ack/h/con_float
David Given 53f7de794a Ansify.
2018-09-10 22:55:05 +02:00

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/*
(c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
See the copyright notice in the ACK home directory, in the file "Copyright".
*/
/* $Id$ */
/*
#define CODE_GENERATOR for code generator
#define CODE_EXPANDER for code expander
#define IEEEFLOAT for machines using IEEE floating point format
#define PDPFLOAT for machines using the PDP-11 floating point format
If none of these are defined, the format of the machine on which the
code generator runs is used.
Returns 1 if sz has an illegal value, 2 in case of overflow,
and 0 if all went well.
If neither IEEEFLOAT nor PDPFLOAT are defined, the return value is not
trustworthy.
Unfortunately, the IEEE standard does not define the byte-order.
depends on the #defines
FL_MSL_AT_LOW_ADDRESS 1 if most significant long is at low address
FL_MSW_AT_LOW_ADDRESS 1 if most significant word is at low address
FL_MSB_AT_LOW_ADDRESS 1 if most significant byte is at low address
*/
#ifdef IEEEFLOAT
#define USE_FLT
#endif
#ifdef PDPFLOAT
#define USE_FLT
#undef FL_MSL_AT_LOW_ADDRESS
#define FL_MSL_AT_LOW_ADDRESS 1
#undef FL_MSW_AT_LOW_ADDRESS
#define FL_MSW_AT_LOW_ADDRESS 1
#undef FL_MSB_AT_LOW_ADDRESS
#define FL_MSB_AT_LOW_ADDRESS 0
#endif
#define I0 \
((FL_MSL_AT_LOW_ADDRESS ? 0 : 4) + (FL_MSW_AT_LOW_ADDRESS ? 0 : 2) \
+ (FL_MSB_AT_LOW_ADDRESS ? 0 : 1))
#define I1 \
((FL_MSL_AT_LOW_ADDRESS ? 0 : 4) + (FL_MSW_AT_LOW_ADDRESS ? 0 : 2) \
+ (FL_MSB_AT_LOW_ADDRESS ? 1 : 0))
#define I2 \
((FL_MSL_AT_LOW_ADDRESS ? 0 : 4) + (FL_MSW_AT_LOW_ADDRESS ? 2 : 0) \
+ (FL_MSB_AT_LOW_ADDRESS ? 0 : 1))
#define I3 \
((FL_MSL_AT_LOW_ADDRESS ? 0 : 4) + (FL_MSW_AT_LOW_ADDRESS ? 2 : 0) \
+ (FL_MSB_AT_LOW_ADDRESS ? 1 : 0))
#define I4 \
((FL_MSL_AT_LOW_ADDRESS ? 4 : 0) + (FL_MSW_AT_LOW_ADDRESS ? 0 : 2) \
+ (FL_MSB_AT_LOW_ADDRESS ? 0 : 1))
#define I5 \
((FL_MSL_AT_LOW_ADDRESS ? 4 : 0) + (FL_MSW_AT_LOW_ADDRESS ? 0 : 2) \
+ (FL_MSB_AT_LOW_ADDRESS ? 1 : 0))
#define I6 \
((FL_MSL_AT_LOW_ADDRESS ? 4 : 0) + (FL_MSW_AT_LOW_ADDRESS ? 2 : 0) \
+ (FL_MSB_AT_LOW_ADDRESS ? 0 : 1))
#define I7 \
((FL_MSL_AT_LOW_ADDRESS ? 4 : 0) + (FL_MSW_AT_LOW_ADDRESS ? 2 : 0) \
+ (FL_MSB_AT_LOW_ADDRESS ? 1 : 0))
#ifndef USE_FLT
static int float_cst(str, sz, buf) char *str, *buf;
int sz;
{
int i;
char* p;
float fl;
double f;
double atof();
if (sz != 4 && sz != 8)
{
return 1;
}
f = atof(str);
if (sz == 4)
{
fl = f;
p = (char*)&fl;
}
else
{
p = (char*)&f;
}
for (i = sz; i; i--)
{
*buf++ = *p++;
}
return 0;
}
#else /* USE_FLT */
#include <ctype.h>
#include <flt_arith.h>
int float_cst(str, sz, buf) char *str, *buf;
int sz;
{
int overflow = 0;
flt_arith e;
if (sz != 4 && sz != 8)
{
return 1;
}
flt_str2flt(str, &e);
#ifdef IEEEFLOAT
if (sz == 4)
{
#endif
#ifdef PDPFLOAT
e.flt_exp += 129;
#else
e.flt_exp += 127;
#endif
if (e.flt_mantissa.flt_h_32 == 0)
e.flt_exp = 0;
#ifdef IEEEFLOAT
if (e.flt_mantissa.flt_h_32 & 0x80)
{
/* rounding */
if ((e.flt_mantissa.flt_h_32 & 0xffffff00) == 0xffffff00)
{
e.flt_exp++;
e.flt_mantissa.flt_h_32 = 0x80000000;
}
else
{
e.flt_mantissa.flt_h_32 += 0x80;
}
}
if (e.flt_exp >= 255)
{
overflow = 1;
e.flt_exp = 255;
e.flt_mantissa.flt_h_32 = e.flt_mantissa.flt_l_32 = 0;
}
if (e.flt_exp <= 0)
{
flt_b64_sft(&(e.flt_mantissa), 1);
if (e.flt_exp < 0)
{
flt_b64_sft(&(e.flt_mantissa), -e.flt_exp);
e.flt_exp = 0;
}
}
#endif
#ifndef IEEEFLOAT
if (sz == 4 && (e.flt_mantissa.flt_h_32 & 0x80))
{
/* rounding */
if ((e.flt_mantissa.flt_h_32 & 0xffffff00) == 0xffffff00)
{
e.flt_exp++;
e.flt_mantissa.flt_h_32 = 0x80000000;
}
else
{
e.flt_mantissa.flt_h_32 += 0x80;
}
}
if (sz == 8 && (e.flt_mantissa.flt_l_32 & 0x80))
{
/* rounding */
if ((e.flt_mantissa.flt_l_32 & 0xffffff00) == 0xffffff00)
{
e.flt_mantissa.flt_l_32 = 0;
if (e.flt_mantissa.flt_h_32 == 0xffffffff)
{
e.flt_exp++;
e.flt_mantissa.flt_h_32 = 0x80000000;
}
else
e.flt_mantissa.flt_h_32++;
}
else
{
e.flt_mantissa.flt_l_32 += 0x80;
}
}
if (e.flt_exp > 255)
{
overflow = 1;
e.flt_exp = 255;
e.flt_mantissa.flt_h_32 = e.flt_mantissa.flt_l_32 = 0xffffffff;
}
#endif
buf[I0] = (e.flt_sign << 7) | (e.flt_exp >> 1);
buf[I1] = ((e.flt_exp & 1) << 7) | ((e.flt_mantissa.flt_h_32 & 0x7fffffff) >> 24);
buf[I2] = e.flt_mantissa.flt_h_32 >> 16;
buf[I3] = e.flt_mantissa.flt_h_32 >> 8;
#ifndef IEEEFLOAT
if (sz == 8)
{
buf[I4] = e.flt_mantissa.flt_h_32;
buf[I5] = e.flt_mantissa.flt_l_32 >> 24;
buf[I6] = e.flt_mantissa.flt_l_32 >> 16;
buf[I7] = e.flt_mantissa.flt_l_32 >> 8;
flt_b64_sft(&(e.flt_mantissa), -56);
}
else
#endif
flt_b64_sft(&(e.flt_mantissa), -24);
#ifdef IEEEFLOAT
}
else
{
e.flt_exp += 1023;
if (e.flt_mantissa.flt_h_32 == 0)
e.flt_exp = 0;
if (e.flt_mantissa.flt_l_32 & 0x400)
{
/* rounding */
if ((e.flt_mantissa.flt_l_32 & 0xfffff800) == 0xfffff800)
{
e.flt_mantissa.flt_l_32 = 0;
if (e.flt_mantissa.flt_h_32 == 0xffffffff)
{
e.flt_exp++;
e.flt_mantissa.flt_h_32 = 0x80000000;
}
else
e.flt_mantissa.flt_h_32++;
}
else
{
e.flt_mantissa.flt_l_32 += 0x400;
}
}
if (e.flt_exp >= 2047)
{
overflow = 1;
e.flt_exp = 2047;
e.flt_mantissa.flt_h_32 = e.flt_mantissa.flt_l_32 = 0;
}
if (e.flt_exp <= 0)
{
flt_b64_sft(&(e.flt_mantissa), 1);
if (e.flt_exp < 0)
{
flt_b64_sft(&(e.flt_mantissa), -e.flt_exp);
e.flt_exp = 0;
}
}
buf[I0] = (e.flt_sign << 7) | (e.flt_exp >> 4);
buf[I1] = ((e.flt_exp & 017) << 4) | ((e.flt_mantissa.flt_h_32 >> 27) & 017);
buf[I2] = e.flt_mantissa.flt_h_32 >> 19;
buf[I3] = e.flt_mantissa.flt_h_32 >> 11;
buf[I4] = e.flt_mantissa.flt_h_32 >> 3;
buf[I5] = (e.flt_mantissa.flt_h_32 << 5) | ((e.flt_mantissa.flt_l_32 >> 27) & 037);
buf[I6] = e.flt_mantissa.flt_l_32 >> 19;
buf[I7] = e.flt_mantissa.flt_l_32 >> 11;
flt_b64_sft(&(e.flt_mantissa), -53);
}
#endif
#if !FL_MSL_AT_LOW_ADDRESS
if (sz == 4)
{
buf[I4] = buf[I0];
buf[I5] = buf[I1];
buf[I6] = buf[I2];
buf[I7] = buf[I3];
}
#endif
if (overflow)
{
return 2;
}
return 0;
}
#endif /* USE_FLT */
#ifdef CODE_GENERATOR
void con_float(void)
{
char buf[8];
int rval = float_cst(str, (int)argval, buf);
int i;
if (rval == 1)
{
fprintf(stderr, "float constant size = %d\n", (int)argval);
fatal("bad fcon size");
}
fprintf(codefile, "!float %s sz %d\n", str, (int)argval);
if (rval == 2)
{
fprintf(stderr, "Warning: overflow in floating point constant %s\n", str);
}
fprintf(codefile, ".data1 0%o", buf[0] & 0377);
for (i = 1; i < (int)argval; i++)
{
fprintf(codefile, ",0%o", buf[i] & 0377);
}
putc('\n', codefile);
}
#endif /* CODE_GENERATOR */
#ifdef CODE_EXPANDER
void con_float(const char* str, arith argval)
{
char buf[8];
int rval = float_cst(str, (int)argval, buf);
int i;
if (rval == 1)
{
argval = 8;
rval = float_cst(str, 8, buf);
}
for (i = 0; i < (int)argval; i++)
{
gen1(buf[i]);
}
}
#endif /* CODE_EXPANDER */