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//===----------------------Hexagon builtin routine ------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
.macro FUNCTION_BEGIN name
.text
.p2align 5
.globl \name
.type \name, @function
\name:
.endm
.macro FUNCTION_END name
.size \name, . - \name
.endm
FUNCTION_BEGIN __hexagon_divdi3
{
p2 = tstbit(r1,#31)
p3 = tstbit(r3,#31)
}
{
r1:0 = abs(r1:0)
r3:2 = abs(r3:2)
}
{
r6 = cl0(r1:0) // count leading 0's of dividend (numerator)
r7 = cl0(r3:2) // count leading 0's of divisor (denominator)
r5:4 = r3:2 // divisor moved into working registers
r3:2 = r1:0 // dividend is the initial remainder, r3:2 contains remainder
}
{
p3 = xor(p2,p3)
r10 = sub(r7,r6) // left shift count for bit & divisor
r1:0 = #0 // initialize quotient to 0
r15:14 = #1 // initialize bit to 1
}
{
r11 = add(r10,#1) // loop count is 1 more than shift count
r13:12 = lsl(r5:4,r10) // shift divisor msb into same bit position as dividend msb
r15:14 = lsl(r15:14,r10) // shift the bit left by same amount as divisor
}
{
p0 = cmp.gtu(r5:4,r3:2) // check if divisor > dividend
loop0(1f,r11) // register loop
}
{
if (p0) jump .hexagon_divdi3_return // if divisor > dividend, we're done, so return
}
.falign
1:
{
p0 = cmp.gtu(r13:12,r3:2) // set predicate reg if shifted divisor > current remainder
}
{
r7:6 = sub(r3:2, r13:12) // subtract shifted divisor from current remainder
r9:8 = add(r1:0, r15:14) // save current quotient to temp (r9:8)
}
{
r1:0 = vmux(p0, r1:0, r9:8) // choose either current quotient or new quotient (r9:8)
r3:2 = vmux(p0, r3:2, r7:6) // choose either current remainder or new remainder (r7:6)
}
{
r15:14 = lsr(r15:14, #1) // shift bit right by 1 for next iteration
r13:12 = lsr(r13:12, #1) // shift "shifted divisor" right by 1 for next iteration
}:endloop0
.hexagon_divdi3_return:
{
r3:2 = neg(r1:0)
}
{
r1:0 = vmux(p3,r3:2,r1:0)
jumpr r31
}
FUNCTION_END __hexagon_divdi3
.globl __qdsp_divdi3
.set __qdsp_divdi3, __hexagon_divdi3
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