Draft
Conversation
Pure file move. allocconfig.h contains only compile-time constants with dependencies only on bits.h and mitigations.h (both in ds_core/). Moving it enables sizeclassstatic.h (next step) to live in ds_core/ without pulling in ds/. Changes: - git mv ds/allocconfig.h -> ds_core/allocconfig.h - Add #include bits.h and mitigations.h to moved file - Update include paths in ds/ds.h, ds/mpmcstack.h - Add allocconfig.h to ds_core/ds_core.h umbrella
Create ds_core/sizeclassstatic.h with compile-time sizeclass functions extracted from mem/sizeclasstable.h: - smallsizeclass_t (size_t typedef) - size_to_sizeclass_const() - NUM_SMALL_SIZECLASSES - sizeclass_to_size_const() - is_small_sizeclass() Move sizeclasstable.h from mem/ to ds/ (depends on PAL, not allocator). Remove redundant sizeclasstable.h includes from mem/ files.
Convert smallsizeclass_t from a size_t typedef to a struct with: - Explicit construction from size_t (no implicit conversion FROM) - Implicit conversion to size_t (for array indexing, comparisons) - Pre/post increment operators Provides type safety: alloc(size_t) (byte size) cannot be confused with alloc(smallsizeclass_t) (sizeclass index). Update all iteration sites to use explicit construction.
Add alloc(smallsizeclass_t) overload to corealloc and globalalloc that skips the dynamic sizeclass lookup. Refactor small_alloc to accept (smallsizeclass_t, size_t) and keep the single-arg (size_t) version as a forwarding overload. Update alloc<size>() to use compile-time sizeclass when the size is a known small sizeclass. Add libc::malloc_small(smallsizeclass_t) and libc::malloc_small_zero(smallsizeclass_t) as non-template entry points.
These are general-purpose data structures, not allocator-specific. Moving them reduces the dependency surface of mem/.
Mark dealloc(), debug_teardown(), and all libc namespace functions with SNMALLOC_USED_FUNCTION so they emit linkable symbols when compiled into a static library. No behavioural change.
Add __malloc_start_pointer() and __malloc_last_byte_pointer() to libc.h, alongside the existing __malloc_end_pointer(). These provide the external_pointer functionality through the libc API surface.
Add snmalloc_testlib.h (thin header with API declarations) and snmalloc_testlib.cc (single TU compiling full allocator + wrappers). CMake: build_test_library() creates a static library per flavour. All test executables link against it (ODR-safe). No tests converted yet — this just adds the infrastructure.
Convert simple alloc/dealloc tests to use snmalloc_testlib.h instead of snmalloc.h: - func/first_operation - func/teardown - func/multi_atexit - func/multi_threadatexit Replace MAX_SMALL_SIZECLASS_BITS with max_small_sizeclass_bits(). Replace alloc<Zero> with alloc<ZeroMem::YesZero>. Add pal/pal.h include to testlib header for report_fatal_error.
Convert perf tests that use only the public API: - perf/startup - perf/contention - perf/large_alloc - perf/low_memory Replace DefaultPal::tick() with pal_tick(), Aal::pause() with pal_pause().
Convert tests that use only the public API to snmalloc_testlib.h: - func/bits, func/memory, func/memory_usage, func/pool - func/protect_fork, func/redblack, func/statistics - perf/external_pointer, perf/lotsofthreads, perf/post_teardown - perf/singlethread Replace DefaultPal/Aal calls with pal_*() wrappers. Replace external_pointer<> with libc __malloc_*_pointer(). Replace alloc<Zero/Uninit> with alloc<ZeroMem::YesZero/NoZero>. Fix include order in ds/ds.h for pool.h/pooled.h dependencies.
Convert tests that need allocator internals (sizeclasses, pagemap, etc.) to use snmalloc_core.h alongside snmalloc_testlib.h: - func/malloc (replace our_* with testlib_* prefix) - func/pagemap - func/release-rounding - func/sizeclass
Move report_fatal_error() and message() template definitions from pal/pal.h into ds_core/helpers.h. They now call error() and message_impl() which are forward-declared non-template functions in ds_core/defines.h, with implementations in pal/pal.h that delegate to DefaultPal. This breaks the dependency of ds_core/ code on pal/: any code that includes ds_core/helpers.h can call report_fatal_error() without needing PAL headers. The linker resolves error() and message_impl() from the translation unit that includes pal.h. Update testlib.h to include pal/pal_consts.h instead of pal/pal.h. Fix memory.cc to use ds_aal/ds_aal.h for address_cast. Fix protect_fork.cc to include ds_aal/prevent_fork.h explicitly. Revert low-memory.cc to snmalloc.h (needs PalNotificationObject).
The header doesn't use errno itself. Tests that need it can include it directly.
Replace snmalloc_testlib.h with ds_core/helpers.h + ds_aal/prevent_fork.h. This test only uses PreventFork and message(), no allocator API.
These tests had indented #include directives under #ifdef RUN_TEST, which the earlier sed-based conversion missed. Convert them now.
Create ds_core/sizeclassconfig.h with the mitigation-independent sizeclass constants (INTERMEDIATE_BITS, MIN_ALLOC_STEP_SIZE, etc.). This file depends only on bits.h — no mitigations.h. Update sizeclassstatic.h to include sizeclassconfig.h instead of allocconfig.h. allocconfig.h now includes sizeclassconfig.h and keeps only the mitigation-dependent constants (MIN_OBJECT_COUNT, DEALLOC_BATCH_*, MAX_SLAB_SPAN_*, etc.). This makes the testlib header chain fully mitigation-independent: testlib.h -> sizeclassstatic.h -> sizeclassconfig.h -> bits.h
Move mitigations.h, allocconfig.h, and cheri.h from ds_core/ to a new mitigations/ directory. These files depend on SNMALLOC_CHECK_CLIENT compile-time flags and don't belong in ds_core/ (which should be mitigation-independent). New include hierarchy: ds_core/ → aal/ → ds_aal/ → mitigations/ → pal/ → ds/ → mem/ ds_core/ is now fully mitigation-independent. The testlib header (which includes only ds_core/ headers) produces identical output regardless of SNMALLOC_CHECK_CLIENT, enabling tests to be compiled once and linked against both fast and check testlib variants.
Tests that only include snmalloc_testlib.h are mitigation-independent: their compiled output is identical regardless of SNMALLOC_CHECK_CLIENT. Compile these into a shared OBJECT library and link against both the fast and check testlib variants, saving 15 redundant compilations. Build targets: 171 (down from 186). Test count unchanged: 56 func.
Collaborator
|
We can also try modules if speed is a concern. |
Member
Author
Mostly there is a lot of redundant work in the build, and I wanted to experiment with improving that. |
Use early return instead of nested if to make MSVC's flow analysis see that 'last' is always initialized before use in restore().
The testlib static library was missing -fsanitize and SNMALLOC_THREAD_SANITIZER_ENABLED when sanitizers are enabled, causing TSan false positives in tests linked against it.
MSVC ARM64EC generates exit-thunks that require strong definitions of called functions, not just address-taken references. Replace the volatile pointer array with a cold function that calls through to dealloc/debug_teardown, ensuring the compiler emits full definitions of these inline functions in the testlib TU.
The previous fix replaced address-taking with call-through, which broke x64 MSVC (address-taking was needed for COMDAT emission). ARM64EC needs call-through for exit-thunk generation. Do both.
The new mitigations/ directory was missing from the install(DIRECTORY) rules, causing vcpkg consumers to fail with missing header.
Same exit-thunk issue as dealloc/debug_teardown: ARM64EC needs call-through in addition to address-taking for all inline functions that tests may call across the testlib boundary.
…spec(noinline) Instead of complex per-function workarounds for ARM64EC exit-thunks, make SNMALLOC_USED_FUNCTION actually work on MSVC by defining it as __declspec(noinline). This prevents the compiler from inlining the functions away, ensuring standalone definitions exist in the testlib archive for the linker to resolve. Remove the #ifdef _MSC_VER block with duplicated function bodies and the _force_emit_calls/_force_emit_libc_calls call-through helpers. Keep the address-taking arrays as belt-and-suspenders.
Revert SNMALLOC_USED_FUNCTION change (caused C4141 warning conflict with SNMALLOC_FAST_PATH_INLINE). Instead, use NOINLINE wrapper functions inside testlib.cc under #ifdef _MSC_VER. Each wrapper calls the corresponding inline function, forcing MSVC to emit a standalone definition that ARM64EC exit-thunks can reference. GCC/Clang path unchanged (uses __attribute__((used)) via address-taking).
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
No description provided.