Delete old versions of GCC.

Change-Id: I710f125d905290e1024cbd67f48299861790c66c

1 files changed, 0 insertions, 181 deletions

diff --git a/gcc-4.7/libgo/runtime/sema.goc b/gcc-4.7/libgo/runtime/sema.goc
deleted file mode 100644
index ff9c4f2e1..000000000
--- a/gcc-4.7/libgo/runtime/sema.goc
+++ /dev/null
@@ -1,181 +0,0 @@
-// 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.
-
-// Semaphore implementation exposed to Go.
-// Intended use is provide a sleep and wakeup
-// primitive that can be used in the contended case
-// of other synchronization primitives.
-// Thus it targets the same goal as Linux's futex,
-// but it has much simpler semantics.
-//
-// That is, don't think of these as semaphores.
-// Think of them as a way to implement sleep and wakeup
-// such that every sleep is paired with a single wakeup,
-// even if, due to races, the wakeup happens before the sleep.
-//
-// See Mullender and Cox, ``Semaphores in Plan 9,''
-// http://swtch.com/semaphore.pdf
-
-package sync
-#include "runtime.h"
-#include "arch.h"
-
-typedef struct Sema Sema;
-struct Sema
-{
-	uint32 volatile *addr;
-	G *g;
-	Sema *prev;
-	Sema *next;
-};
-
-typedef struct SemaRoot SemaRoot;
-struct SemaRoot
-{
-        Lock;
-	Sema *head;
-	Sema *tail;
-	// Number of waiters. Read w/o the lock.
-	uint32 volatile nwait;
-};
-
-// Prime to not correlate with any user patterns.
-#define SEMTABLESZ 251
-
-static union
-{
-	SemaRoot;
-	uint8 pad[CacheLineSize];
-} semtable[SEMTABLESZ];
-
-static SemaRoot*
-semroot(uint32 volatile *addr)
-{
-	return &semtable[((uintptr)addr >> 3) % SEMTABLESZ];
-}
-
-static void
-semqueue(SemaRoot *root, uint32 volatile *addr, Sema *s)
-{
-	s->g = runtime_g();
-	s->addr = addr;
-	s->next = nil;
-	s->prev = root->tail;
-	if(root->tail)
-		root->tail->next = s;
-	else
-		root->head = s;
-	root->tail = s;
-}
-
-static void
-semdequeue(SemaRoot *root, Sema *s)
-{
-	if(s->next)
-		s->next->prev = s->prev;
-	else
-		root->tail = s->prev;
-	if(s->prev)
-		s->prev->next = s->next;
-	else
-		root->head = s->next;
-	s->prev = nil;
-	s->next = nil;
-}
-
-static int32
-cansemacquire(uint32 volatile *addr)
-{
-	uint32 v;
-
-	while((v = runtime_atomicload(addr)) > 0)
-		if(runtime_cas(addr, v, v-1))
-			return 1;
-	return 0;
-}
-
-void
-runtime_semacquire(uint32 volatile *addr)
-{
-	G *g;
-	Sema s;
-	SemaRoot *root;
-
-	// Easy case.
-	if(cansemacquire(addr))
-		return;
-
-	// Harder case:
-	//	increment waiter count
-	//	try cansemacquire one more time, return if succeeded
-	//	enqueue itself as a waiter
-	//	sleep
-	//	(waiter descriptor is dequeued by signaler)
-	g = runtime_g();
-	root = semroot(addr);
-	for(;;) {
-
-		runtime_lock(root);
-		// Add ourselves to nwait to disable "easy case" in semrelease.
-		runtime_xadd(&root->nwait, 1);
-		// Check cansemacquire to avoid missed wakeup.
-		if(cansemacquire(addr)) {
-			runtime_xadd(&root->nwait, -1);
-			runtime_unlock(root);
-			return;
-		}
-		// Any semrelease after the cansemacquire knows we're waiting
-		// (we set nwait above), so go to sleep.
-		semqueue(root, addr, &s);
-		g->status = Gwaiting;
-		g->waitreason = "semacquire";
-		runtime_unlock(root);
-		runtime_gosched();
-		if(cansemacquire(addr))
-			return;
-	}
-}
-
-void
-runtime_semrelease(uint32 volatile *addr)
-{
-	Sema *s;
-	SemaRoot *root;
-
-	root = semroot(addr);
-	runtime_xadd(addr, 1);
-
-	// Easy case: no waiters?
-	// This check must happen after the xadd, to avoid a missed wakeup
-	// (see loop in semacquire).
-	if(runtime_atomicload(&root->nwait) == 0)
-		return;
-
-	// Harder case: search for a waiter and wake it.
-	runtime_lock(root);
-	if(runtime_atomicload(&root->nwait) == 0) {
-		// The count is already consumed by another goroutine,
-		// so no need to wake up another goroutine.
-		runtime_unlock(root);
-		return;
-	}
-	for(s = root->head; s; s = s->next) {
-		if(s->addr == addr) {
-			runtime_xadd(&root->nwait, -1);
-			semdequeue(root, s);
-			break;
-		}
-	}
-	runtime_unlock(root);
-	if(s)
-		runtime_ready(s->g);
-}
-
-func runtime_Semacquire(addr *uint32) {
-	runtime_semacquire(addr);
-}
-
-func runtime_Semrelease(addr *uint32) {
-	runtime_semrelease(addr);
-}