RealView Compilation Tools Compiler Reference Guide - ARM ...

Compiler-specific Features
Where:
val
is a compile-time constant integer whose range is:
0 ... 65535 if you are compiling source as ARM code
0 ... 255 if you are compiling source as Thumb code.
Errors
The compiler does not recognize the __breakpoint intrinsic when compiling for a target
that does not support the BKPT instruction. The compiler generates either a warning or
an error in this case.
The undefined instruction trap is taken if a BKPT instruction is executed on an
architecture that does not support it.
Example
void func(void)
{
...
__breakpoint(0xF02C);
...
}
See also
• BKPT on page 4-129 in the Assembler Guide.
4.7.2 __builtin_clz
This builtin function inserts a CLZ instruction or an equivalent code sequence into the
instruction stream generated by the compiler. It is functionally equivalent to the intrinsic
__clz, except that the return type is int instead of unsigned char.
Note
This builtin function is a GNU compiler extension that is supported by the ARM
compiler.
See also
• __clz on page 4-69
• CLZ on page 4-53 in the Assembler Guide.
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