Move these asserts into compiler/asserts.go, to keep them together.
The make([]T) asserts aren't moved yet because that code is (still!)
quite ugly and in need of some clean up.
This commit implements nil checks for all platforms. These nil checks
can be optimized on systems with a MMU, but since a major target is
systems without MMU, keep it this way for now.
It implements three checks:
* Nil checks before dereferencing a pointer.
* Nil checks before calculating an address (*ssa.FieldAddr and
*ssa.IndexAddr)
* Nil checks before calling a function pointer.
The first check has by far the biggest impact, with around 5% increase
in code size. The other checks only trigger in only some test cases and
have a minimal impact on code size.
This first nil check is also the one that is easiest to avoid on systems
with MMU, if necessary.
Whenever interp hits an unreachable instruction, it bails out at that
point. However, it used to insert new instructions at the bottom with
the old init calls still at the top. So when a panic() happened in a
non-main package, the last packages to init would actually be called
first.
This commit fixes this by setting the insert point at the top of
runtime.initAll before starting interpretation, so the initialization
order is still correct when a panic() happens during init.
The wasm_exec.js file copied from the main Go repository did write those
values to address 4096 in linear memory, which led to memory corruption
in linear memory. Remove these things for now, until they're actually
supported, if support is ever added.
The WebAssembly target is not yet considered stable in LLVM 7, but has
been enabled in the Debian builds so tests can run on Debian. However,
the Homebrew builds don't have it enabled which results in test
failures.
Temporarily run WebAssembly tests only on Linux to fix this. This can be
reverted after a switch to LLVM 8, which has WebAssembly enabled by
default.
In LLVM 8, the AVR backend has moved all function pointers to address
space 1 by default. Much of the code still assumes function pointers
live in address space 0, leading to assertion failures.
This commit fixes this problem by autodetecting function pointers and
avoiding them in interface pseudo-calls.
Without this, the following code would not panic:
func getInt(i int) { return i }
make([][1<<18], getInt(1<<18))
Or this code would be allowed to compile for 32-bit systems:
make([][1<<18], 1<<18)
Previously, this would have resulted in a LLVM verification error
because runtime.sliceBoundsCheckMake would not accept 64-bit integers on
these platforms.
Unfortunately, the olin/cwa emulator does not handle floats correctly.
Node.js does, and because it is also supported by the Go WebAssembly
implementation it has better support in general.
CircleCI is faster and has more features than Travis CI. Additionally,
based on the recent news, the future of Travis CI is rather uncertain.
Keep using Travis CI for macOS testing at the moment, as open source
projects will need to get special permission to use CircleCI for macOS
tests.
The interp package does a much better job at interpretation, and is
implemented as a pass on the IR which makes it much easier to compose.
Also, the implementation works much better as it is based on LLVM IR
instead of Go SSA.
Match data layout of complex numbers to that of Clang, for better
interoperability. This makes alignment of complex numbes the same as the
individual elements (real and imaginary), as is required by the C spec
and implemented in Clang, but unlike the gc compler. The Go language
specification is silent on this matter.
> Each complex type has the same object representation and alignment
> requirements as an array of two elements of the corresponding real
> type (float for float complex, double for double complex, long double
> for long double complex). The first element of the array holds the
> real part, and the second element of the array holds the imaginary
> component.
Source: https://en.cppreference.com/w/c/language/arithmetic_types
