I understand now. Shoot.

llvm-svn: 27819
This commit is contained in:
Andrew Lenharth 2006-04-18 22:36:11 +00:00
parent 3823aa1d0f
commit 3e642d012a
1 changed files with 3 additions and 21 deletions

View File

@ -549,30 +549,12 @@ void GraphBuilder::visitCallSite(CallSite CS) {
case Intrinsic::memcpy_i64:
case Intrinsic::memmove_i32:
case Intrinsic::memmove_i64: {
//This is over aggressive. What these functions do is not make the
// targets pointers alias, but rather merge the out edges of the graphs
// for the pointers according to the type merging of the graphs.
//Simply merging the two graphs is a crude approximation to this.
//Instead, copy the src pointer graph, then merge the copy with the
//dest pointer, thus avoiding contaminating the src with info from the dest
//I might be wrong though.
// Merge the first & second arguments, and mark the memory read and
// modified. Preserve second graph
// modified.
DSNodeHandle RetNH = getValueDest(**CS.arg_begin());
DSNodeHandle SrcNH = getValueDest(**(CS.arg_begin()+1));
//copy dsnode
DSNode* copy = new DSNode(*SrcNH.getNode(), SrcNH.getNode()->getParentGraph());
//since this is the target memory, we only are interested in the links.
//the target will not wind up with a global memory object , unless it
//was already there (only pointers to global memory objects)
copy->clearGlobals();
DSNodeHandle Copy( copy, SrcNH.getOffset());
RetNH.mergeWith(Copy);
RetNH.mergeWith(getValueDest(**(CS.arg_begin()+1)));
if (DSNode *N = RetNH.getNode())
N->setModifiedMarker();
if (DSNode *N = SrcNH.getNode())
N->setReadMarker();
N->setModifiedMarker()->setReadMarker();
return;
}
case Intrinsic::memset_i32: