4.8 Declarations

Specify the number of bytes per word (N) on the machine that generated the Tcode module including this instruction. If a BPW instruction is present, the module containg BPW may only be processed by backends (such as native code generators or virtual Tcode machines) that use the same machine word size. Modules not containing any BPW instructions may be processed by any backend. If multiple BPW records are present in one module, they must all declare the same value.

Define a label identified by the value L which tags a subsequent procedure.

Define a word-size storage location holding the address of the procedure tagged by the label L.

Define a word-size storage location containing the value N.

Define a vector with a length of N machine words and undefined content.

Define a label identified by the value L which tags a subsequent data object.

Define a word-size storage location holding the address of the data object tagged by the label L.

Originally used to initialize the Tcode environment - hence its name. Each program must begin with this instruction. The argument N specifies the Tcode version the program complies to. This document describes version 8 of the Tcode language. L is a code label tagging the initial entry point of the Tcode module containing the instruction. This label may be evaluated by a Tcode linker. This is not a jump instruction.

Define a vector with a length of

(N+BPW) / BPW

machine words containing the characters C1 through CN. Each character is stored in a separate byte. All trailing bytes of the vector are filled with zeroes so that a properly terminated string is created.