GCC has supported the __atomic intrinsics since 4.7. They are better
than the __sync intrinsics in that they specify a memory model and,
more importantly for our purposes, they are reliably implemented
either in the compiler or in libatomic.
Fixes https://gcc.gnu.org/PR52084
Reviewed-on: https://go-review.googlesource.com/c/160820
From-SVN: r268458
If sigtramp and sigtrampgo are both on stack, n -= framesToDiscard
is executed twice, which should actually run only once.
Reviewed-on: https://go-review.googlesource.com/c/159238
From-SVN: r268366
If a panic happens in the runtime we turn that into a fatal error.
We use the caller's PC to determine if the panic call is inside
the runtime. getcallerpc returns the PC immediately after the
call instruction. If the call is the very last instruction of a
function, it may not find this PC belong to a runtime function,
giving false result. We need to back off the PC by 1 to the call
instruction.
The gc runtime doesn't do this because the gc compiler always
emit an instruction following a panic call, presumably an UNDEF
instruction which turns into an architecture-specific illegal
instruction. Our compiler doesn't do this.
Reviewed-on: https://go-review.googlesource.com/c/159437
From-SVN: r268358
Precise stack scan uses SIGURG to trigger a stack scan. We need
to have Go signal handler installed for SIGURG.
Reviewed-on: https://go-review.googlesource.com/c/159097
From-SVN: r268230
For the gofrontend copy, change calls to types.SizesFor to pass
"gccgo" rather than "gc". Leave the asmdecl pass unchanged since that
pass is gc-specific anyhow.
This has been fixed in a better way in the external repo by
https://golang.org/cl/158317 and friends, but that is not in 1.12, so
use this approach for now.
Reviewed-on: https://go-review.googlesource.com/c/158842
From-SVN: r268153
PR go/88927
runtime, internal/cpu: fix build for ARM GNU/Linux
Was failing with
../../../libgo/go/internal/cpu/cpu.go:138:2: error: reference to undefined name 'doinit'
138 | doinit()
| ^
Fix it by adding in Go 1.12 internal/cpu/cpu_arm.go, and the code in
runtime that initializes the values.
Fixes https://gcc.gnu.org/PR88927.
Reviewed-on: https://go-review.googlesource.com/c/158717
From-SVN: r268131
Restore some of the fixes that were applied to golang_org/x/net/lif
but were lost when 1.12 moved the directory to internal/x/net/lif.
Add support for reading /proc to fetch argc/argv/env for c-archive mode.
Reviewed-on: https://go-review.googlesource.com/c/158640
From-SVN: r268130
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
Currently, we dropg (which clears gp.m) after we CAS the g status
to _Grunnable or _Gwaiting. Immediately after CASing the g status,
another thread may CAS it to _Gscan status and scan its stack.
With precise stack scan, it accesses gp.m in order to switch to g
and back (in doscanstackswitch). This races with dropg. If
doscanstackswitch reads gp.m, then dropg runs, when we restore
the m at the end of the scan it will set to a stale value. Worse,
if dropg runs after doscanstackswitch sets the new m, gp will be
running with a nil m.
To fix this, we do dropg before CAS g status to _Grunnable or
_Gwaiting. We can do this safely if we are CASing from _Grunning,
as we own the g when it is in _Grunning. There is one case where
we CAS from _Gsyscall to _Grunnable. It is not safe to dropg when
it is in _Gsyscall, as precise stack scan needs to read gp.m in
order to signal the m. So we need to introduce a transient state,
_Gexitingsyscall, between _Gsyscall and _Grunnable, where the GC
should not scan its stack.
In is a little unfortunate that we have to add another g status.
We could reuse an existing one (e.g. _Gcopystack), but it is
clearer and safer to just use a new one, as Austin suggested.
Reviewed-on: https://go-review.googlesource.com/c/158157
From-SVN: r268001
Many C syscall functions take pointer arguments. The pointers
don't escape in the C functions. Mark the C functions noescape so
calling them doesn't need allocation.
Reviewed-on: https://go-review.googlesource.com/c/158158
From-SVN: r267989
CL 157557 changes the compiler to add one byte padding to
non-empty struct ending with a zero-sized field. Add the same
padding to the FFI type, so reflect.Call works.
This fixes test/fixedbugs/issue26335.go in the main repo.
Reviewed-on: https://go-review.googlesource.com/c/158018
From-SVN: r267956
This ports https://golang.org/cl/155918 from the master repo.
runtime: panic on uncomparable map key, even if map is empty
Reorg map flags a bit so we don't need any extra space for the extra flag.
This is a pre-req for updating libgo to the Go 1.12beta2 release.
Reviewed-on: https://go-review.googlesource.com/c/157858
From-SVN: r267950
This is following CL 156038. doscanstackswitch uses the same
mechanism of switching goroutines as getTraceback, and so has
the same problem as described in issue golang/go#29448. This CL
applies the same fix.
Reviewed-on: https://go-review.googlesource.com/c/156697
From-SVN: r267661
This is the gccgo version of https://golang.org/cl/141822:
Only return a pointer p to the new slices backing array from makeslice.
Makeslice callers then construct sliceheader{p, len, cap} explictly
instead of makeslice returning the slice.
This change caused the GCC backend to break the runtime/pprof test by
merging together the identical functions allocateReflectTransient and
allocateTransient2M. This caused the traceback to be other than
expected. Fix that by making the functions not identical.
This is a step toward updating libgo to the Go1.12beta1 release.
Reviewed-on: https://go-review.googlesource.com/c/155937
From-SVN: r267660
Currently, when collecting a traceback for another goroutine,
getTraceback calls gogo(gp) switching to gp, which will resume in
mcall, which will call gtraceback, which will set up gp->m. There
is a gap between setting the current running g to gp and setting
gp->m. If a profiling signal arrives in between, sigtramp will
see a non-nil gp with a nil m, and will seg fault. Fix this by
setting up gp->m first.
Fixesgolang/go#29448.
Reviewed-on: https://go-review.googlesource.com/c/156038
From-SVN: r267658
Traceback routines, e.g. callers and funcentry, may call
__go_get_backtrace_state. If a profiling signal arrives while we
are in the critical section of __go_get_backtrace_state, it tries
to do a traceback, which also calls __go_get_backtrace_state,
which tries to enter the same critical section and will deadlock.
Prevent this deadlock by setting up runtime_in_callers before
calling __go_get_backtrace_state.
Found while investigating golang/go#29448. Will add a test in the
next CL.
Updates golang/go#29448.
Reviewed-on: https://go-review.googlesource.com/c/156037
From-SVN: r267590
Precise stack scan needs to unwind the stack. When it is
unwinding the stack, if a profiling signal arrives, which also
does a traceback, it may deadlock in dl_iterate_phdr. Prevent
this deadlock by setting up runtime_in_callers before traceback.
Reviewed-on: https://go-review.googlesource.com/c/155766
From-SVN: r267457
On ARM32 EABI, unlike other platforms, the personality function is
called during _Unwind_Backtrace (libgcc/unwind-arm-common.inc:581).
In this case, simply unwind the frame without returning any
handlers. Otherwise traceback will loop if there is a frame with
a defer on stack.
Reviewed-on: https://go-review.googlesource.com/c/155759
From-SVN: r267434
On ARM32 EABI, when the "compact" unwinding model is used, it
does not have standard LSDA and _Unwind_GetLanguageSpecificData
will not return data that is parseable by us. Check this
conditon before calling _Unwind_GetLanguageSpecificData.
Fix ARM32 build.
Reviewed-on: https://go-review.googlesource.com/c/155758
From-SVN: r267428
The type table encoding can be DW_EH_PE_absptr, but this case
was missing, which was causing abort on ARM32 EABI. Add the
missing case.
Reviewed-on: https://go-review.googlesource.com/c/153857
From-SVN: r267070
This increases the time to wait for signals to be delivered in the
TestAtomicStop testcase. When running gccgo tests on ppc64 or ppc64le,
there are intermittent failures in this test because the wait time is
too small.
Updates golang/go#29046
Reviewed-on: https://go-review.googlesource.com/c/153879
From-SVN: r267068
ARM32 EABI unwinder does not define _URC_NORMAL_STOP. Instead,
it has _URC_FAILURE. Use _URC_FAILURE there.
Should fix ARM32 build.
Reviewed-on: https://go-review.googlesource.com/c/153417
From-SVN: r267033
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
In buildmodeinit, the c-archive buildmode is flagged as invalid
on linux/ppc64 for gccgo when it should be valid. This happens
because the check against the gccgo flag is done after the checks
for valid GOOS/GOARCH pairs instead of before as is done for all
other buildmode cases in this switch. This corrects the problem and
allows several of the gccgo gotools testcases to pass on linux/ppc64.
Updates #29046
Reviewed-on: https://go-review.googlesource.com/c/152137
From-SVN: r266764
For inlined function bodies we're going to need to refer to variables,
so change the existing export data to add a '$' to names that look
like identifiers: true, false, nil, convert.
While we're here drop an unnecessary space character after operators.
Reviewed-on: https://go-review.googlesource.com/c/150067
From-SVN: r266529
Create a framework for putting function bodies in export data. At
present only empty functions will be put there, and they will be
ignored on import. Later patches will get this to the point of
supporting inlining of (some) functions defined in other packages.
Reviewed-on: https://go-review.googlesource.com/c/150061
From-SVN: r266490
PR go/88060
syscall: always define _AT_FDCWD and IPv6MTUInfo
They aren't defined by old versions of glibc, but are required by the
code in syscall_linux.go.
Reviewed-on: https://go-review.googlesource.com/c/150697
From-SVN: r266333
The code to implement new-style gccgo name mangling had a recipe that
didn't quite match the one in the compiler (incorrect handling for
'.'). This showed up as a failure in the gotools cgo test if the
directory containing the test run included a "." character.
Reviewed-on: https://go-review.googlesource.com/c/147917
From-SVN: r265981
PR bootstrap/82856
libgo: update to autoconf 2.69 and automake 1.15.1
Initial patch from Joseph Myers.
Reviewed-on: https://go-review.googlesource.com/c/146417
From-SVN: r265701
Fix asm name directive for the C version of log/syslog.syslog_c,
which didn't get included in the recent name mangling change.
Reviewed-on: https://go-review.googlesource.com/c/145017
From-SVN: r265533
The current implementation of Gogo::pkgpath_for_symbol was written in
a way that allowed two distinct package paths to map to the same
symbol, which could cause collisions at link- time or compile-time.
Switch to a better mangling scheme to insure that we get a unique
packagepath symbol for each package. In the new scheme instead of having
separate mangling schemes for identifiers and package paths, the
main identifier mangler ("go_encode_id") now handles mangling of
both packagepath characters and identifier characters.
The new mangling scheme is more intrusive: "foo/bar.Baz" is mangled as
"foo..z2fbar.Baz" instead of "foo_bar.Baz". To mitigate this, this
patch also adds a demangling capability so that function names
returned from runtime.CallersFrames are converted back to their
original unmangled form.
Changing the pkgpath_for_symbol scheme requires updating a number of
//go:linkname directives and C "__asm__" directives to match the new
scheme, as well as updating the 'gotest' driver (which makes
assumptions about the correct mapping from pkgpath symbol to package
name).
Fixesgolang/go#27534.
Reviewed-on: https://go-review.googlesource.com/c/135455
From-SVN: r265510
PR go/87661
runtime: remove unused armArch, hwcap and hardDiv
After CL 140057 these are only written but never read in gccgo.
Reviewed-on: https://go-review.googlesource.com/c/141077
From-SVN: r265439
Introduce a new "types" command to the export data to record the
number of types and the size of their export data. It is immediately
followed by new "type" commands that can be indexed. Parse all the
exported types immediately so that we register them, but parse other
type data only as needed.
Reviewed-on: https://go-review.googlesource.com/c/143022
From-SVN: r265409
Previously when export data referred to a type that was not defined in
a directly imported package, we would write the package name as
additional information in the type's export data. That approach
required all type information to be read in order. This patch changes
the compiler to find all references to indirectly imported packages,
and write them out as an indirectimport line in the import data. This
will permit us to read exported type data out of order.
The type traversal used to find indirect imports is a little more
complicated than necessary in preparation for later patches in this
series.
Reviewed-on: https://go-review.googlesource.com/c/143020
From-SVN: r265296
