From 5ce3fd5f43d20c0d2178700046fcc531b0b02536 Mon Sep 17 00:00:00 2001
From: Andi Drebes <andi.drebes@zama.ai>
Date: Mon, 27 Sep 2021 16:23:14 +0200
Subject: [PATCH] refactor(compiler): Move ceilLog2 to separate header file

---
 compiler/include/zamalang/Support/math.h     | 20 ++++++++++++++++++++
 compiler/lib/Dialect/HLFHE/Analysis/MANP.cpp | 17 +----------------
 2 files changed, 21 insertions(+), 16 deletions(-)
 create mode 100644 compiler/include/zamalang/Support/math.h

diff --git a/compiler/include/zamalang/Support/math.h b/compiler/include/zamalang/Support/math.h
new file mode 100644
index 000000000..4d4de1e89
--- /dev/null
+++ b/compiler/include/zamalang/Support/math.h
@@ -0,0 +1,20 @@
+#ifndef ZAMALANG_SUPPORT_MATH_H_
+#define ZAMALANG_SUPPORT_MATH_H_
+
+// Calculates (T)ceil(log2f(v))
+// TODO: Replace with some fancy bit twiddling hack
+template <typename T> static T ceilLog2(const T v) {
+  T tmp = v;
+  T log2 = 0;
+
+  while (tmp >>= 1)
+    log2++;
+
+  // If more than MSB set, round to next highest power of 2
+  if (v & ~((T)1 << log2))
+    log2 += 1;
+
+  return log2;
+}
+
+#endif
diff --git a/compiler/lib/Dialect/HLFHE/Analysis/MANP.cpp b/compiler/lib/Dialect/HLFHE/Analysis/MANP.cpp
index 4eac5be2e..0a677cb43 100644
--- a/compiler/lib/Dialect/HLFHE/Analysis/MANP.cpp
+++ b/compiler/lib/Dialect/HLFHE/Analysis/MANP.cpp
@@ -3,6 +3,7 @@
 #include <zamalang/Dialect/HLFHE/IR/HLFHEDialect.h>
 #include <zamalang/Dialect/HLFHE/IR/HLFHEOps.h>
 #include <zamalang/Dialect/HLFHE/IR/HLFHETypes.h>
+#include <zamalang/Support/math.h>
 
 #include <limits>
 #include <llvm/ADT/APInt.h>
@@ -183,22 +184,6 @@ static llvm::APInt denseCstTensorNorm2Sq(mlir::ConstantOp cstOp) {
   return accu;
 }
 
-// Calculates (T)ceil(log2f(v))
-// TODO: Replace with some fancy bit twiddling hack
-template <typename T> static T ceilLog2(const T v) {
-  T tmp = v;
-  T log2 = 0;
-
-  while (tmp >>= 1)
-    log2++;
-
-  // If more than MSB set, round to next highest power of 2
-  if (v & ~((T)1 << log2))
-    log2 += 1;
-
-  return log2;
-}
-
 // Calculates the square of the 2-norm of a 1D tensor of signless
 // integers by conservatively assuming that the dynamic values are the
 // maximum for the integer width. Aborts if the tensor type `tTy` is