Subversion Repositories planix.SVN

TEXT ptclbsum(SB), $0
        MOVL    addr+0(FP), SI
        MOVL    len+4(FP), CX

        XORL    AX, AX                  /* sum */

        TESTL   $1, SI                  /* byte aligned? */
        MOVL    SI, DI
        JEQ     _2align

        DECL    CX
        JLT     _return

        MOVB    0x00(SI), AH
        INCL    SI

_2align:
        TESTL   $2, SI                  /* word aligned? */
        JEQ     _32loop

        CMPL    CX, $2                  /* less than 2 bytes? */
        JLT     _1dreg
        SUBL    $2, CX

        XORL    BX, BX
        MOVW    0x00(SI), BX
        ADDL    BX, AX
        ADCL    $0, AX
        LEAL    2(SI), SI

_32loop:
        CMPL    CX, $0x20
        JLT     _8loop

        MOVL    CX, BP
        SHRL    $5, BP
        ANDL    $0x1F, CX

_32loopx:
        MOVL    0x00(SI), BX
        MOVL    0x1C(SI), DX
        ADCL    BX, AX
        MOVL    0x04(SI), BX
        ADCL    DX, AX
        MOVL    0x10(SI), DX
        ADCL    BX, AX
        MOVL    0x08(SI), BX
        ADCL    DX, AX
        MOVL    0x14(SI), DX
        ADCL    BX, AX
        MOVL    0x0C(SI), BX
        ADCL    DX, AX
        MOVL    0x18(SI), DX
        ADCL    BX, AX
        LEAL    0x20(SI), SI
        ADCL    DX, AX

        DECL    BP
        JNE     _32loopx

        ADCL    $0, AX

_8loop:
        CMPL    CX, $0x08
        JLT     _2loop

        MOVL    CX, BP
        SHRL    $3, BP
        ANDL    $0x07, CX

_8loopx:
        MOVL    0x00(SI), BX
        ADCL    BX, AX
        MOVL    0x04(SI), DX
        ADCL    DX, AX

        LEAL    0x08(SI), SI
        DECL    BP
        JNE     _8loopx

        ADCL    $0, AX

_2loop:
        CMPL    CX, $0x02
        JLT     _1dreg

        MOVL    CX, BP
        SHRL    $1, BP
        ANDL    $0x01, CX

_2loopx:
        MOVWLZX 0x00(SI), BX
        ADCL    BX, AX

        LEAL    0x02(SI), SI
        DECL    BP
        JNE     _2loopx

        ADCL    $0, AX

_1dreg:
        TESTL   $1, CX                  /* 1 byte left? */
        JEQ     _fold

        XORL    BX, BX
        MOVB    0x00(SI), BX
        ADDL    BX, AX
        ADCL    $0, AX

_fold:
        MOVL    AX, BX
        SHRL    $16, BX
        JEQ     _swab

        ANDL    $0xFFFF, AX
        ADDL    BX, AX
        JMP     _fold

_swab:
        TESTL   $1, addr+0(FP)
        /*TESTL $1, DI*/
        JNE     _return
        XCHGB   AH, AL

_return:
        RET