/*===-- divsi3.S - 32-bit signed integer divide ---------------------------===// * * The LLVM Compiler Infrastructure * * This file is dual licensed under the MIT and the University of Illinois Open * Source Licenses. See LICENSE.TXT for details. * *===----------------------------------------------------------------------===// * * This file implements the __divsi3 (32-bit signed integer divide) function * for the ARM architecture as a wrapper around the unsigned routine. * *===----------------------------------------------------------------------===*/ #include "../assembly.h" #define ESTABLISH_FRAME \ push {r4, r7, lr} ;\ add r7, sp, #4 #define CLEAR_FRAME_AND_RETURN \ pop {r4, r7, pc} .syntax unified .text #if __ARM_ARCH_ISA_THUMB == 2 .thumb #endif .p2align 3 // Ok, APCS and AAPCS agree on 32 bit args, so it's safe to use the same routine. DEFINE_AEABI_FUNCTION_ALIAS(__aeabi_idiv, __divsi3) DEFINE_COMPILERRT_FUNCTION(__divsi3) #if __ARM_ARCH_EXT_IDIV__ tst r1,r1 beq LOCAL_LABEL(divzero) sdiv r0, r0, r1 bx lr LOCAL_LABEL(divzero): mov r0,#0 bx lr #else ESTABLISH_FRAME // Set aside the sign of the quotient. eor r4, r0, r1 // Take absolute value of a and b via abs(x) = (x^(x >> 31)) - (x >> 31). eor r2, r0, r0, asr #31 eor r3, r1, r1, asr #31 sub r0, r2, r0, asr #31 sub r1, r3, r1, asr #31 // abs(a) / abs(b) bl SYMBOL_NAME(__udivsi3) // Apply sign of quotient to result and return. eor r0, r0, r4, asr #31 sub r0, r0, r4, asr #31 CLEAR_FRAME_AND_RETURN #endif END_COMPILERRT_FUNCTION(__divsi3)