Initial revision

1 files changed, 511 insertions, 0 deletions

diff --git a/gas/config/atof-ieee.c b/gas/config/atof-ieee.c
new file mode 100644
index 0000000..323d4e1
--- /dev/null
+++ b/gas/config/atof-ieee.c
@@ -0,0 +1,511 @@
+/* atof_ieee.c - turn a Flonum into an IEEE floating point number
+   Copyright (C) 1987 Free Software Foundation, Inc.
+
+This file is part of GAS, the GNU Assembler.
+
+GAS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 1, or (at your option)
+any later version.
+
+GAS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GAS; see the file COPYING.  If not, write to
+the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+#include "as.h"
+
+#ifdef USG
+#define bzero(s,n) memset(s,0,n)
+#define bcopy(from,to,n) memcpy((to),(from),(n))
+#endif
+
+extern FLONUM_TYPE generic_floating_point_number; /* Flonums returned here. */
+
+#ifndef NULL
+#define NULL (0)
+#endif
+
+extern char EXP_CHARS[];
+				/* Precision in LittleNums. */
+#define MAX_PRECISION (6)
+#define F_PRECISION (2)
+#define D_PRECISION (4)
+#define X_PRECISION (6)
+#define P_PRECISION (6)
+
+				/* Length in LittleNums of guard bits. */
+#define GUARD (2)
+
+static unsigned long mask [] = {
+  0x00000000,
+  0x00000001,
+  0x00000003,
+  0x00000007,
+  0x0000000f,
+  0x0000001f,
+  0x0000003f,
+  0x0000007f,
+  0x000000ff,
+  0x000001ff,
+  0x000003ff,
+  0x000007ff,
+  0x00000fff,
+  0x00001fff,
+  0x00003fff,
+  0x00007fff,
+  0x0000ffff,
+  0x0001ffff,
+  0x0003ffff,
+  0x0007ffff,
+  0x000fffff,
+  0x001fffff,
+  0x003fffff,
+  0x007fffff,
+  0x00ffffff,
+  0x01ffffff,
+  0x03ffffff,
+  0x07ffffff,
+  0x0fffffff,
+  0x1fffffff,
+  0x3fffffff,
+  0x7fffffff,
+  0xffffffff
+  };
+
+
+static int bits_left_in_littlenum;
+static int littlenums_left;
+static LITTLENUM_TYPE *littlenum_pointer;
+
+static int
+next_bits (number_of_bits)
+     int		number_of_bits;
+{
+  int			return_value;
+
+  if(!littlenums_left)
+  	return 0;
+  if (number_of_bits >= bits_left_in_littlenum)
+    {
+      return_value  = mask [bits_left_in_littlenum] & *littlenum_pointer;
+      number_of_bits -= bits_left_in_littlenum;
+      return_value <<= number_of_bits;
+      if(--littlenums_left) {
+	      bits_left_in_littlenum = LITTLENUM_NUMBER_OF_BITS - number_of_bits;
+	      littlenum_pointer --;
+	      return_value |= (*littlenum_pointer>>bits_left_in_littlenum) & mask[number_of_bits];
+      }
+    }
+  else
+    {
+      bits_left_in_littlenum -= number_of_bits;
+      return_value = mask [number_of_bits] & (*littlenum_pointer>>bits_left_in_littlenum);
+    }
+  return (return_value);
+}
+
+/* Num had better be less than LITTLENUM_NUMBER_OF_BITS */
+static void
+unget_bits(num)
+int num;
+{
+	if(!littlenums_left) {
+		++littlenum_pointer;
+		++littlenums_left;
+		bits_left_in_littlenum=num;
+	} else if(bits_left_in_littlenum+num>LITTLENUM_NUMBER_OF_BITS) {
+		bits_left_in_littlenum= num-(LITTLENUM_NUMBER_OF_BITS-bits_left_in_littlenum);
+		++littlenum_pointer;
+		++littlenums_left;
+	} else
+		bits_left_in_littlenum+=num;
+}
+
+static void
+make_invalid_floating_point_number (words)
+     LITTLENUM_TYPE *	words;
+{
+	as_bad("cannot create floating-point number");
+	words[0]= ((unsigned)-1)>>1;	/* Zero the leftmost bit */
+	words[1]= -1;
+	words[2]= -1;
+	words[3]= -1;
+	words[4]= -1;
+	words[5]= -1;
+}
+
+/***********************************************************************\
+*	Warning: this returns 16-bit LITTLENUMs. It is up to the caller	*
+*	to figure out any alignment problems and to conspire for the	*
+*	bytes/word to be emitted in the right order. Bigendians beware!	*
+*									*
+\***********************************************************************/
+
+/* Note that atof-ieee always has X and P precisions enabled.  it is up
+   to md_atof to filter them out if the target machine does not support
+   them.  */
+
+char *				/* Return pointer past text consumed. */
+atof_ieee (str, what_kind, words)
+     char *		str;	/* Text to convert to binary. */
+     char		what_kind; /* 'd', 'f', 'g', 'h' */
+     LITTLENUM_TYPE *	words;	/* Build the binary here. */
+{
+	static LITTLENUM_TYPE	bits [MAX_PRECISION + MAX_PRECISION + GUARD];
+				/* Extra bits for zeroed low-order bits. */
+				/* The 1st MAX_PRECISION are zeroed, */
+				/* the last contain flonum bits. */
+	char *		return_value;
+	int		precision; /* Number of 16-bit words in the format. */
+	long	exponent_bits;
+
+	return_value = str;
+	generic_floating_point_number.low	= bits + MAX_PRECISION;
+	generic_floating_point_number.high	= NULL;
+	generic_floating_point_number.leader	= NULL;
+	generic_floating_point_number.exponent	= NULL;
+	generic_floating_point_number.sign	= '\0';
+
+				/* Use more LittleNums than seems */
+				/* necessary: the highest flonum may have */
+				/* 15 leading 0 bits, so could be useless. */
+
+	bzero (bits, sizeof(LITTLENUM_TYPE) * MAX_PRECISION);
+
+	switch(what_kind) {
+	case 'f':
+	case 'F':
+	case 's':
+	case 'S':
+		precision = F_PRECISION;
+		exponent_bits = 8;
+		break;
+
+	case 'd':
+	case 'D':
+	case 'r':
+	case 'R':
+		precision = D_PRECISION;
+		exponent_bits = 11;
+		break;
+
+	case 'x':
+	case 'X':
+	case 'e':
+	case 'E':
+		precision = X_PRECISION;
+		exponent_bits = 15;
+		break;
+
+	case 'p':
+	case 'P':
+		
+		precision = P_PRECISION;
+		exponent_bits= -1;
+		break;
+
+	default:
+		make_invalid_floating_point_number (words);
+		return NULL;
+	}
+
+	generic_floating_point_number.high = generic_floating_point_number.low + precision - 1 + GUARD;
+
+	if (atof_generic (& return_value, ".", EXP_CHARS, & generic_floating_point_number)) {
+		/* as_bad("Error converting floating point number (Exponent overflow?)"); */
+		make_invalid_floating_point_number (words);
+		return NULL;
+	}
+	gen_to_words(words, precision, exponent_bits);
+	return return_value;
+}
+
+/* Turn generic_floating_point_number into a real float/double/extended */
+int gen_to_words(words, precision, exponent_bits)
+LITTLENUM_TYPE *words;
+int precision;
+long exponent_bits;
+{
+	int return_value=0;
+
+	long	exponent_1;
+	long	exponent_2;
+	long	exponent_3;
+	long	exponent_4;
+	int		exponent_skippage;
+	LITTLENUM_TYPE	word1;
+	LITTLENUM_TYPE *	lp;
+
+	if (generic_floating_point_number.low > generic_floating_point_number.leader) {
+		/* 0.0e0 seen. */
+		if(generic_floating_point_number.sign=='+')
+			words[0]=0x0000;
+		else
+			words[0]=0x8000;
+		bzero (&words[1], sizeof(LITTLENUM_TYPE) * (precision-1));
+		return return_value;
+	}
+
+	/* NaN:  Do the right thing */
+	if(generic_floating_point_number.sign==0) {
+		if(precision==F_PRECISION) {
+			words[0]=0x7fff;
+			words[1]=0xffff;
+		} else {
+			words[0]=0x7fff;
+			words[1]=0xffff;
+			words[2]=0xffff;
+			words[3]=0xffff;
+		}
+		return return_value;
+	} else if(generic_floating_point_number.sign=='P') {
+		/* +INF:  Do the right thing */
+		if(precision==F_PRECISION) {
+			words[0]=0x7f80;
+			words[1]=0;
+		} else {
+			words[0]=0x7ff0;
+			words[1]=0;
+			words[2]=0;
+			words[3]=0;
+		}
+		return return_value;
+	} else if(generic_floating_point_number.sign=='N') {
+		/* Negative INF */
+		if(precision==F_PRECISION) {
+			words[0]=0xff80;
+			words[1]=0x0;
+		} else {
+			words[0]=0xfff0;
+			words[1]=0x0;
+			words[2]=0x0;
+			words[3]=0x0;
+		}
+		return return_value;
+	}
+		/*
+		 * The floating point formats we support have:
+		 * Bit 15 is sign bit.
+		 * Bits 14:n are excess-whatever exponent.
+		 * Bits n-1:0 (if any) are most significant bits of fraction.
+		 * Bits 15:0 of the next word(s) are the next most significant bits.
+		 *
+		 * So we need: number of bits of exponent, number of bits of
+		 * mantissa.
+		 */
+	bits_left_in_littlenum = LITTLENUM_NUMBER_OF_BITS;
+	littlenum_pointer = generic_floating_point_number.leader;
+	littlenums_left = 1+generic_floating_point_number.leader - generic_floating_point_number.low;
+	/* Seek (and forget) 1st significant bit */
+	for (exponent_skippage = 0;! next_bits(1); exponent_skippage ++)
+		;
+	exponent_1 = generic_floating_point_number.exponent + generic_floating_point_number.leader + 1 -
+ generic_floating_point_number.low;
+	/* Radix LITTLENUM_RADIX, point just higher than generic_floating_point_number.leader. */
+	exponent_2 = exponent_1 * LITTLENUM_NUMBER_OF_BITS;
+	/* Radix 2. */
+	exponent_3 = exponent_2 - exponent_skippage;
+	/* Forget leading zeros, forget 1st bit. */
+	exponent_4 = exponent_3 + ((1 << (exponent_bits - 1)) - 2);
+	/* Offset exponent. */
+
+	lp = words;
+
+	/* Word 1. Sign, exponent and perhaps high bits. */
+	word1 =   (generic_floating_point_number.sign == '+') ? 0 : (1<<(LITTLENUM_NUMBER_OF_BITS-1));
+
+	/* Assume 2's complement integers. */
+	if(exponent_4<1 && exponent_4>=-62) {
+		int prec_bits;
+		int num_bits;
+
+		unget_bits(1);
+		num_bits= -exponent_4;
+		prec_bits=LITTLENUM_NUMBER_OF_BITS*precision-(exponent_bits+1+num_bits);
+		if(precision==X_PRECISION && exponent_bits==15)
+			prec_bits-=LITTLENUM_NUMBER_OF_BITS+1;
+
+		if(num_bits>=LITTLENUM_NUMBER_OF_BITS-exponent_bits) {
+			/* Bigger than one littlenum */
+			num_bits-=(LITTLENUM_NUMBER_OF_BITS-1)-exponent_bits;
+			*lp++=word1;
+			if(num_bits+exponent_bits+1>=precision*LITTLENUM_NUMBER_OF_BITS) {
+				/* Exponent overflow */
+				make_invalid_floating_point_number(words);
+				return return_value;
+			}
+			if(precision==X_PRECISION && exponent_bits==15) {
+				*lp++=0;
+				*lp++=0;
+				num_bits-=LITTLENUM_NUMBER_OF_BITS-1;
+			}
+			while(num_bits>=LITTLENUM_NUMBER_OF_BITS) {
+				num_bits-=LITTLENUM_NUMBER_OF_BITS;
+				*lp++=0;
+			}
+			if(num_bits)
+				*lp++=next_bits(LITTLENUM_NUMBER_OF_BITS-(num_bits));
+		} else {
+			if(precision==X_PRECISION && exponent_bits==15) {
+				*lp++=word1;
+				*lp++=0;
+				if(num_bits==LITTLENUM_NUMBER_OF_BITS) {
+					*lp++=0;
+					*lp++=next_bits(LITTLENUM_NUMBER_OF_BITS-1);
+				} else if(num_bits==LITTLENUM_NUMBER_OF_BITS-1)
+					*lp++=0;
+				else
+					*lp++=next_bits(LITTLENUM_NUMBER_OF_BITS-1-num_bits);
+				num_bits=0;
+			} else {
+				word1|= next_bits ((LITTLENUM_NUMBER_OF_BITS-1) - (exponent_bits+num_bits));
+				*lp++=word1;
+			}
+		}
+		while(lp<words+precision)
+			*lp++=next_bits(LITTLENUM_NUMBER_OF_BITS);
+
+		/* Round the mantissa up, but don't change the number */
+		if(next_bits(1)) {
+			--lp;
+			if(prec_bits>LITTLENUM_NUMBER_OF_BITS) {
+				int n = 0;
+				int tmp_bits;
+
+				n=0;
+				tmp_bits=prec_bits;
+				while(tmp_bits>LITTLENUM_NUMBER_OF_BITS) {
+					if(lp[n]!=(LITTLENUM_TYPE)-1)
+						break;
+					--n;
+					tmp_bits-=LITTLENUM_NUMBER_OF_BITS;
+				}
+				if(tmp_bits>LITTLENUM_NUMBER_OF_BITS || (lp[n]&mask[tmp_bits])!=mask[tmp_bits]) {
+					unsigned long carry;
+
+					for (carry = 1; carry && (lp >= words); lp --) {
+						carry = * lp + carry;
+						* lp = carry;
+						carry >>= LITTLENUM_NUMBER_OF_BITS;
+					}
+				}
+			} else if((*lp&mask[prec_bits])!=mask[prec_bits])
+				lp++;
+		}
+
+		return return_value;
+	} else 	if (exponent_4 & ~ mask [exponent_bits]) {
+			/*
+			 * Exponent overflow. Lose immediately.
+			 */
+
+			/*
+			 * We leave return_value alone: admit we read the
+			 * number, but return a floating exception
+			 * because we can't encode the number.
+			 */
+		make_invalid_floating_point_number (words);
+		return return_value;
+	} else {
+		word1 |=  (exponent_4 << ((LITTLENUM_NUMBER_OF_BITS-1) - exponent_bits))
+			| next_bits ((LITTLENUM_NUMBER_OF_BITS-1) - exponent_bits);
+	}
+
+	* lp ++ = word1;
+
+	/* X_PRECISION is special: it has 16 bits of zero in the middle,
+	   followed by a 1 bit. */
+	if(exponent_bits==15 && precision==X_PRECISION) {
+		*lp++=0;
+		*lp++= 1<<(LITTLENUM_NUMBER_OF_BITS)|next_bits(LITTLENUM_NUMBER_OF_BITS-1);
+	}
+
+	/* The rest of the words are just mantissa bits. */
+	while(lp < words + precision)
+		*lp++ = next_bits (LITTLENUM_NUMBER_OF_BITS);
+
+	if (next_bits (1)) {
+		unsigned long	carry;
+			/*
+			 * Since the NEXT bit is a 1, round UP the mantissa.
+			 * The cunning design of these hidden-1 floats permits
+			 * us to let the mantissa overflow into the exponent, and
+			 * it 'does the right thing'. However, we lose if the
+			 * highest-order bit of the lowest-order word flips.
+			 * Is that clear?
+			 */
+
+
+/* #if (sizeof(carry)) < ((sizeof(bits[0]) * BITS_PER_CHAR) + 2)
+	Please allow at least 1 more bit in carry than is in a LITTLENUM.
+	We need that extra bit to hold a carry during a LITTLENUM carry
+	propagation. Another extra bit (kept 0) will assure us that we
+	don't get a sticky sign bit after shifting right, and that
+	permits us to propagate the carry without any masking of bits.
+#endif */
+		for (carry = 1, lp --; carry && (lp >= words); lp --) {
+			carry = * lp + carry;
+			* lp = carry;
+			carry >>= LITTLENUM_NUMBER_OF_BITS;
+		}
+		if ( (word1 ^ *words) & (1 << (LITTLENUM_NUMBER_OF_BITS - 1)) ) {
+			/* We leave return_value alone: admit we read the
+			 * number, but return a floating exception
+			 * because we can't encode the number.
+			 */
+			*words&= ~ (1 << (LITTLENUM_NUMBER_OF_BITS - 1));
+			/* make_invalid_floating_point_number (words); */
+			/* return return_value; */
+		}
+	}
+	return (return_value);
+}
+
+/* This routine is a real kludge.  Someone really should do it better, but
+   I'm too lazy, and I don't understand this stuff all too well anyway
+   (JF)
+ */
+void
+int_to_gen(x)
+long x;
+{
+	char buf[20];
+	char *bufp;
+
+	sprintf(buf,"%ld",x);
+	bufp= &buf[0];
+	if(atof_generic(&bufp,".", EXP_CHARS, &generic_floating_point_number))
+		as_bad("Error converting number to floating point (Exponent overflow?)");
+}
+
+#ifdef TEST
+char *
+print_gen(gen)
+FLONUM_TYPE *gen;
+{
+	FLONUM_TYPE f;
+	LITTLENUM_TYPE arr[10];
+	double dv;
+	float fv;
+	static char sbuf[40];
+
+	if(gen) {
+		f=generic_floating_point_number;
+		generic_floating_point_number= *gen;
+	}
+	gen_to_words(&arr[0],4,11);
+	bcopy(&arr[0],&dv,sizeof(double));
+	sprintf(sbuf,"%x %x %x %x %.14G   ",arr[0],arr[1],arr[2],arr[3],dv);
+	gen_to_words(&arr[0],2,8);
+	bcopy(&arr[0],&fv,sizeof(float));
+	sprintf(sbuf+strlen(sbuf),"%x %x %.12g\n",arr[0],arr[1],fv);
+	if(gen)
+		generic_floating_point_number=f;
+	return sbuf;
+}
+#endif