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-rw-r--r--lib/powidf2.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/lib/powidf2.c b/lib/powidf2.c
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+++ b/lib/powidf2.c
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+//===-- powidf2.cpp - Implement __powidf2 ---------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __powidf2 for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "int_lib.h"
+
+// Returns: a ^ b
+
+double
+__powidf2(double a, si_int b)
+{
+ const int recip = b < 0;
+ double r = 1;
+ while (1)
+ {
+ if (b & 1)
+ r *= a;
+ b /= 2;
+ if (b == 0)
+ break;
+ a *= a;
+ }
+ return recip ? 1/r : r;
+}