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2024-07-07Zcu: introduce `PerThread` and pass to all the functionsJacob Young
2024-07-04Zcu: extract permanent state from FileAndrew Kelley
Primarily, this commit removes 2 fields from File, relying on the data being stored in the `files` field, with the key as the path digest, and the value as the struct decl corresponding to the File. This table is serialized into the compiler state that survives between incremental updates. Meanwhile, the File struct remains ephemeral data that can be reconstructed the first time it is needed by the compiler process, as well as operated on by independent worker threads. A key outcome of this commit is that there is now a stable index that can be used to refer to a File. This will be needed when serializing error messages to survive incremental compilation updates.
2024-07-04cbe: fix for export changesJacob Young
2024-07-04compiler: type.zig -> Type.zigmlugg
2024-07-04Zcu: store `LazySrcLoc` in error messagesmlugg
This change modifies `Zcu.ErrorMsg` to store a `Zcu.LazySrcLoc` rather than a `Zcu.SrcLoc`. Everything else is dominoes. The reason for this change is incremental compilation. If a failed `AnalUnit` is up-to-date on an update, we want to re-use the old error messages. However, the file containing the error location may have been modified, and `SrcLoc` cannot survive such a modification. `LazySrcLoc` is designed to be correct across incremental updates. Therefore, we defer source location resolution until `Compilation` gathers the compile errors into the `ErrorBundle`.
2024-07-04Zcu: rework exportsmlugg
This commit reworks our representation of exported Decls and values in Zcu to be memory-optimized and trivially serialized. All exports are now stored in the `all_exports` array on `Zcu`. An `AnalUnit` which performs an export (either through an `export` annotation or by containing an analyzed `@export`) gains an entry into `single_exports` if it performs only one export, or `multi_exports` if it performs multiple. We no longer store a persistent mapping from a `Decl`/value to all exports of that entity; this state is not necessary for the majority of the pipeline. Instead, we construct it in `Zcu.processExports`, just before flush. This does not affect the algorithmic complexity of `processExports`, since this function already iterates all exports in the `Zcu`. The elimination of `decl_exports` and `value_exports` led to a few non-trivial backend changes. The LLVM backend has been wrangled into a more reasonable state in general regarding exports and externs. The C backend is currently disabled in this commit, because its support for `export` was quite broken, and that was exposed by this work -- I'm hoping @jacobly0 will be able to pick this up!
2024-06-22rename src/Module.zig to src/Zcu.zigAndrew Kelley
This patch is a pure rename plus only changing the file path in `@import` sites, so it is expected to not create version control conflicts, even when rebasing.
2024-06-15Zcu: rework source locationsmlugg
`LazySrcLoc` now stores a reference to the "base AST node" to which it is relative. The previous tagged union is `LazySrcLoc.Offset`. To make working with this structure convenient, `Sema.Block` contains a convenience `src` method which takes an `Offset` and returns a `LazySrcLoc`. The "base node" of a source location is no longer given by a `Decl`, but rather a `TrackedInst` representing either a `declaration`, `struct_decl`, `union_decl`, `enum_decl`, or `opaque_decl`. This is a more appropriate model, and removes an unnecessary responsibility from `Decl` in preparation for the upcoming refactor which will split it into `Nav` and `Cau`. As a part of these `Decl` reworks, the `src_node` field is eliminated. This change aids incremental compilation, and simplifies `Decl`. In some cases -- particularly in backends -- the source location of a declaration is desired. This was previously `Decl.srcLoc` and worked for any `Decl`. Now, it is `Decl.navSrcLoc` in reference to the upcoming refactor, since the set of `Decl`s this works for precisely corresponds to what will in future become a `Nav` -- that is, source-level declarations and generic function instantiations, but *not* type owner Decls. This commit introduces more tags to `LazySrcLoc.Offset` so as to eliminate the concept of `error.NeededSourceLocation`. Now, `.unneeded` should only be used to assert that an error path is unreachable. In the future, uses of `.unneeded` can probably be replaced with `undefined`. The `src_decl` field of `Sema.Block` no longer has a role in type resolution. Its main remaining purpose is to handle namespacing of type names. It will be eliminated entirely in a future commit to remove another undue responsibility from `Decl`. It is worth noting that in future, the `Zcu.SrcLoc` type should probably be eliminated entirely in favour of storing `Zcu.LazySrcLoc` values. This is because `Zcu.SrcLoc` is not valid across incremental updates, and we want to be able to reuse error messages from previous updates even if the source file in question changed. The error reporting logic should instead simply resolve the location from the `LazySrcLoc` on the fly.
2024-06-15compiler: move LazySrcLoc out of stdmlugg
This is in preparation for some upcoming changes to how we represent source locations in the compiler. The bulk of the change here is dealing with the removal of `src()` methods from `Zir` types.
2024-05-22Revert "implement `@expect` builtin (#19658)"Andrew Kelley
This reverts commit a7de02e05216db9a04e438703ddf1b6b12f3fbef. This did not implement the accepted proposal, and I did not sign off on the changes. I would like a chance to review this, please.
2024-05-22implement `@expect` builtin (#19658)David Rubin
* implement `@expect` * add docs * add a second arg for expected bool * fix typo * move `expect` to use BinOp * update to newer langref format
2024-04-30cbe: fix ub with integer `@abs`Jacob Young
2024-04-30C backend: avoid memcpy when len=0Andrew Kelley
As of Clang 18, calling memcpy() with a misaligned pointer trips UBSAN, even if the length is zero. This unfortunately includes any call to `@memcpy` when source or destination are undefined and the length is zero. This patch makes the C backend avoid calling memcpy when the length is zero, thereby avoiding undefined behavior. A zig1.wasm update will be needed in the llvm18 branch to activate this code.
2024-04-22ComptimeStringMap: return a regular struct and optimizeTravis Staloch
this patch renames ComptimeStringMap to StaticStringMap, makes it accept only a single type parameter, and return a known struct type instead of an anonymous struct. initial motivation for these changes was to reduce the 'very long type names' issue described here https://github.com/ziglang/zig/pull/19682. this breaks the previous API. users will now need to write: `const map = std.StaticStringMap(T).initComptime(kvs_list);` * move `kvs_list` param from type param to an `initComptime()` param * new public methods * `keys()`, `values()` helpers * `init(allocator)`, `deinit(allocator)` for runtime data * `getLongestPrefix(str)`, `getLongestPrefixIndex(str)` - i'm not sure these belong but have left in for now incase they are deemed useful * performance notes: * i posted some benchmarking results here: https://github.com/travisstaloch/comptime-string-map-revised/issues/1 * i noticed a speedup reducing the size of the struct from 48 to 32 bytes and thus use u32s instead of usize for all length fields * i noticed speedup storing KVs as a struct of arrays * latest benchmark shows these wall_time improvements for debug/safe/small/fast builds: -6.6% / -10.2% / -19.1% / -8.9%. full output in link above.
2024-04-17compiler: rework comptime pointer representation and accessmlugg
We've got a big one here! This commit reworks how we represent pointers in the InternPool, and rewrites the logic for loading and storing from them at comptime. Firstly, the pointer representation. Previously, pointers were represented in a highly structured manner: pointers to fields, array elements, etc, were explicitly represented. This works well for simple cases, but is quite difficult to handle in the cases of unusual reinterpretations, pointer casts, offsets, etc. Therefore, pointers are now represented in a more "flat" manner. For types without well-defined layouts -- such as comptime-only types, automatic-layout aggregates, and so on -- we still use this "hierarchical" structure. However, for types with well-defined layouts, we use a byte offset associated with the pointer. This allows the comptime pointer access logic to deal with reinterpreted pointers far more gracefully, because the "base address" of a pointer -- for instance a `field` -- is a single value which pointer accesses cannot exceed since the parent has undefined layout. This strategy is also more useful to most backends -- see the updated logic in `codegen.zig` and `codegen/llvm.zig`. For backends which do prefer a chain of field and elements accesses for lowering pointer values, such as SPIR-V, there is a helpful function in `Value` which creates a strategy to derive a pointer value using ideally only field and element accesses. This is actually more correct than the previous logic, since it correctly handles pointer casts which, after the dust has settled, end up referring exactly to an aggregate field or array element. In terms of the pointer access code, it has been rewritten from the ground up. The old logic had become rather a mess of special cases being added whenever bugs were hit, and was still riddled with bugs. The new logic was written to handle the "difficult" cases correctly, the most notable of which is restructuring of a comptime-only array (for instance, converting a `[3][2]comptime_int` to a `[2][3]comptime_int`. Currently, the logic for loading and storing work somewhat differently, but a future change will likely improve the loading logic to bring it more in line with the store strategy. As far as I can tell, the rewrite has fixed all bugs exposed by #19414. As a part of this, the comptime bitcast logic has also been rewritten. Previously, bitcasts simply worked by serializing the entire value into an in-memory buffer, then deserializing it. This strategy has two key weaknesses: pointers, and undefined values. Representations of these values at comptime cannot be easily serialized/deserialized whilst preserving data, which means many bitcasts would become runtime-known if pointers were involved, or would turn `undefined` values into `0xAA`. The new logic works by "flattening" the datastructure to be cast into a sequence of bit-packed atomic values, and then "unflattening" it; using serialization when necessary, but with special handling for `undefined` values and for pointers which align in virtual memory. The resulting code is definitely slower -- more on this later -- but it is correct. The pointer access and bitcast logic required some helper functions and types which are not generally useful elsewhere, so I opted to split them into separate files `Sema/comptime_ptr_access.zig` and `Sema/bitcast.zig`, with simple re-exports in `Sema.zig` for their small public APIs. Whilst working on this branch, I caught various unrelated bugs with transitive Sema errors, and with the handling of `undefined` values. These bugs have been fixed, and corresponding behavior test added. In terms of performance, I do anticipate that this commit will regress performance somewhat, because the new pointer access and bitcast logic is necessarily more complex. I have not yet taken performance measurements, but will do shortly, and post the results in this PR. If the performance regression is severe, I will do work to to optimize the new logic before merge. Resolves: #19452 Resolves: #19460
2024-04-13cbe: fix optional codegenJacob Young
Also reduce ctype pool string memory usage, remove self assignments, and enable more warnings.
2024-04-08InternPool: remove slice from byte aggregate keysJacob Young
This deletes a ton of lookups and avoids many UAF bugs. Closes #19485
2024-04-08cbe: fix struct field location computationJacob Young
2024-04-08cbe: remove threadlocal variables in single threaded modeJacob Young
2024-04-06Builder: fix encoding big integers in bitcodeJacob Young
Closes #19543
2024-03-30cbe: fix uncovered bugsJacob Young
2024-03-30cbe: rewrite `CType`Jacob Young
Closes #14904
2024-03-30cbe: fix bugs revealed by an upcoming commitJacob Young
Closes #18023
2024-03-26compiler: eliminate most usages of TypedValuemlugg
2024-03-26Zcu: eliminate `Decl.alive` fieldmlugg
Legacy anon decls now have three uses: * Type owner decls * Function owner decls * `@export` and `@extern` Therefore, there are no longer any cases where we wish to explicitly omit legacy anon decls from the binary. This means we can remove the concept of an "alive" vs "dead" `Decl`, which also allows us to remove the separate `anon_work_queue` in `Compilation`.
2024-03-26compiler: eliminate legacy Value representationmlugg
Good riddance! Most of these changes are trivial. There's a fix for a minor bug this exposed in `Value.readFromPackedMemory`, but aside from that, it's all just things like changing `intern` calls to `toIntern`.
2024-03-26Zcu.Decl: remove `ty` fieldmlugg
`Decl` can no longer store un-interned values, so this field is now unnecessary. The type can instead be fetched with the new `typeOf` helper method, which just gets the type of the Decl's `Value`.
2024-03-25compiler: implement analysis-local comptime-mutable memorymlugg
This commit changes how we represent comptime-mutable memory (`comptime var`) in the compiler in order to implement the intended behavior that references to such memory can only exist at comptime. It does *not* clean up the representation of mutable values, improve the representation of comptime-known pointers, or fix the many bugs in the comptime pointer access code. These will be future enhancements. Comptime memory lives for the duration of a single Sema, and is not permitted to escape that one analysis, either by becoming runtime-known or by becoming comptime-known to other analyses. These restrictions mean that we can represent comptime allocations not via Decl, but with state local to Sema - specifically, the new `Sema.comptime_allocs` field. All comptime-mutable allocations, as well as any comptime-known const allocs containing references to such memory, live in here. This allows for relatively fast checking of whether a value references any comptime-mtuable memory, since we need only traverse values up to pointers: pointers to Decls can never reference comptime-mutable memory, and pointers into `Sema.comptime_allocs` always do. This change exposed some faulty pointer access logic in `Value.zig`. I've fixed the important cases, but there are some TODOs I've put in which are definitely possible to hit with sufficiently esoteric code. I plan to resolve these by auditing all direct accesses to pointers (most of them ought to use Sema to perform the pointer access!), but for now this is sufficient for all realistic code and to get tests passing. This change eliminates `Zcu.tmp_hack_arena`, instead using the Sema arena for comptime memory mutations, which is possible since comptime memory is now local to the current Sema. This change should allow `Decl` to store only an `InternPool.Index` rather than a full-blown `ty: Type, val: Value`. This commit does not perform this refactor.
2024-03-17cbe: rework StringLiteral to decide between string literal or array ↵kcbanner
initializator syntax This fixes an issue with boostrapping the compiler using MSVC. There is a CircularBuffer with an array of length 65536 initialized to undefined, and because the undefined path of `renderValue` was using `StringLiteral` to render this, the resulting zig2.c would fail to compile using MSVC. The solution was to move the already-existing array initializer path (used in the non-undefined path) into StringLiteral, and make StringLiteral aware of the total length so it could decide between which style of initialization to use. We prefer to use string literals if we can, as this results in the least amount of emitted C source.
2024-03-17AstGen: disallow alignment on function typesJacob Young
A pointer type already has an alignment, so this information does not need to be duplicated on the function type. This already has precedence with addrspace which is already disallowed on function types for this reason. Also fixes `@TypeOf(&func)` to have the correct addrspace and alignment.
2024-03-11std.builtin: make atomic order fields lowercaseTristan Ross
2024-03-11std.builtin: make global linkage fields lowercaseTristan Ross
2024-03-11std.builtin: make container layout fields lowercaseTristan Ross
2024-03-06Fix incorrectly resolved merge conflictsmlugg
To be honest, I can't be bothered to figure out which commits these changes should be in.
2024-03-06InternPool: create specialized functions for loading namespace typesmlugg
Namespace types (`struct`, `enum`, `union`, `opaque`) do not use structural equality - equivalence is based on their Decl index (and soon will change to AST node + captures). However, we previously stored all other information in the corresponding `InternPool.Key` anyway. For logical consistency, it makes sense to have the key only be the true key (that is, the Decl index) and to load all other data through another function. This introduces those functions, by the name of `loadStructType` etc. It's a big diff, but most of it is no-brainer changes. In future, it might be nice to eliminate a bunch of the loaded state in favour of accessor functions on the `LoadedXyzType` types (like how we have `LoadedUnionType.size()`), but that can be explored at a later date.
2024-03-02Air: replace `.dbg_inline_*` with `.dbg_inline_block`Jacob Young
This prevents the possibility of not emitting a `.dbg_inline_end` instruction and reduces the allocation requirements of the backends. Closes #19093
2024-02-26move Zcu.LazySrcLoc to std.zig.LazySrcLocAndrew Kelley
Part of an effort to ship more of the compiler in source form.
2024-02-26compiler: decide dbg_var scoping based on AIR blocksmlugg
This commit eliminates the `dbg_block_{begin,end}` instructions from both ZIR and AIR. Instead, lexical scoping of `dbg_var_{ptr,val}` instructions is decided based on the AIR block they exist within. This is a much more robust system, and also results in a huge drop in ZIR bytes - around 7% for Sema.zig. This required some enhancements to Sema to prevent elision of blocks when they are required for debug variable scoping. This can be observed by looking at the AIR for the following simple test program with and without `-fstrip`: ```zig export fn f() void { { var a: u32 = 0; _ = &a; } { var a: u32 = 0; _ = &a; } } ``` When `-fstrip` is passed, no AIR blocks are generated. When `-fno-strip` is passed, the ZIR blocks are lowered to true AIR blocks to give correct lexical scoping to the debug vars. The changes here incidentally reolve #19060. A corresponding behavior test has been added. Resolves: #19060
2024-02-25x86_64: implement optional comparisonsJacob Young
Closes #18959
2024-02-25Sema: implement vector coercionsJacob Young
These used to be lowered elementwise in air, and now are a single air instruction that can be lowered elementwise in the backend if necessary.
2024-02-19cbe: make more use of `InternPool.Index.Slice`Jacob Young
Attempts to fix the current CI failures introduced by #18983.
2024-02-16InternPool: make more use of `NullTerminatedString.Slice`Jacob Young
This should avoid the random pointer invalidation crashes. Closes #18954
2024-02-07Merge pull request #17634 from ianprime0509/type-erased-writerAndrew Kelley
Add type-erased writer and GenericWriter
2024-02-05compiler: rename value.zig to Value.zigAndrew Kelley
This commit only does the file rename to be friendlier to version control conflicts.
2024-02-02InternPool: use separate key for slicesmlugg
This change eliminates some problematic recursive logic in InternPool, and provides a safer API.
2024-01-29llvm: ensure returned undef is 0xaa bytes when runtime safety is enabledVeikka Tuominen
Closes #13178
2024-01-29Introduce type-erased writers to C backend codegenIan Johnson
This reduces generic instantiations of several write functions. Before: ``` @as(type, io.writer.Writer(*array_list.ArrayListAligned(u8,null),error{OutOfMemory},(function 'appendWrite'))) @as(type, io.writer.Writer(*codegen.c.IndentWriter(io.writer.Writer(*array_list.ArrayListAligned(u8,null),error{OutOfMemory},(function 'appendWrite'))),error{OutOfMemory},(function 'write'))) ``` After: ``` @as(type, io.GenericWriter(io.Writer,error{OutOfMemory},(function 'write'))) ```
2024-01-03cbe: fix non-msvc externs and exportsJacob Young
Closes #17817
2024-01-03Reapply "Merge pull request #17824 from kcbanner/fixup_msvc_fmax"Jacob Young
This reverts commit 2b589783602c5428ecde9dbb3f41a81f85eb0f25.
2024-01-01Revert "Merge pull request #17824 from kcbanner/fixup_msvc_fmax"Andrew Kelley
This reverts commit 7161ed79c4abcaccdd56fe0b4fbd3d93472d41b8, reversing changes made to 3f2a65594e1d3c0a4f4943a4ea522e8405db81e0. Unfortunately, this sat in the PR queue too long and the merge broke the zig1.wasm bootstrap process.