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// This function is used to check for the CPU's support for the sdiv
// instruction at runtime. It will either return the value 1 or
// will cause an invalid instruction trap (SIGILL signal). The
// caller must arrange for the signal handler to set the r0
// register to 0 and move the pc forward by 4 bytes (to skip
// the invalid instruction).
#include "asm_support_arm.S"
.section .text
ENTRY CheckForARMSDIVInstruction
mov r1,#1
// depending on the architecture, the assembler will not allow an
// sdiv instruction, so we will have to output the bytes directly.
// sdiv r0,r1,r1 is two words: 0xfb91 0xf1f0. We need little endian.
.byte 0x91,0xfb,0xf1,0xf0
// if the divide worked, r0 will have the value #1 (result of sdiv).
// It will have 0 otherwise (set by the signal handler)
// the value is just returned from this function.
bx lr
END CheckForARMSDIVInstruction