This commit replaces the "fuzzer" UI, previously accessed with the
`--fuzz` and `--port` flags, with a more interesting web UI which allows
more interactions with the Zig build system. Most notably, it allows
accessing the data emitted by a new "time report" system, which allows
users to see which parts of Zig programs take the longest to compile.
The option to expose the web UI is `--webui`. By default, it will listen
on `[::1]` on a random port, but any IPv6 or IPv4 address can be
specified with e.g. `--webui=[::1]:8000` or `--webui=127.0.0.1:8000`.
The options `--fuzz` and `--time-report` both imply `--webui` if not
given. Currently, `--webui` is incompatible with `--watch`; specifying
both will cause `zig build` to exit with a fatal error.
When the web UI is enabled, the build runner spawns the web server as
soon as the configure phase completes. The frontend code consists of one
HTML file, one JavaScript file, two CSS files, and a few Zig source
files which are built into a WASM blob on-demand -- this is all very
similar to the old fuzzer UI. Also inherited from the fuzzer UI is that
the build system communicates with web clients over a WebSocket
connection.
When the build finishes, if `--webui` was passed (i.e. if the web server
is running), the build runner does not terminate; it continues running
to serve web requests, allowing interactive control of the build system.
In the web interface is an overall "status" indicating whether a build
is currently running, and also a list of all steps in this build. There
are visual indicators (colors and spinners) for in-progress, succeeded,
and failed steps. There is a "Rebuild" button which will cause the build
system to reset the state of every step (note that this does not affect
caching) and evaluate the step graph again.
If `--time-report` is passed to `zig build`, a new section of the
interface becomes visible, which associates every build step with a
"time report". For most steps, this is just a simple "time taken" value.
However, for `Compile` steps, the compiler communicates with the build
system to provide it with much more interesting information: time taken
for various pipeline phases, with a per-declaration and per-file
breakdown, sorted by slowest declarations/files first. This feature is
still in its early stages: the data can be a little tricky to
understand, and there is no way to, for instance, sort by different
properties, or filter to certain files. However, it has already given us
some interesting statistics, and can be useful for spotting, for
instance, particularly complex and slow compile-time logic.
Additionally, if a compilation uses LLVM, its time report includes the
"LLVM pass timing" information, which was previously accessible with the
(now removed) `-ftime-report` compiler flag.
To make time reports more useful, ZIR and compilation caches are ignored
by the Zig compiler when they are enabled -- in other words, `Compile`
steps *always* run, even if their result should be cached. This means
that the flag can be used to analyze a project's compile time without
having to repeatedly clear cache directory, for instance. However, when
using `-fincremental`, updates other than the first will only show you
the statistics for what changed on that particular update. Notably, this
gives us a fairly nice way to see exactly which declarations were
re-analyzed by an incremental update.
If `--fuzz` is passed to `zig build`, another section of the web
interface becomes visible, this time exposing the fuzzer. This is quite
similar to the fuzzer UI this commit replaces, with only a few cosmetic
tweaks. The interface is closer than before to supporting multiple fuzz
steps at a time (in line with the overall strategy for this build UI,
the goal will be for all of the fuzz steps to be accessible in the same
interface), but still doesn't actually support it. The fuzzer UI looks
quite different under the hood: as a result, various bugs are fixed,
although other bugs remain. For instance, viewing the source code of any
file other than the root of the main module is completely broken (as on
master) due to some bogus file-to-module assignment logic in the fuzzer
UI.
Implementation notes:
* The `lib/build-web/` directory holds the client side of the web UI.
* The general server logic is in `std.Build.WebServer`.
* Fuzzing-specific logic is in `std.Build.Fuzz`.
* `std.Build.abi` is the new home of `std.Build.Fuzz.abi`, since it now
relates to the build system web UI in general.
* The build runner now has an **actual** general-purpose allocator,
because thanks to `--watch` and `--webui`, the process can be
arbitrarily long-lived. The gpa is `std.heap.DebugAllocator`, but the
arena remains backed by `std.heap.page_allocator` for efficiency. I
fixed several crashes caused by conflation of `gpa` and `arena` in the
build runner and `std.Build`, but there may still be some I have
missed.
* The I/O logic in `std.Build.WebServer` is pretty gnarly; there are a
*lot* of threads involved. I anticipate this situation improving
significantly once the `std.Io` interface (with concurrency support)
is introduced.
This is a correctness issue: When -fno-builtin is used, we must assume that we
could be compiling the memcpy/memset implementations, so generating calls to
them is problematic.
This commit allows using ZON (Zig Object Notation) in a few ways.
* `@import` can be used to load ZON at comptime and convert it to a
normal Zig value. In this case, `@import` must have a result type.
* `std.zon.parse` can be used to parse ZON at runtime, akin to the
parsing logic in `std.json`.
* `std.zon.stringify` can be used to convert arbitrary data structures
to ZON at runtime, again akin to `std.json`.
LLVM recently introduced new Triple::ArchType members in 19.1.3 which broke our
static assertions in zig_llvm.cpp. When implementing a fix for that, I realized
that we don't even need a lot of the stuff we have in zig_llvm.(cpp,h) anymore.
This commit trims the interface down considerably.
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`.
Passing it by value means that bringup on new architectures is harder for no
real benefit. Passing it by pointer allows to get the compiler running without
needing to figure out the C calling convention details first. This manifested in
practice on LoongArch, for example.
Most of the required renames here are net wins for readaibility, I'd
say. The ones in `arch` are a little more verbose, but I think better. I
didn't bother renaming the non-conflicting functions in
`arch/arm/bits.zig` and `arch/aarch64/bits.zig`, since these backends
are pretty bit-rotted anyway AIUI.
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.
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
mlugg: this is cherry-picked from Andrew's nosanitize branch (with
Jacob's fixes squashed in) since I needed this for `unpredictable` and
`prof` metadata. The nosanitize-specific changes are reverted in the
next commit.
Co-authored-by: Jacob Young <jacobly0@users.noreply.github.com>
Exposes sanitizer coverage flags to the target machine emit function.
Makes it easier to change sancov options without rebuilding the C++
files.
This also enables PCTable = true for sancov which is needed by AFL, and
adds the corresponding Clang flag.
* Add the `-ffuzz` and `-fno-fuzz` CLI arguments.
* Detect fuzz testing flags from zig cc.
* Set the correct clang flags when fuzz testing is requested. It can be
combined with TSAN and UBSAN.
* Compilation: build fuzzer library when needed which is currently an
empty zig file.
* Add optforfuzzing to every function in the llvm backend for modules
that have requested fuzzing.
* In ZigLLVMTargetMachineEmitToFile, add the optimization passes for
sanitizer coverage.
* std.mem.eql uses a naive implementation optimized for fuzzing when
builtin.fuzz is true.
Tracked by #20702
This reverts commit 397be0c9cc8156d38d1487a4c80210007033cbd0, reversing
changes made to 18d412ab2fb7bda92f7bfbdf732849bbcd066c33.
Caused test failures in master branch.
Without this data, debugger expressions try to pass structs by-value,
which mostly just crashes.
Also: mark enums as enum classes to prevent the enumerators from
shadowing other identifiers.
Now we get working global variable lookup in GDB! LLDB still re-mangles,
and it looks like we can't do much about that for now.
Also: translate non-owning type declarations into typedefs.
This will allow accessing non-local declarations from debuggers, which,
AFAICT, was impossible before.
Getting scopes right already works for type declarations and functions,
but will need some fiddling for variables:
For those, I tried imitating what Clang does for static member
variables, but LLDB tries to re-mangle those and then fails at lookup,
while GDB outright crashes. Hopefully I can find some other dwarven
incantation to do the right thing.
New OSs:
* XROS
* Serenity
* Vulkan
Removed OSs:
* Ananas
* CloudABI
* Minix
* Contiki
New CPUs:
* spirv
The removed stuff is removed from LLVM but not Zig.
