RealView Compilation Tools Compiler Reference Guide - ARM ...

Compiler-specific Features
typedef struct res_type
{
int res_1;
int res_2;
int res_3;
int res_4;
} res_type;
__svc(42) __value_in_regs res_type terminate_3(int procnum);
// terminate_3 returns more than
// one result
Errors
When an ARM architecture variant or ARM architecture-based processor that does not
support an SVC instruction is specified on the command line using the --cpu option, the
compiler generates an error.
See also
• --cpu=name on page 2-15
• __value_in_regs on page 4-19
• SVC on page 4-130 in the Assembler Guide.
4.1.16 __svc_indirect
The __svc_indirect keyword passes an operation code to the SVC handler in r12.
__svc_indirect is a function qualifier. It affects the type of a function.
Syntax
__svc_indirect(int svc_num)
return-type function-name(int real_num[, argument-list]);
Where:
svc_num
real_num
Is the immediate value used in the SVC instruction.
It is an expression evaluating to an integer in the range:
• 0 to 2 24 –1 (a 24-bit value) in an ARM instruction
• 0-255 (an 8-bit value) in a 16-bit Thumb instruction.
Is the value passed in r12 to the handler to determine the function
to perform.
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