Vectorizer: add tests #14612

Job	Run time
flambda2_runtime5	8m 18s
flambda2_dev	5m 46s
flambda2_dev_runtime5	5m 53s
flambda2_debug_runtime5	7m 31s
flambda2_debug_runtime	7m 2s
flambda2_o3	7m 0s
flambda2_o3_heap	6m 49s
flambda2_o3_advanced_meet_frame_pointers_runtime5_polling	7m 18s
flambda2_o3_advanced_meet_frame_pointers_runtime5_debug	7m 29s
flambda2_frame_pointers_oclassic_polling	7m 56s
flambda2_macos_arm64	5m 50s
flambda2_macos_arm64_irc	7m 14s
flambda2_macos_arm64_ls	6m 16s
flambda2_macos_arm64_gi	8m 18s
irc	7m 10s
irc_polling	7m 36s
irc_frame_pointers	7m 32s
ls	7m 18s
gi	7m 30s
cfg-selection	7m 13s
vectorizer	7m 14s
	2h 30m 13s

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