if (!N.Val->hasOneUse()) {
std::map<SDOperand, SDOperand>::iterator CGMI = CodeGenMap.find(N);
if (CGMI != CodeGenMap.end()) return CGMI->second;
}
Suppose a DAG like this:
X
^ ^
/ \
USE1 USE2
Suppose USE1 is being selected first and during which X is selected and
returned a new node. After this, USE1 is no longer an use of X. During USE2
selection, X will be selected again since it has only one use!
The fix is to always query CodeGenMap.
llvm-svn: 24679