ARM Compiler toolchain Using the Linker - ARM Information Center

8.35 Expression evaluation in scatter files
Using scatter files
The linker can carry out simple expression evaluation with a restricted set of operators, The
operators are +, -, *, /, AND, OR, and parentheses. The implementation of OR and AND follows C
operator precedence rules.
8.35.1 Example of using expression evaluation
8.35.2 See also
Use the directives:
#define BASE_ADDRESS 0x8000
#define ALIAS_NUMBER 0x2
#define ALIAS_SIZE 0x400
#define AN_ADDRESS (BASE_ADDRESS+(ALIAS_NUMBER*ALIAS_SIZE))
The scatter file might contain:
LOAD_FLASH AN_ADDRESS ; start address
After preprocessing, this evaluates to:
LOAD_FLASH ( 0x8000 + ( 0x2 * 0x400 )) ; start address
After evaluation, the linker parses the scatter file to produce the load region:
LOAD_FLASH 0x8800 ; start address
Concepts
• Using preprocessing commands in a scatter file on page 8-57
• Using expression evaluation in a scatter file to avoid padding on page 8-59.
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