///
Loop *LoopSimplify::SeparateNestedLoop(Loop *L, LPPassManager &LPM,
BasicBlock *Preheader) {
- // Don't try to separate loops without a preheader (this excludes
- // loop headers which are targeted by an indirectbr).
+ // Don't try to separate loops without a preheader.
if (!Preheader)
return 0;
// handles the case when a PHI node has multiple instances of itself as
// arguments.
SmallVector<BasicBlock*, 8> OuterLoopPreds;
- for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
+ for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
if (PN->getIncomingValue(i) != PN ||
- !L->contains(PN->getIncomingBlock(i)))
+ !L->contains(PN->getIncomingBlock(i))) {
+ // We can't split indirectbr edges.
+ if (isa<IndirectBrInst>(PN->getIncomingBlock(i)->getTerminator()))
+ return 0;
OuterLoopPreds.push_back(PN->getIncomingBlock(i));
-
+ }
+ }
DEBUG(dbgs() << "LoopSimplify: Splitting out a new outer loop\n");
// If ScalarEvolution is around and knows anything about values in
--- /dev/null
+; RUN: opt < %s -loop-simplify -S | FileCheck %s
+
+; Make sure the preheader exists.
+; CHECK: sw.bb103:
+; CHECK: indirectbr {{.*}}label %while.cond112
+; CHECK: while.cond112:
+; But the tail is not split.
+; CHECK: for.body:
+; CHECK: indirectbr {{.*}}label %while.cond112
+define fastcc void @build_regex_nfa() nounwind uwtable ssp {
+entry:
+ indirectbr i8* blockaddress(@build_regex_nfa, %while.cond), [label %while.cond]
+
+while.cond: ; preds = %if.then439, %entry
+ indirectbr i8* blockaddress(@build_regex_nfa, %sw.bb103), [label %do.body785, label %sw.bb103]
+
+sw.bb103: ; preds = %while.body
+ indirectbr i8* blockaddress(@build_regex_nfa, %while.cond112), [label %while.cond112]
+
+while.cond112: ; preds = %for.body, %for.cond.preheader, %sw.bb103
+ %pc.0 = phi i8 [ -1, %sw.bb103 ], [ 0, %for.body ], [ %pc.0, %for.cond.preheader ]
+ indirectbr i8* blockaddress(@build_regex_nfa, %Lsetdone), [label %sw.bb118, label %Lsetdone]
+
+sw.bb118: ; preds = %while.cond112
+ indirectbr i8* blockaddress(@build_regex_nfa, %for.cond.preheader), [label %Lerror.loopexit, label %for.cond.preheader]
+
+for.cond.preheader: ; preds = %sw.bb118
+ indirectbr i8* blockaddress(@build_regex_nfa, %for.body), [label %while.cond112, label %for.body]
+
+for.body: ; preds = %for.body, %for.cond.preheader
+ indirectbr i8* blockaddress(@build_regex_nfa, %for.body), [label %while.cond112, label %for.body]
+
+Lsetdone: ; preds = %while.cond112
+ unreachable
+
+do.body785: ; preds = %while.cond, %while.body
+ ret void
+
+Lerror.loopexit: ; preds = %sw.bb118
+ unreachable
+}