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by gomijacogeo 326 days ago
No, they got rid of the load delay slot in MIPS II. While not required in later ABIs, they kept the branch delay slot for backwards compatibility. MIPS32/MIPS64, which came out much later, also had several new branch instructions without delay slots.

One (probably the only) nifty thing the branch delay slot allowed was in the user-space threads implementation, you didn't have to burn a register for the jump to another thread, you'd do the branch and then clobber the register with the last bit of the jumped-to thread's context. Kinda fiendishly clever.

1 comments

I only meant that MIPS got rid of the "without interlocking pipeline stages" in the R4000, not the other stuff. I was just saying that was a weird architectural feature not unlike BDSs and register windows. BTW, tagged integers are still in SPARC but just for 32b.

I'll have to look up the nifty trick. I have a soft spot for delay slots.