About

During an evaluation of the GDB test suite on RISC-V, it was discovered that the GDB Simulator (used by the GDB test suite) only supports RV64G and RV32G models.

This work will add support for the C extension (compressed instructions, Zc), allowing for RV64GC and RV32GC models to be selected and ran. This is important because many of the C libraries that can be used when building GDB make use of Zc instructions. (Also CSR instructions are not properly handled).

Status

Updates

Aug 15, 2023 

• Reported commencement of development effort

Oct 5, 2023 

• The scope of this task has increased to include support for single and double precision floating point and to provide some semihosting facilities

• With these additions, it is anticipated that the GDB test suite will have 100% successful coverage on RISC-V

• This takes us into early Q4 (end of October)

Oct 17, 2023 

• Initial patches submitted upstream

Mar 6, 2024 

• Marking as completed

  • Zc support merged to master in https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=3224e32fb84f034d190ad91d7b9ac86f6800d47a

  • Additional patches for F and D simulation submitted at https://sourceware.org/pipermail/gdb-patches/2024-February/206827.html