PR go/61877
refect: fix direct call of variadic method value

As reported in bug https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61877
gcc mainline has regressed in this.  This CL adds the tests proposed
for the main Go repository:

        https://codereview.appspot.com/151280043/
        https://codereview.appspot.com/152060043/

restores the code from the amd64/386 path that makes this work and
was lost when the Go 1.3 stdlib was merged and changes the FFI path
to call into the same helper code as the amd64/386 path.

I've only tested this on amd64 but I did test a version that was
patched to unconditionally take the FFI path.

From-SVN: r215859

Fixes issue 38.

From-SVN: r215832

This supports clang, which by default issues warnings about
unused command line arguments, a habit that interacts poorly
with configure scripts.

From-SVN: r215699

If the compiler inlines this function into kickoff, it may reuse
the TLS block address to load g. However, this is not necessarily
correct, as the call to g->entry in kickoff may cause the TLS
address to change. If the wrong value is loaded for g->status in
runtime_goexit, it may cause a runtime panic.

By marking the function as noinline we prevent the compiler from
reusing the TLS address.

From-SVN: r215484

From-SVN: r215423

Without this we weren't supporting the standard Cloneflags
field of SysProcAttr.

From-SVN: r214972

From-SVN: r214965

	* go-gcc.cc (Gcc_backend::implicit_variable): Remove init
	parameter.  Add is_hidden parameter.
	(Gcc_backend::implicit_variable_set_init): New method.
	(Gcc_backend::implicit_variable_reference): New method.

From-SVN: r214894

From-SVN: r214048

The Go frontend passes closures through to functions using the
functions __go_set_closure and __go_get_closure.  The
expectation is that there are no function calls between
set_closure and get_closure.  However, it turns out that there
can be function calls if some of the function arguments
require type conversion to an interface type.  Converting to
an interface type can allocate memory, and that can in turn
trigger a garbage collection, and that can in turn call pool
cleanup functions that may call __go_set_closure.  So the
called function can see the wrong closure value, which is bad.

This patch fixes the problem in two different ways.  First, we
move all type conversions in function arguments into temporary
variables so that they can not appear before the call to
__go_set_closure.  (This required shifting the flatten phase
after the simplify_thunk phase, since the latter expects to
work with unconverted argument types.)  Second, we fix the
memory allocation function to preserve the closure value
across any possible garbage collection.

A test case is the libgo database/sql check run with the
environment variable GOGC set to 1.

From-SVN: r213932

Based on patch from Rainer Orth.

From-SVN: r213599

	PR other/61895

runtime: Ignore small argv[0] file for backtrace.

Reportedly in some cases Docker starts processes with argv[0]
pointing to an empty file.  That would cause libgo to pass
that empty file to libbacktrace, which would then fail to do
any backtraces.  Everything should work fine if libbacktrace
falls back to /proc/self/exe.

This patch to libgo works around the problem by ignoring
argv[0] if it is a small file, or if stat fails.  This is not
a perfect fix but it's an unusual problem.

From-SVN: r213513

This variable is unused apparently as a result of local changes.
gccgo accepts this variable declaration, but other frontends may not.

From-SVN: r212873

This adds an import of the runtime package to fix compilation
of the TestStopCPUProfilingWithProfilerOff function.

The gccgo compiler should never have accepted this.  The patch
for the comiler is http://codereview.appspot.com/116960043 .
The test is https://codereview.appspot.com/118000043 .

From-SVN: r212870

From-SVN: r212862

Keep using the existing 386 and amd64 code on those archs,
since it is more efficient.

From-SVN: r212853

From-SVN: r212840

From-SVN: r212837

This revision renames several files in the runtime directory
from .c to .goc.

From-SVN: r212472

Rename in order to avoid confusion with the new
runtime/iface.goc file in the Go library master sources.

From-SVN: r212447

The flags were used by the reflect package in the past, but
not for a couple of years now.

From-SVN: r212446

	PR go/61620

runtime: Don't free tiny blocks in map deletion.

The memory allocator now has a special case for tiny blocks
(smaller than 16 bytes) and they can not be explicitly freed.

From-SVN: r212233

This introduces the "bench" build target, which can be used to run
all benchmarks.

It is also possible to run subsets of benchmarks with the
"package/check" build targets by setting GOBENCH to a matching regex.

From-SVN: r212212

From-SVN: r211961

	PR go/52583
runtime: Stop backtrace at a few recognized functions.

On x86_64 Solaris the makecontext function does not properly
indicate that it is at the top of the stack.  Attempting to
unwind the stack past a call to makecontext tends to crash.
This patch changes libgo to look for certain functions that
are always found at the top of the stack, and to stop
unwinding when it reaches one of those functions.  There is
never anything interesting past these functions--that is,
there is never any code written by the user.

From-SVN: r211640

	PR go/61498
runtime: Always set gcnext_sp to pointer-aligned address.

The gcnext_sp field is only used on systems that do not use
split stacks.  It marks the bottom of the stack for the
garbage collector.  This change makes sure that the stack
bottom is always aligned to a pointer value.

Previously the garbage collector would align all the addresses
that it scanned, but it now expects them to be aligned before
scanning.

From-SVN: r211639

From-SVN: r211394

The next revision, 19185, renames several runtime files, and
will be handled in a separate change.

From-SVN: r211328

This revision was committed January 7, 2014.  The next
revision deleted runtime/mfinal.c.  That will be done in a
subsequent merge.

This merge changes type descriptors to add a zero field,
pointing to a zero value for that type.  This is implemented
as a common variable.

	* go-gcc.cc (Gcc_backend::implicit_variable): Add is_common and
	alignment parameters.  Permit init parameter to be NULL.

From-SVN: r211249

Based on a patch from Peter Collingbourne.

From-SVN: r211081

This adds the --without-libatomic configure option, which is useful for building libgo
with a non-gcc compiler.

It disables libgo's dependency on libatomic. This
is useful for platforms where it is known that the libatomic runtime
functions are not required, or where the compiler automatically
provides an implementation of them.

From-SVN: r211065

LLVM's code generator does not currently support split stacks for vararg
functions, so we disable split stacks for the only function that uses this
feature under Clang. This appears to be OK as long as:
- this function only calls non-inlined, internal-linkage (hence no dynamic
  loader) functions compiled with split stacks (i.e. go_vprintf), which can
  allocate more stack space as required;
- this function itself does not occupy more than BACKOFF bytes of stack space
  (see libgcc/config/i386/morestack.S).
These conditions are currently known to be satisfied by Clang on x86-32 and
x86-64. Note that signal handlers receive slightly less stack space than they
would normally do if they happen to be called while this function is being
run. If this turns out to be a problem we could consider increasing BACKOFF.

From-SVN: r211037

This includes the use of __complex and __builtin_ functions where
unprefixed entities would suffice, and the use of a union for
bit-casting between types.

From-SVN: r211036

Result of runtime_write is ignored, causing
an unused-result result warning (error in my
case, with -Werror=unused-result).

From-SVN: r210987

From-SVN: r210192

From-SVN: r210189

The Go compiler may have different values for these than the C compiler.

From-SVN: r209967

	PR go/60931

runtime: Fix garbage collector issue with non 4kB system page size

The go garbage collector tracks memory in terms of 4kB pages.
Most of the code checks getpagesize() at runtime and does the
right thing.

On a 64kB ppc64 box I see SEGVs in long running processes
which has been diagnosed as a bug in scavengelist.
scavengelist does a madvise(MADV_DONTNEED) without rounding
the arguments to the system page size.  A strace of one of the
failures shows the problem:

madvise(0xc211030000, 4096, MADV_DONTNEED) = 0

The kernel rounds the length up to 64kB and we mark 60kB of
valid data as no longer needed.

Round start up to a system page and end down before calling
madvise.

From-SVN: r209777

A gccgo language extension allows a function to be declared multiple
times. Avoid the use of this extension by dedeplicating declarations
in mksyscall.awk.

From-SVN: r209508

The use of this syntax was eliminated upstream in Go 992248b2adc2,
but this particular use slipped through somehow.

From-SVN: r209506