RISC-V Is Sloooow

Re:RISC-V Is Sloooow by fidotron on Tuesday March 10, 2026 @05:31PM (#47329041)

The fact the Hazard3 designer ended up creating an extension to resolve related oddities was kind of astonishing.

Why did it fall to them to do it? Impressive that he did, but it shouldn't have been necessary.

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Re:RISC-V Is Sloooow by rllj on Tuesday March 10, 2026 @05:43PM (#47329145)

Which extension is that?

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Re:RISC-V Is Sloooow by mjmas on Tuesday March 10, 2026 @06:00PM (#47329317)

An extension he calls Xh3bextm. For extracting multiple bits from bitfields.

There are also four other custom extensions implemented.

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Re:RISC-V Is Sloooow by wren6991 on Saturday March 14, 2026 @02:51PM (#47379843)

This extension wasn't strictly necessary but it makes decode of Arm instructions faster in the bootrom's Arm emulator.

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