# uvm assembly lanugage reference
uvm assembly language是uvm的伪汇编语言,可以用来生成uvm字节码,较uvm字节码更可读和维护。uvm上部分编程语言是先编译生成uvm assembly然后再生成uvm字节码的
# Features
- 一条指令占一行,除非是字符串的跨行
- 字符串需要支持转义
- 除字符串里内容外,分号后当前行内容是 可选的 'L'+行号+';' + 当前行注释
- 一行指令的开头可以有若干空白,指令名和指令参数之间可以隔着若干个空白
- .local varname 声明变量名
- 声明常量语法
.begin_const
"asd"
"Hello"
" world!"
.end_const
- 声明upvalues语法
.begin_upvalue
1 0
.end_upvalue
- 声明代码段语法
.begin_code
loadk %0 const "asd" ;L12; %0表示slot 0
closure %1 subroutine_2
move %2 %1
loadk %3 const "Hello"
loadk %4 const " world!"
call %2 3 1
return %0 1
.end_code
- .upvalues 数量 声明upvalues的数量
- .func 函数名 maxstacksize params_count use_vararg 声明proto的开始,以及proto的参数输入返回值数量等
- loadk, setglobal, return, move等指令对应相应的Lua字节码指令,后面跟着对应参数
- .end_func 结束一个proto的声明
- 一个"do end"块生成唯一一条return指令
# 指令列表
MOVE Copy a value between registers
LOADK Load a constant into a register
LOADBOOL Load a boolean into a register
LOADNIL Load nil values into a range of registers
GETUPVAL Read an upvalue into a register
GETTABLE Read a table element into a register
SETUPVAL Write a register value into an upvalue
SETTABLE Write a register value into a table element
NEWTABLE Create a new table
SELF Prepare an object method for calling
ADD Addition operator
SUB Subtraction operator
MUL Multiplication operator
DIV Division operator
MOD Modulus (remainder) operator
POW Exponentiation operator
UNM Unary minus operator
NOT Logical NOT operator
LEN Length operator
CONCAT Concatenate a range of registers
JMP Unconditional jump
EQ Equality test
LT Less than test
LE Less than or equal to test
TEST Boolean test, with conditional jump
TESTSET Boolean test, with conditional jump and assignment
CALL Call a closure
TAILCALL Perform a tail call
RETURN Return from function call
FORLOOP Iterate a numeric for loop
FORPREP Initialization for a numeric for loop
TFORLOOP Iterate a generic for loop
SETLIST Set a range of array elements for a table
CLOSURE Create a closure of a function prototype
VARARG Assign vararg function arguments to registers