This avoids the following error:
```
error: incompatible pointer types passing 'int64_t *' (aka 'long long *') to parameter of type 'long *'
overflow = __builtin_saddl_overflow(lhs, rhs, res);
^~~
```
My previous understanding was that this error would not occur because
prior to this line we check that int64_t is equivalent to long, like
this:
```c
```
However, it appears that this is still a warning in C if int64_t is
primarily aliased to `long long`, even though `long` and `long long` are
the same thing.
Most of the work here was additions to zig.h. The lowering code is
mainly responsible for calling the correct function name depending on
the operand type.
Some of the compiler-rt calls here are not implemented yet and are
non-standard symbols due to the C programming language not needing them.
After this commit, the behavior tests with -ofmt=c are passing again.
Compilers will sometimes `#define linux 1` if the operating system in
use is Linux. This clashes with the code produced by the C backend when
processing the stdlib, e.g. std.Target.Os.VersionRange [^1] which is a
struct containing a field named `linux`.
The output of the C backend doesn't rely on this macro being defined,
and other code also shouldn't rely on it -- e.g. quoting from the GCC
documentation [^2]:
"""
The C standard requires that all system-specific macros be part of
the reserved namespace. All names which begin with two underscores, or
an underscore and a capital letter, are reserved for the compiler and
library to use as they wish. However, historically system-specific
macros have had names with no special prefix; for instance, it is
common to find unix defined on Unix systems.
[...]
We are slowly phasing out all predefined macros which are outside the
reserved namespace. You should never use them in new programs, and we
encourage you to correct older code to use the parallel macros
whenever you find it. We don’t recommend you use the system-specific
macros that are in the reserved namespace, either. It is better in the
long run to check specifically for features you need
"""
[^1]: 8c32d989c9/lib/std/target.zig (L224)
[^2]: https://gcc.gnu.org/onlinedocs/cpp/System-specific-Predefined-Macros.html#System-specific-Predefined-Macros
This also surfaces the fact that clz, ctz and popCount didn't actually
support 128 bit integers, despite what was claimed by
226fcd7c709ec664c5d883042cf7beb3026f66cb. This was partially hidden by
the fact that the test code for popCount only exercised 128 bit integers
in a comptime context. This commit duplicates that test case for runtime
ints too.
This parameter is only currently needed by zig_byte_swap() and
zig_bit_reverse(). This commit adds an option to airBuiltinCall() to
allow emitting the signedness information only when needed, removing
this unused parameter from the other builtins.
This folds the airCountZeroes() code from
226fcd7c709ec664c5d883042cf7beb3026f66cb back into airBuiltinCall(),
since most of these builtins happen to require the same arguments and
can be unified under a common function signature.
* AIR: use pl_op instead of ty_pl for wasm_memory_size. No need to
store the type because the type is always `u32`.
* AstGen: use coerced_ty for `@wasmMemorySize` and `@wasmMemoryGrow`
and do the coercions in Sema.
* Sema: use more accurate source locations for errors.
* Provide more information in the compiler error message.
* Codegen: use liveness data to avoid lowering unused
`@wasmMemorySize`.
* LLVM backend: add implementation
- I wasn't able to test it because we are hitting a linker error for
`-target wasm32-wasi -fLLVM`.
* C backend: use `zig_unimplemented()` instead of silently doing wrong
behavior for these builtins.
* behavior tests: branch only on stage2_arch for inclusion of the
wasm.zig file. We would change it to `builtin.cpu.arch` but that is
causing a compiler crash on some backends.
This implements the wasm builtins by lowering to builtins that are supported by c-compilers.
In this case: Clang.
This also simplifies the `AIR` instruction as it now uses the payload field of `ty_pl` and `pl_op`
directly to store the index argument rather than storing it inside Extra. This saves us 4 bytes
per builtin call.
There are some restrictions here.
- We either need C11 or a compiler that supports the aligned attribute
- We cannot provide align less than the type's natural C alignment.
This reverts commit d48e4245b68bf25c7f41804a5012ac157a5ee546.
I have no idea why this is failing Drone CI, but in a branch, reverting
this commit solved the problem.
* Remove the builtins `@addWithSaturation`, `@subWithSaturation`,
`@mulWithSaturation`, and `@shlWithSaturation` now that we have
first-class syntax for saturating arithmetic.
* langref: Clarify the behavior of `@shlExact`.
* Ast: rename `bit_shift_left` to `shl` and `bit_shift_right` to `shr`
for consistency.
* Air: rename to include underscore separator with consistency with
the rest of the ops.
* Air: add shl_exact instruction
* Use non-extended tags for saturating arithmetic, to keep it
simple so that all the arithmetic operations can be done the same
way.
- Sema: unify analyzeArithmetic with analyzeSatArithmetic
- implement comptime `+|`, `-|`, and `*|`
- allow float operands to saturating arithmetic
* `<<|` allows any integer type for the RHS.
* C backend: fix rebase conflicts
* LLVM backend: reduce the amount of branching for arithmetic ops
* zig.h: fix magic number not matching actual size of C integer types
- modify AstGen binOpExt()/assignBinOpExt() to accept generic extended payload T
- rework Sema zirSatArithmetic() to use existing sema.analyzeArithmetic() by adding an `opt_extended` parameter.
- add airSatOp() to codegen/c.zig
- add saturating functions to src/link/C/zig.h
* langref: add some more "see also" links for atomics
* Add the following AIR instructions
- atomic_load
- atomic_store_unordered
- atomic_store_monotonic
- atomic_store_release
- atomic_store_seq_cst
- atomic_rmw
* Implement those AIR instructions in LLVM and C backends.
* AstGen: make the `ty` result locations for `@atomicRmw`, `@atomicLoad`,
and `@atomicStore` be `coerced_ty` to avoid unnecessary ZIR
instructions when Sema will be doing the coercions redundantly.
* Sema for `@atomicLoad` and `@atomicRmw` is done, however Sema for
`@atomicStore` is not yet implemented.
- comptime eval for `@atomicRmw` is not yet implemented.
* Sema: flesh out `coerceInMemoryAllowed` a little bit more. It can now
handle pointers.
* Implement Sema for `@cmpxchgWeak` and `@cmpxchgStrong`. Both runtime
and comptime codepaths are implement.
* Implement Codegen for LLVM backend and C backend.
* Add LazySrcLoc.node_offset_builtin_call_argX 3...5
* Sema: rework comptime control flow.
- `error.ComptimeReturn` is used to signal that a comptime function
call has returned a result (stored in the Inlining struct).
`analyzeCall` notices this and handles the result.
- The ZIR instructions `break_inline`, `block_inline`,
`condbr_inline` are now redundant and can be deleted. `break`,
`block`, and `condbr` function equivalently inside a comptime scope.
- The ZIR instructions `loop` and `repeat` also are modified to
directly perform comptime control flow inside a comptime scope,
skipping an unnecessary mechanism for analysis of runtime code.
This makes Zig perform closer to an interpreter when evaluating
comptime code.
* Sema: zirRetErrValue looks at Sema.ret_fn_ty rather than sema.func
for adding to the inferred error set. This fixes a bug for
inlined/comptime function calls.
* Implement ZIR printing for cmpxchg.
* stage1: make cmpxchg respect --single-threaded
- Our LLVM C++ API wrapper failed to expose this boolean flag before.
* Fix AIR printing for struct fields showing incorrect liveness data.
* 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.
* 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.
Decl objects need to know whether they are the owner of the Type/Value
associated with them, in order to decide whether to destroy the
associated Namespace, Fn, or Var when cleaning up.
* std.ArrayList gains `moveToUnmanaged` and dead code
`ArrayListUnmanaged.appendWrite` is deleted.
* emit_h state is attached to Module rather than Compilation.
* remove the implementation of emit-h because it did not properly
integrate with incremental compilation. I will re-implement it
in a follow-up commit.
* Compilation: use the .codegen_failure tag rather than
.dependency_failure tag for when `bin_file.updateDecl` fails.
C backend:
* Use a CValue tagged union instead of strings for C values.
* Cleanly separate state into Object and DeclGen:
- Object is present only when generating a .c file
- DeclGen is present for both generating a .c and .h
* Move some functions into their respective Object/DeclGen namespace.
* Forward decls are managed by the incremental compilation frontend; C
backend no longer renders function signatures based on callsites.
For simplicity, all functions always get forward decls.
* Constants are managed by the incremental compilation frontend. C
backend no longer has a "constants" section.
* Participate in incremental compilation. Each Decl gets an ArrayList
for its generated C code and it is updated when the Decl is updated.
During flush(), all these are joined together in the output file.
* The new CValue tagged union is used to clean up using of assigning to
locals without an additional pointer local.
* Fix bug with bitcast of non-pointers making the memcpy destination
immutable.
