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34109687c7
Fix several incorrect backward-compatibility claims in the isCompatible relation that do not reflect actual hardware/spec capabilities. - armv6m: Reverse direction. ARMv6-M (Cortex-M0) is Thumb-only and cannot run full ARMv6 ARM-state code; armv6m code runs on armv6l. https://developer.arm.com/documentation/ddi0432/latest/programmers-model/instruction-set-summary - armv7m: ARMv7-M (Cortex-M3/M4) is Thumb-2 only, cannot run ARM-state armv7l code. armv7a/armv7r (which have ARM-state) can run armv7m code. https://developer.arm.com/documentation/ddi0403/d/Application-Level-Architecture/The-ARMv7-M-Instruction-Set/About-the-instruction-set - armv8m: Remove armv8m->armv8a. ARMv8-M is Thumb-only M-profile with incompatible system registers and exception model. - aarch64<->armv8a: Remove bidirectional equivalence. AArch32 cannot execute A64 instructions. Keep one-directional aarch64->armv8a only. https://developer.arm.com/documentation/dui0801/b/BABBDFIH - armv8r: Remove armv8r->armv8a (and by extension armv8r->aarch64). ARMv8-R is a different profile with MPU (not MMU), a different exception model, and profile-specific instructions. - riscv32->riscv64: Remove. RV64 has no standard RV32 compat mode; identical encodings behave differently at XLEN=32 vs XLEN=64. https://docs.riscv.org/reference/isa/unpriv/rv64.html - wasm32->wasm64: Remove. Separate spec targets with different address types (i32 vs i64); a wasm64 runtime does not accept wasm32 modules. https://github.com/WebAssembly/spec/blob/wasm-3.0/proposals/memory64/Overview.md