vlop_386.s

Documentation: runtime

     1  // Inferno's libkern/vlop-386.s
     2  // https://bitbucket.org/inferno-os/inferno-os/src/master/libkern/vlop-386.s
     3  //
     4  //         Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
     5  //         Revisions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com).  All rights reserved.
     6  //         Portions Copyright 2009 The Go Authors. All rights reserved.
     7  //
     8  // Permission is hereby granted, free of charge, to any person obtaining a copy
     9  // of this software and associated documentation files (the "Software"), to deal
    10  // in the Software without restriction, including without limitation the rights
    11  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    12  // copies of the Software, and to permit persons to whom the Software is
    13  // furnished to do so, subject to the following conditions:
    14  //
    15  // The above copyright notice and this permission notice shall be included in
    16  // all copies or substantial portions of the Software.
    17  //
    18  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    19  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    20  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
    21  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    22  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    23  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    24  // THE SOFTWARE.
    25  
    26  #include "textflag.h"
    27  
    28  /*
    29   * C runtime for 64-bit divide.
    30   */
    31  
    32  // runtime·_mul64x32(lo64 *uint64, a uint64, b uint32) (hi32 uint32)
    33  // sets *lo64 = low 64 bits of 96-bit product a*b; returns high 32 bits.
    34  TEXT runtime·_mul64by32(SB), NOSPLIT, $0
    35  	MOVL	lo64+0(FP), CX
    36  	MOVL	a_lo+4(FP), AX
    37  	MULL	b+12(FP)
    38  	MOVL	AX, 0(CX)
    39  	MOVL	DX, BX
    40  	MOVL	a_hi+8(FP), AX
    41  	MULL	b+12(FP)
    42  	ADDL	AX, BX
    43  	ADCL	$0, DX
    44  	MOVL	BX, 4(CX)
    45  	MOVL	DX, AX
    46  	MOVL	AX, hi32+16(FP)
    47  	RET
    48  
    49  TEXT runtime·_div64by32(SB), NOSPLIT, $0
    50  	MOVL	r+12(FP), CX
    51  	MOVL	a_lo+0(FP), AX
    52  	MOVL	a_hi+4(FP), DX
    53  	DIVL	b+8(FP)
    54  	MOVL	DX, 0(CX)
    55  	MOVL	AX, q+16(FP)
    56  	RET
    57
View as plain text