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// Copyright ©2016 The Gonum Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !noasm,!gccgo,!safe
#include "textflag.h"
// func DivTo(dst, x, y []float64)
TEXT ·DivTo(SB), NOSPLIT, $0
MOVQ dst_base+0(FP), DI // DI = &dst
MOVQ dst_len+8(FP), CX // CX = len(dst)
MOVQ x_base+24(FP), SI // SI = &x
MOVQ y_base+48(FP), DX // DX = &y
CMPQ x_len+32(FP), CX // CX = max( len(dst), len(x), len(y) )
CMOVQLE x_len+32(FP), CX
CMPQ y_len+56(FP), CX
CMOVQLE y_len+56(FP), CX
MOVQ CX, ret_len+80(FP) // len(ret) = CX
CMPQ CX, $0 // if CX == 0 { return }
JE div_end
XORQ AX, AX // i = 0
MOVQ DX, BX
ANDQ $15, BX // BX = &y & OxF
JZ div_no_trim // if BX == 0 { goto div_no_trim }
// Align on 16-bit boundary
MOVSD (SI)(AX*8), X0 // X0 = s[i]
DIVSD (DX)(AX*8), X0 // X0 /= t[i]
MOVSD X0, (DI)(AX*8) // dst[i] = X0
INCQ AX // ++i
DECQ CX // --CX
JZ div_end // if CX == 0 { return }
div_no_trim:
MOVQ CX, BX
ANDQ $7, BX // BX = len(dst) % 8
SHRQ $3, CX // CX = floor( len(dst) / 8 )
JZ div_tail_start // if CX == 0 { goto div_tail_start }
div_loop: // Loop unrolled 8x do {
MOVUPS (SI)(AX*8), X0 // X0 = x[i:i+1]
MOVUPS 16(SI)(AX*8), X1
MOVUPS 32(SI)(AX*8), X2
MOVUPS 48(SI)(AX*8), X3
DIVPD (DX)(AX*8), X0 // X0 /= y[i:i+1]
DIVPD 16(DX)(AX*8), X1
DIVPD 32(DX)(AX*8), X2
DIVPD 48(DX)(AX*8), X3
MOVUPS X0, (DI)(AX*8) // dst[i:i+1] = X0
MOVUPS X1, 16(DI)(AX*8)
MOVUPS X2, 32(DI)(AX*8)
MOVUPS X3, 48(DI)(AX*8)
ADDQ $8, AX // i += 8
LOOP div_loop // } while --CX > 0
CMPQ BX, $0 // if BX == 0 { return }
JE div_end
div_tail_start: // Reset loop registers
MOVQ BX, CX // Loop counter: CX = BX
div_tail: // do {
MOVSD (SI)(AX*8), X0 // X0 = x[i]
DIVSD (DX)(AX*8), X0 // X0 /= y[i]
MOVSD X0, (DI)(AX*8)
INCQ AX // ++i
LOOP div_tail // } while --CX > 0
div_end:
MOVQ DI, ret_base+72(FP) // &ret = &dst
MOVQ dst_cap+16(FP), DI // cap(ret) = cap(dst)
MOVQ DI, ret_cap+88(FP)
RET
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