>Your definition of ‘push’ here is make compulsory Macro-op fusion is entirely optional, leveraged by few hardware implementations; Fusion is useful mostly (i.

>Your definition of ‘push’ here is make compulsory Macro-op fusion is entirely optional, leveraged by few hardware implementations; Fusion is useful mostly (i.e. exceptions exist) only on mid-range cores. High end cores prefer to split everything up (unnecessary on RISC-V), whereas low end cores prefer simpler hardware. Net win in code density weights more in hardware than instruction count, which remains excellent in RISC-V even when the studied microarchitecture does not implement fusion.