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2025-02-22zig build fmtAndrew Kelley
2025-02-17std.builtin: Remove CallingConvention.arm_(apcs,aapcs16_vfp).Alex Rønne Petersen
* arm_apcs is the long dead "OABI" which we never had working support for. * arm_aapcs16_vfp is for arm-watchos-none which is a dead target that we've dropped support for.
2025-02-10cbe: fix crash rendering argument names in lazy functionsJacob Young
Closes #19905
2025-02-10cbe: emit linksection for `@export`Jacob Young
Closes #21490
2025-02-07std.ArrayHashMap: popOrNul() -> pop()Meghan Denny
2025-01-31Sema: introduce all_vector_instructions backend featureJacob Young
Sema is arbitrarily scalarizing some operations, which means that when I try to implement vectorized versions of those operations in a backend, they are impossible to test due to Sema not producing them. Now, I can implement them and then temporarily enable the new feature for that backend in order to test them. Once the backend supports all of them, the feature can be permanently enabled. This also deletes the Air instructions `int_from_bool` and `int_from_ptr`, which are just bitcasts with a fixed result type, since changing `un_op` to `ty_op` takes up the same amount of memory.
2025-01-30compiler: add `intcast_safe` AIR instructionmlugg
This instruction is like `intcast`, but includes two safety checks: * Checks that the int is in range of the destination type * If the destination type is an exhaustive enum, checks that the int is a named enum value This instruction is locked behind the `safety_checked_instructions` backend feature; if unsupported, Sema will emit a fallback, as with other safety-checked instructions. This instruction is used to add a missing safety check for `@enumFromInt` truncating bits. This check also has a fallback for backends which do not yet support `safety_checked_instructions`. Resolves: #21946
2025-01-24x86_64: rewrite float vector `@abs` and equality comparisonsJacob Young
2025-01-21compiler: simplify generic functions, fix issues with inline callsmlugg
The original motivation here was to fix regressions caused by #22414. However, while working on this, I ended up discussing a language simplification with Andrew, which changes things a little from how they worked before #22414. The main user-facing change here is that any reference to a prior function parameter, even if potentially comptime-known at the usage site or even not analyzed, now makes a function generic. This applies even if the parameter being referenced is not a `comptime` parameter, since it could still be populated when performing an inline call. This is a breaking language change. The detection of this is done in AstGen; when evaluating a parameter type or return type, we track whether it referenced any prior parameter, and if so, we mark this type as being "generic" in ZIR. This will cause Sema to not evaluate it until the time of instantiation or inline call. A lovely consequence of this from an implementation perspective is that it eliminates the need for most of the "generic poison" system. In particular, `error.GenericPoison` is now completely unnecessary, because we identify generic expressions earlier in the pipeline; this simplifies the compiler and avoids redundant work. This also entirely eliminates the concept of the "generic poison value". The only remnant of this system is the "generic poison type" (`Type.generic_poison` and `InternPool.Index.generic_poison_type`). This type is used in two places: * During semantic analysis, to represent an unknown result type. * When storing generic function types, to represent a generic parameter/return type. It's possible that these use cases should instead use `.none`, but I leave that investigation to a future adventurer. One last thing. Prior to #22414, inline calls were a little inefficient, because they re-evaluated even non-generic parameter types whenever they were called. Changing this behavior is what ultimately led to #22538. Well, because the new logic will mark a type expression as generic if there is any change its resolved type could differ in an inline call, this redundant work is unnecessary! So, this is another way in which the new design reduces redundant work and complexity. Resolves: #22494 Resolves: #22532 Resolves: #22538
2025-01-16all: update to `std.builtin.Type.Pointer.Size` field renamesmlugg
This was done by regex substitution with `sed`. I then manually went over the entire diff and fixed any incorrect changes. This diff also changes a lot of `callconv(.C)` to `callconv(.c)`, since my regex happened to also trigger here. I opted to leave these changes in, since they *are* a correct migration, even if they're not the one I was trying to do!
2025-01-15compiler: add type safety for export indicesAndrew Kelley
2025-01-10cbe: fix miscomps of the compilerJacob Young
2025-01-08cbe: fix miscomps of x86_64 backendJacob Young
2024-12-24compiler: analyze type and value of global declaration separatelymlugg
This commit separates semantic analysis of the annotated type vs value of a global declaration, therefore allowing recursive and mutually recursive values to be declared. Every `Nav` which undergoes analysis now has *two* corresponding `AnalUnit`s: `.{ .nav_val = n }` and `.{ .nav_ty = n }`. The `nav_val` unit is responsible for *fully resolving* the `Nav`: determining its value, linksection, addrspace, etc. The `nav_ty` unit, on the other hand, resolves only the information necessary to construct a *pointer* to the `Nav`: its type, addrspace, etc. (It does also analyze its linksection, but that could be moved to `nav_val` I think; it doesn't make any difference). Analyzing a `nav_ty` for a declaration with no type annotation will just mark a dependency on the `nav_val`, analyze it, and finish. Conversely, analyzing a `nav_val` for a declaration *with* a type annotation will first mark a dependency on the `nav_ty` and analyze it, using this as the result type when evaluating the value body. The `nav_val` and `nav_ty` units always have references to one another: so, if a `Nav`'s type is referenced, its value implicitly is too, and vice versa. However, these dependencies are trivial, so, to save memory, are only known implicitly by logic in `resolveReferences`. In general, analyzing ZIR `decl_val` will only analyze `nav_ty` of the corresponding `Nav`. There are two exceptions to this. If the declaration is an `extern` declaration, then we immediately ensure the `Nav` value is resolved (which doesn't actually require any more analysis, since such a declaration has no value body anyway). Additionally, if the resolved type has type tag `.@"fn"`, we again immediately resolve the `Nav` value. The latter restriction is in place for two reasons: * Functions are special, in that their externs are allowed to trivially alias; i.e. with a declaration `extern fn foo(...)`, you can write `const bar = foo;`. This is not allowed for non-function externs, and it means that function types are the only place where it is possible for a declaration `Nav` to have a `.@"extern"` value without actually being declared `extern`. We need to identify this situation immediately so that the `decl_ref` can create a pointer to the *real* extern `Nav`, not this alias. * In certain situations, such as taking a pointer to a `Nav`, Sema needs to queue analysis of a runtime function if the value is a function. To do this, the function value needs to be known, so we need to resolve the value immediately upon `&foo` where `foo` is a function. This restriction is simple to codify into the eventual language specification, and doesn't limit the utility of this feature in practice. A consequence of this commit is that codegen and linking logic needs to be more careful when looking at `Nav`s. In general: * When `updateNav` or `updateFunc` is called, it is safe to assume that the `Nav` being updated (the owner `Nav` for `updateFunc`) is fully resolved. * Any `Nav` whose value is/will be an `@"extern"` or a function is fully resolved; see `Nav.getExtern` for a helper for a common case here. * Any other `Nav` may only have its type resolved. This didn't seem to be too tricky to satisfy in any of the existing codegen/linker backends. Resolves: #131
2024-12-08cbe: prevent tautological-compare warnings in generated codeJacob Young
2024-11-24dwarf: fix stepping through an inline loop containing one statementJacob Young
Previously, stepping from the single statement within the loop would always exit the loop because all of the code unrolled from the loop is associated with the same line and treated by the debugger as one line.
2024-11-03Merge pull request #21843 from alexrp/callconv-followupAlex Rønne Petersen
Some follow-up work for #21697
2024-11-03std.Target: Replace isARM() with isArmOrThumb() and rename it to isArm().Alex Rønne Petersen
The old isARM() function was a portability trap. With the name it had, it seemed like the obviously correct function to use, but it didn't include Thumb. In the vast majority of cases where someone wants to ask "is the target Arm?", Thumb *should* be included. There are exactly 3 cases in the codebase where we do actually need to exclude Thumb, although one of those is in Aro and mirrors a check in Clang that is itself likely a bug. These rare cases can just add an extra isThumb() check.
2024-11-02cbe: Support some more calling conventions.Alex Rønne Petersen
2024-11-02compiler: Handle arm_aapcs16_vfp alongside arm_aapcs_vfp in some places.Alex Rønne Petersen
2024-10-31compiler: remove anonymous struct types, unify all tuplesmlugg
This commit reworks how anonymous struct literals and tuples work. Previously, an untyped anonymous struct literal (e.g. `const x = .{ .a = 123 }`) was given an "anonymous struct type", which is a special kind of struct which coerces using structural equivalence. This mechanism was a holdover from before we used RLS / result types as the primary mechanism of type inference. This commit changes the language so that the type assigned here is a "normal" struct type. It uses a form of equivalence based on the AST node and the type's structure, much like a reified (`@Type`) type. Additionally, tuples have been simplified. The distinction between "simple" and "complex" tuple types is eliminated. All tuples, even those explicitly declared using `struct { ... }` syntax, use structural equivalence, and do not undergo staged type resolution. Tuples are very restricted: they cannot have non-`auto` layouts, cannot have aligned fields, and cannot have default values with the exception of `comptime` fields. Tuples currently do not have optimized layout, but this can be changed in the future. This change simplifies the language, and fixes some problematic coercions through pointers which led to unintuitive behavior. Resolves: #16865
2024-10-19cbe,translate-c: support more callconvsmlugg
There are several more that we could support here, but I didn't feel like going down the rabbit-hole of figuring them out. In particular, some of the Clang enum fields aren't specific enough for us, so we'll have to switch on the target to figure out how to translate-c them. That can be a future enhancement.
2024-10-19std.Target: rename `defaultCCallingConvention` and `Cpu.Arch.fromCallconv`mlugg
2024-10-19std: update for new `CallingConvention`mlugg
The old `CallingConvention` type is replaced with the new `NewCallingConvention`. References to `NewCallingConvention` in the compiler are updated accordingly. In addition, a few parts of the standard library are updated to use the new type correctly.
2024-10-19compiler: introduce new `CallingConvention`mlugg
This commit begins implementing accepted proposal #21209 by making `std.builtin.CallingConvention` a tagged union. The stage1 dance here is a little convoluted. This commit introduces the new type as `NewCallingConvention`, keeping the old `CallingConvention` around. The compiler uses `std.builtin.NewCallingConvention` exclusively, but when fetching the type from `std` when running the compiler (e.g. with `getBuiltinType`), the name `CallingConvention` is used. This allows a prior build of Zig to be used to build this commit. The next commit will update `zig1.wasm`, and then the compiler and standard library can be updated to completely replace `CallingConvention` with `NewCallingConvention`. The second half of #21209 is to remove `@setAlignStack`, which will be implemented in another commit after updating `zig1.wasm`.
2024-10-04remove `@fence` (#21585)David Rubin
closes #11650
2024-09-12Replace deprecated default initializations with decl literalsLinus Groh
2024-09-01cbe: don't emit 'x = x' in switch dispatch loopmlugg
2024-09-01compiler: implement labeled switch/continuemlugg
2024-09-01Air: add explicit `repeat` instruction to repeat loopsmlugg
This commit introduces a new AIR instruction, `repeat`, which causes control flow to move back to the start of a given AIR loop. `loop` instructions will no longer automatically perform this operation after control flow reaches the end of the body. The motivation for making this change now was really just consistency with the upcoming implementation of #8220: it wouldn't make sense to have this feature work significantly differently. However, there were already some TODOs kicking around which wanted this feature. It's useful for two key reasons: * It allows loops over AIR instruction bodies to loop precisely until they reach a `noreturn` instruction. This allows for tail calling a few things, and avoiding a range check on each iteration of a hot path, plus gives a nice assertion that validates AIR structure a little. This is a very minor benefit, which this commit does apply to the LLVM and C backends. * It should allow for more compact ZIR and AIR to be emitted by having AstGen emit `repeat` instructions more often rather than having `continue` statements `break` to a `block` which is *followed* by a `repeat`. This is done in status quo because `repeat` instructions only ever cause the direct parent block to repeat. Now that AIR is more flexible, this flexibility can be pretty trivially extended to ZIR, and we can then emit better ZIR. This commit does not implement this. Support for this feature is currently regressed on all self-hosted native backends, including x86_64. This support will be added where necessary before this branch is merged.
2024-09-01Air: direct representation of ranges in switch casesmlugg
This commit modifies the representation of the AIR `switch_br` instruction to represent ranges in cases. Previously, Sema emitted different AIR in the case of a range, where the `else` branch of the `switch_br` contained a simple `cond_br` for each such case which did a simple range check (`x > a and x < b`). Not only does this add complexity to Sema, which we would like to minimize, but it also gets in the way of the implementation of #8220. That proposal turns certain `switch` statements into a looping construct, and for optimization purposes, we want to lower this to AIR fairly directly (i.e. without involving a `loop` instruction). That means we would ideally like a single instruction to represent the entire `switch` statement, so that we can dispatch back to it with a different operand as in #8220. This is not really possible to do correctly under the status quo system. This commit implements lowering of this new `switch_br` usage in the LLVM and C backends. The C backend just turns any case containing ranges entirely into conditionals, as before. The LLVM backend is a little smarter, and puts scalar items into the `switch` instruction, only using conditionals for the range cases (which direct to the same bb). All remaining self-hosted backends are temporarily regressed in the presence of switch range cases. This functionality will be restored for at least the x86_64 backend before merge.
2024-08-28std: update `std.builtin.Type` fields to follow naming conventionsmlugg
The compiler actually doesn't need any functional changes for this: Sema does reification based on the tag indices of `std.builtin.Type` already! So, no zig1.wasm update is necessary. This change is necessary to disallow name clashes between fields and decls on a type, which is a prerequisite of #9938.
2024-08-27compiler,lib,test,langref: migrate `@setCold` to `@branchHint`mlugg
2024-08-27compiler: implement `@branchHint`, replacing `@setCold`mlugg
Implements the accepted proposal to introduce `@branchHint`. This builtin is permitted as the first statement of a block if that block is the direct body of any of the following: * a function (*not* a `test`) * either branch of an `if` * the RHS of a `catch` or `orelse` * a `switch` prong * an `or` or `and` expression It lowers to the ZIR instruction `extended(branch_hint(...))`. When Sema encounters this instruction, it sets `sema.branch_hint` appropriately, and `zirCondBr` etc are expected to reset this value as necessary. The state is on `Sema` rather than `Block` to make it automatically propagate up non-conditional blocks without special handling. If `@panic` is reached, the branch hint is set to `.cold` if none was already set; similarly, error branches get a hint of `.unlikely` if no hint is explicitly provided. If a condition is comptime-known, `cold` hints from the taken branch are allowed to propagate up, but other hints are discarded. This is because a `likely`/`unlikely` hint just indicates the direction this branch is likely to go, which is redundant information when the branch is known at comptime; but `cold` hints indicate that control flow is unlikely to ever reach this branch, meaning if the branch is always taken from its parent, then the parent is also unlikely to ever be reached. This branch information is stored in AIR `cond_br` and `switch_br`. In addition, `try` and `try_ptr` instructions have variants `try_cold` and `try_ptr_cold` which indicate that the error case is cold (rather than just unlikely); this is reachable through e.g. `errdefer unreachable` or `errdefer @panic("")`. A new API `unwrapSwitch` is introduced to `Air` to make it more convenient to access `switch_br` instructions. In time, I plan to update all AIR instructions to be accessed via an `unwrap` method which returns a convenient tagged union a la `InternPool.indexToKey`. The LLVM backend lowers branch hints for conditional branches and switches as follows: * If any branch is marked `unpredictable`, the instruction is marked `!unpredictable`. * Any branch which is marked as `cold` gets a `llvm.assume(i1 true) [ "cold"() ]` call to mark the code path cold. * If any branch is marked `likely` or `unlikely`, branch weight metadata is attached with `!prof`. Likely branches get a weight of 2000, and unlikely branches a weight of 1. In `switch` statements, un-annotated branches get a weight of 1000 as a "middle ground" hint, since there could be likely *and* unlikely *and* un-annotated branches. For functions, a `cold` hint corresponds to the `cold` function attribute, and other hints are currently ignored -- as far as I can tell LLVM doesn't really have a way to lower them. (Ideally, we would want the branch hint given in the function to propagate to call sites.) The compiler and standard library do not yet use this new builtin. Resolves: #21148
2024-08-25sema: clean-up `{union,struct}FieldAlignment` and friendsDavid Rubin
My main gripes with this design were that it was incorrectly namespaced, the naming was inconsistent and a bit wrong (`fooAlign` vs `fooAlignment`). This commit moves all the logic from `PerThread.zig` to use the zcu + tid system that the previous couple commits introduce. I've organized and merged the functions to be a bit more specific to their own purpose. - `fieldAlignment` takes a struct or union type, an index, and a Zcu (or the Sema version which takes a Pt), and gives you the alignment of the field at the index. - `structFieldAlignment` takes the field type itself, and provides the logic to handle special cases, such as externs. A design goal I had in mind was to avoid using the word 'struct' in the function name, when it worked for things that aren't structs, such as unions.
2024-08-25sema: rework type resolution to use Zcu when possibleDavid Rubin
2024-08-20Dwarf: emit info about inline call sitesJacob Young
2024-08-17frontend: incremental progressmlugg
This commit makes more progress towards incremental compilation, fixing some crashes in the frontend. Notably, it fixes the regressions introduced by #20964. It also cleans up the "outdated file root" mechanism, by virtue of deleting it: we now detect outdated file roots just after updating ZIR refs, and re-scan their namespaces.
2024-08-11compiler: split Decl into Nav and Caumlugg
The type `Zcu.Decl` in the compiler is problematic: over time it has gained many responsibilities. Every source declaration, container type, generic instantiation, and `@extern` has a `Decl`. The functions of these `Decl`s are in some cases entirely disjoint. After careful analysis, I determined that the two main responsibilities of `Decl` are as follows: * A `Decl` acts as the "subject" of semantic analysis at comptime. A single unit of analysis is either a runtime function body, or a `Decl`. It registers incremental dependencies, tracks analysis errors, etc. * A `Decl` acts as a "global variable": a pointer to it is consistent, and it may be lowered to a specific symbol by the codegen backend. This commit eliminates `Decl` and introduces new types to model these responsibilities: `Cau` (Comptime Analysis Unit) and `Nav` (Named Addressable Value). Every source declaration, and every container type requiring resolution (so *not* including `opaque`), has a `Cau`. For a source declaration, this `Cau` performs the resolution of its value. (When #131 is implemented, it is unsolved whether type and value resolution will share a `Cau` or have two distinct `Cau`s.) For a type, this `Cau` is the context in which type resolution occurs. Every non-`comptime` source declaration, every generic instantiation, and every distinct `extern` has a `Nav`. These are sent to codegen/link: the backends by definition do not care about `Cau`s. This commit has some minor technically-breaking changes surrounding `usingnamespace`. I don't think they'll impact anyone, since the changes are fixes around semantics which were previously inconsistent (the behavior changed depending on hashmap iteration order!). Aside from that, this changeset has no significant user-facing changes. Instead, it is an internal refactor which makes it easier to correctly model the responsibilities of different objects, particularly regarding incremental compilation. The performance impact should be negligible, but I will take measurements before merging this work into `master`. Co-authored-by: Jacob Young <jacobly0@users.noreply.github.com> Co-authored-by: Jakub Konka <kubkon@jakubkonka.com>
2024-07-20Fix typos in code comments in `src/`sobolevn
2024-07-13InternPool: add and use a mutate mutex for each listJacob Young
This allows the mutate mutex to only be locked during actual grows, which are rare. For the lists that didn't previously have a mutex, this change has little effect since grows are rare and there is zero contention on a mutex that is only ever locked by one thread. This change allows `extra` to be mutated without racing with a grow.
2024-07-10InternPool: make `global_error_set` thread-safeJacob Young
2024-07-10Zcu: cache fully qualified name on DeclJacob Young
This avoids needing to mutate the intern pool from backends.
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.