The overflow check for safe signed subtraction was using the formula (rhs < 0) == (lhs > result). This logic is flawed and incorrectly reports an overflow when the right-hand side is zero.
For the expression 42 - 0, this check evaluated to (0 < 0) == (42 > 42), which is false == false, resulting in true. This caused the generated SPIR-V to incorrectly branch to an OpUnreachable instruction, preventing the result from being stored.
Fixes#24281.
* resinator: Only preprocess when the input is an .rc file
* resinator: Fix include directory detection when cross-compiling from certain host archs
Previously, resinator would use the host arch as the target arch when looking for windows-gnu include directories. However, Zig only thinks it can provide a libc for targets specified in the `std.zig.target.available_libcs` array, which only includes a few for windows-gnu. Therefore, when cross-compiling from a host architecture that doesn't have a windows-gnu target in the available_libcs list, resinator would fail to detect the MinGW include directories.
Now, the custom option `/:target` is passed to `zig rc` which is intended for the COFF object file target, but can be re-used for the include directory target as well. For the include directory target, resinator will convert the MachineType to the relevant arch, or fail if there is no equivalent arch/no support for detecting the includes for the MachineType (currently 64-bit Itanium and EBC).
Fixes the `windows_resources` standalone test failing when the host is, for example, `riscv64-linux`.
Previously, resinator would use the host arch as the target arch when looking for windows-gnu include directories. However, Zig only thinks it can provide a libc for targets specified in the `std.zig.target.available_libcs` array, which only includes a few for windows-gnu. Therefore, when cross-compiling from a host architecture that doesn't have a windows-gnu target in the available_libcs list, resinator would fail to detect the MinGW include directories.
Now, the custom option `/:target` is passed to `zig rc` which is intended for the COFF object file target, but can be re-used for the include directory target as well. For the include directory target, resinator will convert the MachineType to the relevant arch, or fail if there is no equivalent arch/no support for detecting the includes for the MachineType (currently 64-bit Itanium and EBC).
Fixes the `windows_resources` standalone test failing when the host is, for example, `riscv64-linux`.
This is not meant to be a long-term solution, but it's the easiest thing
to get working quickly at the moment. The main intention of this hack is
to allow more tests to be enabled. By the time the coff linker is far
enough along to be enabled by default, this will no longer be required.
Also add a standalone test which covers the `-fentry` case. It does this
by performing two reproducible compilations which are identical other
than having different entry points, and checking whether the emitted
binaries are identical (they should *not* be).
Resolves: #23869
There will be more call sites to `preparePanicId` as we transition away
from safety checks in Sema towards safety checked instructions; it's
silly for them to all have this clunky usage.
This safety check was completely broken; it triggered unchecked illegal
behavior *in order to implement the safety check*. You definitely can't
do that! Instead, we must explicitly check the boundaries. This is a
tiny bit fiddly, because we need to make sure we do floating-point
rounding in the correct direction, and also handle the fact that the
operation truncates so the boundary works differently for min vs max.
Instead of implementing this safety check in Sema, there are now
dedicated AIR instructions for safety-checked intfromfloat (two
instructions; which one is used depends on the float mode). Currently,
no backend directly implements them; instead, a `Legalize.Feature` is
added which expands the safety check, and this feature is enabled for
all backends we currently test, including the LLVM backend.
The `u0` case is still handled in Sema, because Sema needs to check for
that anyway due to the comptime-known result. The old safety check here
was also completely broken and has therefore been rewritten. In that
case, we just check for 'abs(input) < 1.0'.
I've added a bunch of test coverage for the boundary cases of
`@intFromFloat`, both for successes (in `test/behavior/cast.zig`) and
failures (in `test/cases/safety/`).
Resolves: #24161
These conversion routines accept a `round` argument to control how the
result is rounded and return whether the result is exact. Most callers
wanted this functionality and had hacks around it being missing.
Also delete `std.math.big.rational` because it was only being used for
float conversion, and using rationals for that is a lot more complex
than necessary. It also required an allocator, whereas the new integer
routines only need to be passed enough memory to store the result.
and also rename `advancedPrint` to `bufferedPrint` in the zig init templates
These are left overs from my previous changes to zig init.
The new templating system removes LITNAME because the new restrictions on package names make it redundant with NAME, and the use of underscores for marking templated identifiers lets us template variable names while still keeping zig fmt happy.
Did you know that allocators reuse addresses? If not, then don't feel
bad, because apparently I don't either! This dumb mistake was probably
responsible for the CI failures on `master` yesterday.
I messed up atomic orderings on this variable because they changed in a
local refactor at some point. We need to always release on the store and
acquire on the loads so that a linker thread observing `.ready` sees the
stored MIR.
* Sema: allow binary operations and boolean not on vectors of bool
* langref: Clarify use of operators on vectors (`and` and `or` not allowed)
closes#24093
Looking at a compilation of 'test/behavior/x86_64/unary.zig' in
callgrind showed that a full 30% of the compiler runtime was spent in
this `stringToEnum` call, so optimizing it was low-hanging fruit.
We tried replacing it with nested `switch` statements using
`inline else`, but that generated too much code; it didn't emit huge
binaries or anything, but LLVM used a *ridiculous* amount of memory
compiling it in some cases. The core problem here is that only a small
subset of the cases are actually used (the rest fell through to an
"error" path), but that subset is computed at comptime, so we must rely
on the optimizer to eliminate the thousands of redundant cases. This
would be solved by #21507.
Instead, we pre-compute a lookup table at comptime. This table is pretty
big (I guess a couple hundred k?), but only the "valid" subset of
entries will be accessed in practice (unless a bug in the backend is
hit), so it's not too awful on the cache; and it performs much better
than the old `std.meta.stringToEnum` call.
Update the estimated total items for the codegen and link progress nodes
earlier. Rather than waiting for the main thread to dispatch the tasks,
we can add the item to the estimated total as soon as we queue the main
task. The only difference is we need to complete it even in error cases.
Without this cap, unlucky scheduling and/or details of what pipeline
stages perform best on the host machine could cause many gigabytes of
MIR to be stuck in the queue. At a certain point, pause the main thread
until some of the functions in flight have been processed.
This isn't really coherent to model as a `Feature`; this makes sense
because of zig1's specific environment. As such, I opted to check
`dev.env` directly.
Previously, `PerThread.populateTestFunctions` was analyzing the
`test_functions` declaration if it hadn't already been analyzed, so that
it could then populate it. However, the logic for doing this wasn't
actually correct, because it didn't trigger the necessary type
resolution. I could have tried to fix this, but there's actually a
simpler solution! If the `test_functions` declaration isn't referenced
or has a compile error, then we simply don't need to update it; either
it's unreferenced so its value doesn't matter, or we're going to get a
compile error anyway. Either way, we can just give up early. This avoids
doing semantic analysis after `performAllTheWork` finishes.
Also, get rid of the "Code Generation" progress node while updating the
test decl: this is a linking task.
glibc, freebsd, and netbsd all do caching manually, because of the fact
that they emit multiple files which they want to cache as a block.
Therefore, the individual sub-compilation on a cache miss should be
using `CacheMode.none` so that we can specify the output paths for each
sub-compilation as being in the shared output directory.
* "Flush" nodes ("LLVM Emit Object", "ELF Flush") appear under "Linking"
* "Code Generation" disappears when all analysis and codegen is done
* We only show one node under "Semantic Analysis" to accurately convey
that analysis isn't happening in parallel, but rather that we're
pausing one task to do another
