/*
	This C language subroutine converts and ascii string
	to a floating point value.
	
	The Run Time Library for the C Language.

	Gordon A. Sterling	(617) 461 - 3076
	DSP Development Tools Engineering

	Created on 12/12/92
	Altered on 1/95 by AS - separated polymorphism

	#include <stdlib.h>		<Header>
	double atof(pm char *p);	<Prototype>
*/

#include "lib_glob.h"
#include "sdl_glob.h"

.SEGMENT/CODE	Code_Space_Name;
.FILE 		RTL_FILENAME;

.GLOBAL	    	___atofP;

___atofP:	
atof_core:	put(R2);
		R2=MR2F;
		put(R2);
		R2=MR1F;
		put(R2);
		R2=MR0F;
		put(R2);
		put(R3);
		put(R5);
		put(R6);
		put(R7);
		put(R9);
		put(R10);
		put(R11);
		put(R13);
		put(R14);
		put(R15);
		
pm_atof:	R12=R12-R12, pm_ptr=R4;	/* Clr out acc regs, Pt to str*/
		R13=R13-R13, pm_lnt=R12; /* Clear out LSW acc	*/
		R7=R7-R7, dm_lnt=R12;	/* Used for sign value	*/

		R10=32;			/*  32 = ASC(' ')	*/
		R9=13;			/*  13 = ASC('/n')	*/
		R8=9;			/*   9 = ASC('/r')	*/

clean_pspaces:	R11=PM(pm_ptr,pm_1);	/* Read character	*/
		COMP(R11,R10);		/* Compare to ' '	*/
		IF EQ JUMP (PC, clean_pspaces);/* Remove more spaces*/
		COMP(R11,R9);		/* Compare to '/n'	*/
		IF GT JUMP (PC, acc_psign); /* Check for number	*/
		COMP(R11,R8);		/* Compare to '/r'	*/
		IF GE JUMP (PC, clean_pspaces);/* Remove more spaces*/

acc_psign:	R10=43;			/*  43 = ASC('+')	*/
		R9=45;			/*  45 = ASC('-')	*/
		COMP(R11,R10);		/* Compare to '+'	*/
		IF EQ R7=R7-R7, R11=PM(pm_ptr,pm_1);/* Sign is positive	*/
		COMP(R11,R9);		/* Compare to '-'	*/
		IF EQ R7=R7-1, R11=PM(pm_ptr,pm_1);/* Sign is negative	*/

acc_pnum:	dm_mdf=R7;		/* Hold sign for now	*/
		R10=46;			/*  46 = ASC('.')	*/
		R9=101;			/* 101 = ASC('e')	*/
		R8=69;			/*  69 = ASC('E')	*/
		R7=57;			/*  57 = ASC('9')	*/
		R6=48;			/*  48 = ASC('0')	*/

		F14=0x40240000;		/* MSW of 10.0		*/

acc_pint:	COMP(R11,R10);		/* Compare to '.'	*/
		IF EQ JUMP (PC, acc_pfract); /* Accumulate fraction*/
		COMP(R11,R9);		/* Compare to 'e'	*/
		IF EQ JUMP (PC, acc_pexp); /* Get exponent	*/
		COMP(R11,R8);		/* Compare to 'E'	*/
		IF EQ JUMP (PC, acc_pexp); /* Get exponent	*/
		COMP(R11,R7);		/* Compare to '9'	*/
		IF GT JUMP (PC, non_num); /* Not a number, end	*/
		COMP(R11,R6);		/* Compare to '0'	*/
		IF LT JUMP (PC, non_num); /* Not a number, end it*/
		CALL (PC, ___lib_dmult) (DB);	/* Multiply sum by 10.0	*/
		R15=R15-R15;		/* Zero out LSW of 10.0	*/
		NOP;			/* DEAD CYCLE		*/

		CALL (PC, ___lib_itod) (DB);	/* Convert number to dbl*/
		R12=PASS R0, R13=R1;	/* Hold sum		*/
		R0=R11-R6;		/* Convert number to int*/

		CALL (PC, ___lib_dadd) (DB);	/* Add to sum	*/
		R11=PASS R14;		/* Hold MSW of 10.0	*/
		R14=PASS R0, R15=R1;	/* Copy num for add	*/	

		JUMP (PC, acc_pint) (DB);	/* Get next character*/
		R12=PASS R0, R13=R1;	/* Copy current sum	*/
		R14=PASS R11, R11=PM(pm_ptr,pm_1);/* Copy MSW of 10.0 */

acc_pfract:	R14=0x3ff00000;		/* MSW of 1.0		*/
		R15=0;			/* LSW of 1.0		*/

get_nextpfract:	R11=PM(pm_ptr,pm_1);
		COMP(R11,R9);		/* Compare to 'e'	*/
		IF EQ JUMP (PC, acc_pexp); /* Get exponent	*/
		COMP(R11,R8);		/* Compare to 'E'	*/
		IF EQ JUMP (PC, acc_pexp); /* Get exponent	*/
		COMP(R11,R7);		/* Compare to '9'	*/
		IF GT JUMP (PC, non_num); /* Not a number, end	*/
		COMP(R11,R6);		/* Compare to '0'	*/
		IF LT JUMP (PC, non_num); /* Not a number, end it*/
		CALL (PC, ___lib_itod) (DB);/* Convert number to dbl*/
		R0=R11-R6;		/* Convert to num first	*/
		R10=0x3fb99999;		/* Load MSW of 0.1	*/

		R1=0x9999999a;		/* Load LSW of 0.1	*/
		R11=R0;			/* Hold MSW of num	*/
		CALL (PC, ___lib_dmult) (DB); /* Multiply fract by .1*/
		R4=PASS R12, R5=R13;	/* Hold sum		*/
		R13=PASS R1, R12=R10;	/* Copy number		*/

		CALL (PC, ___lib_dmult) (DB); /* Multiply num by fract*/
		R14=PASS R0, R15=R1;	/* Hold fractional part	*/
		R13=R13-R13, R12=R11;	/* Copy current number	*/

		R10=PASS R14, R11=R15;	/* Hold current fract	*/
		CALL (PC, ___lib_dadd) (DB); /* Add to current sum*/
		R14=PASS R0, R15=R1;	/* Move for add		*/
		R12=PASS R4, R13=R5;	/* Copy old sum		*/

		JUMP (PC, get_nextpfract) (DB);/* Get next number*/
		R12=PASS R0, R13=R1;	/* Copy current sum	*/
		R14=PASS R10, R15=R11;	/* Copy current fract	*/

acc_pexp:	R8=R8-R8, R11=PM(pm_ptr,pm_1);/*For exp sign,Rd 1st expr part*/
		R10=43;			/*  43 = ASC('+')	*/
		R9=45;			/*  45 = ASC('-')	*/
		COMP(R11,R10);		/* Compare to '+'	*/
		IF EQ R8=R8-R8, R11=PM(pm_ptr,pm_1);/* Sign is positive	*/
		COMP(R11,R9);		/* Compare to '-'	*/
		IF EQ R8=R8-1, R11=PM(pm_ptr,pm_1);/* Sign is negative	*/
		R9=0;			/* Clear sum		*/
		R10=10;			/* Used for multiply	*/

get_next_pexp:	COMP(R11,R7);		/* Compare to '9'	*/
		IF GT JUMP (PC, got_exp); /* Not a number, end	*/
		COMP(R11,R6);		/* Compare to '0'	*/
		IF LT JUMP (PC, got_exp); /* Not a number, end it*/
		R11=R11-R6;		/* Get number		*/
		JUMP (PC, get_next_pexp) (DB);/* Get next number*/
		R9=R9*R10 (SSI);	/* Mult sum by 10	*/
		R9=R9+R11, R11=PM(pm_ptr,pm_1);	/* Add to sum	*/

compute_exp:	CALL (PC, ___lib_dmult) (DB);	/* Multiply sum by exp	*/
		R12=PASS R0, R13=R1;	/* Copy exp value	*/
		R14=PASS R10, R15=R11;	/* Copy old sum		*/
		
restore_state:	get(R15,1);
		get(R14,2);
		get(R13,3);
		get(R11,4);
		get(R10,5);
		get(R9,6);
		get(R7,7);
		get(R6,8);
		get(R5,9);
		FETCH_RETURN
		get(R2,11);
		MR0F=R2, get(R2,12);
		MR1F=R2, get(R2,13);
		MR2F=R2, get(R3,10);
		RETURN (DB);
		RESTORE_STACK
		RESTORE_FRAME

.ENDSEG;