cmd/compile: encode linkname pulls in LLVM symbol names - #131
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Go compiler-generated builtin references and source-level linkname pulls can target the same canonical Go symbol while requiring different GoObj reference identities. This change makes the LLVM symbol name the complete reference contract: - `<builtin.N>` identifies a GoObj builtin reference and embeds its authoritative Go builtin index. - `<linkname>` identifies a source linkname pull. - `<ABI0>` remains an orthogonal, outer suffix. - definitions keep their canonical names. - malformed or conflicting suffix/metadata combinations fail closed. GoObj strips the reference suffix, writes builtin references as `PkgIdxBuiltin`, and writes linkname pulls as non-package references with `SymFlagLinkname`. The standard-library bit is also carried through `!goobj.config`, which is required for linker authorization of `//go:linknamestd` pulls from LLVM-built runtime objects. The latest commit completes the declaration-based contract for machine-late helpers. X86 and AArch64 stack-growth/write-barrier expansion locate the suffixed declaration already emitted by the Go compiler and use that exact symbol. LLVM therefore has no duplicate Go builtin table. Production Go IR fails closed when a required declaration is missing; `-linkshared` deliberately falls back to the canonical name, matching native Go's disabled builtin-index references. The dependent Go change is goallc/go#131. It joins the existing GoObj builtin list with the existing typed declarations generated by `mkbuiltin`; it does not add another builtin definition list. Validation: - focused X86/AArch64 stack-growth and write-barrier lit tests: 5/5 passed, including `-linkshared` fallback - broader Generic/X86/AArch64 Go and GoObj lit coverage: 60 passed, 1 unsupported; the only excluded failure is the pre-existing stale REP expectation in `go-memset-inline.ll` - Go compiler focused tests and 15 LLVM codegen fixtures passed with the dependent Go change - a full Go/LLVM joint `make.bash` completed on darwin/arm64 - runtime and its dependency closure compiled through LLVM, produced GoObj/archive output, and reached final link; the remaining failure is the independent `callRet` nosplit chain exceeding the 792-byte limit by 8 bytes
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## Summary - carry the runtime-specific LLVM lowering needed to compile the runtime package - encode ordinary GoObj builtin references as `<builtin.N>` LLVM declaration names, created lazily from each exact SSA/AuxCall signature - generate the late-machine-helper classification from `mkbuiltin.go` and eagerly retain only `gcWriteBarrier1..8` plus the three `morestack` ABI0 declarations - keep runtime implementations on their canonical names; ABI0 remains the outer `<ABI0>` suffix - remove the old `!goobj.builtin` reference metadata path and pin the merged LLVM #79 release This replaces the runtime-lowering and builtin portions of #131. The remaining linkname naming contract stays in #131; eager declarations for the full builtin table, provisional `any` signatures, and named-aggregate call-boundary reshaping are deliberately outside this PR. Depends on goallc/llvm-project#79 and release `goallc-llvm23.1.0-20260814T092516Z` (`3710742685729c697378ab13a456484e5693aba9`). ## Validation - `go test cmd/internal/goobj cmd/dist cmd/llvmtoolexec` - `go test -tags="llvm23 dynamicllvm" cmd/compile/internal/ssa` - all 130 LLVM codegen cases on darwin/arm64 - IR -> LLVM O2 -> GoObj -> link -> execute smoke test - LLVM O2/GoObj archive generation for runtime and its exact 28-package dependency closure - generated `builtinlist.go` matches `mkbuiltin.go -stdout` ## Known independent follow-ups - linking the fully LLVM-built runtime closure reaches the existing `callRet: nosplit stack over 792 byte limit` by 8 bytes - `runtime.test` additionally reaches the separate named-aggregate `pageCache` / `PageCache` caller-boundary issue
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This is 2/5 of the remaining runtime LLVM support stack. It depends on the pure linkname contract in #131; the runtime-lowering and builtin foundation is merged in #136. Stack: #136 (merged) -> #131 -> this PR -> #133 -> #134 -> #135. Keep named aggregate types in ABIInternal declarations and definitions. When a caller and callee describe the same physical Go ABI carrier with different nominal types, the caller rebuilds the value at the call boundary. This includes compiler-generated runtime calls, promoted method receivers, results, and open-defer result carriers. The callee signature is recovered from the current-package definition; the caller AuxCall remains authoritative for physical ABI assignment. The differential ABI tests run the normal O2 pipeline before checking fixed stack homes. Focused unit and codegen tests cover named runtime aggregates, caller-side carrier reshaping, promoted receivers, current-package callee signatures, defined aggregate conversions, and named open-defer results. Rebased validation: - joint `make.bash` with the LLVM #79 payload - `cmd/compile/internal/ssa` unit tests - LLVM ABI differential and `llvm_opendefer.go` codegen tests Supersedes the named-ABI and promoted-receiver portions of #128.
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This is the traceback/inline layer of the remaining runtime LLVM support. PR #132 is merged. Stack: #136 (merged) -> #131 (merged) -> #132 (merged) -> this PR -> #134 -> #135. Preserve runtime traceback and defer semantics across LLVM optimization: - record required frontend inline edges independently of surviving instructions - materialize machine-level inline anchors only when optimization removed an edge - attach the native function-end source position to the synthetic deferreturn recovery call - keep runtime.gorecover itself as a physical frame, while allowing its direct callers to be represented by Go inline frames - conservatively keep nosplit functions out of LLVM inlining so the runtime callRet chain stays within the linker-enforced final GoObj stack limit The nosplit fence is intentionally temporary: native Go permits nosplit inlining, and the linker checks the final PCSP tables and call relocations. The source now carries a TODO to replace the blanket fence with a targeted policy after the callRet frame growth is understood. The debug fixture uses the final machine layout after LLVM #78, including small-leaf stack-check elision. Validation after rebasing onto b79bf4b: - joint make.bash - full cmd/compile/internal/ssa tests with LLVM enabled - focused gorecover identity test - 90/90 plugin CTest, including X86 and AArch64 debug-inline GoObj checks - open-defer codegen through LLVM O2, checking the recover caller attribute group has no noinline - recover1.go passed three consecutive LLVM O2 runs - optimized IR confirms LLVM actually inlined direct recover callers and retained their inlinedAt locations; direct, nested, recursive, and no-op recover semantics still pass - runtime and its 28 dependencies through LLVM O2 with test dependencies native: runtime.test links successfully and the previous callRet nosplit overflow is gone Executing that runtime.test reaches a separate LLVM late stack-check issue before test enumeration: runtime.tlsinit.abi0 receives a stack-growth prologue although the native Go ABI0 wrapper does not. This is after successful linking and is not a symbol-resolution or inline-budget failure in this PR. Supersedes the traceback/defer portion of #128.
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This is the entry-argument-map and stack-growth layer of the remaining runtime LLVM support. PR #133 is merged. Stack: #136 (merged) -> #131 (merged) -> #132 (merged) -> #133 (merged) -> this PR -> #135. Implement the final entry-map and stack-growth contract agreed with LLVM #78: - every GoObj Go function keeps entry ArgsPointerMaps map 0 - entry and entry-depth PCDATA_StackMapIndex ranges use the native -1 sentinel - runtime stack-map lookup interprets that sentinel as entry map 0 - nosplit and systemstack are explicit function policies; the obsolete stack-growth statepoint attribute is removed - morestack remains a raw call, while LLVM decides from final frame size and leafness whether a split prologue is needed - GoObj derives entry map ranges from CFG state rather than a dedicated morestack marker The Machine StackMaps bridge remains Go-owned: `GoALLCStackMapPrinter` distinguishes the function-entry `STACKMAP` from ordinary statepoint records and passes their raw locations through `MCContext`; LLVM only provides generic metadata-printer dispatch and final GoObj serialization. Object-level `objview` checks cover entry PCDATA=-1, entry ArgsPointerMaps map 0, ordinary statepoint map 1, returning to entry depth, and the morestack map-0 path. The pinned payload is `goallc-llvm23.1.0-20260815T055258Z`, revision `ce1ede9c622755eeeb0ea695d5bffad3bac32dcc`, released after LLVM #81 merged. Validation after rebasing onto #133 merge `24581b9a69`: - coordinated Release+assertions X86/AArch64 LLVM build - 42 focused LLVM GoObj CodeGen tests - 91/91 plugin CTest with structured objview checks - prior joint `make.bash` and linux amd64/arm64 CI on the fallback payload - full `cmd/compile/internal/ssa` tests with LLVM enabled - ABI differential source and machine ArgsPointerMaps tests - caller-state and nosplit GoObj tests - statepoint codegen through LLVM O2 The stale LLVM `nowritebarrierrec` propagation test from the old stack was removed: finalized-IR enforcement remains the existing explicit TODO and is outside this entry-map PR. Supersedes the entry-argmap and stack-growth portion of #128.
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This is 1/5 of the remaining runtime LLVM support stack after the runtime-lowering and builtin foundation merged in #136.
Stack: #136 (merged) -> this PR -> #132 -> #133 -> #134 -> #135.
This layer completes the Go producer side of the name-only GoObj reference contract already consumed by merged LLVM #79:
<linkname>LLVM declaration suffixname+ABIdefinition set keeps local function and data pushes on canonical nameslinknameand standard-librarylinknamestdreferences are handled<ABI0>stays the outer ABI suffixlinknamestddata definitions retain the standard-library authorization flagThe Go IR, SSA, AuxCall, and LSym models are unchanged; no linkname metadata table is added. This PR also does not reintroduce eager full-table builtin declarations, provisional
anysignatures, closure provenance checks, a second cgo parameter-home mechanism, or named-aggregate ABI reshaping.Validation:
go test -tags="llvm23 dynamicllvm" cmd/internal/goobj cmd/compile/internal/ssanonpackage_referencewithlinkname; local ABIInternal and ABI0 definitions remain canonicalmake.bashand downstream focused testsSupersedes only the linkname portion of #128 and the previous mixed implementation in this PR.