Elmo HARSFEN0602 Alphabetic reference, Bitwise and Operator, Purpose, Algorithm, Attributes

HARSFEN0602ElmoHARmonicaSoftwareManual		PRELIMINARYDRAFT
	function table is given as an argument
GET_COMM	Call to function service of a ‘get’ command whose index in the
	function table is given as an argument
SYSSUBJ	Call to system function whose index in function table is		given as
	an argument
USRSUBJ	Call to user subroutine whose index in the symbol function table is
	given as	argument (push relevant function data to stack)
USRSUBRT	Return from user subroutine – restore stack to its state before function
	call, save output arguments in stack and jump to return address
FORITR	Handle FOR loop – check condition, if true iterate and execute loop
	body. Otherwise, break loop and continue program
EOL	Indicate this is end of line
FREEVAC	Stop program execution
LINK	Increase stack pointer with the value given as an argument and zeroes
	the new entries to stack
JMP_LABEL	Unconditional jump to the label (entry point)

Table 7-1 – Harmonica op codes

7.7Alphabetic reference

This section details the Harmonica virtual assembly commands.

7.7.1ADD - ADDITION

Purpose:

Addition of two numbers (top two entries at the stack) .

	Algorithm:
	(SP-1) + (SP) (SP-1)
	SP	SP-1
	Attributes
	Attribute			Value		Comment
	Op code					May change in future
						versions
	Number of arguments			None
	Argument types			N.A.		Both arguments types are set
			→			according to stack members
						flags
	Addressing modes			Absent
		→
	Promotion			Int + Float
				Executes as
				(float) Int + Float
	Output type			Int + int int
				Int + Float	Float
				Float + Float	Float
	Imposes end of line			No
7.7.2		AND – Bitwise AND Operator

Purpose:

Bitwise AND operator – top two entries at the stack.
Algorithm:		→	→
(SP-1) & (SP)	(SP-1)
SP →SP - 1	→		→

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