From fd6d53fbad9d3f48da4910ebba12d9d2a3c24bd8 Mon Sep 17 00:00:00 2001
From: Benjamin Kramer <benny.kra@googlemail.com>
Date: Sat, 4 Dec 2010 18:05:36 +0000
Subject: [PATCH] APInt: microoptimize a few methods.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120912 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/ADT/APInt.h | 15 +++++++++------
 lib/Support/APInt.cpp    |  4 ----
 2 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/include/llvm/ADT/APInt.h b/include/llvm/ADT/APInt.h
index b3cd38af15d..722c6ba8ceb 100644
--- a/include/llvm/ADT/APInt.h
+++ b/include/llvm/ADT/APInt.h
@@ -296,7 +296,7 @@ public:
   /// @returns true if this APInt is positive.
   /// @brief Determine if this APInt Value is positive.
   bool isStrictlyPositive() const {
-    return isNonNegative() && (*this) != 0;
+    return isNonNegative() && !!*this;
   }
 
   /// This checks to see if the value has all bits of the APInt are set or not.
@@ -324,15 +324,14 @@ public:
   /// value for the APInt's bit width.
   /// @brief Determine if this is the smallest unsigned value.
   bool isMinValue() const {
-    return countPopulation() == 0;
+    return !*this;
   }
 
   /// This checks to see if the value of this APInt is the minimum signed
   /// value for the APInt's bit width.
   /// @brief Determine if this is the smallest signed value.
   bool isMinSignedValue() const {
-    return BitWidth == 1 ? VAL == 1 :
-                           isNegative() && countPopulation() == 1;
+    return BitWidth == 1 ? VAL == 1 : isNegative() && isPowerOf2();
   }
 
   /// @brief Check if this APInt has an N-bits unsigned integer value.
@@ -355,7 +354,11 @@ public:
   }
 
   /// @returns true if the argument APInt value is a power of two > 0.
-  bool isPowerOf2() const;
+  bool isPowerOf2() const {
+    if (isSingleWord())
+      return isPowerOf2_64(VAL);
+    return countPopulationSlowCase() == 1;
+  }
 
   /// isSignBit - Return true if this is the value returned by getSignBit.
   bool isSignBit() const { return isMinSignedValue(); }
@@ -363,7 +366,7 @@ public:
   /// This converts the APInt to a boolean value as a test against zero.
   /// @brief Boolean conversion function.
   bool getBoolValue() const {
-    return *this != 0;
+    return !!*this;
   }
 
   /// getLimitedValue - If this value is smaller than the specified limit,
diff --git a/lib/Support/APInt.cpp b/lib/Support/APInt.cpp
index 9d8f8be1277..e7ff15cadb8 100644
--- a/lib/Support/APInt.cpp
+++ b/lib/Support/APInt.cpp
@@ -759,10 +759,6 @@ APInt APInt::getLoBits(unsigned numBits) const {
                         BitWidth - numBits);
 }
 
-bool APInt::isPowerOf2() const {
-  return (!!*this) && !(*this & (*this - APInt(BitWidth,1)));
-}
-
 unsigned APInt::countLeadingZerosSlowCase() const {
   // Treat the most significand word differently because it might have
   // meaningless bits set beyond the precision.