Texas Instruments TMS34010 User Manual

TMS34010 C Run-Time Environment
5.5.5 Restoration of the Caller's Environment
It is the responsibility of the called function to restore the environment of the
caller before returning. In general, this involves restoration of the caller's reg-
isters and
deletion of the local frame (including arguments).
The first task
is to restore the caller's registers. This can be done with an
MMFM instruction, corresponding to the MMTM given at function entry.
Note
that the status register need not be saved or restored. If local variables
were allocated, the frame pointer must also be restored and shouid be included
in the register list for the register save instructions.
There
are two methods for deletion of local variables and arguments:
• Function returns value on stack, or has arguments. In the latter the old
program stack pointer is pushed on the stack (below the old value). To
restore the
caller's stack, copy this value from the system stack (SP) to
the program stack pointer, A14 (STK).
• No arguments, no return value on stack. If a local frame was allocated,
decrement A14 by the size of the local frame and return. If no frame was
allocated, just return.
Note
that the old program stack pointer is not saved for either (1 ) the case of
values returned on the stack or (2) the case of no arguments.
5.5.6 Return from Function
The last instruction executed by the function is a RETS. Normally, the' in-
struction has an argument of zero, but if the function had arguments or re-
turned a
value on the stack, the instruction RETS 2 must be executed to pop
the caller's old program stack pointer off the stack,
5.6 Interrupt Handling
Interrupts can be handled directly with C functions through the use of re-
served function names. These names
are of the form: .
c- int##
where two pound signs (##) indicate a two-digit interrupt number. For ex-
ample:
c-intOO (system reset interrupt)
c-intOl .,. c-int99
By naming a function in this way, the user specifies that the function is to be
used
to handle an interrupt, and the codegen generates special code for an
interrupt routine.
Any register used (with the exception of SP and STK) is saved by the interrupt
handler, including AB. In a normal function, A8 need not be saved; however,
in the case of an interrupt, A8 must be saved.
To return from the interrupt, use the RETI instruction. This restores the status
of the interrupted function, .
5-11

Texas Instruments TMS34010 Specifications

General

Manufacturer	Texas Instruments
Model	TMS34010
Data Bus Width	32-bit
Operating Voltage	5 V
Year Introduced	1986
Category	Graphics Processor Unit (GPU)
Clock Speed	40 MHz (Maximum)
Instruction Set	Custom
Graphics Capabilities	2D graphics
Package	PGA
Resolution Support	up to 1024x768
Architecture	32-bit RISC

Summary

TMS34010 C Compiler Package Product Overview

Applicable Documents

Lists related Texas Instruments and C programming publications.

Documentation Conventions

Explains symbols and formatting used in the guide.

TMS34010 C Compiler Package Installation

Installation for Texas Instruments and IBM PC Systems

Details installation steps for PC systems, including hardware requirements and diskette usage.

VAX/VMS Systems Installation

Covers tape mounting, VMS commands, and setup for VAX/VMS.

VAX/ULTRIX and VAX/UNIX System V Installation

Outlines tape installation and tool verification for ULTRIX and UNIX systems.

Invocation and Operation of the TMS34010 C Compiler

The TMS34010 C Preprocessor (GSPCPP)

Describes GSPCPP's role in macro processing, include files, and conditional compilation.

The TMS34010 Parser (GSPCC)

Explains GSPCC's function in syntax checking and generating intermediate files.

The Code Generator (GSPCG)

Details GSPCG's process of converting intermediate code to assembly source.

Batch Execution of the C Compiler

Explains how to use GSPC.BAT for compiling and assembling C programs.

Linking a C Program

Covers modular code linking, object libraries, and the role of the linker.

The TMS34010 C Language

Identifiers and Keywords

Discusses identifier significance, case sensitivity, and new keywords.

TMS34010 C Data Types

Details basic and derived data types, including enum and void.

Structure and Union Declarations

Explains alignment, bit fields, and member name rules for structures and unions.

Enumeration Declarations

Describes the syntax and usage of named integer constants (enumerations).

TMS34010 C Run-Time Environment

Memory Model

Describes memory organization, including code and data placement.

Register Conventions

Outlines register usage for stack management, function calls, and general operations.

Function Call Conventions

Details how functions pass arguments, handle return values, and manage the stack.

System Initialization

Explains the creation and initialization of the C run-time environment, including stacks.

TMS34010 Run-Time Support

Memory Management

Describes C dynamic memory management routines like malloc, calloc, and free.

String Functions

Lists and describes functions for string manipulation, search, and comparison.

Character Typing and Conversion Macros

Explains macros for identifying character types and converting between cases.

Fatal Errors

Compiler Error Messages

Describes the format and common fatal error messages from the compiler.

Floating Point Facility

Single-Precision Floating-Point Format

Details the 32-bit format for single-precision floating-point numbers.

Double-Precision Floating-Point Format

Details the 64-bit format for double-precision floating-point numbers.

Floating Point Conversions

Explains conversions between integer, float, and double types.

Floating-Point Error Exception Handling

Describes how to trap and handle floating-point errors using fp-error.