I cannot figure out a particular PassManager error for what seem to be
legal dependencies.
Here is the situation. We have 5 passes, RegisterAllocator,
FunctionLiveVarInfo, CoalesceCopies, DominanceForest, and UnionSSAVars,
with dependencies as follows:
class RegisterAllocator : public FunctionPass {
. . .
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<FunctionLiveVarInfo>();
AU.addRequired<CoalesceCopies>();
}
. . .
};
class FunctionLiveVarInfo : public FunctionPass {
. . .
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
}
. . .
};
class CoalesceCopies : public FunctionPass {
. . .
virtual void getAnalysisUsage(AnalysisUsage &AU) {
AU.setPreservesAll();
AU.addRequired<FunctionLiveVarInfo>();
AU.addRequired<UnionSSAVars>();
AU.addRequired<DominanceForest>();
}
. . .
};
class UnionSSAVars : public FunctionPass {
. . .
virtual void getAnalysisUsage(AnalysisUsage &AU) {
AU.setPreservesAll();
AU.addRequired<FunctionLiveVarInfo>();
}
. . .
};
class DominanceForest : public FunctionPass {
. . .
virtual void getAnalysisUsage(AnalysisUsage &AU) {
AU.setPreservesAll();
AU.addRequired<DominatorTree>();
AU.addRequired<UnionSSAVars>();
}
. . .
};
When llc is run (invoking RegisterAllocator), it gives this error message:
Assertion failed: 0 && "Pass available but not found! " "Perhaps this is a
module pass requiring a function pass?", file PassManagerT.h, line 395
Abort
None of the passes here is or requires a module pass. What does the error
message mean, then?
Aqeel Mahesri
