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coherent

/////////
/
/ Shift left.
/ Small shifts (1 or 2 bits) are easy.
/ Longer shifts use either 'shift by CL' (words) or a loop (longs).
/ Shifts by a constant generate the load of CL directly
/ to get a 'movb' instruction and save a byte.
/
/////////

SHL:
%	PEFFECT|PRVALUE|PREL|P_SLT|P80186
	WORD		ANYR	ANYR	*	TEMP
		TREG		WORD
		BYTE|MMX	WORD
%	PLVALUE|P_SLT|P80186
	WORD		ANYL	ANYL	*	TEMP
		TREG		WORD
		BYTE|MMX	WORD
			[ZSAL]	[R],[AR]
		[IFR]	[REL0]	[LAB]

%	PEFFECT|PRVALUE|PREL|P_SLT
	WORD		ANYR	ANYR	*	TEMP
		TREG		WORD
		1|MMX		*
%	PLVALUE|P_SLT
	WORD		ANYL	ANYL	*	TEMP
		TREG		WORD
		1|MMX		*
			[ZSAL]	[R],[AR]
		[IFR]	[REL0]	[LAB]

%	PEFFECT|PRVALUE|PREL|P_SLT
	WORD		ANYR	ANYR	*	TEMP
		TREG		WORD
		2|MMX		*
%	PLVALUE|P_SLT
	WORD		ANYL	ANYL	*	TEMP
		TREG		WORD
		2|MMX		*
			[ZSAL]	[R],[CONST 1]
			[ZSAL]	[R],[CONST 1]
		[IFR]	[REL0]	[LAB]

/////////
/
/ Harder word shifts.
/ If the right is a constant,
/ use a MOVB to load the shift count and save a byte.
/
/////////
%	PEFFECT|PRVALUE|PREL|P_SLT
	WORD		ANYR	ANYR	CX	TEMP
		TREG		WORD
		IMM|MMX		WORD
%	PLVALUE|P_SLT
	WORD		ANYL	ANYL	CX	TEMP
		TREG		WORD
		IMM|MMX		WORD
			[ZMOVB]	[REGNO CL],[AR]
			[ZSAL]	[R],[REGNO CL]
		[IFR]	[REL0]	[LAB]

%	PEFFECT|PRVALUE|P_SLT
	WORD		ANYR	ANYR	CX	TEMP
		TREG		WORD
		ADR		WORD
%	PLVALUE|P_SLT
	WORD		ANYL	ANYL	CX	TEMP
		TREG		WORD
		ADR		WORD
			[ZMOV]	[REGNO CX],[AR]
			[ZSAL]	[R],[REGNO CL]

/////////
/
/ Hard long shifts.
/ Since the modify phase has ripped out shifts by 0,
/ any immediate shift is by a nonzero count, so no JCXZ is needed.
/
/////////

%	PEFFECT|PRVALUE|P_SLT
	LONG		DXAX	DXAX	CX	DXAX
		TREG		LONG
		IMM|MMX		WORD
			[ZMOV]	[REGNO CX],[AR]
		[DLAB0]:[ZSAL]	[LO R],[CONST 1]
			[ZRCL]	[HI R],[CONST 1]
			[ZLOOP]	[LAB0]

%	PEFFECT|PRVALUE|P_SLT
	LONG		DXAX	DXAX	CX	DXAX
		TREG		LONG
		ADR		WORD
			[ZMOV]	[REGNO CX],[AR]
			[ZJCXZ]	[LAB0]
		[DLAB1]:[ZSAL]	[LO R],[CONST 1]
			[ZRCL]	[HI R],[CONST 1]
			[ZLOOP]	[LAB1]
		[DLAB0]:

/////////
/
/ These strange entries are for LARGE model int-to-pointer conversions.
/ The pointer is a strange kind of long integer.
/ Computes the word into the offset, does the shift
/ and sets the base to 0.
/
/////////

#ifndef ONLYSMALL
%	PEFFECT|PRVALUE|P80186
	LPTX		DXAX	AX	*	DXAX
		TREG		WORD
		BYTE|MMX	WORD
			[ZSAL]	[LO R],[AR]
			[ZSUB]	[HI R],[HI R]

%	PEFFECT|PRVALUE
	LPTX		DXAX	AX	CX	DXAX
		TREG		WORD
		IMM|MMX		WORD
			[ZMOVB]	[REGNO CL],[AR]
			[ZSAL]	[LO R],[REGNO CL]
			[ZSUB]	[HI R],[HI R]

%	PEFFECT|PRVALUE
	LPTX		DXAX	AX	CX	DXAX
		TREG		WORD
		ADR		WORD
			[ZMOV]	[REGNO CX],[AR]
			[ZSAL]	[LO R],[REGNO CL]
			[ZSUB]	[HI R],[HI R]
#endif

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