Compiling with LTO revealed a number of cases in the runtime and
standard library where C and Go disagreed about the type of an object or
function (or where Go and code generated by the compiler disagreed). In
all cases the underlying representation was the same (e.g., uintptr vs.
void*), so this wasn't causing actual problems, but it did result in a
number of annoying warnings when compiling with LTO.
Reviewed-on: https://go-review.googlesource.com/c/160700
From-SVN: r268923
Reviewed-on: https://go-review.googlesource.com/c/158019
gotools/:
* Makefile.am (go_cmd_vet_files): Update for Go1.12beta2 release.
(GOTOOLS_TEST_TIMEOUT): Increase to 600.
(check-runtime): Export LD_LIBRARY_PATH before computing GOARCH
and GOOS.
(check-vet): Copy golang.org/x/tools into check-vet-dir.
* Makefile.in: Regenerate.
gcc/testsuite/:
* go.go-torture/execute/names-1.go: Stop using debug/xcoff, which
is no longer externally visible.
From-SVN: r268084
This CL adds support of precise stack scan using stack maps to
the runtime. The stack maps are generated by the compiler (if
supported). Each safepoint is associated with a (real or dummy)
landing pad, and its "type info" in the exception table is a
pointer to the stack map. When a stack is scanned, the stack map
is found by the stack unwinding code by inspecting the exception
table (LSDA).
For precise stack scan we need to unwind the stack. There are
three cases:
- If a goroutine is scanning its own stack, it can unwind the
stack and scan the frames.
- If a goroutine is scanning another, stopped, goroutine, it
cannot directly unwind the target stack. We handle this by
switching (runtime.gogo) to the target g, letting it unwind
and scan the stack, and switch back.
- If we are scanning a goroutine that is blocked in a syscall,
we send a signal to the target goroutine's thread, and let the
signal handler unwind and scan the stack. Extra care is needed
as this races with enter/exit syscall.
Currently this is only implemented on linux.
Reviewed-on: https://go-review.googlesource.com/c/140518
From-SVN: r266832
Reviewed-on: https://go-review.googlesource.com/136435
gotools/:
* Makefile.am (mostlyclean-local): Run chmod on check-go-dir to
make sure it is writable.
(check-go-tools): Likewise.
(check-vet): Copy internal/objabi to check-vet-dir.
* Makefile.in: Rebuild.
From-SVN: r264546
This is a port of https://golang.org/cl/109596 to the gofrontend, in
preparation for updating libgo to 1.11.
Original CL description:
getcallersp is intrinsified, and so the dummy arg is no longer
needed. Remove it, as well as a few dummy args that are solely
to feed getcallersp.
Reviewed-on: https://go-review.googlesource.com/131116
From-SVN: r263840
Long long long ago Go permitted writing
func F()
in one file and writing
func F() {}
in another file. This was removed from the language, and that is now
considered to be a multiple definition error. Gccgo never caught up
to that, and it has been permitting this invalid code for some time.
Stop permitting it, so that we give correct errors. Since we've
supported it for a long time, the compiler uses it in a couple of
cases: it predeclares the hash/equal methods if it decides to create
them while compiling another function, and it predeclares main.main as
a mechanism for getting the right warning if a program uses the wrong
signature for main. For simplicity, keep those existing uses.
This required a few minor changes in libgo which were relying,
unnecessarily, on the current behavior.
Reviewed-on: https://go-review.googlesource.com/93083
From-SVN: r257600
PR go/84215
runtime, sync/atomic: use write barrier for atomic pointer functions
This copies atomic_pointer.go from 1.10rc2. It was omitted during the
transition of the runtime from C to Go, and I forgot about it.
This may help with https://gcc.gnu.org/PR84215.
Reviewed-on: https://go-review.googlesource.com/93197
From-SVN: r257599
This is in preparation of turning on escape analysis for the
runtime.
- In gccgo, systemstack is implemented with mcall, which is not
go:noescape. Wrap the closure in noescape so the escape analysis
does not think it escapes.
- Mark some C functions go:noescape. They do not leak arguments.
- Use noescape function to make a few local variables' addresses
not escape. The escape analysis cannot figure out because they
are assigned to pointer indirections.
Reviewed-on: https://go-review.googlesource.com/86244
From-SVN: r256418
Update the Go library to the 1.10beta1 release.
Requires a few changes to the compiler for modifications to the map
runtime code, and to handle some nowritebarrier cases in the runtime.
Reviewed-on: https://go-review.googlesource.com/86455
gotools/:
* Makefile.am (go_cmd_vet_files): New variable.
(go_cmd_buildid_files, go_cmd_test2json_files): New variables.
(s-zdefaultcc): Change from constants to functions.
(noinst_PROGRAMS): Add vet, buildid, and test2json.
(cgo$(EXEEXT)): Link against $(LIBGOTOOL).
(vet$(EXEEXT)): New target.
(buildid$(EXEEXT)): New target.
(test2json$(EXEEXT)): New target.
(install-exec-local): Install all $(noinst_PROGRAMS).
(uninstall-local): Uninstasll all $(noinst_PROGRAMS).
(check-go-tool): Depend on $(noinst_PROGRAMS). Copy down
objabi.go.
(check-runtime): Depend on $(noinst_PROGRAMS).
(check-cgo-test, check-carchive-test): Likewise.
(check-vet): New target.
(check): Depend on check-vet. Look at cmd_vet-testlog.
(.PHONY): Add check-vet.
* Makefile.in: Rebuild.
From-SVN: r256365
PR go/81451
runtime: inline runtime_osinit
We had two identical copies of runtime_osinit. They set runtime_ncpu,
a variable that is no longer used. Removing that leaves us with two lines.
Inline those two lines in the two places the function was called.
This fixes GCC PR 81451.
Reviewed-on: https://go-review.googlesource.com/48862
From-SVN: r250326
GCC release freeze.
* go-backend.c: Include "go-c.h".
* go-gcc.cc (Gcc_backend::write_export_data): New method.
* go-gcc.cc (Gcc_backend::Gcc_backend): Declare
__builtin_prefetch.
* Make-lang.in (GO_OBJS): Add go/wb.o.
commit 884c9f2cafb3fc1decaca70f1817ae269e4c6889
Author: Than McIntosh <thanm@google.com>
Date: Mon Jan 23 15:07:07 2017 -0500
compiler: insert additional conversion for type desc ptr expr
Change the method Type::type_descriptor_pointer to apply an additional
type conversion to its result Bexpression, to avoid type clashes in
the back end. The backend expression for a given type descriptor var
is given a type of "_type", however the virtual calls that create the
variable use types derived from _type, hence the need to force a
conversion.
Reviewed-on: https://go-review.googlesource.com/35506
commit 5f0647c71e3b29eddcd0eecc44e7ba44ae7fc8dd
Author: Than McIntosh <thanm@google.com>
Date: Mon Jan 23 15:22:26 2017 -0500
compiler: insure tree integrity in Call_expression::set_result
Depending on the back end, it can be problematic to reuse Bexpressions
(passing the same Bexpression to more than one Backend call to create
additional Bexpressions or Bstatements). The Call_expression::set_result
method was reusing its Bexpression input in more than one tree
context; the fix is to pass in an Expression instead and generate
multiple Bexpression references to it within the method.
Reviewed-on: https://go-review.googlesource.com/35505
commit 7a8e49870885af898c3c790275e513d1764a2828
Author: Ian Lance Taylor <iant@golang.org>
Date: Tue Jan 24 21:19:06 2017 -0800
runtime: copy more of the scheduler from the Go 1.8 runtime
Copies mstart, newm, m0, g0, and friends.
Reviewed-on: https://go-review.googlesource.com/35645
commit 3546e2f002d0277d805ec59c5403bc1d4eda4ed9
Author: Ian Lance Taylor <iant@golang.org>
Date: Thu Jan 26 19:47:37 2017 -0800
runtime: remove a few C functions that are no longer used
Reviewed-on: https://go-review.googlesource.com/35849
commit a71b835254f6d3164a0e6beaf54f2b175d1a6a92
Author: Ian Lance Taylor <iant@golang.org>
Date: Thu Jan 26 16:51:16 2017 -0800
runtime: copy over more of the Go 1.8 scheduler
In particular __go_go (aka newproc) and goexit[01].
Reviewed-on: https://go-review.googlesource.com/35847
commit c3ffff725adbe54d8283c373b6aa7dc95d6fc27f
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Jan 27 16:58:20 2017 -0800
runtime: copy syscall handling from Go 1.8 runtime
Entering a syscall still has to start in C, to save the registers.
Fix entersyscallblock to save them more reliably.
This copies over the tracing code for syscalls, which we previously
weren't doing, and lets us turn on runtime/trace/check.
Reviewed-on: https://go-review.googlesource.com/35912
commit d5b921de4a28b04000fc4c8dac7f529a4a624dfc
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Jan 27 18:34:11 2017 -0800
runtime: copy SIGPROF handling from Go 1.8 runtime
Also copy over Breakpoint.
Fix Func.Name and Func.Entry to not crash on a nil Func.
Reviewed-on: https://go-review.googlesource.com/35913
commit cc60235e55aef14b15c3d2114030245beb3adfef
Author: Than McIntosh <thanm@google.com>
Date: Mon Feb 6 11:12:12 2017 -0500
compiler: convert go_write_export_data to Backend method.
Convert the helper function 'go_write_export_data' into a Backend
class method, to allow for an implementation of this function that
needs to access backend state.
Reviewed-on: https://go-review.googlesource.com/36357
commit e387439bfd24d5e142874b8e68e7039f74c744d7
Author: Than McIntosh <thanm@google.com>
Date: Wed Feb 8 11:13:46 2017 -0500
compiler: insert backend conversion in temporary statement init
Insert an additional type conversion in Temporary_statement::do_get_backend
when assigning a Bexpression initializer to the temporary variable, to
avoid potential clashes in the back end. This can come up when assigning
something of concrete pointer-to-function type to a variable of generic
pointer-to-function type.
Reviewed-on: https://go-review.googlesource.com/36591
commit c5acf0ce09e61ff623847a35a99da465b8571609
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Mar 1 17:57:53 2017 +0100
libgo: build tags for aix
Build tags for the libgo source files required to build
libgo on AIX.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37633
commit 67ed19616898ea18a101ec9325b82d028cd395d9
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 2 15:41:31 2017 +0100
libgo: handle AIX tag in match.sh and gotest
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37638
commit 83ea2d694c10b2dd83fc8620c43da13d20db754e
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Mar 1 17:48:16 2017 +0100
libgo: add AIX support in configure and Makefile
- support for GOOS=aix
- CFLAGS/GOCFLAGS/LDFLAGS for AIX
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37632
commit 35d577fe22ffa16a3ccaadf5dae9f6f425c8ec8c
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Mon Mar 6 15:00:15 2017 +0100
runtime: adapt memory management to AIX mmap
On AIX:
* mmap does not allow to map an already mapped range,
* mmap range start at 0x30000000 for 32 bits processes,
* mmap range start at 0x70000000_00000000 for 64 bits processes
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37845
commit 4e49e56a5fd4072b4ca7fcefe4158d6885d9ee62
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Mon Mar 6 13:42:26 2017 +0100
runtime: add getproccount implementation for AIX
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37844
commit ff626470294237ac664127894826614edc46a3d0
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Mon Mar 6 17:31:21 2017 +0100
runtime: handle ERESTART errno with AIX's wait4
On AIX, wait4 may return with errno set to ERESTART, which causes unexepected
behavior (for instance, go build may exit with the message "wait: restart
system call" after running a command, even if it was successfull).
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37846
commit 37daabbfc83d533b826ef9ab10e2dee7406e7198
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Mon Mar 6 11:02:58 2017 +0100
runtime: support for AIX's procfs tree
On AIX, the process executable file is available under /proc/<pid>/object/a.out
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37842
commit a0275c039d56acf4bf48151978c1a4ec5758cc2c
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Mar 8 07:00:05 2017 -0800
libgo/Makefile.am: don't use nonportable \n or \t in sed expression
The resulting zstdpktlist.go is less pretty, but it works.
Reviewed-on: https://go-review.googlesource.com/37940
commit 29b190f76105aafa2b50b48249afdafecc97a4be
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 9 16:02:34 2017 +0100
runtime: netpoll and semaphores for AIX
semaphore implementation based on Solaris implementation in
libgo/go/runtime/os_solaris.go
netpoll is just a stub to avoid build failure on AIX.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37966
commit 55ca6d3f3cddf0ff9ccb074b2694da9fc54de7ec
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 9 15:38:30 2017 +0100
libmain: ensure initfn is called when loading a go library
AIX does not support .init_array.
The alterative is to export the __go_init function and tell the linker
it is an init function with the -Wl,-binitfini:__go_init option.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37965
commit 349a30d17d880ac8bc1a35e1a2ffee6d6e870ae9
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Fri Mar 10 11:15:08 2017 +0100
libgo: use an import list for missing symbols
libgo depends on symbols provided by Go programs at runtime. On AIX,
this requires either to build libgo with -Wl,-berok linker option and
the programs with -Wl,-brtl, or to provide a list of imported symbols
when building libgo. The second options seems preferable, to avoid
requiring an additional option for every Go program.
There are also some symbols that are specific to GNU ld and do not
exist when linking with AIX ld (__data_start, __edata, __etext and
__bss_start).
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37969
commit 91db0ea1ff068ca1d97b9c99612100ea5b96ddb2
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Mar 8 15:34:45 2017 +0100
crypto/x509: add certificate files locations for AIX
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/37952
commit 92e521c854e91709b949548c47e267377850f26a
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Mar 10 14:10:11 2017 -0800
compiler: fix check for pointer in Temporary_reference_expression
The check for an unrepresentable pointer in
Temporary_reference_expression::do_get_backend was incorrectly
translated from C to Go in https://golang.org/cl/14346043. Fix the
check to use points_to rather than has_pointer and deref. This should
not make any difference in practice as either way the condition will
only be true for a pointer to void, but points_to is correct and more
efficient.
Reviewed-on: https://go-review.googlesource.com/38009
commit 9a0b676e59e7171a630c48fdc3d4de6712bad0ca
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 16 16:51:53 2017 +0100
libgo: add missing _arpcom struct to *sysinfo.go
This struct is filtered due to having a field of type _in6_addr,
but other types exported to *sysinfo.go are depending on it.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38251
commit 61262a757bdd3d9a595ab6a90f68c0c4ebed7bc1
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 16 18:27:46 2017 +0100
syscall: raw_ptrace stub for AIX
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38253
commit 8029632b50880fd9b5e39299c738b38e3386595f
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Mar 15 16:58:37 2017 +0100
libgo: adapt runtime.inc to AIX
* Two AIX types are wrongfully exported to runtime.inc as their names
make them look like a Go type.
* The sigset go type conflicts with a system sigset type.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38192
commit 25f3a90d14bc268479369ecc0eada72791612f86
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Mar 15 16:58:37 2017 +0100
libgo: update Makefile.in, accidentally omitted from last change
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38310
commit d52b4895616b66f93b460366527e74336829aaa5
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 16 18:39:26 2017 +0100
syscall: TIOCSCTTY does not exist on AIX
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38254
commit ff1ec3847a4472008e5d53a98b6694b1e54ca322
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 16 18:07:34 2017 +0100
syscall: syscall does not exist on AIX
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38252
commit c1ee60dabf0b243a0b0286215481a5d326c34596
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Fri Mar 17 17:18:18 2017 +0100
net: EAI_OVERFLOW does not exist on AIX
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38266
commit ad4ad29aed9f70b14b39b488bfeb9ee745382ec4
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Fri Mar 17 17:23:56 2017 +0100
net: sockopt/sockoptip stubs for AIX
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38267
commit 5d7db2d7542fe7082f426d42f8c2ce14aad6df55
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Fri Mar 17 16:35:05 2017 +0100
os/user: add listgroups stub for AIX
This is required to build os/user.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38263
commit 4e57a7973e9fa4cb5ab977c6d792e62a8f7c5795
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Mar 22 11:11:30 2017 +0100
os: fix readdirnames for AIX
Largefile implementation should be used on AIX.
readdir64_r function returns 9 and sets result to NULL when
reaching end of directory, so this return code should not
always be considered as an error.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38359
commit b34036967d1ec57b25e3debe077439b4210a1d4a
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Fri Mar 17 17:39:31 2017 +0100
libgo: adapt sigtab.go to AIX
On AIX, _NSIG is not directly defined to its integer value in
gen-sysinfo.go.
The real value is _SIGMAX32+1 or _SIGMAX64+1, depending if we are
building a 32bit ligbo or a 64bit libgo, so we need to read one of
those constants to set nsig value in mksigtab.sh
This change also ensures that all signal numbers from 0 to nsig-1
are referenced in sigtable.
Reviewed-on: https://go-review.googlesource.com/38268
commit 20991c32671a183ec859b4f285df37fdd4634247
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 23 17:28:09 2017 +0100
syscall: missing import in socket_bsd.go
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38369
commit c34754bd9adf5496c4c26257eaa50793553c11e8
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Mar 22 17:57:01 2017 +0100
sycall: WCOREDUMP macro is not defined on AIX
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38363
commit 4f38813482227b12ea0ac6ac1b981ff9ef9853ef
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 23 17:44:43 2017 +0100
libgo: additional build tags for AIX
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38510
commit d117ede6ff5a7083e9c40eba28a0f94f3535d773
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 23 17:48:46 2017 +0100
go/build: add AIX to "go build" command known OS
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38511
commit 7b0ddaa6a6a71f9eb1c374122d29775b13c2cac5
Author: Ian Lance Taylor <iant@golang.org>
Date: Thu Mar 23 09:57:01 2017 -0700
compiler: don't crash if imported package imports this one
When building a test it's OK if test code imports a package that
imports this one. The go tool is supposed to catch cases where this
creates an impossible initialization order. The compiler already has
code to permit this in Gogo::add_import_init_fn. This CL avoids a
compiler crash on a similar case when writing out the export data.
I have no test case for this. Basically it pushes a compiler crash
into an error reported elsewhere.
Problem was reported by Tony Reix.
Reviewed-on: https://go-review.googlesource.com/38462
commit 925636975d075e3e3353823b09db3f933f23cb03
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Mar 29 14:14:18 2017 -0700
runtime: copy finalizer support from Go 1.8 runtime
Reviewed-on: https://go-review.googlesource.com/38794
commit 1ccb22b96cb3b1011db0e427877d9ddecb577fa9
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Mar 30 15:21:06 2017 +0200
runtime: initcontext and setcontext stubs for AIX
Further investigations are required to understand the clobbering
issue and implement a proper fix. Until then, those stubs are
required to allow the build to complete.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38930
commit 27db481f369b54256063c72b911d22390c59199c
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Mar 29 18:07:25 2017 +0200
os: fix Readlink failure on AIX
AIX readlink routine returns an error if the link is longer
than the buffer, instead of truncating the link.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38700
commit c93babbf48eddd0bc34d4179ffb302dc60087299
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Mar 29 17:26:35 2017 +0200
compiler: implement support for reading AIX big archives
This is required to read go export from a Go library.
Code courtesy of Damien Bergamini from Atos Infogérance.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38698
commit 930dd53482bdee3a9074850d168d0b9d7819c135
Author: Ian Lance Taylor <iant@golang.org>
Date: Thu Apr 6 18:50:11 2017 -0700
compiler: fix whether conversions are static initializers
The compiler was incorrectly treating type conversions from string to
int or vice-versa as static initializers. That doesn't work, as those
conversions are implemented via a function call.
This case may never actually arise but it seems like the right thing to do.
Reviewed-on: https://go-review.googlesource.com/39872
commit f02691e4195728dbf06f4dde0853c6bccc922183
Author: Ian Lance Taylor <iant@golang.org>
Date: Thu Apr 6 17:24:08 2017 -0700
compiler, runtime: don't let slices point past end of memory block
When Go code uses a slice expression like [:len(str)] or [:cap(slice)],
it's natural for the resulting pointer to point just past the end of
the memory block. If the next memory block is not live, we now have a
live pointer to a dead block, which will unnecessarily keep the block
alive. That wastes space, and with the new Go 1.8 GC (not yet
committed) will trigger an error when using GODEBUG=gccheckmark=1.
This changes the implementation of slice expressions to not move the
pointer if the resulting string length or slice capacity is 0. When
the length/capacity is zero, the pointer is never used anyhow.
Reviewed-on: https://go-review.googlesource.com/39870
commit 17527c35b027e1afcc318faf5563909e1e9d44a6
Author: Ian Lance Taylor <iant@golang.org>
Date: Thu Apr 6 15:30:11 2017 -0700
compiler: emit write barriers
The Go 1.8 concurrent GC requires optional write barriers for all
assignments that may change pointer values in the heap or in a global
variable. For details see https://blog.golang.org/go15gc.
This changes the gofrontend code to emit write barriers as needed.
This is in preparation for future changes. At the moment the write
barriers will do nothing. They test runtime.writeBarrier.enabled,
which will never be non-zero. They call simple functions which just
do a move without doing any of the other operations required by the
write barrier.
Reviewed-on: https://go-review.googlesource.com/39852
commit c0b00f072bf34b2c288e1271ec8118b88c4f6f6f
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Tue Apr 11 17:47:29 2017 +0200
libgo: allow building gox files from PIC objects
libtool builds non-PIC objects in the same directory as .lo files
and PIC objects in a .libs subdirectory.
BUILDGOX rule uses the non-PIC objects to build the gox files,
but on AIX only the PIC objects are built.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/40355
commit ea0f3da174c5503a209043f14ddda34871cfec52
Author: Ian Lance Taylor <iant@golang.org>
Date: Thu Apr 6 19:06:14 2017 -0700
compiler: add code to generate a ptrmask for a type
The Go 1.8 garbage collector uses a ptrmask for all types below a
certain size. A ptrmask is simply a bit vector with a single bit for
each pointer-sized word in the value. The bit is 1 if the type has a
pointer in that position, 0 if it does not.
This change adds code to the compiler to generate a ptrmask. The code
is not used by anything yet, it is just compiled. It will be used
when we switch over to the Go 1.8 garbage collector.
The new Array_type::int_length method, and the new memory_size
methods, will also be used by other patches coming later.
Reviewed-on: https://go-review.googlesource.com/39873
commit 3029e1df3be3614d196a03c15e50e68ff850aa4c
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Apr 7 10:31:39 2017 -0700
compiler: add code to generate a gcprog for a type
The Go 1.8 garbage collector uses a gcprog for all types above a
certain size. A gcprog describes where the pointers are in the type,
using a simple bytecode machine that supports repeating bits. The
effect is to permit using much less space to describe arrays. The
format is described in runtime/mbitmap.go in the docs for runGCProg.
This is not yet added to the gofrontend, but can be seen in the gc sources.
This change adds code to the compiler to generate a gcprog. The code
is not used by anything yet, it is just compiled. It will be used
when we switch over to the Go 1.8 garbage collector.
Reviewed-on: https://go-review.googlesource.com/39923
commit 8b01ef1e9176d20f4c9e667972fe031069a4d057
Author: Ian Lance Taylor <iant@golang.org>
Date: Thu Apr 13 07:00:35 2017 -0700
compiler: add ptrdata computations and expressions
For the upcoming Go 1.8 GC we need to compute the "ptrdata" of a type:
the number of bytes in the type that can contain pointers. For types
that do not contain pointers this number is zero. For many types it
is a number larger than zero but smaller than the total size of the
type. The Go 1.8 GC uses this number to make loops looking for
pointers run faster by not scanning the suffix of a value that can not
contain a pointer.
Unfortunately there are two subtly different definitions of ptrdata,
and we need both. The first is the simple one: the prefix that can
contain pointers. The second is the number of bytes described by the
gcprog for the type. Recall that we describe the exact position of
pointers in a type using either a ptrmask or a gcprog. The ptrmask is
simpler, the gcprog uses less space. We use the gcprog for large
types, currently defined as types that are more than 2048 bytes. When
the Go 1.8 runtime expands a gcprog, it verifies that the gcprog
describes exactly the same number of bytes as the ptrdata field in the
type descriptor. If the last pointer-containing portion of a type is
an array, and if the elements of the array have a ptrdata that is less
than the size of the element type, then the simple definition of the
ptrdata will not include the final non-pointer-containing bytes of the
last element of the array. However, the gcprog will define the array
using a repeat count, and will therefore include the full size of the
last element of the array. So for a type that needs a gcprog, the
ptrdata field in the type descriptor must be the size of the data
described by the gcprog, and that is not necessarily the same as the
simple ptrdata.
It might seem that we can always use the gcprog version of the ptrdata
calculation, since that is what will appear in a type descriptor, but
it turns out that for global variables we always use a ptrmask, not a
gcprog, even if the global variable is large. This is because gcprogs
are handled by expanding them into a ptrmask at runtime, and for a
global variable there is no natural place to put the ptrmask. Simpler
to always use the ptrmask. That means that we need to describe the
size of the ptrmask, and that means that we need an expression for the
simple form of the ptrdata.
This CL implements the ptrdata calculation. This code is not actually
used yet. It will be used later when the Go 1.8 GC is committed.
Reviewed-on: https://go-review.googlesource.com/40573
commit 7a37331303b572412179a08141f1dd35339d40c8
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Apr 14 06:55:48 2017 -0700
compiler: zero length arrays never contain pointers
Reviewed-on: https://go-review.googlesource.com/40696
commit c242f0508a64d3d74a28d498cbaeda785ff76258
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Apr 14 07:26:54 2017 -0700
bytes: disable allocations test on gccgo
It turns out that testing.AllocsPerRun has not been producing correct
results with the current gccgo memory allocator. When we update to
the Go 1.8 memory allocator, testing.AllocsPerRun will work again, and
this test will fail due to lack of escape analysis.
Reviewed-on: https://go-review.googlesource.com/40700
commit 0dc369f1d63376a36bfb0999a1b0377fd444bfab
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Tue Apr 11 16:22:38 2017 +0200
os: alternative way to find executable path, using Args[0]
AIX does not provide a proper way to find the original
executable path from procfs, which contains just an
hardlink.
Executable path can be found using Args[0], Getcwd and
$PATH.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/40353
commit f9bad1342569b338e3b2ea9f12ffc6d3d3fa3028
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Apr 14 08:01:19 2017 -0700
compiler: don't write struct with multiple sink fields to C header file
When writing a struct to the C header file used by the C runtime code,
a single sink field is fine: it will be called "_", which is valid C.
There are structs with single sink fields that we want to write out,
such as finblock. As it happens, though, the Go 1.8 runtime has a
struct with two sink fields, gcControllerState, which will produce a C
definition with two fields named "_", which will fail. Since we don't
need to know that struct in C, rather than fix the general case, just
punt if the struct has multiple sink fields.
After the conversion to the Go 1.8 GC, we may be able to get rid of
the C header file anyhow. I'm not sure yet.
Reviewed-on: https://go-review.googlesource.com/40701
commit cfc28901a572aeb15b2f10a38f79eec04c64dfb2
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Apr 14 10:07:23 2017 -0700
runtime: disable allocations test on gccgo
It turns out that testing.AllocsPerRun has not been producing correct
results with the current gccgo memory allocator. When we update to
the Go 1.8 memory allocator, testing.AllocsPerRun will work again, and
these tests will fail due to lack of escape analysis.
Reviewed-on: https://go-review.googlesource.com/40703
commit 36fedd76edaa48b9ec09709a70d9e4abaddf0caf
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Apr 14 10:47:06 2017 -0700
runtime: remove unused size argument from hash/equal fns
The size argument was removed from hash and equal functions in CL
34983. Somehow I missed removing them from three of the predefined
functions.
Reviewed-on: https://go-review.googlesource.com/40770
commit 90f6accb48d2e78cad8955b9292933f6ce3fe4c8
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Apr 14 13:23:05 2017 -0700
runtime: remove unused stack.go
We're never going to use stack.go for gccgo. Although a build tag
keeps it from being built, even having it around can be confusing.
Remove it.
Reviewed-on: https://go-review.googlesource.com/40774
commit befa71603fc66a214e01ac219f2bba36e19f136f
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Apr 14 13:18:34 2017 -0700
runtime: build fastlog
Take out the build tags which were preventing fastlog2 from being
built. It's used by the upcoming Go 1.8 GC.
Reviewed-on: https://go-review.googlesource.com/40773
commit b7e19e9be4ab4c3cd8f4c9506d79a8cd56bace40
Author: Ian Lance Taylor <iant@golang.org>
Date: Fri Apr 14 10:04:23 2017 -0700
runtime: add tests from Go 1.8
Some runtime package tests never made it into the gofrontend repo for
some reason. Add them now.
Reviewed-on: https://go-review.googlesource.com/40869
commit 1feef185aebd71bc2a09b9a04287461806096610
Author: Ian Lance Taylor <iant@golang.org>
Date: Mon Apr 17 16:26:11 2017 -0700
runtime: change mcall to take a Go function value
For future work in bringing in the Go 1.8 GC, change the mcall
function to take a Go function value, which means that mcall can take
a closure rather than just a straight C function pointer.
As part of this change move kickoff from C to Go, which we want to do
anyhow so that we run the write barriers that it generates.
Reviewed-on: https://go-review.googlesource.com/40935
commit c3db34f4efc2d610f74a01dd2ad7775f48889b29
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Tue Apr 11 16:11:26 2017 +0200
runtime: netpoll implementation for AIX
Code courtesy of Damien Bergamini from Atos Infogérance.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/40352
commit f5634dff40e53ad9ce61afd67fd07334e3af9d1f
Author: Ian Lance Taylor <iant@golang.org>
Date: Tue Apr 18 22:06:07 2017 -0700
runtime: move mstart from Go to C
The assignments done in mstart must be done without write barriers, as
mstart is running without an m or p. In the gc toolchain the
equivalent code to intialize g and g->m is written in assembler;
on GNU/Linux, it's in the clone function.
Reviewed-on: https://go-review.googlesource.com/40989
commit 671d7c74592f4b6fe3665af279482ba0ea47ca2d
Author: Ian Lance Taylor <iant@golang.org>
Date: Tue Apr 18 17:47:28 2017 -0700
compiler: varargs slices do not escape in runtime
Also, don't try to allocate an empty slice on the stack, as it will
confuse the GCC backend.
Also add a few trivial style, code formatting, and debug output fixes.
Updates golang/go#17431
Reviewed-on: https://go-review.googlesource.com/40983
commit 94699d25f31353bf03419eda56b15993a39f3275
Author: Ian Lance Taylor <iant@golang.org>
Date: Tue Apr 18 17:30:09 2017 -0700
compiler: add Ptrmask_symbol_expression
Add an expression to evaluate to the ptrmask for a type. This will be
used for global variables, which always use a ptrmask no matter how
large they are.
Reviewed-on: https://go-review.googlesource.com/40981
commit bfff1654eac5b9288fa6c431e66cba8c9da6a660
Author: Ian Lance Taylor <iant@golang.org>
Date: Mon Apr 17 10:51:16 2017 -0700
runtime: change g's in systemstack
The systemstack function in the gc toolchain changes to a different g.
This is often used to get more stack space; the gofrontend uses a
different stack growth mechanism that does not require changing g's,
so we've been running with a version of systemstack that keeps the
same g. However, the garbage collector has various tests to verify
that it is running on g0 rather than on a normal g. For simplicity,
change the gofrontend version of systemstack to change to a different
g just as the gc toolchain does.
This permits us to uncomment some sanity checks in notetsleep.
Doing that requires us to fix up a couple of places where C code calls
{start,stop}TheWorldWithSema while not on g0.
Note that this does slow down some code in the runtime package unnecessarily.
It may be useful to find some places where the runtime calls
systemstack only to get more stack space and change it to use some
other function. That other function would act like systemstack in the
gc toolchain but simply call the argument in the gofrontend.
Reviewed-on: https://go-review.googlesource.com/40973
commit b2ccc7601ce71a7c5732154cf9b2eeea64681469
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 10:36:12 2017 -0700
compiler, runtime: include ptrmask in GC roots
Change the list of registered GC roots to include a ptrmask,
and change the data structures to be easily used from Go code.
The new ptrmask will be used by the Go 1.8 GC to only scan pointers.
Tweak the current GC to use the new structures, but ignore the new
ptrmask information for now.
The new GC root data includes the size of the variable. The size is
not currently used, but will be used later by the cgo checking code.
Reviewed-on: https://go-review.googlesource.com/41075
commit 9e065149970bc180e4ca83bb99c74d9c4f43b47b
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 12:23:16 2017 -0700
compiler, runtime: don't pass size to __go_new
There is no reason to pass the size to __go_new, as the type
descriptor includes the size anyhow. This makes the function
correspond to the Go 1.8 function runtime.newobject, which is what we
will use when we update to the Go 1.8 memory allocator.
Reviewed-on: https://go-review.googlesource.com/41080
commit c321de7b738c4a3387c1842919c9305acfa04c57
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 13:13:56 2017 -0700
compiler, runtime, reflect: make type descriptors more like Go 1.8
Change the type descriptor structure to be more like the one in the Go
1.8 runtime. Specifically we add the ptrdata field, rename the gc
field to gcdata and change the type to *byte, and rearrange a few of
the fields. The structure is still not identical to the Go 1.8
structure--we don't use any of the tricks to reduce overall executable
size--but it is more similar.
For now we don't use the new ptrdata field, and the gcdata field is
still the old format rather than the new Go 1.8 ptrmask/gcprog format.
Reviewed-on: https://go-review.googlesource.com/41081
commit 7b70c52cddeebea9ebeac003f8c6aad59497e5f0
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 14:54:29 2017 -0700
reflect: make sure to clear unusable hash/equal function
Otherwise we wind up copying the one from the prototype, which is wrong.
Also rewrite the hash/equal functions to look like the ones in Go 1.8,
mainly a matter of changing names and using arrayAt.
Reviewed-on: https://go-review.googlesource.com/41133
commit 84d26f467f7de8bdbb0d230458135fe1b6b2a99d
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 14:59:13 2017 -0700
runtime: remove duplicate declarations of SetFinalizer/KeepAlive
These should have been removed in CL 38794. It's a bug that the
compiler even permits these duplicate declarations.
Reviewed-on: https://go-review.googlesource.com/41134
commit f85ff7e64c24031f6d0bd7c9c426b6176cb95160
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 15:56:32 2017 -0700
runtime: don't crash if panicstring called with no m
It's possible for runtime_panicstring to be called with no m if a
signal handler, or scheduler innards, do something wrong. If that
happens carry on with the panic rather than crashing.
Reviewed-on: https://go-review.googlesource.com/41137
commit 5b362b04f642afb8b20715930416fc3b7d91bb12
Author: Than McIntosh <thanm@google.com>
Date: Fri Mar 31 14:35:48 2017 -0400
compiler: fix for expr sharing introduced by Order_eval::statement.
When processing an expression statement with a top-level call
that returns multiple results, Order_eval::statement can wind up
creating a tree that has multiple references to the same call,
which results in a confusing AST dump. Change the implementation
to avoid introducing this unwanted sharing.
Reviewed-on: https://go-review.googlesource.com/39210
commit b05b4260a68695bf9c9cc29e14ae86ca2699458a
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 16:00:28 2017 -0700
runtime: restore correct m in gtraceback
If gtraceback is used to get a stack trace of a g running in the same m,
as can happen if we collect a stack trace from a g0, then restore the
old m value, don't clear it.
Reviewed-on: https://go-review.googlesource.com/41138
commit ca8bbf4dfac19b3f4f7ce21a688b96a418c75031
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 16:03:24 2017 -0700
runtime: set startpc field when starting a new goroutine
This puts the right value in a trace--previously it was always zero.
Reviewed-on: https://go-review.googlesource.com/41139
commit ca8bbf4dfac19b3f4f7ce21a688b96a418c75031
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 16:03:24 2017 -0700
runtime: set startpc field when starting a new goroutine
This puts the right value in a trace--previously it was always zero.
Reviewed-on: https://go-review.googlesource.com/41139
commit 887690dce42d7bf8f711f8ea082e4928fb70f2a5
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 17:06:11 2017 -0700
runtime: add prefetch functions
The Go 1.8 GC uses prefetch functions. Add versions for gccgo that
call __builtin_prefetch. Uncomment the test for them in testAtomic64.
Don't force the check function to return early, as now taking the
address of a local variable in the runtime package does not force it
onto the heap.
Reviewed-on: https://go-review.googlesource.com/41144
commit 4269db69f9184e5a45c54aaee7352425a1f88bff
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 17:55:21 2017 -0700
runtime: split up ticks to get correct alignment
On 32-bit x86 a uint64 variable by itself is aligned to an 8-byte boundary.
A uint64 field in a struct is aligned to a 4-byte boundary.
The runtime.ticks variable has a uint64 field that must be aligned
to an 8-byte boundary. Rather than rely on luck, split up the struct
into separate vars so that the required alignment happens reliably.
It would be much nicer if issue golang/go#19057 were fixed somehow,
but that is for another day.
Reviewed-on: https://go-review.googlesource.com/41143
commit 66926cabdbdbf3431b4f172f7756e195c1c6c513
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Apr 20 17:15:38 2017 +0200
libgo: fix bad value for O_CLOEXEC on AIX 7.1
On AIX 7.1, O_CLOEXEC is defined as 0x0000001000000000, which
creates an integer constant overflow error when building libgo.
This affects only 7.1, O_CLOEXEC is not defined on 6.1 (and
defaults to O in sysinfo.go) and is defined as 0x00800000 on
AIX 7.2.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/41214
commit af288ff10aeafc47651f5def327ed56425d5be19
Author: Ian Lance Taylor <iant@golang.org>
Date: Thu Apr 20 17:15:02 2017 -0700
runtime: preserve stack context in tracebackothers
The tracebackothers function works by saving the current stack context
in the goroutine's context field and then calling gogo to switch to a
new goroutine. The new goroutine will collect its own stack trace and
then call gogo to switch back to the original goroutine. This works
fine, but if the original goroutine was called by mcall then the
contents of its context field are needed to return from the mcall.
Fix this by saving the stack context across the calls to the other
goroutines.
Reviewed-on: https://go-review.googlesource.com/41293
commit 43101e5956e793f1b4de05c15d7738c785e927df
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Fri Apr 21 10:58:52 2017 +0200
os/user: use _posix_* libc functions
libc getpwnam_r function has a different signature, we must use
_posix_getpwnam_r instead (by default, the pwd.h system include
file defines getpwnam_r as a static function calling
_posix_getpwnam_r, so a C program calling getpwnam_r will indeed
reference the _posix_getpwnam_r symbol).
Idem for getpwuid_r, getgrnam_r and getgrgid_r.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/41334
commit 71e1fec4d2a536591ea6657a06916a17b5127071
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Apr 19 21:24:48 2017 -0700
runtime: don't use pointers in g_ucontext_t or stackcontext
The g_ucontext_t type holds registers saved for a goroutine. We have
to scan it for pointers, but since registers don't necessarily hold
pointers we have to scan it conservatively. That means that it should
not have a pointer type, since the GC will always scan pointers.
Instead it needs special treatment to be scanned conservatively.
The current GC doesn't care when a pointer type holds a non-pointer,
but the Go 1.8 GC does.
For the current GC this means we have to explicitly scan the
g_ucontext_t values in a G.
While we're at it change stackcontext to be uintptr too. The entries
in stackcontext never hold pointers that the Go GC cares about.
Reviewed-on: https://go-review.googlesource.com/41270
commit eab2960aee91d3e3a6baa5b1bce01262d24c714f
Author: Ian Lance Taylor <iant@golang.org>
Date: Thu Apr 20 17:08:19 2017 -0700
runtime/internal/sys: define Goexperiment
The gc toolchain defines Goexperiment based on the environment
variable GOEXPERIMENT when the toolchain is built. We just always set
Goexperiment to the empty string.
Reviewed-on: https://go-review.googlesource.com/41292
commit be4a751943265c0637da859d15a4faf162f5c478
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Thu Apr 20 14:04:35 2017 +0200
net: sockopt implementation for AIX
This is a copy of the Linux implementation, it allows to
run some simple client/server applications on AIX, while
the current sockopt stubs don't.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/41213
commit 46a669c4ca5b80fd6f6a0a42095804d9f704611d
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Mar 29 17:55:06 2017 +0200
math: fix sign for atan/expm1/log1p(-0)
AIX libc returns +0 for atan(-0), expm1(-0) and log1p(-0),
while matching Go functions must return -0.
Code courtesy of Tony Reix.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/38699
commit 53b0e809130038a46f0a3d2870e3905f44ab888d
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Apr 26 17:29:22 2017 +0200
runtime: fix context clobbering on AIX
On AIX 64-bits, r13 is a pointer to thread data.
setcontext() overwrites r13 with the value saved by getcontext().
So, when a goroutine is scheduled on a new thread, r13 will point
to the old thread data after calling setcontext().
Code courtesy of Damien Bergamini.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/41854
commit f8d5ebd71c71e6e777200530d8204b92619157f8
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Wed Apr 26 18:01:19 2017 +0200
runtime: fix wrong time calculation in semasleep
tv_nsec is added twice when calculating the sleep end time.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/41855
commit ef56097f4ea848d48fbf61eba1c757fe7fce99d3
Author: Matthieu Sarter <matthieu.sarter.external@atos.net>
Date: Fri Apr 28 10:27:32 2017 +0200
libgo: pass $(NM) value when running benchmarks
On AIX, we need to use "nm -B" instead of "nm", to have the
epxected output format, so the configured $(NM) value from
the Makefile should be exported before running gotest, which
defaults to "nm" if $NM is not set.
Issue golang/go#19200
Reviewed-on: https://go-review.googlesource.com/42051
commit 0fb550083ae474fb964435927b899ec8e4b62771
Author: Ian Lance Taylor <iant@golang.org>
Date: Wed Nov 16 21:12:53 2016 -0800
runtime: copy garbage collector from Go 1.8 runtime
This giant patch replaces the old Go 1.4 memory allocator and garbage
collector with the new Go 1.8 code. The memory allocator is fairly
similar, though now written in Go rather than C. The garbage
collector is completely different. It now uses ptrmask and gcprog
information, which requires changes in the compiler and the reflect
package as well as the runtime. And, of course, the garbage collector
now runs concurrently with program execution.
In the gc toolchain the garbage collector is strict and precise at all
levels. In the gofrontend we do not have stack maps, so stacks, and
register values, are collected conservatively. That means that an
old, no longer used, pointer on a stack or in a register can cause a
memory object to live longer than it should. That in turns means that
we must disable some checks for invalid pointers in the garbage
collection code. Not only can we get an invalid pointer on the stack;
the concurrent nature of the collector means that we can in effect
resurrect a block that was already unmarked but that the collector had
not yet gotten around to freeing, and that block can in turn point to
other blocks that the collector had managed to already free. So we
must disable pointer checks in general. In effect we are relying on
the fact that the strict pointer checks in the gc toolchain ensure
that the garbage collector is correct, and we just assume that it is
correct for the gofrontend since we are using the same code.
Reviewed-on: https://go-review.googlesource.com/41307
commit a95078d501175240d095500a8c5fbfb21bec65cb
Author: Ian Lance Taylor <iant@golang.org>
Date: Mon Apr 24 16:33:47 2017 -0700
libgo/Makefile: clean more files
Fix up the mostlyclean, clean, and distclean targets to better follow
https://www.gnu.org/prep/standards/html_node/Standard-Targets.html.
Reviewed-on: https://go-review.googlesource.com/41625
commit 5956bf1055451cf4239cdfeca259c23b1ded54d8
Author: Ian Lance Taylor <iant@golang.org>
Date: Mon May 8 13:35:11 2017 -0700
libgo: delete goc2c
The last .goc file has been removed, so remove goc2c.
The goc2c program was my first contribution to the gc repository that
was more than 100 lines:
2b57a1124e
The program was used in gc for a few years under various guises but
was finally removed in https://golang.org/cl/132680043. Now we can
remove it from gofrontend as well.
Reviewed-on: https://go-review.googlesource.com/42911
commit a222e35d041de0cd42506b61c93b8209e07702b9
Author: Than McIntosh <thanm@google.com>
Date: Tue May 9 10:33:10 2017 -0400
compiler: set "need_init_fn" when adding gc root
Variables that back slice initializers in certain cases have to be
added to the gc roots list, since they can be modified at runtime. The
code that was doing this addition did not update the flag that tracks
whether the package being compiled needs an initializer function,
which resulted in the call in question being left out of the final
generated code in certain cases. Fix is to change Gogo::add_gc_root()
to update the "needs init" flag.
Reviewed-on: https://go-review.googlesource.com/43030
commit 822ab419bf7d1c705cdce1c12133e7a11f56be2e
Author: Than McIntosh <thanm@google.com>
Date: Tue May 9 11:36:51 2017 -0400
compiler: fix variable context nit in write barrier generation
Update the write barrier generation code to insure that the "lvalue
context" tag on the space var expression is set only in the case where
the expr feeds directly into an assignment. This is somewhat
counter-intuitive, but needed in the case where the backend looks at
context tags.
Reviewed-on: https://go-review.googlesource.com/43031
From-SVN: r247848
Since the name siginfo winds up in runtime.inc, this avoids a name
collision on systems that define "struct siginfo" in the system header
files.
Reviewed-on: https://go-review.googlesource.com/35239
From-SVN: r244484
Compiler changes:
* Change map assignment to use mapassign and assign value directly.
* Change string iteration to use decoderune, faster for ASCII strings.
* Change makeslice to take int, and use makeslice64 for larger values.
* Add new noverflow field to hmap struct used for maps.
Unresolved problems, to be fixed later:
* Commented out test in go/types/sizes_test.go that doesn't compile.
* Commented out reflect.TestStructOf test for padding after zero-sized field.
Reviewed-on: https://go-review.googlesource.com/35231
gotools/:
Updates for Go 1.8rc1.
* Makefile.am (go_cmd_go_files): Add bug.go.
(s-zdefaultcc): Write defaultPkgConfig.
* Makefile.in: Rebuild.
From-SVN: r244456
I looked at a diff of proc.go between Go 1.7 and gccgo, and copied
over all the easy stuff.
Reviewed-on: https://go-review.googlesource.com/35090
From-SVN: r244291
This started by moving procresize from C to Go so that we can pass the
right type to the memory allocator when allocating a p, which forced
the gomaxprocs variable to move from C to Go, and everything else
followed from that.
Reviewed-on: https://go-review.googlesource.com/34916
From-SVN: r244236
PR go/78789
runtime: don't build aeshash.c if the assembler doesn't support it
This is for CentOS 5, whose assembler does not know the aesinc
instruction.
Fixes GCC PR 78789.
Patch by Uros Bizjak.
Reviewed-on: https://go-review.googlesource.com/34796
From-SVN: r244031
Remove support for _cgo_allocate. It was removed from the gc
toolchain in Go 1.5, so it is unlikely that anybody is trying to use it.
Reviewed-on: https://go-review.googlesource.com/34557
From-SVN: r243805
Rewrite the AES hashing code from gc assembler to C code using
intrinsics. The resulting code generates the same hash code for the
same input as the gc code--that doesn't matter as such, but testing it
ensures that the C code does something useful.
Also change mips64pe32le to mips64p32le in configure script--noticed
during CL review.
Reviewed-on: https://go-review.googlesource.com/34022
From-SVN: r243445
With -buildmode=c-archive, initsig is called before the memory
allocator has been initialized. The code was doing a memory
allocation because of the call to funcPC(sigtramp). When escape
analysis is fully implemented, that call should not allocate. For
now, finesse the issue by calling a C function to get the C function
pointer value of sigtramp.
When returning from a call from C to a Go function, a deferred
function is run to go back to syscall mode. When the call occurs on a
non-Go thread, that call sets g to nil, making it impossible to add
the _defer struct back to the pool. Just drop it and let the garbage
collector clean it up.
Reviewed-on: https://go-review.googlesource.com/33675
From-SVN: r242992
The actual stack unwind code is still in C, but the rest of the code,
notably all the memory allocation, is now in Go. The names are changed
to the names used in the Go 1.7 runtime, but the code is necessarily
somewhat different.
The __go_makefunc_can_recover function is dropped, as the uses of it
were removed in https://golang.org/cl/198770044.
Reviewed-on: https://go-review.googlesource.com/33414
From-SVN: r242715
This doesn't change any actual code, it just starts using the Go
definition of the schedt type and the sched variable rather than the C
definitions.
The schedt type is tweaked slightly for gccgo. We aren't going to
release goroutine stacks, so we don't need separate gfreeStack and
gfreeNostack lists. We only have one size of defer function, so we
don't need a list of 5 different pools.
Reviewed-on: https://go-review.googlesource.com/33364
From-SVN: r242600
A step toward eliminating goc2c.
Drop the exported parfor code; it was needed for tests in the past, but
no longer is. The Go 1.7 runtime no longer uses parfor.
Reviewed-on: https://go-review.googlesource.com/33324
From-SVN: r242509
Add a little shell script to auto-generate runtime.sigtable from the
known signal names.
Force the main package to always import the runtime package. Otherwise
some runtime package global variables may never be initialized.
Set the syscallsp and syscallpc fields of g when entering a syscall, so
that the runtime package knows when a g is executing a syscall.
Fix runtime.funcPC to avoid dead store elimination of the interface
value when the function is inlined.
Reviewed-on: https://go-review.googlesource.com/33025
From-SVN: r242060
Change the compiler handle append as the gc compiler does: call a
function to grow the slice, but otherwise assign the new elements
directly to the final slice.
For the current gccgo memory allocator the slice code has to call
runtime_newarray, not mallocgc directly, so that the allocator sets the
TypeInfo_Array bit in the type pointer.
Rename the static function cnew to runtime_docnew, so that the stack
trace ignores it when ignoring runtime functions. This was needed to
fix the runtime/pprof tests on 386.
Reviewed-on: https://go-review.googlesource.com/32218
From-SVN: r241667
I started to copy the Go 1.7 interface code, but the gc and gccgo
representations of interfaces are too different. So instead I rewrote
the gccgo interface code from C to Go. The code is largely the same as
it was, but the names are more like those used in the gc runtime.
I also copied over the string comparison functions, and tweaked the
compiler to use eqstring when comparing strings for equality.
Reviewed-on: https://go-review.googlesource.com/31591
From-SVN: r241384
While we're at it, update the runtime/debug package, and start running
its testsuite by default. I'm not sure why runtime/debug was not
previously updated to 1.7. Doing that led me to fix some minor aspects
of runtime.Stack and the C function runtime/debug.readGCStats.
Reviewed-on: https://go-review.googlesource.com/31251
From-SVN: r241261
Fix handling of function values for -fgo-c-header to generate FuncVal*,
not simply FuncVal.
While we're here change runtime.nanotime to use clock_gettime with
CLOCK_MONOTONIC, rather than gettimeofday. This is what the gc library
does. It provides nanosecond precision and a monotonic clock.
Reviewed-on: https://go-review.googlesource.com/31232
From-SVN: r241197
Also create a gccgo version of some of the traceback code in
traceback_gccgo.go, replacing some code currently in C.
This required modifying the compiler so that when compiling the runtime
package a slice expression does not cause a local array variable to
escape to the heap.
Reviewed-on: https://go-review.googlesource.com/31230
From-SVN: r241189
This replaces runtime/cpuprof.goc with go/runtime/cpuprof.go and adjusts
the supporting code in runtime/proc.c.
This adds another case where the compiler needs to avoid heap allocation
in the runtime package: when evaluating a method expression into a
closure. Implementing this required moving the relevant code from
do_get_backend to do_flatten, so that I could easily add a temporary
variable. Doing that let me get rid of Bound_method_expression::do_lower.
Reviewed-on: https://go-review.googlesource.com/31050
From-SVN: r241163
This replaces mem.go and the C runtime_ReadMemStats function with the Go
1.7 mstats.go.
The GCStats code is commented out for now. The corresponding gccgo code
is in runtime/mgc0.c.
The variables memstats and worldsema are shared between the Go code and
the C code, but are not exported. To make this work, add temporary
accessor functions acquireWorldsema, releaseWorldsema, getMstats (the
latter known as mstats in the C code).
Check the preemptoff field of m when allocating and when considering
whether to start a GC. This works with the new stopTheWorld and
startTheWorld functions in Go, which are essentially the Go 1.7
versions.
Change the compiler to stack allocate closures when compiling the
runtime package. Within the runtime packages closures do not escape.
This is similar to what the gc compiler does, except that the gc
compiler, when compiling the runtime package, gives an error if escape
analysis shows that a closure does escape. I added this here because
the Go version of ReadMemStats calls systemstack with a closure, and
having that allocate memory was causing some tests that measure memory
allocations to fail.
Reviewed-on: https://go-review.googlesource.com/30972
From-SVN: r241124
Add compiler support for turning concatenating strings into a call to
a runtime function that takes the appropriate number of arguments.
Rename some local variables in mgc0.c to avoid macros that the new
rune.go causes to appear in runtime.inc.
Reviewed-on: https://go-review.googlesource.com/30827
From-SVN: r241074
Update the compiler to use the new names. Add calls to printlock and
printunlock around print statements. Move expression evaluation before
the call to printlock. Update g's writebuf field to a slice, and adjust
C code accordingly.
Reviewed-on: https://go-review.googlesource.com/30717
From-SVN: r240956
Change the compiler to use the new routines. Drop the separation of
small and large values when sending on a channel. Allocate the select
struct on the stack. Remove the old C implementation of channels. Adjust
the garbage collector for the new data structure.
Bring in part of the tracing code, enough for the channel code to call.
Bump the permitted number of allocations in one of the tests in
context_test.go. The difference is that now receiving from a channel
allocates a sudog, which the C code used to simply put on the
stack. This will be somewhat better when we port proc.go.
Reviewed-on: https://go-review.googlesource.com/30714
From-SVN: r240941
Remove the old locking code written in C.
Add a shell script mkrsysinfo.sh to generate the runtime_sysinfo.go
file, so that we can get Go copies of the system time structures and
other types.
Tweak the compiler so that when compiling the runtime package the
address operator does not cause local variables to escape. When the gc
compiler compiles the runtime, an escaping local variable is treated as
an error. We should implement that, instead of this change, when escape
analysis is turned on.
Tweak the compiler so that the generated C header does not include names
that start with an underscore followed by a non-upper-case letter,
except for the special cases of _defer and _panic. Otherwise we
translate C types to Go in runtime_sysinfo.go and then generate those Go
types back as C types in runtime.inc, which is useless and painful for
the C code.
Change entersyscall and friends to take a dummy argument, as the gc
versions do, to simplify calls from the shared code.
Reviewed-on: https://go-review.googlesource.com/30079
From-SVN: r240657
Also copy over cputicks.go, env_posix.go, vdso_none.go, stubs2.go, and a
part of os_linux.go. Remove the corresponding functions from the C code
in libgo/go/runtime. Add some transitional support functions to
stubs.go. This converts several minor functions from C to Go.
Reviewed-on: https://go-review.googlesource.com/29962
From-SVN: r240609
This change removes the gccgo-specific hashmap code and replaces it with
the hashmap code from the Go 1.7 runtime. The Go 1.7 hashmap code is
more efficient, does a better job on details like when to update a key,
and provides some support against denial-of-service attacks.
The compiler is changed to call the new hashmap functions instead of the
old ones.
The compiler now tracks which types are reflexive and which require
updating when used as a map key, and records the information in map type
descriptors.
Map_index_expression is simplified. The special case for a map index on
the right hand side of a tuple expression has been unnecessary for some
time, and is removed. The support for specially marking a map index as
an lvalue is removed, in favor of lowering an assignment to a map index
into a function call. The long-obsolete support for a map index of a
pointer to a map is removed.
The __go_new_map_big function (known to the compiler as
Runtime::MAKEMAPBIG) is no longer needed, as the new runtime.makemap
function takes an int64 hint argument.
The old map descriptor type and supporting expression is removed.
The compiler was still supporting the long-obsolete syntax `m[k] = 0,
false` to delete a value from a map. That is now removed, requiring a
change to one of the gccgo-specific tests.
The builtin len function applied to a map or channel p is now compiled
as `p == nil ? 0 : *(*int)(p)`. The __go_chan_len function (known to
the compiler as Runtime::CHAN_LEN) is removed.
Support for a shared zero value for maps to large value types is
introduced, along the lines of the gc compiler. The zero value is
handled as a common variable.
The hash function is changed to take a seed argument, changing the
runtime hash functions and the compiler-generated hash functions.
Unlike the gc compiler, both the hash and equal functions continue to
take the type length.
Types that can not be compared now store nil for the hash and equal
functions, rather than pointing to functions that throw. Interface hash
and comparison functions now check explicitly for nil. This matches the
gc compiler and permits a simple implementation for ismapkey.
The compiler is changed to permit marking struct and array types as
incomparable, meaning that they have no hash or equal function. We use
this for thunk types, removing the existing special code to avoid
generating hash/equal functions for them.
The C runtime code adds memclr, memequal, and memmove functions.
The hashmap code uses go:linkname comments to make the functions
visible, as otherwise the compiler would discard them.
The hashmap code comments out the unused reference to the address of the
first parameter in the race code, as otherwise the compiler thinks that
the parameter escapes and copies it onto the heap. This is probably not
needed when we enable escape analysis.
Several runtime map tests that ere previously skipped for gccgo are now
run.
The Go runtime picks up type kind information and stubs. The type kind
information causes the generated runtime header file to define some
constants, including `empty`, and the C code is adjusted accordingly.
A Go-callable version of runtime.throw, that takes a Go string, is
added to be called from the hashmap code.
Reviewed-on: https://go-review.googlesource.com/29447
* go.go-torture/execute/map-1.go: Replace old map deletion syntax
with call to builtin delete function.
From-SVN: r240334
This upgrades all of libgo other than the runtime package to
the Go 1.4 release. In Go 1.4 much of the runtime was
rewritten into Go. Merging that code will take more time and
will not change the API, so I'm putting it off for now.
There are a few runtime changes anyhow, to accomodate other
packages that rely on minor modifications to the runtime
support.
The compiler changes slightly to add a one-bit flag to each
type descriptor kind that is stored directly in an interface,
which for gccgo is currently only pointer types. Another
one-bit flag (gcprog) is reserved because it is used by the gc
compiler, but gccgo does not currently use it.
There is another error check in the compiler since I ran
across it during testing.
gotools/:
* Makefile.am (go_cmd_go_files): Sort entries. Add generate.go.
* Makefile.in: Rebuild.
From-SVN: r219627
Ian Lance Taylor
Ian Lance Taylor
Ian Lance Taylor