Index: gdb/gnulib/import/m4/exponentd.m4 |
diff --git a/gdb/gnulib/import/m4/exponentd.m4 b/gdb/gnulib/import/m4/exponentd.m4 |
new file mode 100644 |
index 0000000000000000000000000000000000000000..0ae4ccfac936a5a792c900c0ce1912715d6faf14 |
--- /dev/null |
+++ b/gdb/gnulib/import/m4/exponentd.m4 |
@@ -0,0 +1,116 @@ |
+# exponentd.m4 serial 3 |
+dnl Copyright (C) 2007-2008, 2010-2012 Free Software Foundation, Inc. |
+dnl This file is free software; the Free Software Foundation |
+dnl gives unlimited permission to copy and/or distribute it, |
+dnl with or without modifications, as long as this notice is preserved. |
+AC_DEFUN([gl_DOUBLE_EXPONENT_LOCATION], |
+[ |
+ AC_CACHE_CHECK([where to find the exponent in a 'double'], |
+ [gl_cv_cc_double_expbit0], |
+ [ |
+ AC_RUN_IFELSE( |
+ [AC_LANG_SOURCE([[ |
+#include <float.h> |
+#include <stddef.h> |
+#include <stdio.h> |
+#include <string.h> |
+#define NWORDS \ |
+ ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) |
+typedef union { double value; unsigned int word[NWORDS]; } memory_double; |
+static unsigned int ored_words[NWORDS]; |
+static unsigned int anded_words[NWORDS]; |
+static void add_to_ored_words (double x) |
+{ |
+ memory_double m; |
+ size_t i; |
+ /* Clear it first, in case sizeof (double) < sizeof (memory_double). */ |
+ memset (&m, 0, sizeof (memory_double)); |
+ m.value = x; |
+ for (i = 0; i < NWORDS; i++) |
+ { |
+ ored_words[i] |= m.word[i]; |
+ anded_words[i] &= m.word[i]; |
+ } |
+} |
+int main () |
+{ |
+ size_t j; |
+ FILE *fp = fopen ("conftest.out", "w"); |
+ if (fp == NULL) |
+ return 1; |
+ for (j = 0; j < NWORDS; j++) |
+ anded_words[j] = ~ (unsigned int) 0; |
+ add_to_ored_words (0.25); |
+ add_to_ored_words (0.5); |
+ add_to_ored_words (1.0); |
+ add_to_ored_words (2.0); |
+ add_to_ored_words (4.0); |
+ /* Remove bits that are common (e.g. if representation of the first mantissa |
+ bit is explicit). */ |
+ for (j = 0; j < NWORDS; j++) |
+ ored_words[j] &= ~anded_words[j]; |
+ /* Now find the nonzero word. */ |
+ for (j = 0; j < NWORDS; j++) |
+ if (ored_words[j] != 0) |
+ break; |
+ if (j < NWORDS) |
+ { |
+ size_t i; |
+ for (i = j + 1; i < NWORDS; i++) |
+ if (ored_words[i] != 0) |
+ { |
+ fprintf (fp, "unknown"); |
+ return (fclose (fp) != 0); |
+ } |
+ for (i = 0; ; i++) |
+ if ((ored_words[j] >> i) & 1) |
+ { |
+ fprintf (fp, "word %d bit %d", (int) j, (int) i); |
+ return (fclose (fp) != 0); |
+ } |
+ } |
+ fprintf (fp, "unknown"); |
+ return (fclose (fp) != 0); |
+} |
+ ]])], |
+ [gl_cv_cc_double_expbit0=`cat conftest.out`], |
+ [gl_cv_cc_double_expbit0="unknown"], |
+ [ |
+ dnl On ARM, there are two 'double' floating-point formats, used by |
+ dnl different sets of instructions: The older FPA instructions assume |
+ dnl that they are stored in big-endian word order, while the words |
+ dnl (like integer types) are stored in little-endian byte order. |
+ dnl The newer VFP instructions assume little-endian order |
+ dnl consistently. |
+ AC_EGREP_CPP([mixed_endianness], [ |
+#if defined arm || defined __arm || defined __arm__ |
+ mixed_endianness |
+#endif |
+ ], |
+ [gl_cv_cc_double_expbit0="unknown"], |
+ [ |
+ pushdef([AC_MSG_CHECKING],[:])dnl |
+ pushdef([AC_MSG_RESULT],[:])dnl |
+ pushdef([AC_MSG_RESULT_UNQUOTED],[:])dnl |
+ AC_C_BIGENDIAN( |
+ [gl_cv_cc_double_expbit0="word 0 bit 20"], |
+ [gl_cv_cc_double_expbit0="word 1 bit 20"], |
+ [gl_cv_cc_double_expbit0="unknown"]) |
+ popdef([AC_MSG_RESULT_UNQUOTED])dnl |
+ popdef([AC_MSG_RESULT])dnl |
+ popdef([AC_MSG_CHECKING])dnl |
+ ]) |
+ ]) |
+ rm -f conftest.out |
+ ]) |
+ case "$gl_cv_cc_double_expbit0" in |
+ word*bit*) |
+ word=`echo "$gl_cv_cc_double_expbit0" | sed -e 's/word //' -e 's/ bit.*//'` |
+ bit=`echo "$gl_cv_cc_double_expbit0" | sed -e 's/word.*bit //'` |
+ AC_DEFINE_UNQUOTED([DBL_EXPBIT0_WORD], [$word], |
+ [Define as the word index where to find the exponent of 'double'.]) |
+ AC_DEFINE_UNQUOTED([DBL_EXPBIT0_BIT], [$bit], |
+ [Define as the bit index in the word where to find bit 0 of the exponent of 'double'.]) |
+ ;; |
+ esac |
+]) |