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T3X - A Minimum Procedural Language
Version 8.1.5, Online Edition
Copyright(C) 1996-2004
Nils M Holm
 
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4.8 Declarations

4.7 Symbols Used to Describe Tcode

Symbol Size
(bits)
Description
M N 16+ generic numeric values
.N .M 16+ unsigned numeric values
L 16+ a label tagging a data word or a procedure
E 16+ a label referencing an external procedure
I 16+ a label referencing an interface procedure
C 8 an 8-bit character
X1...XN N*size of X a vector containing N elements of the type X
memory[X] 16+ the content of the X'th machine word of the data array
memory::X 8 the content of the X'th byte of the data array
S0...SN 16+ the N+1 elements most recently pushed onto the stack

Annotations

Normally, the most significant bit of each machine word is interpreted as a sign flag (1 indicates a negative number). The leading dot notation .N indicates that the MSB of N should be treated as a part of the value and not as a sign flag.

An address is an offset into the code or data array where the base (code or data array) is implicitly determined by the associated instruction.

There is a relation between labels (L) and addresses (A). When a label Lx tags a specific instruction at the address Ay, then Lx and Ay are exchangeable. In the following sections, L will be used to denote the creation of or the reference to a label while the notation A will be used to denote a reference to an address tagged by a label.

External labels are used to create a connection between the name of an external procedure and a reference to such a procedure.

Interface labels are used to create a connection between the name of an interface procedure and a reference to such a procedure.

S0 denotes the element most recently pushed onto the stack. When popping elements from a stack holding N+1 elements, S0 will be removed first and SN will be removed last.

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4.6 Startup Conditions
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4.8 Declarations