third bug from PR6119: the xor dupe extension allows

for arbitrary terminators in predecessors, don't assume
it is a conditional or uncond branch.  The testcase shows
an example where they can happen with switches.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94323 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2010-01-23 19:21:31 +00:00
parent dbeecede80
commit d668839cb9
2 changed files with 29 additions and 2 deletions

View File

@ -1424,9 +1424,9 @@ bool JumpThreading::DuplicateCondBranchOnPHIIntoPred(BasicBlock *BB,
// Unless PredBB ends with an unconditional branch, split the edge so that we
// can just clone the bits from BB into the end of the new PredBB.
BranchInst *OldPredBranch = cast<BranchInst>(PredBB->getTerminator());
BranchInst *OldPredBranch = dyn_cast<BranchInst>(PredBB->getTerminator());
if (!OldPredBranch->isUnconditional()) {
if (OldPredBranch == 0 || !OldPredBranch->isUnconditional()) {
PredBB = SplitEdge(PredBB, BB, this);
OldPredBranch = cast<BranchInst>(PredBB->getTerminator());
}

View File

@ -286,3 +286,30 @@ for.body: ; preds = %for.cond
br label %for.cond
}
; PR6119
define i32 @test10(i32 %action, i32 %type) nounwind {
entry:
%cmp2 = icmp eq i32 %type, 0 ; <i1> [#uses=1]
switch i32 %action, label %lor.rhs [
i32 1, label %if.then
i32 0, label %lor.end
]
if.then: ; preds = %for.cond, %lor.end, %entry
ret i32 undef
lor.rhs: ; preds = %entry
%cmp101 = icmp eq i32 %action, 2 ; <i1> [#uses=1]
br label %lor.end
lor.end: ; preds = %lor.rhs, %entry
%0 = phi i1 [ %cmp101, %lor.rhs ], [ true, %entry ] ; <i1> [#uses=1]
%cmp103 = xor i1 %cmp2, %0 ; <i1> [#uses=1]
br i1 %cmp103, label %for.cond, label %if.then
for.cond: ; preds = %for.body, %lor.end
br i1 undef, label %if.then, label %for.body
for.body: ; preds = %for.cond
br label %for.cond
}