--- a/stage3/constant_folding.cc Sun Jun 10 21:51:16 2012 +0100
+++ b/stage3/constant_folding.cc Mon Jun 11 15:58:44 2012 +0100
@@ -118,17 +118,40 @@
#include "constant_folding.hh"
#include <limits>
-#include <math.h> /* required for pow function */
+#include <math.h> /* required for pow function, and HUGE_VAL, HUGE_VALF, HUGE_VALL */
#include <stdlib.h> /* required for malloc() */
-#if 1
-#define UINT64_MAX (std::numeric_limits< uint64_t >::max())
-#define INT64_MAX (std::numeric_limits< int64_t >::max())
-#define INT64_MIN (std::numeric_limits< int64_t >::min())
-#else
#define __STDC_LIMIT_MACROS /* required for UINT64_MAX, INT64_MAX, INT64_MIN, ... */
#include <stdint.h> /* required for UINT64_MAX, INT64_MAX, INT64_MIN, ... */
+
+
+
+#ifndef UINT64_MAX
+ #define UINT64_MAX (std::numeric_limits< uint64_t >::max())
#endif
+#ifndef INT64_MAX
+ #define INT64_MAX (std::numeric_limits< int64_t >::max())
+#endif
+#ifndef INT64_MIN
+ #define INT64_MIN (std::numeric_limits< int64_t >::min())
+#endif
+
+#if (real64_t == float)
+ #define HUGE_VAL64 HUGE_VALF
+#elif (real64_t == double)
+ #define HUGE_VAL64 HUGE_VAL
+#elif (real64_t == long_double)
+ #define HUGE_VAL64 HUGE_VALL
+#else
+ #error Could not determine which data type is being used for real64_t (defined in absyntax.hh). Aborting!
+#endif
+
+
+
+
+
+
+
#define FIRST_(symbol1, symbol2) (((symbol1)->first_order < (symbol2)->first_order) ? (symbol1) : (symbol2))
@@ -342,12 +365,18 @@
-static void CHECK_OVERFLOW_real64(symbol_c *res) {
- if (!VALID_CVALUE(real64, res))
- return;
- /* NaN => underflow, overflow, number is a higher precision format, is a complex number (IEEE standard) */
- if (isnan(GET_CVALUE(real64, res)))
- SET_OVFLOW(real64, res);
+static void CHECK_OVERFLOW_real64(symbol_c *res_ptr) {
+ if (!VALID_CVALUE(real64, res_ptr))
+ return;
+ real64_t res = GET_CVALUE(real64, res_ptr);
+ /* NaN => underflow, overflow, number is a higher precision format, is a complex number (IEEE standard) */
+ /* The IEC 61131-3 clearly states in section '2.5.1.5.2 Numerical functions':
+ * "It is an error if the result of evaluation of one of these [numerical] functions exceeds the range of values
+ * specified for the data type of the function output, or if division by zero is attempted."
+ * For this reason, any operation that has as a result a positive or negative inifinity, is also an error!
+ */
+ if ((isnan(res)) || (res == HUGE_VAL64) || (res == -HUGE_VAL64))
+ SET_OVFLOW(real64, res_ptr);
}
@@ -371,9 +400,10 @@
/* check whether the platform on which the compiler is being run implements IEC 559 floating point data types. */
symbol_c null_symbol;
if (! (std::numeric_limits<real64_t>::is_iec559) )
- STAGE3_WARNING(&null_symbol, &null_symbol, "The platform running the compiler does not implement IEC 559 floating point numbers. "
+ STAGE3_WARNING(&null_symbol, &null_symbol, "The platform running the compiler does not implement IEC 60559 floating point numbers. "
"Any error and/or warning messages related to overflow/underflow of the result of operations on REAL/LREAL literals "
- " (i.e. constant folding) may themselves be erroneous, although are most probably correct.");
+ "(i.e. constant folding) may themselves be erroneous, although are most probably correct."
+ "However, more likely is the possible existance of overflow/underflow errors that are not detected.");
}