It should only be added at the point that it is needed, for example when
using libclang or using the built-in Clang. It isn't needed when running
an external tool.
This patch adds //go: pragmas directly to declared functions and
globals found during CGo processing. This simplifies the logic in the
compiler: it no longer has to consider special "C." prefixed function
names. It also makes the cgo pass more flexible in the pragmas it emits
for functions and global variables.
For example, the following did not work before but does work with this
change:
// int add(int a, int b) {
// return a + b;
// }
import "C"
func main() {
println("add:", C.add(3, 5))
}
Even better, the functions in the header are compiled together with the
rest of the Go code and so they can be optimized together! Currently,
inlining is not yet allowed but const-propagation across functions
works. This should be improved in the future.
This commit changes a target triple like "armv6m-none-eabi" to
"armv6m-unknown-unknow-eabi". The reason is that while the former is
correctly parsed in Clang (due to normalization), it wasn't parsed
correctly in LLVM meaning that the environment wasn't set to EABI.
This change normalizes all target triples and uses the EABI environment
(-eabi in the triple) for Cortex-M targets.
This change also drops the `--target=` flag in the target JSON files,
the flag is now added implicitly in `(*compileopts.Config).CFlags()`.
This removes some duplication in target JSON files.
Unfortunately, this change also increases code size for Cortex-M
targets. It looks like LLVM now emits calls like __aeabi_memmove instead
of memmove, which pull in slightly more code (they basically just call
the regular C functions) and the calls themself don't seem to be as
efficient as they could be. Perhaps this is a LLVM bug that will be
fixed in the future, as this is a very common occurrence.
This is a loose collection of small fixes flagged by staticcheck:
- dead code
- regexp expressions not using backticks (`foobar` / "foobar")
- redundant types of slice and map initializers
- misc other fixes
Not all of these seem very useful to me, but in particular dead code is
nice to fix. I've fixed them all just so that if there are problems,
they aren't hidden in the noise of less useful issues.
Normalization was required because previously we supported Go 1.13 and
Go 1.14 at the same time. Now we've dropped support for both so this
normalization is not necessary anymore.
CGo support remains the same. It's just the test outputs that aren't
normalized anymore.
This patch adds support for passing CFLAGS added in #cgo lines of the
CGo preprocessing phase to the compiler when compiling C files inside
packages. This is expected and convenient but didn't work before.
This commit switches from the previous behavior of compiling the whole
program at once, to compiling every package in parallel and linking the
LLVM bitcode files together for further whole-program optimization.
This is a small performance win, but it has several advantages in the
future:
- There are many more things that can be done per package in parallel,
avoiding the bottleneck at the end of the compiler phase. This
should speed up the compiler futher.
- This change is a necessary step towards a non-LTO build mode for
fast incremental builds that only rebuild the changed package, when
compiler speed is more important than binary size.
- This change refactors the compiler in such a way that it will be
easier to inspect the IR for one package only. Inspecting this IR
will be very helpful for compiler developers.
This makes the result consistent across Go versions, by running a regex
on the CGo output that wraps all single-line functions in a consistent
way.
Originally written by Elliott Sales de Andrade and modified by Ayke van
Laethem.
Since LLVM 9, CGo sometimes randomly breaks with weird error messages on
Windows. I'm not sure why this is the case, but it might be related to
concurrency.
Disable concurrency for now, and hope that will make the errors go away.
This implementation is still very limited but provides a base to build
upon. Limitations:
* CGO_CFLAGS etc is not taken into account.
* These CFLAGS are not used in C files compiled with the package.
* Other flags (CPPFLAGS, LDFAGS, ...) are not yet implemented.
This commit adds tests for CGo preprocessing. There are various errors
that can be reported while preprocessing, and they should integrate well
with the compiler (including accurate source location tracking).
Also allow CGo preprocessing to continue after Clang encountered an
error, for a better view of what happened.
When this flag is set, the testdata/*.out.go files will be updated when
they have changed. This is very convenient for updating these files
after the expected output changes.
Of course, the updated output must still be checked for validity.
