all: merge dev.cc (81884b89bd88) into default

With this change, default now contains Go 1.5 work.
Any future bug fixes for Go 1.4 in the compilers or
the runtime will have to be made directly to the
release branch.

1 files changed, 606 insertions, 0 deletions

diff --git a/src/runtime/runtime2.go b/src/runtime/runtime2.go
new file mode 100644
index 000000000..7987a7373
--- /dev/null
+++ b/src/runtime/runtime2.go
@@ -0,0 +1,606 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "unsafe"
+
+/*
+ * defined constants
+ */
+const (
+	// G status
+	//
+	// If you add to this list, add to the list
+	// of "okay during garbage collection" status
+	// in mgc0.c too.
+	_Gidle            = iota // 0
+	_Grunnable               // 1 runnable and on a run queue
+	_Grunning                // 2
+	_Gsyscall                // 3
+	_Gwaiting                // 4
+	_Gmoribund_unused        // 5 currently unused, but hardcoded in gdb scripts
+	_Gdead                   // 6
+	_Genqueue                // 7 Only the Gscanenqueue is used.
+	_Gcopystack              // 8 in this state when newstack is moving the stack
+	// the following encode that the GC is scanning the stack and what to do when it is done
+	_Gscan = 0x1000 // atomicstatus&~Gscan = the non-scan state,
+	// _Gscanidle =     _Gscan + _Gidle,      // Not used. Gidle only used with newly malloced gs
+	_Gscanrunnable = _Gscan + _Grunnable //  0x1001 When scanning complets make Grunnable (it is already on run queue)
+	_Gscanrunning  = _Gscan + _Grunning  //  0x1002 Used to tell preemption newstack routine to scan preempted stack.
+	_Gscansyscall  = _Gscan + _Gsyscall  //  0x1003 When scanning completes make is Gsyscall
+	_Gscanwaiting  = _Gscan + _Gwaiting  //  0x1004 When scanning completes make it Gwaiting
+	// _Gscanmoribund_unused,               //  not possible
+	// _Gscandead,                          //  not possible
+	_Gscanenqueue = _Gscan + _Genqueue //  When scanning completes make it Grunnable and put on runqueue
+)
+
+const (
+	// P status
+	_Pidle = iota
+	_Prunning
+	_Psyscall
+	_Pgcstop
+	_Pdead
+)
+
+// The next line makes 'go generate' write the zgen_*.go files with
+// per-OS and per-arch information, including constants
+// named goos_$GOOS and goarch_$GOARCH for every
+// known GOOS and GOARCH. The constant is 1 on the
+// current system, 0 otherwise; multiplying by them is
+// useful for defining GOOS- or GOARCH-specific constants.
+//go:generate go run gengoos.go
+
+type mutex struct {
+	// Futex-based impl treats it as uint32 key,
+	// while sema-based impl as M* waitm.
+	// Used to be a union, but unions break precise GC.
+	key uintptr
+}
+
+type note struct {
+	// Futex-based impl treats it as uint32 key,
+	// while sema-based impl as M* waitm.
+	// Used to be a union, but unions break precise GC.
+	key uintptr
+}
+
+type _string struct {
+	str *byte
+	len int
+}
+
+type funcval struct {
+	fn uintptr
+	// variable-size, fn-specific data here
+}
+
+type iface struct {
+	tab  *itab
+	data unsafe.Pointer
+}
+
+type eface struct {
+	_type *_type
+	data  unsafe.Pointer
+}
+
+type slice struct {
+	array *byte // actual data
+	len   uint  // number of elements
+	cap   uint  // allocated number of elements
+}
+
+type gobuf struct {
+	// The offsets of sp, pc, and g are known to (hard-coded in) libmach.
+	sp   uintptr
+	pc   uintptr
+	g    *g
+	ctxt unsafe.Pointer // this has to be a pointer so that gc scans it
+	ret  uintreg
+	lr   uintptr
+}
+
+// Known to compiler.
+// Changes here must also be made in src/cmd/gc/select.c's selecttype.
+type sudog struct {
+	g           *g
+	selectdone  *uint32
+	next        *sudog
+	prev        *sudog
+	elem        unsafe.Pointer // data element
+	releasetime int64
+	nrelease    int32  // -1 for acquire
+	waitlink    *sudog // g.waiting list
+}
+
+type gcstats struct {
+	// the struct must consist of only uint64's,
+	// because it is casted to uint64[].
+	nhandoff    uint64
+	nhandoffcnt uint64
+	nprocyield  uint64
+	nosyield    uint64
+	nsleep      uint64
+}
+
+type libcall struct {
+	fn   uintptr
+	n    uintptr // number of parameters
+	args uintptr // parameters
+	r1   uintptr // return values
+	r2   uintptr
+	err  uintptr // error number
+}
+
+// describes how to handle callback
+type wincallbackcontext struct {
+	gobody       unsafe.Pointer // go function to call
+	argsize      uintptr        // callback arguments size (in bytes)
+	restorestack uintptr        // adjust stack on return by (in bytes) (386 only)
+	cleanstack   bool
+}
+
+// Stack describes a Go execution stack.
+// The bounds of the stack are exactly [lo, hi),
+// with no implicit data structures on either side.
+type stack struct {
+	lo uintptr
+	hi uintptr
+}
+
+type g struct {
+	// Stack parameters.
+	// stack describes the actual stack memory: [stack.lo, stack.hi).
+	// stackguard0 is the stack pointer compared in the Go stack growth prologue.
+	// It is stack.lo+StackGuard normally, but can be StackPreempt to trigger a preemption.
+	// stackguard1 is the stack pointer compared in the C stack growth prologue.
+	// It is stack.lo+StackGuard on g0 and gsignal stacks.
+	// It is ~0 on other goroutine stacks, to trigger a call to morestackc (and crash).
+	stack       stack   // offset known to runtime/cgo
+	stackguard0 uintptr // offset known to liblink
+	stackguard1 uintptr // offset known to liblink
+
+	_panic       *_panic // innermost panic - offset known to liblink
+	_defer       *_defer // innermost defer
+	sched        gobuf
+	syscallsp    uintptr        // if status==gsyscall, syscallsp = sched.sp to use during gc
+	syscallpc    uintptr        // if status==gsyscall, syscallpc = sched.pc to use during gc
+	param        unsafe.Pointer // passed parameter on wakeup
+	atomicstatus uint32
+	goid         int64
+	waitsince    int64  // approx time when the g become blocked
+	waitreason   string // if status==gwaiting
+	schedlink    *g
+	issystem     bool // do not output in stack dump, ignore in deadlock detector
+	preempt      bool // preemption signal, duplicates stackguard0 = stackpreempt
+	paniconfault bool // panic (instead of crash) on unexpected fault address
+	preemptscan  bool // preempted g does scan for gc
+	gcworkdone   bool // debug: cleared at begining of gc work phase cycle, set by gcphasework, tested at end of cycle
+	throwsplit   bool // must not split stack
+	raceignore   int8 // ignore race detection events
+	m            *m   // for debuggers, but offset not hard-coded
+	lockedm      *m
+	sig          uint32
+	writebuf     []byte
+	sigcode0     uintptr
+	sigcode1     uintptr
+	sigpc        uintptr
+	gopc         uintptr // pc of go statement that created this goroutine
+	racectx      uintptr
+	waiting      *sudog // sudog structures this g is waiting on (that have a valid elem ptr)
+	end          [0]byte
+}
+
+type mts struct {
+	tv_sec  int64
+	tv_nsec int64
+}
+
+type mscratch struct {
+	v [6]uintptr
+}
+
+type m struct {
+	g0      *g    // goroutine with scheduling stack
+	morebuf gobuf // gobuf arg to morestack
+
+	// Fields not known to debuggers.
+	procid        uint64         // for debuggers, but offset not hard-coded
+	gsignal       *g             // signal-handling g
+	tls           [4]uintptr     // thread-local storage (for x86 extern register)
+	mstartfn      unsafe.Pointer // todo go func()
+	curg          *g             // current running goroutine
+	caughtsig     *g             // goroutine running during fatal signal
+	p             *p             // attached p for executing go code (nil if not executing go code)
+	nextp         *p
+	id            int32
+	mallocing     int32
+	throwing      int32
+	gcing         int32
+	locks         int32
+	softfloat     int32
+	dying         int32
+	profilehz     int32
+	helpgc        int32
+	spinning      bool // m is out of work and is actively looking for work
+	blocked       bool // m is blocked on a note
+	fastrand      uint32
+	ncgocall      uint64 // number of cgo calls in total
+	ncgo          int32  // number of cgo calls currently in progress
+	cgomal        *cgomal
+	park          note
+	alllink       *m // on allm
+	schedlink     *m
+	machport      uint32 // return address for mach ipc (os x)
+	mcache        *mcache
+	lockedg       *g
+	createstack   [32]uintptr // stack that created this thread.
+	freglo        [16]uint32  // d[i] lsb and f[i]
+	freghi        [16]uint32  // d[i] msb and f[i+16]
+	fflag         uint32      // floating point compare flags
+	locked        uint32      // tracking for lockosthread
+	nextwaitm     *m          // next m waiting for lock
+	waitsema      uintptr     // semaphore for parking on locks
+	waitsemacount uint32
+	waitsemalock  uint32
+	gcstats       gcstats
+	needextram    bool
+	traceback     uint8
+	waitunlockf   unsafe.Pointer // todo go func(*g, unsafe.pointer) bool
+	waitlock      unsafe.Pointer
+	//#ifdef GOOS_windows
+	thread uintptr // thread handle
+	// these are here because they are too large to be on the stack
+	// of low-level NOSPLIT functions.
+	libcall   libcall
+	libcallpc uintptr // for cpu profiler
+	libcallsp uintptr
+	libcallg  *g
+	//#endif
+	//#ifdef GOOS_solaris
+	perrno *int32 // pointer to tls errno
+	// these are here because they are too large to be on the stack
+	// of low-level NOSPLIT functions.
+	//LibCall	libcall;
+	ts      mts
+	scratch mscratch
+	//#endif
+	//#ifdef GOOS_plan9
+	notesig *int8
+	errstr  *byte
+	//#endif
+	end [0]byte
+}
+
+type p struct {
+	lock mutex
+
+	id          int32
+	status      uint32 // one of pidle/prunning/...
+	link        *p
+	schedtick   uint32 // incremented on every scheduler call
+	syscalltick uint32 // incremented on every system call
+	m           *m     // back-link to associated m (nil if idle)
+	mcache      *mcache
+	deferpool   [5]*_defer // pool of available defer structs of different sizes (see panic.c)
+
+	// Cache of goroutine ids, amortizes accesses to runtime·sched.goidgen.
+	goidcache    uint64
+	goidcacheend uint64
+
+	// Queue of runnable goroutines.
+	runqhead uint32
+	runqtail uint32
+	runq     [256]*g
+
+	// Available G's (status == Gdead)
+	gfree    *g
+	gfreecnt int32
+
+	pad [64]byte
+}
+
+const (
+	// The max value of GOMAXPROCS.
+	// There are no fundamental restrictions on the value.
+	_MaxGomaxprocs = 1 << 8
+)
+
+type schedt struct {
+	lock mutex
+
+	goidgen uint64
+
+	midle        *m    // idle m's waiting for work
+	nmidle       int32 // number of idle m's waiting for work
+	nmidlelocked int32 // number of locked m's waiting for work
+	mcount       int32 // number of m's that have been created
+	maxmcount    int32 // maximum number of m's allowed (or die)
+
+	pidle      *p // idle p's
+	npidle     uint32
+	nmspinning uint32
+
+	// Global runnable queue.
+	runqhead *g
+	runqtail *g
+	runqsize int32
+
+	// Global cache of dead G's.
+	gflock mutex
+	gfree  *g
+	ngfree int32
+
+	gcwaiting  uint32 // gc is waiting to run
+	stopwait   int32
+	stopnote   note
+	sysmonwait uint32
+	sysmonnote note
+	lastpoll   uint64
+
+	profilehz int32 // cpu profiling rate
+}
+
+// The m->locked word holds two pieces of state counting active calls to LockOSThread/lockOSThread.
+// The low bit (LockExternal) is a boolean reporting whether any LockOSThread call is active.
+// External locks are not recursive; a second lock is silently ignored.
+// The upper bits of m->lockedcount record the nesting depth of calls to lockOSThread
+// (counting up by LockInternal), popped by unlockOSThread (counting down by LockInternal).
+// Internal locks can be recursive. For instance, a lock for cgo can occur while the main
+// goroutine is holding the lock during the initialization phase.
+const (
+	_LockExternal = 1
+	_LockInternal = 2
+)
+
+type sigtabtt struct {
+	flags int32
+	name  *int8
+}
+
+const (
+	_SigNotify   = 1 << 0 // let signal.Notify have signal, even if from kernel
+	_SigKill     = 1 << 1 // if signal.Notify doesn't take it, exit quietly
+	_SigThrow    = 1 << 2 // if signal.Notify doesn't take it, exit loudly
+	_SigPanic    = 1 << 3 // if the signal is from the kernel, panic
+	_SigDefault  = 1 << 4 // if the signal isn't explicitly requested, don't monitor it
+	_SigHandling = 1 << 5 // our signal handler is registered
+	_SigIgnored  = 1 << 6 // the signal was ignored before we registered for it
+	_SigGoExit   = 1 << 7 // cause all runtime procs to exit (only used on Plan 9).
+)
+
+// Layout of in-memory per-function information prepared by linker
+// See http://golang.org/s/go12symtab.
+// Keep in sync with linker and with ../../libmach/sym.c
+// and with package debug/gosym and with symtab.go in package runtime.
+type _func struct {
+	entry   uintptr // start pc
+	nameoff int32   // function name
+
+	args  int32 // in/out args size
+	frame int32 // legacy frame size; use pcsp if possible
+
+	pcsp      int32
+	pcfile    int32
+	pcln      int32
+	npcdata   int32
+	nfuncdata int32
+}
+
+// layout of Itab known to compilers
+// allocated in non-garbage-collected memory
+type itab struct {
+	inter  *interfacetype
+	_type  *_type
+	link   *itab
+	bad    int32
+	unused int32
+	fun    [0]uintptr
+}
+
+// Lock-free stack node.
+type lfnode struct {
+	next    *lfnode
+	pushcnt uintptr
+}
+
+// Parallel for descriptor.
+type parfor struct {
+	body    unsafe.Pointer // go func(*parfor, uint32), executed for each element
+	done    uint32         // number of idle threads
+	nthr    uint32         // total number of threads
+	nthrmax uint32         // maximum number of threads
+	thrseq  uint32         // thread id sequencer
+	cnt     uint32         // iteration space [0, cnt)
+	ctx     unsafe.Pointer // arbitrary user context
+	wait    bool           // if true, wait while all threads finish processing,
+	// otherwise parfor may return while other threads are still working
+	thr *parforthread // array of thread descriptors
+	pad uint32        // to align parforthread.pos for 64-bit atomic operations
+	// stats
+	nsteal     uint64
+	nstealcnt  uint64
+	nprocyield uint64
+	nosyield   uint64
+	nsleep     uint64
+}
+
+// Track memory allocated by code not written in Go during a cgo call,
+// so that the garbage collector can see them.
+type cgomal struct {
+	next  *cgomal
+	alloc unsafe.Pointer
+}
+
+// Holds variables parsed from GODEBUG env var.
+type debugvars struct {
+	allocfreetrace int32
+	efence         int32
+	gctrace        int32
+	gcdead         int32
+	scheddetail    int32
+	schedtrace     int32
+	scavenge       int32
+}
+
+// Indicates to write barrier and sychronization task to preform.
+const (
+	_GCoff     = iota // stop and start             nop
+	_GCquiesce        // stop and start             nop
+	_GCstw            // stop the ps                nop
+	_GCmark           // scan the stacks and start  no white to black
+	_GCsweep          // stop and start             nop
+)
+
+type forcegcstate struct {
+	lock mutex
+	g    *g
+	idle uint32
+}
+
+var gcphase uint32
+
+/*
+ * known to compiler
+ */
+const (
+	_Structrnd = regSize
+)
+
+var startup_random_data *byte
+var startup_random_data_len uint32
+
+var invalidptr int32
+
+const (
+	// hashinit wants this many random bytes
+	_HashRandomBytes = 32
+)
+
+/*
+ * deferred subroutine calls
+ */
+type _defer struct {
+	siz     int32
+	started bool
+	argp    uintptr // where args were copied from
+	pc      uintptr
+	fn      *funcval
+	_panic  *_panic // panic that is running defer
+	link    *_defer
+}
+
+/*
+ * panics
+ */
+type _panic struct {
+	argp      unsafe.Pointer // pointer to arguments of deferred call run during panic; cannot move - known to liblink
+	arg       interface{}    // argument to panic
+	link      *_panic        // link to earlier panic
+	recovered bool           // whether this panic is over
+	aborted   bool           // the panic was aborted
+}
+
+/*
+ * stack traces
+ */
+
+type stkframe struct {
+	fn       *_func     // function being run
+	pc       uintptr    // program counter within fn
+	continpc uintptr    // program counter where execution can continue, or 0 if not
+	lr       uintptr    // program counter at caller aka link register
+	sp       uintptr    // stack pointer at pc
+	fp       uintptr    // stack pointer at caller aka frame pointer
+	varp     uintptr    // top of local variables
+	argp     uintptr    // pointer to function arguments
+	arglen   uintptr    // number of bytes at argp
+	argmap   *bitvector // force use of this argmap
+}
+
+const (
+	_TraceRuntimeFrames = 1 << 0 // include frames for internal runtime functions.
+	_TraceTrap          = 1 << 1 // the initial PC, SP are from a trap, not a return PC from a call
+)
+
+const (
+	// The maximum number of frames we print for a traceback
+	_TracebackMaxFrames = 100
+)
+
+var (
+	emptystring string
+	allg        **g
+	allglen     uintptr
+	lastg       *g
+	allm        *m
+	allp        [_MaxGomaxprocs + 1]*p
+	gomaxprocs  int32
+	needextram  uint32
+	panicking   uint32
+	goos        *int8
+	ncpu        int32
+	iscgo       bool
+	cpuid_ecx   uint32
+	cpuid_edx   uint32
+	debug       debugvars
+	signote     note
+	forcegc     forcegcstate
+	sched       schedt
+	newprocs    int32
+)
+
+/*
+ * mutual exclusion locks.  in the uncontended case,
+ * as fast as spin locks (just a few user-level instructions),
+ * but on the contention path they sleep in the kernel.
+ * a zeroed Mutex is unlocked (no need to initialize each lock).
+ */
+
+/*
+ * sleep and wakeup on one-time events.
+ * before any calls to notesleep or notewakeup,
+ * must call noteclear to initialize the Note.
+ * then, exactly one thread can call notesleep
+ * and exactly one thread can call notewakeup (once).
+ * once notewakeup has been called, the notesleep
+ * will return.  future notesleep will return immediately.
+ * subsequent noteclear must be called only after
+ * previous notesleep has returned, e.g. it's disallowed
+ * to call noteclear straight after notewakeup.
+ *
+ * notetsleep is like notesleep but wakes up after
+ * a given number of nanoseconds even if the event
+ * has not yet happened.  if a goroutine uses notetsleep to
+ * wake up early, it must wait to call noteclear until it
+ * can be sure that no other goroutine is calling
+ * notewakeup.
+ *
+ * notesleep/notetsleep are generally called on g0,
+ * notetsleepg is similar to notetsleep but is called on user g.
+ */
+// bool	runtime·notetsleep(Note*, int64);  // false - timeout
+// bool	runtime·notetsleepg(Note*, int64);  // false - timeout
+
+/*
+ * Lock-free stack.
+ * Initialize uint64 head to 0, compare with 0 to test for emptiness.
+ * The stack does not keep pointers to nodes,
+ * so they can be garbage collected if there are no other pointers to nodes.
+ */
+
+/*
+ * Parallel for over [0, n).
+ * body() is executed for each iteration.
+ * nthr - total number of worker threads.
+ * ctx - arbitrary user context.
+ * if wait=true, threads return from parfor() when all work is done;
+ * otherwise, threads can return while other threads are still finishing processing.
+ */
+
+// for mmap, we only pass the lower 32 bits of file offset to the
+// assembly routine; the higher bits (if required), should be provided
+// by the assembly routine as 0.