4.6.1. Generic Optimizations (frontend). Altium TriCore

The TASKING VX-toolset TriCore is a software development toolset for the TriCore family of microcontrollers. It includes a C compiler, an assembler, a linker, a debugger and a set of libraries. The toolset supports the ISO-C standard and adds extra possibilities to program the special functions of the TriCore architecture.

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Using the C Compiler

• Level 2 - Optimize more (default): Enables more optimizations to reduce the memory footprint and/or execution time. This is the default optimization level.

• Level 3 - Optimize most: This is the highest optimization level. Use this level when your program/hardware has become too slow to meet your real-time requirements.

• Custom optimization: you can enable/disable specific optimizations on the Custom optimization page.

Optimization pragmas

If you specify a certain optimization, all code in the module is subject to that optimization. Within the C source file you can overrule the C compiler options for optimizations with

#pragma optimize flag and

#pragma endoptimize

. Nesting is allowed:

#pragma optimize e /* Enable expression

... simplification */

... C source ...

...

#pragma optimize c /* Enable common expression

... elimination. Expression

... C source ... simplification still enabled */

...

#pragma endoptimize /* Disable common expression

... elimination */

#pragma endoptimize /* Disable expression

... simplification */

The compiler optimizes the code between the pragma pair as specified.

You can enable or disable the optimizations described in the following subsection. The command line option for each optimization is given in brackets.

4.6.1. Generic Optimizations (frontend)

Common subexpression elimination (CSE) (option -Oc/-OC)

The compiler detects repeated use of the same (sub-)expression. Such a "common" expression is replaced by a variable that is initialized with the value of the expression to avoid recomputation. This method is called common subexpression elimination (CSE).

Expression simplification (option -Oe/-OE)

Multiplication by 0 or 1 and additions or subtractions of 0 are removed. Such useless expressions may be introduced by macros or by the compiler itself (for example, array subscripting).

Constant propagation (option -Op/-OP)

A variable with a known value is replaced by that value.

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Key features

C compiler
C++ compiler
assembler
linker
debugger
other utilities

Frequently asked questions

The TASKING VX-toolset for TriCore is a software development toolset for the TriCore family of microcontrollers. It includes a C compiler, C++ compiler, assembler, linker, debugger and other utilities.

The TASKING VX-toolset for TriCore supports the ISO-C standard and adds extra possibilities to program the special functions of the target.

The TASKING VX-toolset for TriCore is designed to help you develop embedded applications for the TriCore architecture.

User questions

Linda N.

How can I prevent the compiler from automatically managing special function registers (SFRs)?

Use the -msfr=none compiler option to disable automatic SFR management. Alternatively, the --no-tasking-sfr option provides similar functionality.

Linda N.

How can I selectively control which SFRs the compiler manages?

Use the -msfr=list option, specifying the SFRs you want the compiler to handle. Any SFR omitted from the list will not be automatically managed.

Linda N.

What alternative methods exist for accessing SFRs without compiler-managed access?

Direct memory access using SFR addresses, inline assembly, or custom macros/functions for SFR manipulation are viable alternatives.

Linda N.

What is the syntax of the LSL?

The documentation provides structural information and elements related to LSL syntax, such as the structure of a Linker Script File, Lexical Syntax (identifiers, expressions and definitions), and LSL Definitions. For a complete understanding of the syntax, consult specific LSL documentation.

Linda N.

What are the methods to disable automatic Special Function Register (SFR) code generation?

The --no-tasking-sfr option prevents the compiler from automatically generating code that accesses Special Function Registers (SFRs). An equivalent effect can be achieved using the -msfr=none option, which instructs the compiler not to manage any SFRs automatically. Additionally, the -msfr=list option allows specifying exactly which SFRs are handled automatically, while manual access can be performed using direct memory addresses, inline assembly, or macros.