//
// The iterative method processes n Words by n divW() calls, each of which visits every Word in the
// incrementally shortened q for a total of n + (n-1) + (n-2) ... + 2 + 1, or n(n+1)/2 divW()'s.
// Recursive conversion divides q by its approximate square root, yielding two parts, each half
// the size of q. Using the iterative method on both halves means 2 * (n/2)(n/2 + 1)/2 divW()'s

Harshavardhana <******@****.***> 1712330228 -0700

Harshavardhana <******@****.***> 1712330228 -0700

	// nano/100 = DX:AX
	// split into two decimal halves by div 1e9.
	// (decimal point is two spots over from correct place,
	// but we avoid overflow in the high word.)
	MOVL	$1000000000, CX
	DIVL	CX
	MOVL	AX, DI
	MOVL	DX, SI

	// DI = nano/100/1e9 = nano/1e11 = sec/100, DX = SI = nano/100%1e9
	// split DX into seconds and nanoseconds by div 1e7 magic multiply.
	MOVL	DX, AX
	MOVL	$1801439851, CX
	MULL	CX

	ADDL	AX, BX
	ADCL	$0, DX
	MOVL	BX, 4(CX)
	MOVL	DX, AX
	MOVL	AX, hi32+16(FP)
	RET

TEXT runtime·_div64by32(SB), NOSPLIT, $0
	MOVL	r+12(FP), CX
	MOVL	a_lo+0(FP), AX
	MOVL	a_hi+4(FP), DX
	DIVL	b+8(FP)
	MOVL	DX, 0(CX)
	MOVL	AX, q+16(FP)

              (MHLO_AddOp
                (MHLO_DivOp:$div
                  (MHLO_SubtractOp $arg0, $rem2),
                  $arg1b),
                (MHLO_ConstantOp $cst_neg1)),
              $div1)),
          (TF_FloorDivOp $arg0, $arg1),
          [(ValueEquals<"0.0"> $cst),
           (ValueEquals<"-1.0"> $cst_neg1),
           (SameValue $div, $div1),
           (SameValue $rem, $rem1),

(Div64 x y) => (DIVV x y)
(Div64u ...) => (DIVVU ...)
(Div32 x y) => (DIVV (SignExt32to64 x) (SignExt32to64 y))
(Div32u x y) => (DIVVU (ZeroExt32to64 x) (ZeroExt32to64 y))
(Div16 x y) => (DIVV (SignExt16to64 x) (SignExt16to64 y))
(Div16u x y) => (DIVVU (ZeroExt16to64 x) (ZeroExt16to64 y))
(Div8 x y) => (DIVV (SignExt8to64 x) (SignExt8to64 y))

	MULU	R21, R13	// 01b50019
	MULV	R19, R8		// 0113001c
	MULVU	R21, R13	// 01b5001d

//	LDIV rreg ',' rreg
//	{
//		outcode(int($1), &$2, 0, &$4);
//	}
	DIV	R18, R22	// 02d2001a
	DIVU	R14, R9		// 012e001b
	DIVV	R8, R13		// 01a8001e
	DIVVU	R16, R19	// 0270001f

//	LREM rreg ',' rreg
//	{
//		outcode(int($1), &$2, 0, &$4);
//	}
	REM	R18, R22	// 02d2001a
	REMU	R14, R9		// 012e001b

	{VNMLA_EQ_F64, []int{2, 1, 0}, "VNMLA", "NMULAD"},
	{VNMLS_EQ_F32, []int{2, 1, 0}, "VNMLS", "NMULSF"},
	{VNMLS_EQ_F64, []int{2, 1, 0}, "VNMLS", "NMULSD"},
	{VDIV_EQ_F32, []int{2, 1, 0}, "VDIV", "DIVF"},
	{VDIV_EQ_F64, []int{2, 1, 0}, "VDIV", "DIVD"},
	{VNEG_EQ_F32, []int{1, 0}, "VNEG", "NEGF"},
	{VNEG_EQ_F64, []int{1, 0}, "VNEG", "NEGD"},
	{VABS_EQ_F32, []int{1, 0}, "VABS", "ABSF"},
	{VABS_EQ_F64, []int{1, 0}, "VABS", "ABSD"},

    adjust -= ROW + 2*PADDING;  // Room for details

    const divs = [];
    for (const box of list) {
      box.y -= adjust;
      divs.push(drawBox(xscale, box));
    }
    divs.push(drawSep(-adjust, posTotal, negTotal));

    const h = (list.length > 0 ?  list[list.length-1].y : 0) + 4*ROW;
    chart.style.height = h+'px';
    chart.replaceChildren(...divs);
  }

  function drawBox(xscale, box) {