- This ensures we honor the user's integer size when performing wrapping operations.
- Also, instead of using ensureCapacity, we now use ensureUnusedCapacity.
After this change, the frontend and backend cooperate to keep track of
which Decls are actually emitted into the machine code. When any backend
sees a `decl_ref` Value, it must mark the corresponding Decl `alive`
field to true.
This prevents unused comptime data from spilling into the output object
files. For example, if you do an `inline for` loop, previously, any
intermediate value calculations would have gone into the object file.
Now they are garbage collected immediately after the owner Decl has its
machine code generated.
In the frontend, when it is time to send a Decl to the linker, if it has
not been marked "alive" then it is deleted instead.
Additional improvements:
* Resolve type ABI layouts after successful semantic analysis of a
Decl. This is needed so that the backend has access to struct fields.
* Sema: fix incorrect logic in resolveMaybeUndefVal. It should return
"not comptime known" instead of a compile error for global variables.
* `Value.pointerDeref` now returns `null` in the case that the pointer
deref cannot happen at compile-time. This is true for global
variables, for example. Another example is if a comptime known
pointer has a hard coded address value.
* Binary arithmetic sets the requireRuntimeBlock source location to the
lhs_src or rhs_src as appropriate instead of on the operator node.
* Fix LLVM codegen for slice_elem_val which had the wrong logic for
when the operand was not a pointer.
As noted in the comment in the implementation of deleteUnusedDecl, a
future improvement will be to rework the frontend/linker interface to
remove the frontend's responsibility of calling allocateDeclIndexes.
I discovered some issues with the plan9 linker backend that are related
to this, and worked around them for now.
* less branching by passing parameters in the main op code switch.
* properly pass the target when asking the type system for int info.
* handle u8, i16, etc when it is represented using
int_unsigned/int_signed tag.
* compile error instead of assertion failure for unimplemented cases
(greater than 64 bits integer).
* control flow cleanups
* zig.h: expand macros into inline functions
* reduce the complexity of the test case by making it one test case
that calls multiple functions. Also fix the problem of c_int max
value mismatch between host and target.
* Inferred error sets are stored in the return Type of the function,
owned by the Module.Fn. So it cleans up that memory in deinit().
* Sema: update the inferred error set in zirRetErrValue
- Update relevant code in wrapErrorUnion
* C backend: improve some some instructions to take advantage of
liveness analysis to avoid being emitted when unused.
* C backend: when an error union has a payload type with no runtime
bits, emit the error union as the same type as the error set.
* implement enough of ret_err_value to pass wasm tests
* only do the proper `@panic` implementation for the backends which
support it, which is currently only the C backend. The other backends
will see `@breakpoint(); unreachable;` same as before.
- I plan to do AIR memory layout reworking as a prerequisite to
fixing other backends, because that will help me put all the
constants up front, which will allow the codegen to lower to memory
without jumps.
* `@panic` is implemented using anon decls for the message. Makes it
easier on the backends. Might want to look into re-using decls for
this in the future.
* implement DWARF .debug_info for pointer-like optionals.
* ZIR: add two instructions:
- ret_err_value_code
- ret_err_value
* AstGen: add countDefers and utilize it to emit more efficient ZIR for
return expressions in the presence of defers.
* AstGen: implement |err| payloads for `errdefer` syntax.
- There is not an "unused capture" error for it yet.
* AstGen: `return error.Foo` syntax gets a hot path in return
expressions, using the new ZIR instructions. This also is part of
implementing inferred error sets, since we need to tell Sema to add
an error value to the inferred error set before it gets coerced.
* Sema: implement `@setCold`.
- Implement `@setCold` support for C backend.
* `@panic` and regular safety panics such as `unreachable` now properly
invoke `std.builtin.panic`.
* C backend: improve pointer and function value rendering.
* C linker: fix redundant typedefs.
* Add Type.error_set_inferred.
* Fix Value.format for enum_literal, enum_field_index, bytes.
* Remove the C backend test that checks for identical text
I measured a 14% reduction in Total ZIR Bytes from master branch
for std/os.zig.
It now displays the byte with proper printability handling. This makes
the relevant compile error test case no longer a regression in quality
from stage1 to stage2.
The motivation for this commit is that there exists source files which
produce ast-check errors, but crash stage1 or otherwise trigger stage1
bugs. Previously to this commit, Zig would run AstGen, collect the
compile errors, run stage1, report stage1 compile errors and exit if
any, and then report AstGen compile errors.
The main change in this commit is to report AstGen errors prior to
invoking stage1, and in fact if any AstGen errors occur, do not invoke
stage1 at all.
This caused most of the compile error tests to fail due to things such
as unused local variables and mismatched stage1/stage2 error messages.
It was taking a long time to update the test cases one-by-one, so I
took this opportunity to unify the stage1 and stage2 testing harness,
specifically with regards to compile errors. In this way we can start
keeping track of which tests pass for 1, 2, or both.
`zig build test-compile-errors` no longer works; it is now integrated
into `zig build test-stage2`.
This is one step closer to executing compile error tests in parallel; in
fact the ThreadPool object is already in scope.
There are some cases where the stage1 compile errors were actually
better; those are left failing in this commit, to be addressed in a
follow-up commit.
Other changes in this commit:
* build.zig: improve support for -Dstage1 used with the test step.
* AstGen: minor cosmetic changes to error messages.
* stage2: add -fstage1 and -fno-stage1 flags. This now allows one to
download a binary of the zig compiler and use the llvm backend of
self-hosted. This was also needed for hooking up the test harness.
However, I realized that stage1 calls exit() and also has memory
leaks, so had to complicate the test harness by not using this flag
after all and instead invoking as a child process.
- These CLI flags will disappear once we start shipping the
self-hosted compiler as the main compiler. Until then, they can be
used to try out the work-in-progress stage2.
* stage2: select the LLVM backend by default for release modes, as long
as the target architecture is supported by LLVM.
* test harness: support setting the optimize mode
* Remove parser error on double ampersand
* Add failing test for double ampersand case
* Add error when encountering double ampersand in AstGen
"Bit and" operator should not make sense when one of its operands
is an address.
* Check that 2 ampersands are adjacent to each other in source string
* Remove cases of unused variables in tests
Since v0.23 release of Wasmtime, if we want to iterate a directory
Y then directory Y needed to have been granted `fd_readdir` right.
However, it is now also required for directory X to carry `fd_readdir`
right, and so on, up-chain all the way until we reach the preopen
(which possesses all rights by default).
This caused problems for us since our libstd implementation is more
fine-grained and allowed for parent dirs not to carry the right while
allow for iterating on its children. My proposal here is to always
grant `fd_readdir` right as part of
`std.fs.Dir.OpenDirOptions.access_sub_paths`. This seems to be the
approach taken by Rust also, plus we should be justified to take this
approach since WASI is experimental and snapshot1 will be discontinued
eventually and replaced with a new approach to access management
that will require a complete rewrite of our libstd anyhow.
Before this, if a compile error occurred, it would cause the previous
value for e.g. the function scope to not get reset. If the AstGen
process continued, it would result in a violation of the data
guarantees that it relies on.
This commit takes advantage of defer to ensure the previous value is
always reset, even in the case of an error.
Closes#8920
This allows us to differentiate between regular locals and variables that create multiple locals
on the stack such as optionals and structs.
Now `struct_a = struct_b;` works and only updates a reference, rather than update all local's values.
Also created more test cases to test against this.
- When returning within a block, we must use an explicit return opcode. For now always emit the opcode when calling return, rather than using implicit return statements.
- Also added a more comprehensive test case to test for enum values using conditions
When scanDecls happens, we create stub Decl objects that
have not been semantically analyzed. When they get referenced,
they get semantically analyzed.
Before this commit, when they got unreferenced, they were completely
deleted, including deleted from the containing Namespace.
However, if the update did not cause the containing Namespace to get
deleted, for example, if `std.builtin.ExportOptions` is no longer
referenced, but `std.builtin` is still referenced, and then `ExportOptions`
gets referenced again, the Namespace would be incorrectly missing the
Decl, so we get an incorrect "no such member" error.
The solution is to, when dealing with a no longer referenced Decl
objects during an update, clear them to the state they would be in
on a fresh scanDecl, rather than completely deleting them.
Conflicts:
* src/codegen/spirv.zig
* src/link/SpirV.zig
We're going to want to improve the stage2 test harness to print
the source file name when a compile error occurs otherwise std lib
contributors are going to see some confusing CI failures when they cause
stage2 AstGen compile errors.
In order for this test to pass, the host linking/start code needs to
support explicitly setting the stack size. Zig defaults to 16 MiB stack
size, which is enough to pass the test in Debug builds, however, most
operating systems do not honor the stack size we request for and give a
smaller amount.
Eventually the goal is to pass this test on all hosts.
* Advance line and PC prior to ending sequence in debug line program
for a fn_decl. This is equivalent to closing scope in the debugger
and without it, the debugger will not map source-to-address info
as a result will not print the source when breaking at a symbol.
* Fix debug aranges sentinels to be of the size as the actual tuple
descriptor (assuming segment selector to be ommitted). In summary,
the sentinels were 32bit 0s, whereas they ought to be 64bit 0s.
* Make naming of symbols in the binary more consistent by prefixing
each symbol name with an underscore '_'.
