This commit adds a new transform that converts reflect Implements()
calls to runtime.interfaceImplements. At the moment, the Implements()
method is not yet implemented (how ironic) but if the value passed to
Implements is known at compile time the method call can be optimized to
runtime.interfaceImplements to make it a regular interface assert.
This commit is the last change necessary to add basic support for the
encoding/json package. The json package is certainly not yet fully
supported, but some trivial objects can be converted to JSON.
This distinction was useful before when reflect wasn't properly
supported. Back then it made sense to only include method sets that were
actually used in an interface. But now that it is possible to get to
other values (for example, by extracting fields from structs) and it is
possible to turn them back into interfaces, it is necessary to preserve
all method sets that can possibly be used in the program in a type
assert, interface assert or interface method call.
In the future, this logic will need to be revisited again when
reflect.New or reflect.Zero gets implemented.
Code size increases a bit in some cases, but usually in a very limited
way (except for one outlier in the drivers smoke tests). The next commit
will improve the situation significantly.
This doesn't yet add support for actually making use of variadic
functions, but at least allows (unintended) variadic functions like the
following to work:
void foo();
This change extends defer support to all supported builitin functions.
Not all of them make sense (such as len, cap, real, imag, etc) but this
change for example adds support for `defer(delete(m, key))` which is
used in the Go 1.15 encoding/json package.
This works around some UB in LLVM, where an out-of-bounds conversion would produce a poison value.
The selected behavior is saturating, except that NaN is mapped to the minimum value.
Before this change, the compiler could panic with the following message:
panic: 20 not an Int
That of course doesn't make much sense. But it apparently is expected
behavior, see https://github.com/golang/go/issues/43165 for details.
This commit fixes this issue by converting the constant to an integer if
needed.
This appears to be allowed by the specification, at least it is allowed
by the main Go implementation: https://play.golang.org/p/S8jxAMytKDB
Allow it in TinyGo too, for consistency.
Found because it is triggered with `tinygo test flags`. This doesn't
make the flags package pass all tests, but is a step closer.
It can be unexpected that printing a float32 involves 64-bit floating
point routines, see for example:
https://github.com/tinygo-org/tinygo/issues/1415
This commit adds a dedicated printfloat32 instead just for printing
float32 values. It comes with a possible code size increase, but only if
both float32 and float64 values are printed. Therefore, this should be
an improvement in almost all cases.
I also tried using printfloat32 for everything (and casting a float64 to
float32 to print) but the printed values are slightly different,
breaking the testdata/math.go test for example.
There were a few cases left where a named type would cause a crash in
the compiler. While going through enough code would have found them
eventually, I specifically looked for the `Type().(` pattern: a Type()
call that is then used in a type assert. Most of those were indeed bugs,
although for some I couldn't come up with a reproducer so I left them
as-is.
Previously, a blocking select on a nil channel would result in a nil panic inside the channel runtime code.
This change fixes the nil checks so that the select works as intended.
Previously, the typecode was passed via a direct reference, which results in invalid IR when the defer is not reached in all return paths.
It also results in incorrect behavior if the defer is in a loop, causing all defers to use the typecode of the last iteration.
The main change is in building the libraries, where -fshort-enums was
passed on RISC-V while other C files weren't compiled with this setting.
Note: the test already passed before this change, but it seems like a
good idea to explicitly test for enum size consistency.
There is also not a particular reason not to pass -fshort-enums on
RISC-V. Perhaps it's better to do it there too (on baremetal targets
that don't have to worry about binary compatibility).
This is the kind that is used in Go (actually CGo) for exporting
functions. I think it's best to use //export instead of our custom
//go:export pragma, for consistency (they are equivalent in TinyGo).
Therefore I've updated all instances to the standard format (except for
two that are updated in https://github.com/tinygo-org/tinygo/pull/1024).
No smoke tests changed (when comparing the output hash), except for some
wasm tests that include DWARF debug info and tend to be flaky anyway.
This is used for example by the errors package, which contains:
if x, ok := err.(interface{ As(interface{}) bool }); ok && x.As(target) {
return true
}
The interface here is not a named type.
Previously, the compiler used LLVM's shift instructions directly, which have UB whenever the shifts are large or negative.
This commit adds runtime checks for negative shifts, and handles oversized shifts.
This is necessary for better CGo support on bare metal. Existing
libraries expect to be able to include parts of libc and expect to be
able to link to those symbols.
Because with this all targets have a working libc, it is now possible to
add tests to check that a libc in fact works basically.
Not all parts of picolibc are included, such as the math or stdio parts.
These should be added later, when needed.
This commit also avoids the need for the custom memcpy/memset/memcmp
symbols that are sometimes emitted by LLVM. The C library will take care
of that.
Non-constant type asserts are not yet implemented, but should be
relatively easy to add at a later time. They should result in a clear
error message for now.
This patch is a combination of two related changes:
1. The compiler now allows other types than `int` when specifying the
size of a channel in a make(chan ..., size) call.
2. The compiler now checks for maximum allowed channel sizes. Such
checks are trivially optimized out in the vast majority of cases as
channel sizes are usually constant.
I discovered this issue when trying out channels on AVR.
Previously using defer with an exported function generated an invalid function call due to differences between TinyGo's calling convention and the C calling convention.
This might sound crazy, but I think it's better to enable the GC by
default to avoid surprises. It costs 1130 bytes of flash and 16 bytes of
RAM (plus heap overhead) so it's not exactly free, but if needed it can
easily be disabled with `-gc=leaking`. On the Uno (32kB flash, 2kB RAM)
that's not massive, on the DigiSpark (8kB flash, 0.5kB RAM) that may be
too much depending on the application.
This implementation simply casts types without special support to an
interface, to make the implementation simpler and possibly reducing the
code size too. It will likely be slower than the canonical Go
implementation though (which builds special compare and hash functions
at compile time).
Instead of putting the magic in the AST, generate regular accessor
methods. This avoids a number of special cases in the compiler, and
avoids missing any of them.
The resulting union accesses are somewhat clunkier to use, but the
compiler implementation has far less coupling between the CGo
implementation and the IR generator.
Ayke van Laethem
Takeshi Yoneda
Nia Weiss
Takeshi Yoneda
waj334
Cornel
cornelk
Jaden Weiss