#include <stdio.h>
typedef signed int Int;
typedef unsigned int UInt;
__attribute__((noinline)) UInt do_udiv32 ( UInt x, UInt y )
{
UInt res;
__asm__ __volatile__(
"mov r9, %1 ; mov r10, %2 ; udiv r3,r9,r10 ; mov %0, r3"
: "=r"(res) : "r"(x), "r"(y) : "r3", "r9", "r10"
);
return res;
}
__attribute__((noinline)) Int do_sdiv32 ( Int x, Int y )
{
UInt res;
__asm__ __volatile__(
"mov r9, %1 ; mov r10, %2 ; sdiv r3,r9,r10 ; mov %0, r3"
: "=r"(res) : "r"(x), "r"(y) : "r3", "r9", "r10"
);
return res;
}
void test ( UInt x, UInt y )
{
UInt ru = do_udiv32(x,y);
Int rs = do_sdiv32(x,y);
printf( "%08x %08x -> u:%08x s:%08x\n", x, y, ru, (UInt)rs);
}
int main ( void )
{
// Check basic operation
test( 500, 50 );
test( 500, -50 );
test( -500, 50 );
test( -500, -50 );
// Check for rounding towards zero
test( 100, 7 ); // 14.285
test( -100, 7 );
test( 100, -7 );
test( -100, -7 );
// Division by zero produces zero
test( 1, 0 );
test( 0, 0 );
test( -1, 0 );
test( 0x80000000, 0 );
test( 0x7FFFFFFF, 0 );
// Test signed range ends
test( 0x80000000, -1 ); // unrepresentable as signed 32
return 0;
}