handleLoops(false, LoopEnd);
}
+ // If the start of the loop is the entry block, we can't branch to it so
+ // insert a new dummy entry block.
+ Function *LoopFunc = LoopStart->getParent();
+ if (LoopStart == &LoopFunc->getEntryBlock()) {
+ LoopStart->setName("entry.orig");
+
+ BasicBlock *NewEntry =
+ BasicBlock::Create(LoopStart->getContext(),
+ "entry",
+ LoopFunc,
+ LoopStart);
+ BranchInst::Create(LoopStart, NewEntry);
+ }
+
// Create an extra loop end node
LoopEnd = needPrefix(false);
BasicBlock *Next = needPostfix(LoopEnd, ExitUseAllowed);
--- /dev/null
+; RUN: opt -S -o - -structurizecfg < %s | FileCheck %s
+
+; CHECK-LABEL: @no_branch_to_entry_undef(
+; CHECK: entry:
+; CHECK-NEXT: br label %entry.orig
+define void @no_branch_to_entry_undef(i32 addrspace(1)* %out) {
+entry:
+ br i1 undef, label %for.end, label %for.body
+
+for.body: ; preds = %entry, %for.body
+ store i32 999, i32 addrspace(1)* %out, align 4
+ br label %for.body
+
+for.end: ; preds = %Flow
+ ret void
+}
+
+; CHECK-LABEL: @no_branch_to_entry_true(
+; CHECK: entry:
+; CHECK-NEXT: br label %entry.orig
+define void @no_branch_to_entry_true(i32 addrspace(1)* %out) {
+entry:
+ br i1 true, label %for.end, label %for.body
+
+for.body: ; preds = %entry, %for.body
+ store i32 999, i32 addrspace(1)* %out, align 4
+ br label %for.body
+
+for.end: ; preds = %Flow
+ ret void
+}