This prevents the emission of DAG-generated vreg definitions after a
tail call be dropping them entirely (on the grounds that nothing could
use them anyway, and they interfere with O0 CodeGen).
llvm-svn: 185754
// As a special case, a null chain means that a tail call has been emitted and
// the DAG root is already updated.
HasTailCall = true;
+
+ // Since there's no actual continuation from this block, nothing can be
+ // relying on us setting vregs for them.
+ PendingExports.clear();
} else {
DAG.setRoot(Result.second);
}
--- /dev/null
+; RUN: llc -mtriple=thumbv7-linux-gnueabi -O0 -arm-tail-calls < %s | FileCheck %s
+
+; Primarily a non-crash test: Thumbv7 Linux does not have FastISel support,
+; which led (via a convoluted route) to DAG nodes after a TC_RETURN that
+; couldn't possibly work.
+
+declare i8* @g(i8*)
+
+define i8* @f(i8* %a) {
+entry:
+ %0 = tail call i8* @g(i8* %a)
+ ret i8* %0
+; CHECK: b g
+; CHECK-NOT: ldr
+; CHECK-NOT: str
+}