Fix broken logic in DominatorTreeBase::Split. Part of PR4238.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72231 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eli Friedman 2009-05-21 21:47:54 +00:00
parent e528fca673
commit 15002a2b52
3 changed files with 9 additions and 42 deletions

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@ -251,49 +251,16 @@ protected:
assert(!PredBlocks.empty() && "No predblocks??");
// The newly inserted basic block will dominate existing basic blocks iff the
// PredBlocks dominate all of the non-pred blocks. If all predblocks dominate
// the non-pred blocks, then they all must be the same block!
//
bool NewBBDominatesNewBBSucc = true;
{
typename GraphT::NodeType* OnePred = PredBlocks[0];
size_t i = 1, e = PredBlocks.size();
for (i = 1; !DT.isReachableFromEntry(OnePred); ++i) {
assert(i != e && "Didn't find reachable pred?");
OnePred = PredBlocks[i];
for (typename GraphTraits<Inverse<N> >::ChildIteratorType PI =
GraphTraits<Inverse<N> >::child_begin(NewBBSucc),
E = GraphTraits<Inverse<N> >::child_end(NewBBSucc); PI != E; ++PI)
if (*PI != NewBB && !DT.dominates(NewBBSucc, *PI) &&
DT.isReachableFromEntry(*PI)) {
NewBBDominatesNewBBSucc = false;
break;
}
for (; i != e; ++i)
if (PredBlocks[i] != OnePred && DT.isReachableFromEntry(OnePred)) {
NewBBDominatesNewBBSucc = false;
break;
}
if (NewBBDominatesNewBBSucc)
for (typename GraphTraits<Inverse<N> >::ChildIteratorType PI =
GraphTraits<Inverse<N> >::child_begin(NewBBSucc),
E = GraphTraits<Inverse<N> >::child_end(NewBBSucc); PI != E; ++PI)
if (*PI != NewBB && !DT.dominates(NewBBSucc, *PI)) {
NewBBDominatesNewBBSucc = false;
break;
}
}
// The other scenario where the new block can dominate its successors are when
// all predecessors of NewBBSucc that are not NewBB are dominated by NewBBSucc
// already.
if (!NewBBDominatesNewBBSucc) {
NewBBDominatesNewBBSucc = true;
for (typename GraphTraits<Inverse<N> >::ChildIteratorType PI =
GraphTraits<Inverse<N> >::child_begin(NewBBSucc),
E = GraphTraits<Inverse<N> >::child_end(NewBBSucc); PI != E; ++PI)
if (*PI != NewBB && !DT.dominates(NewBBSucc, *PI)) {
NewBBDominatesNewBBSucc = false;
break;
}
}
// Find NewBB's immediate dominator and create new dominator tree node for
// NewBB.
NodeT *NewBBIDom = 0;

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@ -1,4 +1,4 @@
; RUN: llvm-as < %s | llc -f -o /dev/null
; RUN: llvm-as < %s | llc -f -o /dev/null -verify-dom-info
%llvm.dbg.anchor.type = type { i32, i32 }
%llvm.dbg.basictype.type = type { i32, { }*, i8*, { }*, i32, i64, i64, i64, i32, i32, i8*, i8* }
%llvm.dbg.compile_unit.type = type { i32, { }*, i32, i8*, i8*, i8* }

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@ -1,4 +1,4 @@
; RUN: llvm-as < %s | opt -lcssa -disable-output
; RUN: llvm-as < %s | opt -lcssa -disable-output -verify-dom-info
; PR977
; END.
declare i32 @opost_block()