Add benchmark for heterogenous tuples/array literals

Ref. JuliaLang/julia#39035

Author: Seelengrab

src/misc/MiscellaneousBenchmarks.jl

@@ -398,4 +398,12 @@ perf_g6() = sum([+(a,b,c,d,e,f) for a in 1:4, b in 1:4, c in 1:4, d in 1:4, e in
 
 SUITE["perf highdim generator"] = @benchmarkable perf_g6()
 
+#############################################
+# Performance of heterogenous tuples #39035 #
+#############################################
+
+perf_het_tuple() = b = [1, 2.0]
+
+SUITE["perf heterogenous tuple"] = @benchmarkable perf_het_tuple()
+
 end