Over the last year of using std.log in practice, it has become clear to
me that having the current 8 distinct log levels does more harm than
good. It is too subjective which level a given message should have which
makes filtering based on log level weaker as not all messages will have
been assigned the log level one might expect.
Instead, more granular filtering should be achieved by leveraging the
logging scope feature. Filtering based on a combination of scope and log
level should be sufficiently powerful for all use-cases.
Note that the self hosted compiler has already limited itself to 4
distinct log levels for many months and implemented granular filtering
based on both log scope and level. This has worked very well in practice
while working on the self hosted compiler.
The TLS area may be located in the upper part of the address space and,
if the platform expects a constant offset to be applied, may make the tp
register calculation overflow.
Use +% instead of +, the overflow is harmless.
After a discussion about language specs, this seems like the best way to
go, because it's simpler to reason about both for humans and compilers.
The `bitcast_result_ptr` ZIR instruction is no longer needed.
This commit also implements writing enums, arrays, and vectors to
virtual memory at compile-time.
This unlocked some more of compiler-rt being able to build, which
in turn unlocks saturating arithmetic behavior tests.
There was also a memory leak in the comptime closure system which is now
fixed.
AIR:
* div is renamed to div_trunc.
* Add div_float, div_floor, div_exact.
- Implemented in Sema and LLVM codegen. C backend has a stub.
Improvements to std.math.big.Int:
* Add `eqZero` function to `Mutable`.
* Fix incorrect results for `divFloor`.
Compiler-rt:
* Add muloti4 to the stage2 section.
This fixes InstallRawStep to handle the cases when there are empty segments (segments with no sections). Before this change, if there was an empty segment with no sections, then the fixup of binaryOffsets is skipped. This fixes that by looping through each segment until a non-empty one is found and then fixing up the sections. This fixed an issue I was having with InstallRawStep for a bootloader I'm writing.
This modifies the error for an unexpected exit code from the ChildProcess of RunStep to be UnexpectedExitCode rather than UncleanExit. This allows the handler of the error to distinguish between an error reported by the ChildProcess, and an error executing the ChildProcess, which is an important dinstinction when it comes to know what information to report to the user. For example, if you have a ChildProcess that you know reports its own errors, an unexpected exit code would mean the error is already reported, but an unclean exit would mean that child process was not able to report any error.
* std.os: take advantage of `@minimum`. It's probably time to
deprecate `std.min` and `std.max`.
* New AIR instructions: min and max
* Introduce SIMD vector support to stage2
* Add `@Type` support for vectors
* Sema: add `checkSimdBinOp` which can be re-used for other arithmatic
operators that want to support vectors.
* Implement coercion from vectors to arrays.
- In backends this is handled with bitcast for vector to array,
however maybe we want to reduce the amount of branching by
introducing an explicit AIR instruction for it in the future.
* LLVM backend: implement lowering vector types
* Sema: Implement `slice.ptr` at comptime
* Value: improve `numberMin` and `numberMax` to support floats in
addition to integers, and make them behave properly in the presence
of NaN.
* work around a stage1 miscompilation leading to the wrong integer
comparison predicate being emitted.
* fix the bug of not annotating callsites with the calling convention
of the callee, leading to undefined behavior.
* add the `nobuiltin` attribute when building freestanding libc or
compiler_rt libraries to prevent e.g. memcpy from being "optimized"
into a call to itself.
* compiler-rt: change a call to be comptime to make the generated LLVM
IR simpler and easier to study.
I still can't enable the widening tests due to the compiler-rt compare
function being miscompiled in some not-yet-diagnosed way.
libc requires this to use `long double` which is sometimes the same as
f128, sometimes not.
Also for an unknown reason, aarch64 is getting an invalid result for the
`@mulAdd` behavior test for f128. See #9900.
* move fmaq from freestanding libc to compiler_rt, unconditionally
exported weak_odr.
* stage1: add fmaf, fmal, fmaq as symbols that compiler-rt might
generate calls to.
* stage1: lower `@mulAdd` directly to a call to `fmaq` instead of to
the LLVM intrinsic because LLVM will lower it to `fmal` even when the
target's `long double` is not equivalent to `f128`.
This commit is intended to fix the test suite which is failing on the
previous commit.
std: add f128 implementations of fma, frexp, and ilogb. Expose `fmal` in
zig's freestanding libc. This makes `@mulAdd` work correctly for f128.
Fixes a CI regression from yesterday, where I added a usage of f128
`@mulAdd` into the self-hosted compiler.
Before, Sema for comptime `@bitCast` would return the same Value but
change the Type. This gave invalid results because, for example, an
integer Value when the Type is a float would be interpreted numerically,
but `@bitCast` needs it to reinterpret how they would be stored in
memory.
This requires a mechanism to serialize a Value to a byte buffer and
deserialize a Value from a byte buffer.
Not done yet, but needs to happen: comptime dereferencing a pointer
to a Decl needs to perform a comptime bitcast on the loaded value.
Currently the value is silently wrong in the same way that `@bitCast`
was silently wrong before this commit.
The logic in Value for handling readFromMemory for large integers is
only correct for small integers. It needs to be fleshed out for proper
big integers.
As part of this change:
* std.math.big.Int: initial implementations of readTwosComplement and
writeTwosComplement. They only support bit_count <= 128 so far and
panic otherwise.
* compiler-rt: move the compareXf2 exports over to the stage2 section.
Even with the improvements in this commit, I'm still seeing test
failures in the widening behavior tests; more investigation is
needed.
