void
runtime·makeslice(SliceType* t, int64 len, int64 cap, Slice ret)
{
ret.array = 0;
ret.len = 0;
ret.cap = 0;
FLUSH(&ret);
#line 24 "C:\Users\ADMINI~1\AppData\Local\Temp\2\makerelease686069423\go\src\pkg\runtime\slice.goc"
// NOTE: The len > MaxMem/elemsize check here is not strictly necessary,
// but it produces a 'len out of range' error instead of a 'cap out of range' error
// when someone does make([]T, bignumber). 'cap out of range' is true too,
// but since the cap is only being supplied implicitly, saying len is clearer.
// See issue 4085.
if(len < 0 || (intgo)len != len || t->elem->size > 0 && len > MaxMem / t->elem->size)
runtime·panicstring("makeslice: len out of range");
if(cap < len || (intgo)cap != cap || t->elem->size > 0 && cap > MaxMem / 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);
}
FLUSH(&ret);
}
void
runtime·makeslice(SliceType* t, int64 len, int64 cap, Slice ret)
{
#line 24 "/home/pi/go_build/hg/go/src/pkg/runtime/slice.goc"
// NOTE: The len > MaxMem/elemsize check here is not strictly necessary,
// but it produces a 'len out of range' error instead of a 'cap out of range' error
// when someone does make([]T, bignumber). 'cap out of range' is true too,
// but since the cap is only being supplied implicitly, saying len is clearer.
// See issue 4085.
if(len < 0 || (intgo)len != len || t->elem->size > 0 && len > MaxMem / t->elem->size)
runtime·panicstring("makeslice: len out of range");
if(cap < len || (intgo)cap != cap || t->elem->size > 0 && cap > MaxMem / 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);
}
FLUSH(&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 || 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
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);
}
static void
growslice1(SliceType *t, Slice x, intgo newcap, Slice *ret)
{
intgo m;
m = x.cap;
// Using newcap directly for m+m < newcap handles
// both the case where m == 0 and also the case where
// m+m/4 wraps around, in which case the loop
// below might never terminate.
if(m+m < newcap)
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);
}
// make([]T, len, cap)会调用到这个函数来。注意这里的ret是整个结构体传进来的。所以按go的函数调用协议，返回值在栈中的布局其实是一个结构体而不是结构体指针。
// see also unsafe·NewArray
// makeslice(typ *Type, len, cap int64) (ary []any);
void
runtime·makeslice(SliceType *t, int64 len, int64 cap, Slice ret)
{
// NOTE: The len > MaxMem/elemsize check here is not strictly necessary,
// but it produces a 'len out of range' error instead of a 'cap out of range' error
// when someone does make([]T, bignumber). 'cap out of range' is true too,
// but since the cap is only being supplied implicitly, saying len is clearer.
// See issue 4085.
//(intgo)len != len是将len强制转换为go的int(依赖于机器位数,32或64),这就说明make([]T, len, cap)上面支持的len其实是int类型的
//也就意味着，在32位机器上，传一个很大的数，超过32位能表示的范围是会出错的。64位机器上没什么感觉。
if(len < 0 || (intgo)len != len || t->elem->size > 0 && len > MaxMem / t->elem->size)
runtime·panicstring("makeslice: len out of range");
if(cap < len || (intgo)cap != cap || t->elem->size > 0 && cap > MaxMem / 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);
}
}
