Softfloat on riscv64 - #38
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Seed the rv64gc baseline (base, d, c, a) for riscv64 in ConfigureInstructionSetSupport - previously no baseline was declared, so with a runtime that models F/D/C/A as instruction sets every riscv64 build would look like a no-F target and silently flip to the soft-float ABI. For the zisk/zisk_sim flavors append -c,-a,-f,-d to --targetisa: dropping C/A stops compressed/atomic emission through the same instruction-set mechanism as the EnableRiscV64* knobs, and dropping F/D switches ilc and the JIT into the lp64 soft-float ABI and soft-float lowering (dotnet-riscv fixup patches 26-28). Explicit --targetisa values keep working - the reduction is appended on top. Signed-off-by: Maxim Menshikov <maksim.menshikov@nethermind.io>
The nofp module models the FP-free contract: every soft-float builtin traps and the whole libm surface is wrapped to traps. With the JIT now lowering FP into soft-float calls (dotnet-riscv fixups 26-28) a no-F build needs those symbols to work instead: - modules/softfloat: vendored compiler-rt builtins (llvmorg-18.1.8, Apache-2.0 WITH LLVM-exception) compiled strictly for rv64im via the new multi-file module mechanism (module_srcs.lst + module_cflags in build.sh: plain ELF objects merged with ld -r, no LTO so the builtins are never re-codegenned with the common rv64imad flags), plus soft replacements for the hard-float runtime conversion helpers (RhpDbl2Lng family, .NET saturating semantics) and vendored musl fmod/fmodf (MIT, pure bit manipulation), all diverted with --wrap. - BuildCommand: a riscv64 target without the F instruction set links softfloat.o instead of nofp.o and drops the nofp libm wraps. The libm surface itself still resolves to hard-float musl members and remains guarded by --error-on-float-binary until a soft-float libm ships. - bflat.variant.props: pin the .NET 11 min variant to the v11.0.0.x11-sf runtime release, which carries the soft-float runtime patches and the RiscV64_F instruction set in the compiler package. Signed-off-by: Maxim Menshikov <maksim.menshikov@nethermind.io>
…shutdown Two fixes found while bringing up soft-float execution on ziskemu: 1. patch_elf writes its output to Path.ChangeExtension(output, .patched) and bflat never moved it back, nor checked the exit code. Guest recipes historically passed -o <name>.patched, which made ChangeExtension a no-op and the script overwrite its input in place - with any other output name the user received the RAW linker output, which does not boot on the zkVM (unfixed .tdata flags/init_array type/bss layout make the loader jump through a zero slot at __libc_start_init). Move the result over the requested output and fail the build on postprocess errors. 2. The zkVM decodes only base rv64im: extend the zisk instruction-set reduction with -zba,-zbb,-zbs,-zicond and force the corresponding EnableRiscV64* JIT knobs (plus F/D for hygiene) off. The cross-JIT resolves ISAs through the altjit path where every knob defaults to on, independent of ilc instruction-set support - Zicond notably turned GT_SELECT into czero.* encodings. Also: BFLAT_NO_ZK_ISA_REDUCTION / BFLAT_NO_RISCV_BASELINE env escape hatches used for bisection, kept for diagnostics. Signed-off-by: Maxim Menshikov <maksim.menshikov@nethermind.io>
… pin x13-sf The libziskos nupkg places its manifest under contentFiles/any/any/ while runtimes/<rid>/native/ sits at the package root, so the manifest-relative static-library path missed it. Walk up towards the extraction root and take the first match. Pin the .NET 11 min variant to v11.0.0.x13-sf (soft-float runtime with the ReturnTypeDesc FP-struct-return gate). Keep the bisection env hatches (BFLAT_NO_ZK_ISA_REDUCTION / BFLAT_NO_RISCV_BASELINE) documented in-line. Signed-off-by: Maxim Menshikov <maksim.menshikov@nethermind.io>
The compiler package for the .NET 10 variants has no RiscV64_F enum member and its instruction-set tables know nothing of f/d/c/a, so the zisk ISA reduction and the soft-float switch must not assume them. Probe a throwaway InstructionSetSupportBuilder for "f" support and resolve the enum member reflectively; on older packages the reduction is skipped and the classic nofp path is linked, exactly as before the soft-float work. Signed-off-by: Maxim Menshikov <maksim.menshikov@nethermind.io>
Review feedback: module_cflags was a second ad-hoc side file next to module_params.yml. Fold it into the existing declarative params as an options.cc section (same '- value:' entry style as options.ld) and read it in build.sh with yq like the other module options. The softfloat module is the only consumer; behavior is unchanged. Signed-off-by: Maxim Menshikov <maksim.menshikov@nethermind.io>
…ms.yml Review feedback: module_cflags and module_srcs.lst were ad-hoc side files next to the module's declarative params. Fold both into module_params.yml as options.sources / options.cc sections (same '- value:' entry style as options.ld) and read them in build.sh with yq like the other module options. The softfloat module is the only consumer; behavior is unchanged. Signed-off-by: Maxim Menshikov <maksim.menshikov@nethermind.io>
The ACSL gate requires every defined function in a C module to carry a contract. Annotate the .NET conversion semantics (NaN -> 0, saturation bounds) on the Rhp wrappers and put declaration specs on the renamed musl fmod/fmodf definitions; Frama-C attaches a declaration contract to the definition the include pulls in. Locally: check_acsl.py reports softfloat 8/8 ok. Signed-off-by: Maxim Menshikov <maksim.menshikov@nethermind.io>
The compiler package now models the lp64 (soft-float) calling convention as TargetAbi.NativeAotRiscV64SoftFloat (dotnet-riscv fixup 27): the JIT flag and the ELF float-ABI marker follow the ABI rather than the F instruction set. Select it whenever the target lacks F or D, resolving the member reflectively so that older packages keep building. Signed-off-by: Maxim Menshikov <maksim.menshikov@nethermind.io>
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