C inline assembly

Compilation can make the program more efficient, but it should be used only when there is interaction with the hardware, so you know the basic syntax.

_ ASM _ volatile __(

"Movl % 1, % eax" // There is no \ n \ t direct semicolon in the book, and there has been an error in compilation,
"Movl % 2, % EBX"
"Movl % eax, % 0"
: "= R" (REG)

: "R" (CE), "R" (EE ))

The following code is from the Linux kernel programming, But I directly compiled an error in the book,

# Include <stdio. h>
# Include <string. h>
# Include <stdlib. h>
 
Int fun ()
{
Int EE = 0X4000, Ce = 0 x8000, reg;
 
_ ASM _ volatile __(
"Movl % 1, % eax \ n \ t"
"Movl % 2, % EBX \ n \ t"
"Movl % eax, % 0 \ n \ t"
: "= R" (REG)
: "R" (CE), "R" (EE)
: "% Eax", "% EBX ");
 
Printf ("Reg = % x", Reg );
Return 0;
}
 

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