Add c.sext.w and zext.w #290
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Signed-off-by: Afonso Oliveira <[email protected]>
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| @@ -1 +1,3 @@ | |||
| c.zext.w rd_rs1_p 1..0=1 15..13=4 12..10=7 6..5=3 4..2=4 | |||
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| $pseudo_op rv64_c::c.addiw c.sext.w rd_rs1_n0 15..13=1 12=0 6..2=0 1..0=1 | |||
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c.addiw is part of the C extension, not Zcb, so this should be moved to rv64_c.
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I might be wrong here, but c.addiw is identified as part of the c extension by rv64_c::c.addiw and c.sext.w pseudo instruction appears to only be available in rv64_zcb. This is the case in the binutils and in the ISA manual
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It looks like Binutils picks up sext.w as a pseudoinstruction for c.addiw when the C extension is enabled: https://github.com/bminor/binutils-gdb/blob/2754d75a11556577fcddf23718bfbff7d0489a3f/opcodes/riscv-opc.c#L580
But it only picks up c.sext.w as a pseudoinstruction for c.addiw when Zcb is enabled.
This all seems pretty illogical to me, but I guess we are stuck with the binutils behavior at this point for compatibility reasons, right @kito-cheng?
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Although it seems ilogical, my guess is binutils is doing that because the pseudo-instruction is only mentioned as a note on Zcb, maybe if the ISA clarified that, we could change all the others.
I'm now looking on to binutils and the ISA and trying to fix gaps between all the sources.
c.sext.w
zext.w
I also found that this repo doesn't have the any instruction with acquire and release, like "amoswap.b.rl", is there a reason for these, or can i also commit them?