/// Turns a llvm.experimental.guard intrinsic into implicit control flow branch,
/// making the following replacement:
///
-/// <code before guard>
+/// --code before guard--
/// call void (i1, ...) @llvm.experimental.guard(i1 %cond) [ "deopt"() ]
-/// <code after guard>
+/// --code after guard--
///
/// into
///
-/// <code before guard>
+/// --code before guard--
/// br i1 %cond, label %guarded, label %deopt
///
/// guarded:
-/// <code after guard>
+/// --code after guard--
///
/// deopt:
/// call void (i1, ...) @llvm.experimental.guard(i1 false) [ "deopt"() ]