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-rw-r--r--src/pkg/runtime/slice.c330
1 files changed, 330 insertions, 0 deletions
diff --git a/src/pkg/runtime/slice.c b/src/pkg/runtime/slice.c
new file mode 100644
index 000000000..70534279b
--- /dev/null
+++ b/src/pkg/runtime/slice.c
@@ -0,0 +1,330 @@
+// 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.
+
+#include "runtime.h"
+#include "type.h"
+#include "malloc.h"
+
+static int32 debug = 0;
+
+static void makeslice1(SliceType*, int32, int32, Slice*);
+static void growslice1(SliceType*, Slice, int32, Slice *);
+static void appendslice1(SliceType*, Slice, Slice, Slice*);
+ void runtime·slicecopy(Slice to, Slice fm, uintptr width, int32 ret);
+
+// see also unsafe·NewArray
+// makeslice(typ *Type, len, cap int64) (ary []any);
+void
+runtime·makeslice(SliceType *t, int64 len, int64 cap, Slice ret)
+{
+ if(len < 0 || (int32)len != len)
+ runtime·panicstring("makeslice: len out of range");
+ if(cap < len || (int32)cap != cap || t->elem->size > 0 && cap > ((uintptr)-1) / t->elem->size)
+ runtime·panicstring("makeslice: cap out of range");
+
+ makeslice1(t, len, cap, &ret);
+
+ if(debug) {
+ runtime·printf("makeslice(%S, %D, %D); ret=",
+ *t->string, len, cap);
+ runtime·printslice(ret);
+ }
+}
+
+static void
+makeslice1(SliceType *t, int32 len, int32 cap, Slice *ret)
+{
+ uintptr size;
+
+ size = cap*t->elem->size;
+
+ ret->len = len;
+ ret->cap = cap;
+
+ if((t->elem->kind&KindNoPointers))
+ ret->array = runtime·mallocgc(size, FlagNoPointers, 1, 1);
+ else
+ ret->array = runtime·mal(size);
+}
+
+// appendslice(type *Type, x, y, []T) []T
+void
+runtime·appendslice(SliceType *t, Slice x, Slice y, Slice ret)
+{
+ appendslice1(t, x, y, &ret);
+}
+
+static void
+appendslice1(SliceType *t, Slice x, Slice y, Slice *ret)
+{
+ int32 m;
+ uintptr w;
+
+ m = x.len+y.len;
+
+ if(m < x.len)
+ runtime·throw("append: slice overflow");
+
+ if(m > x.cap)
+ growslice1(t, x, m, ret);
+ else
+ *ret = x;
+
+ w = t->elem->size;
+ runtime·memmove(ret->array + ret->len*w, y.array, y.len*w);
+ ret->len += y.len;
+}
+
+// growslice(type *Type, x, []T, n int64) []T
+void
+runtime·growslice(SliceType *t, Slice old, int64 n, Slice ret)
+{
+ int64 cap;
+
+ if(n < 1)
+ runtime·panicstring("growslice: invalid n");
+
+ cap = old.cap + n;
+
+ if((int32)cap != cap || cap > ((uintptr)-1) / t->elem->size)
+ runtime·panicstring("growslice: cap out of range");
+
+ growslice1(t, old, cap, &ret);
+
+ FLUSH(&ret);
+
+ if(debug) {
+ runtime·printf("growslice(%S,", *t->string);
+ runtime·printslice(old);
+ runtime·printf(", new cap=%D) =", cap);
+ runtime·printslice(ret);
+ }
+}
+
+static void
+growslice1(SliceType *t, Slice x, int32 newcap, Slice *ret)
+{
+ int32 m;
+
+ m = x.cap;
+ if(m == 0)
+ m = newcap;
+ else {
+ do {
+ if(x.len < 1024)
+ m += m;
+ else
+ m += m/4;
+ } while(m < newcap);
+ }
+ makeslice1(t, x.len, m, ret);
+ runtime·memmove(ret->array, x.array, ret->len * t->elem->size);
+}
+
+// sliceslice(old []any, lb uint64, hb uint64, width uint64) (ary []any);
+void
+runtime·sliceslice(Slice old, uint64 lb, uint64 hb, uint64 width, Slice ret)
+{
+ if(hb > old.cap || lb > hb) {
+ if(debug) {
+ runtime·prints("runtime.sliceslice: old=");
+ runtime·printslice(old);
+ runtime·prints("; lb=");
+ runtime·printint(lb);
+ runtime·prints("; hb=");
+ runtime·printint(hb);
+ runtime·prints("; width=");
+ runtime·printint(width);
+ runtime·prints("\n");
+
+ runtime·prints("oldarray: nel=");
+ runtime·printint(old.len);
+ runtime·prints("; cap=");
+ runtime·printint(old.cap);
+ runtime·prints("\n");
+ }
+ runtime·panicslice();
+ }
+
+ // new array is inside old array
+ ret.len = hb - lb;
+ ret.cap = old.cap - lb;
+ ret.array = old.array + lb*width;
+
+ FLUSH(&ret);
+
+ if(debug) {
+ runtime·prints("runtime.sliceslice: old=");
+ runtime·printslice(old);
+ runtime·prints("; lb=");
+ runtime·printint(lb);
+ runtime·prints("; hb=");
+ runtime·printint(hb);
+ runtime·prints("; width=");
+ runtime·printint(width);
+ runtime·prints("; ret=");
+ runtime·printslice(ret);
+ runtime·prints("\n");
+ }
+}
+
+// sliceslice1(old []any, lb uint64, width uint64) (ary []any);
+void
+runtime·sliceslice1(Slice old, uint64 lb, uint64 width, Slice ret)
+{
+ if(lb > old.len) {
+ if(debug) {
+ runtime·prints("runtime.sliceslice: old=");
+ runtime·printslice(old);
+ runtime·prints("; lb=");
+ runtime·printint(lb);
+ runtime·prints("; width=");
+ runtime·printint(width);
+ runtime·prints("\n");
+
+ runtime·prints("oldarray: nel=");
+ runtime·printint(old.len);
+ runtime·prints("; cap=");
+ runtime·printint(old.cap);
+ runtime·prints("\n");
+ }
+ runtime·panicslice();
+ }
+
+ // new array is inside old array
+ ret.len = old.len - lb;
+ ret.cap = old.cap - lb;
+ ret.array = old.array + lb*width;
+
+ FLUSH(&ret);
+
+ if(debug) {
+ runtime·prints("runtime.sliceslice: old=");
+ runtime·printslice(old);
+ runtime·prints("; lb=");
+ runtime·printint(lb);
+ runtime·prints("; width=");
+ runtime·printint(width);
+ runtime·prints("; ret=");
+ runtime·printslice(ret);
+ runtime·prints("\n");
+ }
+}
+
+// slicearray(old *any, nel uint64, lb uint64, hb uint64, width uint64) (ary []any);
+void
+runtime·slicearray(byte* old, uint64 nel, uint64 lb, uint64 hb, uint64 width, Slice ret)
+{
+ if(nel > 0 && old == nil) {
+ // crash if old == nil.
+ // could give a better message
+ // but this is consistent with all the in-line checks
+ // that the compiler inserts for other uses.
+ *old = 0;
+ }
+
+ if(hb > nel || lb > hb) {
+ if(debug) {
+ runtime·prints("runtime.slicearray: old=");
+ runtime·printpointer(old);
+ runtime·prints("; nel=");
+ runtime·printint(nel);
+ runtime·prints("; lb=");
+ runtime·printint(lb);
+ runtime·prints("; hb=");
+ runtime·printint(hb);
+ runtime·prints("; width=");
+ runtime·printint(width);
+ runtime·prints("\n");
+ }
+ runtime·panicslice();
+ }
+
+ // new array is inside old array
+ ret.len = hb-lb;
+ ret.cap = nel-lb;
+ ret.array = old + lb*width;
+
+ FLUSH(&ret);
+
+ if(debug) {
+ runtime·prints("runtime.slicearray: old=");
+ runtime·printpointer(old);
+ runtime·prints("; nel=");
+ runtime·printint(nel);
+ runtime·prints("; lb=");
+ runtime·printint(lb);
+ runtime·prints("; hb=");
+ runtime·printint(hb);
+ runtime·prints("; width=");
+ runtime·printint(width);
+ runtime·prints("; ret=");
+ runtime·printslice(ret);
+ runtime·prints("\n");
+ }
+}
+
+// slicecopy(to any, fr any, wid uint32) int
+void
+runtime·slicecopy(Slice to, Slice fm, uintptr width, int32 ret)
+{
+ if(fm.len == 0 || to.len == 0 || width == 0) {
+ ret = 0;
+ goto out;
+ }
+
+ ret = fm.len;
+ if(to.len < ret)
+ ret = to.len;
+
+ if(ret == 1 && width == 1) { // common case worth about 2x to do here
+ *to.array = *fm.array; // known to be a byte pointer
+ } else {
+ runtime·memmove(to.array, fm.array, ret*width);
+ }
+
+out:
+ FLUSH(&ret);
+
+ if(debug) {
+ runtime·prints("main·copy: to=");
+ runtime·printslice(to);
+ runtime·prints("; fm=");
+ runtime·printslice(fm);
+ runtime·prints("; width=");
+ runtime·printint(width);
+ runtime·prints("; ret=");
+ runtime·printint(ret);
+ runtime·prints("\n");
+ }
+}
+
+void
+runtime·slicestringcopy(Slice to, String fm, int32 ret)
+{
+ if(fm.len == 0 || to.len == 0) {
+ ret = 0;
+ goto out;
+ }
+
+ ret = fm.len;
+ if(to.len < ret)
+ ret = to.len;
+
+ runtime·memmove(to.array, fm.str, ret);
+
+out:
+ FLUSH(&ret);
+}
+
+void
+runtime·printslice(Slice a)
+{
+ runtime·prints("[");
+ runtime·printint(a.len);
+ runtime·prints("/");
+ runtime·printint(a.cap);
+ runtime·prints("]");
+ runtime·printpointer(a.array);
+}