Fix incorrect description of the calling convention for floats passed in GPRs #998
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Thanks for the quick review - I've pushed a tweaked version of the commit. |
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… in GPRs As I noted previously in <riscvarchive/riscv-zfinx#14>, it's incorrect to say that floating point values passed in GPRs are sign-extended in the standard calling convention. The [current, ratified psABI](https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/6cda8927232dc59424426f4dd0de2e0723d865fb/riscv-cc.adoc) states "Floating-point reals are passed the same way as aggregates of the same size" and the relevant part from the description of aggregates is "Bits unused due to padding, and bits past the end of an aggregate whose size in bits is not divisible by XLEN, are undefined."
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Manually applying commit #998. As I noted previously in <riscvarchive/riscv-zfinx#14>, it's incorrect to say that floating point values passed in GPRs are sign-extended in the standard calling convention. The [current, ratified psABI](https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/6cda8927232dc59424426f4dd0de2e0723d865fb/riscv-cc.adoc) states "Floating-point reals are passed the same way as aggregates of the same size" and the relevant part from the description of aggregates is "Bits unused due to padding, and bits past the end of an aggregate whose size in bits is not divisible by XLEN, are undefined."
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As I noted previously in riscvarchive/riscv-zfinx#14, it's incorrect to say that floating point values passed in GPRs are sign-extended in the standard calling convention. The current, ratified psABI states "Floating-point reals are passed the same way as aggregates of the same size" and the relevant part from the description of aggregates is "Bits unused due to padding, and bits past the end of an aggregate whose size in bits is not divisible by XLEN, are undefined."