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riscv-non-isa / riscv-c-api-doc

Documentation of the RISC-V C API
https://jira.riscv.org/browse/RVG-4
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Asm constraint to require an even register #37

Open asb opened 1 year ago

asb commented 1 year ago

We don't currently have an asm constraint to require an even register (for an input or output in a register pair) and I don't believe there's a cross-target constraint already defined. We should likely decide on one. This could be used with the proposed zacas extension (amocas.d on rv32 or amocas.q on rv64), for zdinx, and IIRC the P extension.

kito-cheng commented 1 year ago

Good catch, Zdinx still using f in GCC internally, but I think we should have one for P and Zacas

kito-cheng commented 1 year ago

https://github.com/riscv-non-isa/riscv-c-api-doc/pull/39