Add qemu 2.4.0

[kvmfornfv.git] / qemu / roms / u-boot / arch / arm / lib / _modsi3.S

diff --git a/qemu/roms/u-boot/arch/arm/lib/_modsi3.S b/qemu/roms/u-boot/arch/arm/lib/_modsi3.S
new file mode 100644 (file)
index 0000000..3d31a55
--- /dev/null
+++ b/qemu/roms/u-boot/arch/arm/lib/_modsi3.S
@@ -0,0 +1,98 @@
+.macro ARM_MOD_BODY dividend, divisor, order, spare
+
+#if __LINUX_ARM_ARCH__ >= 5
+
+       clz     \order, \divisor
+       clz     \spare, \dividend
+       sub     \order, \order, \spare
+       mov     \divisor, \divisor, lsl \order
+
+#else
+
+       mov     \order, #0
+
+       @ Unless the divisor is very big, shift it up in multiples of
+       @ four bits, since this is the amount of unwinding in the main
+       @ division loop.  Continue shifting until the divisor is
+       @ larger than the dividend.
+1:     cmp     \divisor, #0x10000000
+       cmplo   \divisor, \dividend
+       movlo   \divisor, \divisor, lsl #4
+       addlo   \order, \order, #4
+       blo     1b
+
+       @ For very big divisors, we must shift it a bit at a time, or
+       @ we will be in danger of overflowing.
+1:     cmp     \divisor, #0x80000000
+       cmplo   \divisor, \dividend
+       movlo   \divisor, \divisor, lsl #1
+       addlo   \order, \order, #1
+       blo     1b
+
+#endif
+
+       @ Perform all needed substractions to keep only the reminder.
+       @ Do comparisons in batch of 4 first.
+       subs    \order, \order, #3              @ yes, 3 is intended here
+       blt     2f
+
+1:     cmp     \dividend, \divisor
+       subhs   \dividend, \dividend, \divisor
+       cmp     \dividend, \divisor,  lsr #1
+       subhs   \dividend, \dividend, \divisor, lsr #1
+       cmp     \dividend, \divisor,  lsr #2
+       subhs   \dividend, \dividend, \divisor, lsr #2
+       cmp     \dividend, \divisor,  lsr #3
+       subhs   \dividend, \dividend, \divisor, lsr #3
+       cmp     \dividend, #1
+       mov     \divisor, \divisor, lsr #4
+       subges  \order, \order, #4
+       bge     1b
+
+       tst     \order, #3
+       teqne   \dividend, #0
+       beq     5f
+
+       @ Either 1, 2 or 3 comparison/substractions are left.
+2:     cmn     \order, #2
+       blt     4f
+       beq     3f
+       cmp     \dividend, \divisor
+       subhs   \dividend, \dividend, \divisor
+       mov     \divisor,  \divisor,  lsr #1
+3:     cmp     \dividend, \divisor
+       subhs   \dividend, \dividend, \divisor
+       mov     \divisor,  \divisor,  lsr #1
+4:     cmp     \dividend, \divisor
+       subhs   \dividend, \dividend, \divisor
+5:
+.endm
+
+       .align  5
+.globl __modsi3
+__modsi3:
+       cmp     r1, #0
+       beq     Ldiv0
+       rsbmi   r1, r1, #0                      @ loops below use unsigned.
+       movs    ip, r0                          @ preserve sign of dividend
+       rsbmi   r0, r0, #0                      @ if negative make positive
+       subs    r2, r1, #1                      @ compare divisor with 1
+       cmpne   r0, r1                          @ compare dividend with divisor
+       moveq   r0, #0
+       tsthi   r1, r2                          @ see if divisor is power of 2
+       andeq   r0, r0, r2
+       bls     10f
+
+       ARM_MOD_BODY r0, r1, r2, r3
+
+10:    cmp     ip, #0
+       rsbmi   r0, r0, #0
+       mov     pc, lr
+
+
+Ldiv0:
+
+       str     lr, [sp, #-4]!
+       bl      __div0
+       mov     r0, #0                  @ About as wrong as it could be.
+       ldr     pc, [sp], #4