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-rw-r--r--third_party/heimdal/lib/hcrypto/libtommath/bn_mp_set_double.c47
1 files changed, 47 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_set_double.c b/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_set_double.c
new file mode 100644
index 0000000..6f91b64
--- /dev/null
+++ b/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_set_double.c
@@ -0,0 +1,47 @@
+#include "tommath_private.h"
+#ifdef BN_MP_SET_DOUBLE_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
+
+#if defined(__STDC_IEC_559__) || defined(__GCC_IEC_559) || defined(__x86_64__) || defined(_M_X64) || defined(_M_AMD64) || defined(__i386__) || defined(_M_X86) || defined(__aarch64__) || defined(__arm__)
+mp_err mp_set_double(mp_int *a, double b)
+{
+ uint64_t frac;
+ int exp;
+ mp_err err;
+ union {
+ double dbl;
+ uint64_t bits;
+ } cast;
+ cast.dbl = b;
+
+ exp = (int)((unsigned)(cast.bits >> 52) & 0x7FFu);
+ frac = (cast.bits & ((1uLL << 52) - 1uLL)) | (1uLL << 52);
+
+ if (exp == 0x7FF) { /* +-inf, NaN */
+ return MP_VAL;
+ }
+ exp -= 1023 + 52;
+
+ mp_set_u64(a, frac);
+
+ err = (exp < 0) ? mp_div_2d(a, -exp, a, NULL) : mp_mul_2d(a, exp, a);
+ if (err != MP_OKAY) {
+ return err;
+ }
+
+ if (((cast.bits >> 63) != 0uLL) && !MP_IS_ZERO(a)) {
+ a->sign = MP_NEG;
+ }
+
+ return MP_OKAY;
+}
+#else
+/* pragma message() not supported by several compilers (in mostly older but still used versions) */
+# ifdef _MSC_VER
+# pragma message("mp_set_double implementation is only available on platforms with IEEE754 floating point format")
+# else
+# warning "mp_set_double implementation is only available on platforms with IEEE754 floating point format"
+# endif
+#endif
+#endif