feat(#851): aarch64 direct call lowering (bl + R_AARCH64_CALL26)#859
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avrabe wants to merge 4 commits into
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feat(#851): aarch64 direct call lowering (bl + R_AARCH64_CALL26)#859avrabe wants to merge 4 commits into
call lowering (bl + R_AARCH64_CALL26)#859avrabe wants to merge 4 commits into
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Lower WASM direct `call` on the -b aarch64 backend: - encoder: bl (imm26), stp/ldp FP+LR non-leaf frame primitives - selector: select_typed_cf_calls threads num_imports/arg/result counts; marshals args to x0..x7 (AAPCS64), bl func_N, pushes x0 result; non-leaf prologue saves LR. Loud-declines imports, >8 args, multi/float results, param-across-call, and any live stack below the args. - backend: compile_module places ALL local functions (func_N symbols + export aliases); emits R_AARCH64_CALL26 relocations - elf: .rela.text section (ELF64 r_info sym in high word, type 283) - core: DecodedModule.func_result_counts (0/1 result distinction); RelocKind::AArch64Call26 Leaf functions byte-identical. 7 new selector tests + 2 elf tests. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01YJK5LZZEkV5smCY1jKn18L
…+ differential
Integration + soundness follow-up to the call lowering:
- The CLI drives a per-function compile loop (not backend::compile_module), so
thread call metadata via CompileConfig: add func_result_counts (0/1 result),
populated in both the single-module and WAST-merged decode paths.
- Fix build_multi_func_aarch64_elf / build_aarch64_elf for the new
A64ElfFunction {symbols, code, relocations}: emit func_N for EVERY function
(the CALL26 target) + export alias, and FORWARD relocations (were dropped).
- SOUNDNESS: loud-decline a callee that returns f32/f64 — AAPCS64 returns
floats in v0/d0, not x0; pushing x0 would be a silent miscompile. Threads
func_ret_float into the selector. New selector test.
- Differential (scripts/repro/aarch64_calls_851.py): native arm64 MAP_JIT,
resolves R_AARCH64_CALL26 itself, 5 call modules (const/computed args, void,
i64, result-consumed) bit-identical vs wasmtime. Asserts every expected
symbol is present (a silently-declined caller fails loudly, never hangs on an
unrelocated bl #0).
- CHANGELOG [Unreleased] entry.
RED (origin/main): "unsupported wasm op for aarch64 subset: Call" + caller
skipped. GREEN: 5/5 bit-identical. Frozen ARM anchors 10/10 untouched;
aarch64_matrix.sh unchanged (32 ops/86 checks PASS).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YJK5LZZEkV5smCY1jKn18L
Add scripts/repro/aarch64_calls_851.py as a step in the aarch64-native-matrix job (macos-latest arm64 — has clang + wasm-tools + wasmtime). The standing matrix is single-function and cannot exercise calls; this harness JITs linked multi-function blobs and diffs vs wasmtime, failing loudly if any expected symbol is missing (a silently-declined caller). Static strings only. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01YJK5LZZEkV5smCY1jKn18L
…lf + 1 encoder) Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01YJK5LZZEkV5smCY1jKn18L
Codecov Report❌ Patch coverage is 📢 Thoughts on this report? Let us know! |
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Lane L3 of the v0.51 hub. Lowers WASM direct
callon the-b aarch64backend (previously a loud-decline). Ref #851.What was lowered
Direct
call— args marshalled intox0..x7per AAPCS64,bl func_Nto the callee (linkable via a newR_AARCH64_CALL26.rela.textrelocation),x0result pushed. A function that emits a call becomes NON-LEAF: it saves/restores FP+LR (stp x29,x30,[sp,#-16]!/ldp x29,x30,[sp],#16) around the body. Leaf functions stay byte-identical (the frame is gated on "body has a lowered call").The multi-function object now places every reachable local function with a
func_Nsymbol (+ export alias) so a call to a non-exported helper resolves.Honest frontier (loud-declined, never wrong code)
call_indirect(the named residual)Changes
bl(imm26),stp_fp_lr_pre16,ldp_fp_lr_post16— clang-ground-truth-verifiedselect_typed_cf_callsthreads num_imports / arg / result / float-return; marshals + emits bl + records call sites; non-leaf LR framefunc_result_counts+func_ret_floatthreaded; relocations produced;compile_moduleplaces all locals.rela.text(ELF64r_infosym in high word, type 283); multi-symbol-per-functionRelocKind::AArch64Call26;DecodedModule::func_result_counts;CompileConfig::func_result_countsfunc_result_counts(single + WAST-merged paths); fixbuild_multi_func_aarch64_elfto emitfunc_N+ forward relocationsGate evidence (RED → GREEN)
RED (origin/main):
unsupported wasm op for aarch64 subset: Call(1)— the exported caller is skipped, absent from the object.GREEN:
scripts/repro/aarch64_calls_851.py(native arm64 MAP_JIT, resolves the CALL26 relocations itself) — 5 call modules bit-identical vs wasmtime (const args, computed args, void call, i64 call, result-consumed). Asserts every expected symbol is present, so a silently-declined caller fails loudly (never hangs on an unrelocatedbl #0). Wired into theaarch64-native-matrixCI job..rela.text+ 1 encoder (76 backend tests pass)aarch64_matrix.shunchanged (32 ops / 86 checks PASS — calls aren't in its op-set)-D warningsclean on aarch64/core/cli;--features riscvbuilds🤖 Generated with Claude Code
https://claude.ai/code/session_01YJK5LZZEkV5smCY1jKn18L