), all metadata is iterated over, including those inside of functions, and the isFunctionLocal() metadata needs to be ignored until lazy function incorporation is done.

The other case should be when incorporateFunction (isGlobal = false) comes across a non-function-local metadata.  But in that case the lookup of it in MDValueMap should have succeeded and we will not reach here.

> -
> Devang