Add isInteger() to APFloat.

Useful utility function; this wasn't too hard to do before, but also wasn't
obviously discoverable.  Make it explicit.  Reviewed offline by Michael
Gottesman.

llvm-svn: 253254

1 files changed, 9 insertions, 0 deletions

diff --git a/llvm/lib/Support/APFloat.cpp b/llvm/lib/Support/APFloat.cpp
index 91b3db59d0e..19b8221b60c 100644
--- a/llvm/lib/Support/APFloat.cpp
+++ b/llvm/lib/Support/APFloat.cpp
@@ -768,6 +768,15 @@ APFloat::isLargest() const {
 }
 
 bool
+APFloat::isInteger() const {
+  // This could be made more efficient; I'm going for obviously correct.
+  if (!isFinite()) return false;
+  APFloat truncated = *this;
+  truncated.roundToIntegral(rmTowardZero);
+  return compare(truncated) == cmpEqual;
+}
+
+bool
 APFloat::bitwiseIsEqual(const APFloat &rhs) const {
   if (this == &rhs)
     return true;