Change APInt comparison with uint64_t.

[chfast]

Summary

This patch changes the way APInt is compared with a value of type uint64_t.
Before the uint64_t value was truncated to the size of APInt before comparison.
Now the comparison takes into account full 64-bit precision.

[chfast]

Fixes and more unit tests.

[chfast]

Cleanup, improve names and fix UB in APIntTest.compare* unit tests.

llvm/trunk/include/llvm/ADT/APInt.h

public:
   bool ult(const APInt &RHS) const;
 
   /// \brief Unsigned less than comparison
   ///
   /// Regards both *this as an unsigned quantity and compares it with RHS for
   /// the validity of the less-than relationship.
   ///
   /// \returns true if *this < RHS when considered unsigned.
-  bool ult(uint64_t RHS) const { return ult(APInt(getBitWidth(), RHS)); }
+  bool ult(uint64_t RHS) const {
+    return getActiveBits() > 64 ? false : getZExtValue() < RHS;
+  }
 
   /// \brief Signed less than comparison
   ///
   /// Regards both *this and RHS as signed quantities and compares them for
   /// validity of the less-than relationship.
   ///
   /// \returns true if *this < RHS when both are considered signed.
   bool slt(const APInt &RHS) const;
 
   /// \brief Signed less than comparison
   ///
   /// Regards both *this as a signed quantity and compares it with RHS for
   /// the validity of the less-than relationship.
   ///
   /// \returns true if *this < RHS when considered signed.
-  bool slt(uint64_t RHS) const { return slt(APInt(getBitWidth(), RHS)); }
+  bool slt(int64_t RHS) const {
+    return getMinSignedBits() > 64 ? isNegative() : getSExtValue() < RHS;
+  }
 
   /// \brief Unsigned less or equal comparison
   ///
   /// Regards both *this and RHS as unsigned quantities and compares them for
   /// validity of the less-or-equal relationship.
   ///
   /// \returns true if *this <= RHS when both are considered unsigned.
   bool ule(const APInt &RHS) const { return ult(RHS) || eq(RHS); }
public:
   bool ugt(const APInt &RHS) const { return !ult(RHS) && !eq(RHS); }
 
   /// \brief Unsigned greater than comparison
   ///
   /// Regards both *this as an unsigned quantity and compares it with RHS for
   /// the validity of the greater-than relationship.
   ///
   /// \returns true if *this > RHS when considered unsigned.
-  bool ugt(uint64_t RHS) const { return ugt(APInt(getBitWidth(), RHS)); }
+  bool ugt(uint64_t RHS) const {
+    return getActiveBits() > 64 ? true : getZExtValue() > RHS;
+  }
 
   /// \brief Signed greather than comparison
   ///
   /// Regards both *this and RHS as signed quantities and compares them for the
   /// validity of the greater-than relationship.
   ///
   /// \returns true if *this > RHS when both are considered signed.
   bool sgt(const APInt &RHS) const { return !slt(RHS) && !eq(RHS); }
 
   /// \brief Signed greater than comparison
   ///
   /// Regards both *this as a signed quantity and compares it with RHS for
   /// the validity of the greater-than relationship.
   ///
   /// \returns true if *this > RHS when considered signed.
-  bool sgt(uint64_t RHS) const { return sgt(APInt(getBitWidth(), RHS)); }
+  bool sgt(int64_t RHS) const {
+    return getMinSignedBits() > 64 ? !isNegative() : getSExtValue() > RHS;
+  }
 
   /// \brief Unsigned greater or equal comparison
   ///
   /// Regards both *this and RHS as unsigned quantities and compares them for
   /// validity of the greater-or-equal relationship.
   ///
   /// \returns true if *this >= RHS when both are considered unsigned.
   bool uge(const APInt &RHS) const { return !ult(RHS); }
public:
   bool sge(const APInt &RHS) const { return !slt(RHS); }
 
   /// \brief Signed greater or equal comparison
   ///
   /// Regards both *this as a signed quantity and compares it with RHS for
   /// the validity of the greater-or-equal relationship.
   ///
   /// \returns true if *this >= RHS when considered signed.
-  bool sge(uint64_t RHS) const { return !slt(RHS); }
+  bool sge(int64_t RHS) const { return !slt(RHS); }
 
   /// This operation tests if there are any pairs of corresponding bits
   /// between this APInt and RHS that are both set.
   bool intersects(const APInt &RHS) const { return (*this & RHS) != 0; }
 
   /// @}
   /// \name Resizing Operators
   /// @{

llvm/trunk/unittests/ADT/APIntTest.cpp

for (auto &arg2 : testVals) {
 
       EXPECT_EQ(sv1 <  sv2, arg1.slt(sv2));
       EXPECT_EQ(sv1 <= sv2, arg1.sle(sv2));
       EXPECT_EQ(sv1 >  sv2, arg1.sgt(sv2));
       EXPECT_EQ(sv1 >= sv2, arg1.sge(sv2));
     }
 }
 
+TEST(APIntTest, compareWithRawIntegers) {
+  EXPECT_TRUE(!APInt(8, 1).uge(256));
+  EXPECT_TRUE(!APInt(8, 1).ugt(256));
+  EXPECT_TRUE( APInt(8, 1).ule(256));
+  EXPECT_TRUE( APInt(8, 1).ult(256));
+  EXPECT_TRUE(!APInt(8, 1).sge(256));
+  EXPECT_TRUE(!APInt(8, 1).sgt(256));
+  EXPECT_TRUE( APInt(8, 1).sle(256));
+  EXPECT_TRUE( APInt(8, 1).slt(256));
+  EXPECT_TRUE(!(APInt(8, 0) == 256));
+  EXPECT_TRUE(  APInt(8, 0) != 256);
+  EXPECT_TRUE(!(APInt(8, 1) == 256));
+  EXPECT_TRUE(  APInt(8, 1) != 256);
+
+  auto uint64max = UINT64_MAX;
+  auto int64max  = INT64_MAX;
+  auto int64min  = INT64_MIN;
+
+  auto u64 = APInt{128, uint64max};
+  auto s64 = APInt{128, static_cast<uint64_t>(int64max), true};
+  auto big = u64 + 1;
+
+  EXPECT_TRUE( u64.uge(uint64max));
+  EXPECT_TRUE(!u64.ugt(uint64max));
+  EXPECT_TRUE( u64.ule(uint64max));
+  EXPECT_TRUE(!u64.ult(uint64max));
+  EXPECT_TRUE( u64.sge(int64max));
+  EXPECT_TRUE( u64.sgt(int64max));
+  EXPECT_TRUE(!u64.sle(int64max));
+  EXPECT_TRUE(!u64.slt(int64max));
+  EXPECT_TRUE( u64.sge(int64min));
+  EXPECT_TRUE( u64.sgt(int64min));
+  EXPECT_TRUE(!u64.sle(int64min));
+  EXPECT_TRUE(!u64.slt(int64min));
+
+  EXPECT_TRUE(u64 == uint64max);
+  EXPECT_TRUE(u64 != int64max);
+  EXPECT_TRUE(u64 != int64min);
+
+  EXPECT_TRUE(!s64.uge(uint64max));
+  EXPECT_TRUE(!s64.ugt(uint64max));
+  EXPECT_TRUE( s64.ule(uint64max));
+  EXPECT_TRUE( s64.ult(uint64max));
+  EXPECT_TRUE( s64.sge(int64max));
+  EXPECT_TRUE(!s64.sgt(int64max));
+  EXPECT_TRUE( s64.sle(int64max));
+  EXPECT_TRUE(!s64.slt(int64max));
+  EXPECT_TRUE( s64.sge(int64min));
+  EXPECT_TRUE( s64.sgt(int64min));
+  EXPECT_TRUE(!s64.sle(int64min));
+  EXPECT_TRUE(!s64.slt(int64min));
+
+  EXPECT_TRUE(s64 != uint64max);
+  EXPECT_TRUE(s64 == int64max);
+  EXPECT_TRUE(s64 != int64min);
+
+  EXPECT_TRUE( big.uge(uint64max));
+  EXPECT_TRUE( big.ugt(uint64max));
+  EXPECT_TRUE(!big.ule(uint64max));
+  EXPECT_TRUE(!big.ult(uint64max));
+  EXPECT_TRUE( big.sge(int64max));
+  EXPECT_TRUE( big.sgt(int64max));
+  EXPECT_TRUE(!big.sle(int64max));
+  EXPECT_TRUE(!big.slt(int64max));
+  EXPECT_TRUE( big.sge(int64min));
+  EXPECT_TRUE( big.sgt(int64min));
+  EXPECT_TRUE(!big.sle(int64min));
+  EXPECT_TRUE(!big.slt(int64min));
+
+  EXPECT_TRUE(big != uint64max);
+  EXPECT_TRUE(big != int64max);
+  EXPECT_TRUE(big != int64min);
+}
+
+TEST(APIntTest, compareWithInt64Min) {
+  int64_t edge = INT64_MIN;
+  int64_t edgeP1 = edge + 1;
+  int64_t edgeM1 = INT64_MAX;
+  auto a = APInt{64, static_cast<uint64_t>(edge), true};
+
+  EXPECT_TRUE(!a.slt(edge));
+  EXPECT_TRUE( a.sle(edge));
+  EXPECT_TRUE(!a.sgt(edge));
+  EXPECT_TRUE( a.sge(edge));
+  EXPECT_TRUE( a.slt(edgeP1));
+  EXPECT_TRUE( a.sle(edgeP1));
+  EXPECT_TRUE(!a.sgt(edgeP1));
+  EXPECT_TRUE(!a.sge(edgeP1));
+  EXPECT_TRUE( a.slt(edgeM1));
+  EXPECT_TRUE( a.sle(edgeM1));
+  EXPECT_TRUE(!a.sgt(edgeM1));
+  EXPECT_TRUE(!a.sge(edgeM1));
+}
+
+TEST(APIntTest, compareWithHalfInt64Max) {
+  uint64_t edge = 0x4000000000000000;
+  uint64_t edgeP1 = edge + 1;
+  uint64_t edgeM1 = edge - 1;
+  auto a = APInt{64, edge};
+
+  EXPECT_TRUE(!a.ult(edge));
+  EXPECT_TRUE( a.ule(edge));
+  EXPECT_TRUE(!a.ugt(edge));
+  EXPECT_TRUE( a.uge(edge));
+  EXPECT_TRUE( a.ult(edgeP1));
+  EXPECT_TRUE( a.ule(edgeP1));
+  EXPECT_TRUE(!a.ugt(edgeP1));
+  EXPECT_TRUE(!a.uge(edgeP1));
+  EXPECT_TRUE(!a.ult(edgeM1));
+  EXPECT_TRUE(!a.ule(edgeM1));
+  EXPECT_TRUE( a.ugt(edgeM1));
+  EXPECT_TRUE( a.uge(edgeM1));
+
+  EXPECT_TRUE(!a.slt(edge));
+  EXPECT_TRUE( a.sle(edge));
+  EXPECT_TRUE(!a.sgt(edge));
+  EXPECT_TRUE( a.sge(edge));
+  EXPECT_TRUE( a.slt(edgeP1));
+  EXPECT_TRUE( a.sle(edgeP1));
+  EXPECT_TRUE(!a.sgt(edgeP1));
+  EXPECT_TRUE(!a.sge(edgeP1));
+  EXPECT_TRUE(!a.slt(edgeM1));
+  EXPECT_TRUE(!a.sle(edgeM1));
+  EXPECT_TRUE( a.sgt(edgeM1));
+  EXPECT_TRUE( a.sge(edgeM1));
+}
+
 
 // Tests different div/rem varaints using scheme (a * b + c) / a
 void testDiv(APInt a, APInt b, APInt c) {
   ASSERT_TRUE(a.uge(b)); // Must: a >= b
   ASSERT_TRUE(a.ugt(c)); // Must: a > c
 
   auto p = a * b + c;