Specifications

32 www.xilinx.com Embedded System Tools Guide (EDK 6.2i)

1-800-255-7778 UG111 (v1.4) January 30, 2004

Chapter 1: Embedded System Tools Architecture

GNU Compiler Tools

XPS calls GNU compiler tools for compiling and linking application executables for each

processor in the system.

Given a set of C source files, a Microprocessor executable is created as follows.

MicroBlaze

mb-gcc file1.c file2.c

This command compiles and links the files into an executable that can run on the

MicroBlaze processor. The output executable is in a.out. The -o flag can be used to specify

a different file name for the output file.

In order to initialize memories in the hardware bitstream with this executable, the file

name should have an elf extension.

For further information on compiler options, mb-gcc -help can be run on the command

line. See Chapter 11, “GNU Compiler Tools” for more information.

PowerPC

powerpc-eabi-gcc file1.c file2.c

This command compiles and links the files into an executable that can run on the PowerPC

processor. The output executable is in a.out. The -o flag can be used to specify a different

file name for the output file.

In order to initialize memories in the hardware bitstream with this executable, the file

name should have an elf extension.

For further information on compiler options, powerpc-eabi-gcc -help can be run on the

command line. See Chapter 11, “GNU Compiler Tools” for more information.

Compiling with Optimization

Once you are satisfied that your program is correct, recompile your program with

optimization turned on. This will reduce the size of your executable, and reduce the

number of cycles it needs to execute. This is achieved by the following:

mb-gcc -O3 file1.c file2.c

Setting the Stack Size

By default, the EDK tools build the executable with a default stack size of 0x100 (256) bytes.

The stack size can be set at compile time by using:

mb-gcc file1.c file2.c -Wl,defsym -Wl,_STACK_SIZE=0x400

This will set the stack size to 0x400 (1024) bytes.

Software Debugging

You can debug your program in software (using a simulator, available for MicroBlaze

only), or on a board which has a Xilinx FPGA loaded with your hardware bitstream. See

Chapter 13, “Xilinx Microprocessor Debugger (XMD),” for more information.