C++学习笔记

Mon, 01 Jan 0001 00:00:00 +0000

最近开始学C++，做一下记录。

User-defined conversion function 自定义类型转换函数

Enables implicit convension or explicit conversion from a class type to another type. 给类类型提供显示或隐式转换。

隐式转换 implicit conversion operator target_type() const; 在 RIF 中的用法 operator int8_t() const { return datum.i8; }

1.可以对整型进行隐式转换，指针进行显式转换。 2.使用 explicit 和 static_cast<> 进行显式转换。

cpp reference 举的例子：

struct X{
	// implicit conversion
	operator int() const { return 7; }

	// explicit conversion
	explicit operator int*() const { return nullptr; }

	// Error: array operator not allowed in conversion-type-id
	// operator int(*)[3]() const { return nullptr; }

	using arr_t = int[3];
	operator arr_t*() const { return nullptr; } // OK if done through typedef
	// operator arr_t () const; // Error: conversion to array not allowed in any case
};

int main(){
	X x;

	int n = static_cast<int>(x); // OK: sets n to 7
	int m = x;                   // OK: sets m to 7

	int* p = static_cast<int*>(x); // OK: sets p to null
	//int* q = x;                  // Error: no implicit conversion

	int (*pa)[3] = x; // OK
}

RVFA课程学习笔记

Mon, 01 Jan 0001 00:00:00 +0000

timeline

1980: start around, RISC-V is the fifth generation of a research project.
2010: RISC-V is the result of an evolving project.
2011: The first version of the RISC-V ISA was released.

name

the number just after “RV”: XLEN: in the Unprivileged Specification document. represents the width of registers and not the width of the instructions. Not all instruction width are allowed, only multiple of 16 bits wide.
for example, the 32 of RV32I.
RV64G:
RV64IMAFDZicsr_Zifencei

Notes on xyenchi's blog

C++学习笔记

User-defined conversion function 自定义类型转换函数

RVFA课程学习笔记

timeline

name