4e62f891cd
Currently, getg is implemented in C, which loads the thread-local g variable. The g variable is declared static in C. This CL exposes the g variable, so it can be accessed from the Go side. This allows the Go compiler to inline getg calls to direct access of g. Currently, the actual inlining is only implemented in the gollvm compiler. The g variable is thread-local and the compiler backend may choose to cache the TLS address in a register or on stack. If a thread switch happens the cache may become invalid. I don't know how to disable the TLS address cache in gccgo, therefore the inlining of getg is not implemented. In the future gccgo may gain this if we know how to do it safely. Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/186238 From-SVN: r273499 |
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.. | ||
config | ||
go | ||
misc/cgo | ||
runtime | ||
testsuite | ||
aclocal.m4 | ||
check-packages.txt | ||
config.h.in | ||
configure | ||
configure.ac | ||
goarch.sh | ||
godeps.sh | ||
gotool-packages.txt | ||
libgo-packages.txt | ||
libgo.imp | ||
LICENSE | ||
Makefile.am | ||
Makefile.in | ||
match.sh | ||
MERGE | ||
merge.sh | ||
mkrsysinfo.sh | ||
mkruntimeinc.sh | ||
mksigtab.sh | ||
mksysinfo.sh | ||
mvifdiff.sh | ||
PATENTS | ||
README | ||
README.gcc | ||
sysinfo.c | ||
VERSION |
See ../README. This is the runtime support library for the Go programming language. This library is intended for use with the Go frontend. This library should not be stripped when it is installed. Go code relies on being able to look up file/line information, which comes from the debugging info using the libbacktrace library. The library has only been tested on GNU/Linux using glibc, and on Solaris. It should not be difficult to port to other operating systems. Directories: go A copy of the Go library from http://golang.org/, with several changes for gccgo. runtime Runtime functions, written in C, which are called directly by the compiler or by the library. Contributing ============ To contribute patches to the files in this directory, please see http://golang.org/doc/gccgo_contribute.html . The master copy of these files is hosted at http://code.google.com/p/gofrontend . Changes to these files require signing a Google contributor license agreement. If you are the copyright holder, you will need to agree to the individual contributor license agreement at http://code.google.com/legal/individual-cla-v1.0.html. This agreement can be completed online. If your organization is the copyright holder, the organization will need to agree to the corporate contributor license agreement at http://code.google.com/legal/corporate-cla-v1.0.html. If the copyright holder for your code has already completed the agreement in connection with another Google open source project, it does not need to be completed again. Debugging ========= This describes how to test libgo when built as part of gccgo. To test a specific package, cd to the libgo build directory (TARGET/libgo) and run `make PKG/check`. For example, `make bytes/check`. To see the exact commands that it runs, including how the compiler is invoked, run `make GOTESTFLAGS=--trace bytes/check`. This will display the commands if the test fails. If the test passes, the commands and other output will be visible in a file named check-testlog in a subdirectory with the name of the package being checked. In the case of bytes/check, this will create bytes/check-testlog. To leave the test program behind, run `make GOTESTFLAGS=--keep bytes/check`. That will leave a gotestNNNN/test directory in the libgo build directory. In that directory you can run `LD_LIBRARY_PATH=../../.libs ./a.out -test.short` to run the tests. You can run specific failing tests using a -test.run option. You can see the tests being run with the -test.v option. You can run the program under a debugger such as gdb.