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.
These names aren't matching any formal specification; they're mostly
just ripped from LLVM code. Therefore, we should definitely follow Zig
naming conventions here.
Most of these changes seem like improvements. The PDB thing had a TODO
saying it used to crash; I anticipate it works now, we'll see what CI
does.
The `std.os.uefi` field renames are a notable breaking change.
because it marks the linker section, preventing garbage collection.
Also, name the members because that is required by this intrinsic.
Also, enable the StackDepth option in the sancov pass as a workaround
for https://github.com/llvm/llvm-project/pull/106464, otherwise, LLVM
enables TracePCGuard even though we explicitly disable it.
This matches what LLVM's sancov pass does and is required so that
optimization passes do not delete the instrumentation.
However, this is currently triggering an error: "members of
llvm.compiler.used must be named" so the next commit will add names to
those globals.
It's useful to have TraceCmp based on the results of LLVM optimizations,
while the code coverage bits were emitted by Zig manually, allowing more
careful correlation to points of interest in the source code.
This re-enables the sancov pass in `-ffuzz` mode, but only TraceCmp.
Notably, IndirectCalls is off, which needs to be implemented manually in
the LLVM backend, and StackDepth remains off, because it is not used by
libfuzzer or AFL either.
If stack depth is re-introduced, it can be done with better performance
characteristics by being function call graph aware, and only lowered in
call graph cycles, where its heuristic properties come in useful.
Fixes the fuzzing regression.
instead of relying on the LLVM sancov pass. The LLVM pass is still
executed if trace_pc_guard is requested, disabled otherwise. The LLVM
backend emits the instrumentation directly.
It uses `__sancov_pcs1` symbol name instead of `__sancov_pcs` because
each element is 1 usize instead of 2.
AIR: add CoveragePoint to branch hints which indicates whether those
branches are interesting for code coverage purposes.
Update libfuzzer to use the new instrumentation. It's simplified since
we no longer need the constructor and the pcs are now in a continguous
list.
This is a regression in the fuzzing functionality because the
instrumentation for comparisons is no longer emitted, resulting in worse
fuzzer inputs generated. A future commit will add that instrumentation
back.
These won't live in the parent namespace as decls which causes problems
later in this function, and tests are guaranteed not to be referenced at
comptime anyway, so there's actually no need to run this logic.
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.
Grepping for `NO_THUMB` in glibc suggests that glibc does not actually support
pure Thumb-2 mode. This is the mode that is implied by these target triples;
mixed Arm/Thumb mode should just use the regular `arm*-linux-gnueabi*` triples.
Andrew Kelley