make fltcalc.c more portable (and msvc independent)

diff --git a/ir/tv/fltcalc.c b/ir/tv/fltcalc.c
index b9e1e26..6db1bfe 100644 (file)
--- a/ir/tv/fltcalc.c
+++ b/ir/tv/fltcalc.c
@@ -36,19 +36,43 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <assert.h>
+#include <stdbool.h>
 
 #include "xmalloc.h"
 
-#ifdef _MSC_VER
-#include <float.h>
-#define isnan(x)   _isnan(x)
-static inline int isinf(double x)
+/*
+ * portability stuff (why do we even care about the msvc people with their C89?)
+ */
+
+
+static long double string_to_long_double(const char *str)
 {
-       return !_finite(x) && !_isnan(x);
+#if __STDC_VERSION__ >= 199901L || _POSIX_C_SOURCE >= 200112L
+       return strtold(str, NULL);
+#else
+       return strtod(str, NULL);
+#endif
 }
-#define strtold(s, e) strtod(s, e)
-#define SIZEOF_LONG_DOUBLE_8
+
+static bool my_isnan(long double val)
+{
+#if __STDC_VERSION__ >= 199901L
+       return isnan(val);
+#else
+       /* hopefully the compiler does not optimize aggressively (=incorrect) */
+       return val != val;
 #endif
+}
+
+static bool my_isinf(long double val)
+{
+#if __STDC_VERSION__ >= 199901L
+       return isinf(val);
+#else
+       /* hopefully the compiler does not optimize aggressively (=incorrect) */
+       return my_isnan(val-val) && !my_isnan(val);
+#endif
+}
 
 /** The number of extra precision rounding bits */
 #define ROUNDING_BITS 2
@@ -60,15 +84,25 @@ typedef union {
 #else
                uint32_t low;
 #endif
-#ifndef SIZEOF_LONG_DOUBLE_8
                uint32_t mid;
+#ifdef WORDS_BIGENDIAN
+               uint32_t low;
+#else
+               uint32_t high;
+#endif
+       } val_ld12;
+       struct {
+#ifdef WORDS_BIGENDIAN
+               uint32_t high;
+#else
+               uint32_t low;
 #endif
 #ifdef WORDS_BIGENDIAN
                uint32_t low;
 #else
                uint32_t high;
 #endif
-       } val;
+       } val_ld8;
        volatile long double d;
 } value_t;
 
@@ -817,7 +851,7 @@ void *fc_val_from_str(const char *str, size_t len, const ieee_descriptor_t *desc
        buffer = (char*) alloca(len+1);
        memcpy(buffer, str, len);
        buffer[len] = '\0';
-       val = strtold(buffer, NULL);
+       val = string_to_long_double(buffer);
 
        DEBUGPRINTF(("val_from_str(%s)\n", str));
        tmp_desc.exponent_size = 15;
@@ -836,25 +870,28 @@ fp_value *fc_val_from_ieee754(long double l, const ieee_descriptor_t *desc, fp_v
        value_t  srcval;
        char     sign;
        uint32_t exponent, mantissa0, mantissa1;
+       size_t   long_double_size = sizeof(long double);
 
        srcval.d = l;
        bias_res = ((1 << (desc->exponent_size - 1)) - 1);
 
-#ifdef SIZEOF_LONG_DOUBLE_8
-       mant_val  = 52;
-       bias_val  = 0x3ff;
-       sign      = (srcval.val.high & 0x80000000) != 0;
-       exponent  = (srcval.val.high & 0x7FF00000) >> 20;
-       mantissa0 = srcval.val.high & 0x000FFFFF;
-       mantissa1 = srcval.val.low;
-#else
-       mant_val  = 63;
-       bias_val  = 0x3fff;
-       sign      = (srcval.val.high & 0x00008000) != 0;
-       exponent  = (srcval.val.high & 0x00007FFF) ;
-       mantissa0 = srcval.val.mid;
-       mantissa1 = srcval.val.low;
-#endif
+       if (long_double_size == 8) {
+               mant_val  = 52;
+               bias_val  = 0x3ff;
+               sign      = (srcval.val_ld8.high & 0x80000000) != 0;
+               exponent  = (srcval.val_ld8.high & 0x7FF00000) >> 20;
+               mantissa0 = srcval.val_ld8.high & 0x000FFFFF;
+               mantissa1 = srcval.val_ld8.low;
+       } else {
+               /* we assume an x86-like 80bit representation of the value... */
+               assert(sizeof(long double)==12 || sizeof(long double)==16);
+               mant_val  = 63;
+               bias_val  = 0x3fff;
+               sign      = (srcval.val_ld12.high & 0x00008000) != 0;
+               exponent  = (srcval.val_ld12.high & 0x00007FFF) ;
+               mantissa0 = srcval.val_ld12.mid;
+               mantissa1 = srcval.val_ld12.low;
+       }
 
        if (result == NULL) result = calc_buffer;
        temp = (char*) alloca(value_size);
@@ -871,11 +908,11 @@ fp_value *fc_val_from_ieee754(long double l, const ieee_descriptor_t *desc, fp_v
 
        /* sign and flag suffice to identify NaN or inf, no exponent/mantissa
         * encoding is needed. the function can return immediately in these cases */
-       if (isnan(l)) {
+       if (my_isnan(l)) {
                result->desc.clss = FC_NAN;
                TRACEPRINTF(("val_from_float resulted in NAN\n"));
                return result;
-       } else if (isinf(l)) {
+       } else if (my_isinf(l)) {
                result->desc.clss = FC_INF;
                TRACEPRINTF(("val_from_float resulted in %sINF\n", (result->sign == 1) ? "-" : ""));
                return result;
@@ -942,17 +979,19 @@ long double fc_val_to_ieee754(const fp_value *val)
        ieee_descriptor_t desc;
        unsigned          mantissa_size;
 
-#ifdef SIZEOF_LONG_DOUBLE_8
-       desc.exponent_size = 11;
-       desc.mantissa_size = 52;
-       desc.explicit_one  = 0;
-       desc.clss          = FC_NORMAL;
-#else
-       desc.exponent_size = 15;
-       desc.mantissa_size = 63;
-       desc.explicit_one  = 1;
-       desc.clss          = FC_NORMAL;
-#endif
+       size_t            long_double_size = sizeof(long double);
+
+       if (long_double_size == 8) {
+               desc.exponent_size = 11;
+               desc.mantissa_size = 52;
+               desc.explicit_one  = 0;
+               desc.clss          = FC_NORMAL;
+       } else {
+               desc.exponent_size = 15;
+               desc.mantissa_size = 63;
+               desc.explicit_one  = 1;
+               desc.clss          = FC_NORMAL;
+       }
        mantissa_size = desc.mantissa_size + desc.explicit_one;
 
        temp = (fp_value*) alloca(calc_buffer_size);
@@ -976,18 +1015,18 @@ long double fc_val_to_ieee754(const fp_value *val)
        for (; (byte_offset<<3) < desc.mantissa_size; byte_offset++)
                mantissa0 |= sc_sub_bits(_mant(value), mantissa_size, byte_offset) << ((byte_offset - 4) << 3);
 
-#ifdef SIZEOF_LONG_DOUBLE_8
-       mantissa0 &= 0x000FFFFF;  /* get rid of garbage */
-       buildval.val.high = sign << 31;
-       buildval.val.high |= exponent << 20;
-       buildval.val.high |= mantissa0;
-       buildval.val.low = mantissa1;
-#else
-       buildval.val.high = sign << 15;
-       buildval.val.high |= exponent;
-       buildval.val.mid = mantissa0;
-       buildval.val.low = mantissa1;
-#endif
+       if (long_double_size == 8) {
+               mantissa0 &= 0x000FFFFF;  /* get rid of garbage */
+               buildval.val_ld8.high = sign << 31;
+               buildval.val_ld8.high |= exponent << 20;
+               buildval.val_ld8.high |= mantissa0;
+               buildval.val_ld8.low = mantissa1;
+       } else {
+               buildval.val_ld12.high = sign << 15;
+               buildval.val_ld12.high |= exponent;
+               buildval.val_ld12.mid = mantissa0;
+               buildval.val_ld12.low = mantissa1;
+       }
 
        TRACEPRINTF(("val_to_float: %d-%x-%x%x\n", sign, exponent, mantissa0, mantissa1));
        return buildval.d;