---
title: asc_ldca
description: "| 产品 | 是否支持 |"
url: https://www.hiascend.com/document/detail/zh/canncommercial/latest/API/ascendcopapi/atlasascendc_api_07_10557.html
sourcePath: /source/zh/canncommercial/900/API/ascendcopapi/atlasascendc_api_07_10557.html
indexId: 374a6fe4efb9a60e17dd38136e9202c1de892116788611873c2c5e47b85aab2e77
---
# asc_ldca

#### 产品支持情况

| 产品 | 是否支持 |
| --- | --- |
| Atlas 350 加速卡 | √ |
| Atlas A3 训练系列产品 / Atlas A3 推理系列产品 | x |
| Atlas A2 训练系列产品 / Atlas A2 推理系列产品 | x |
| Atlas 200I/500 A2 推理产品 | x |
| Atlas 推理系列产品 AI Core | x |
| Atlas 推理系列产品 Vector Core | x |
| Atlas 训练系列产品 | x |


#### 功能说明

首先从Data Cache加载缓存数据，若未命中，则尝试从L2 Cache加载。L2 Cache与Global Memory之间的数据一致性由硬件保证。如果Data Cache和L2 Cache中均未找到所需数据，则从Global Memory中读取数据，然后将其缓存到L2 Cache和Data Cache中。


#### 函数原型

```
inline long int asc_ldca(long int* address)
```


```
inline unsigned long int asc_ldca(unsigned long int* address)
```


```
inline long long int asc_ldca(long long int* address)
```


```
inline unsigned long long int asc_ldca(unsigned long long int* address)
```


```
inline long2 asc_ldca(long2* address)
```


```
inline ulong2 asc_ldca(ulong2* address)
```


```
inline long4 asc_ldca(long4* address)
```


```
inline ulong4 asc_ldca(ulong4* address)
```


```
inline longlong2 asc_ldca(longlong2* address)
```


```
inline ulonglong2 asc_ldca(ulonglong2* address)
```


```
inline longlong4 asc_ldca(longlong4* address)
```


```
inline ulonglong4 asc_ldca(ulonglong4* address)
```


```
inline signed char asc_ldca(signed char* address)
```


```
inline unsigned char asc_ldca(unsigned char* address)
```


```
inline char2 asc_ldca(char2* address)
```


```
inline uchar2 asc_ldca(uchar2* address)
```


```
inline char4 asc_ldca(char4* address)
```


```
inline uchar4 asc_ldca(uchar4* address)
```


```
inline short asc_ldca(short* address)
```


```
inline unsigned short asc_ldca(unsigned short* address)
```


```
inline short2 asc_ldca(short2* address)
```


```
inline ushort2 asc_ldca(ushort2* address)
```


```
inline short4 asc_ldca(short4* address)
```


```
inline ushort4 asc_ldca(ushort4* address)
```


```
inline int asc_ldca(int* address)
```


```
inline unsigned int asc_ldca(unsigned int* address)
```


```
inline int2 asc_ldca(int2* address)
```


```
inline uint2 asc_ldca(uint2* address)
```


```
inline int4 asc_ldca(int4* address)
```


```
inline uint4 asc_ldca(uint4* address)
```


```
inline float asc_ldca(float* address)
```


```
inline float2 asc_ldca(float2* address)
```


```
inline float4 asc_ldca(float4* address)
```


```
inline bfloat16_t asc_ldca(bfloat16_t* address)
```


```
inline bfloat16x2_t asc_ldca(bfloat16x2_t* address)
```


```
inline half asc_ldca(half* address)
```


```
inline half2 asc_ldca(half2* address)
```


#### 参数说明


**表1 参数说明**

| 参数名 | 输入/输出 | 描述 |
| --- | --- | --- |
| address | 输入 | Global Memory的地址。 |


#### 返回值说明

Data Cache或L2 Cache中的缓存数据，或输入的Global Memory地址上的数据。


#### 约束说明

SIMT编程场景当前不支持使用该接口。


#### 需要包含的头文件

使用除half、half2、bfloat16_t、bfloat16x2_t类型之外的接口需要包含"simt_api/device_functions.h"头文件，使用half和half2类型接口需要包含"simt_api/asc_fp16.h"头文件，使用bfloat16_t和bfloat16x2_t类型接口需要包含"simt_api/asc_bf16.h"头文件。

```
#include "simt_api/device_functions.h"
```

```
#include "simt_api/asc_fp16.h"
```

```
#include "simt_api/asc_bf16.h"
```


#### 调用示例

SIMD与SIMT混合编程场景：```
//混合编程场景，使用地址空间限定符__gm__表示Global Memory内存空间。
__simt_vf__ __launch_bounds__(1024) inline void kernel_asc_ldca(__gm__ float* dst, __gm__ float* src)
{
    int idx = threadIdx.x + blockIdx.x * blockDim.x;
    dst[idx] = asc_ldca(src + idx);
}
```