[llvm] r359012 - [APSInt][OpenMP] Fix isNegative, etc. for unsigned types

[Joel E. Denny via llvm-commits]

Author: jdenny
Date: Tue Apr 23 10:04:15 2019
New Revision: 359012

URL: http://llvm.org/viewvc/llvm-project?rev=359012&view=rev
Log:
[APSInt][OpenMP] Fix isNegative, etc. for unsigned types

Without this patch, APSInt inherits APInt::isNegative, which merely
checks the sign bit without regard to whether the type is actually
signed.  isNonNegative and isStrictlyPositive call isNegative and so
are also affected.

This patch adjusts APSInt to override isNegative, isNonNegative, and
isStrictlyPositive with implementations that consider whether the type
is signed.

A large set of Clang OpenMP tests are affected.  Without this patch,
these tests assume that `true` is not a valid argument for clauses
like `collapse`.  Indeed, `true` fails APInt::isStrictlyPositive but
not APSInt::isStrictlyPositive.  This patch adjusts those tests to
assume `true` should be accepted.

This patch also adds tests revealing various other similar fixes due
to APSInt::isNegative calls in Clang's ExprConstant.cpp and
SemaExpr.cpp: `++` and `--` overflow in `constexpr`, evaluated object
size based on `alloc_size`, `<<` and `>>` shift count validation, and
OpenMP array section validation.

Reviewed By: lebedev.ri, ABataev, hfinkel

Differential Revision: https://reviews.llvm.org/D59712

Modified:
    llvm/trunk/include/llvm/ADT/APSInt.h
    llvm/trunk/unittests/ADT/APSIntTest.cpp

Modified: llvm/trunk/include/llvm/ADT/APSInt.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/APSInt.h?rev=359012&r1=359011&r2=359012&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ADT/APSInt.h (original)
+++ llvm/trunk/include/llvm/ADT/APSInt.h Tue Apr 23 10:04:15 2019
@@ -42,6 +42,24 @@ public:
   /// \param Str the string to be interpreted.
   explicit APSInt(StringRef Str);
 
+  /// Determine sign of this APSInt.
+  ///
+  /// \returns true if this APSInt is negative, false otherwise
+  bool isNegative() const { return isSigned() && APInt::isNegative(); }
+
+  /// Determine if this APSInt Value is non-negative (>= 0)
+  ///
+  /// \returns true if this APSInt is non-negative, false otherwise
+  bool isNonNegative() const { return !isNegative(); }
+
+  /// Determine if this APSInt Value is positive.
+  ///
+  /// This tests if the value of this APSInt is positive (> 0). Note
+  /// that 0 is not a positive value.
+  ///
+  /// \returns true if this APSInt is positive.
+  bool isStrictlyPositive() const { return isNonNegative() && !isNullValue(); }
+
   APSInt &operator=(APInt RHS) {
     // Retain our current sign.
     APInt::operator=(std::move(RHS));

Modified: llvm/trunk/unittests/ADT/APSIntTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/ADT/APSIntTest.cpp?rev=359012&r1=359011&r2=359012&view=diff
==============================================================================
--- llvm/trunk/unittests/ADT/APSIntTest.cpp (original)
+++ llvm/trunk/unittests/ADT/APSIntTest.cpp Tue Apr 23 10:04:15 2019
@@ -159,4 +159,90 @@ TEST(APSIntTest, StringDeath) {
 
 #endif
 
+TEST(APSIntTest, SignedHighBit) {
+  APSInt False(APInt(1, 0), false);
+  APSInt True(APInt(1, 1), false);
+  APSInt CharMin(APInt(8, 0), false);
+  APSInt CharSmall(APInt(8, 0x13), false);
+  APSInt CharBoundaryUnder(APInt(8, 0x7f), false);
+  APSInt CharBoundaryOver(APInt(8, 0x80), false);
+  APSInt CharLarge(APInt(8, 0xd9), false);
+  APSInt CharMax(APInt(8, 0xff), false);
+
+  EXPECT_FALSE(False.isNegative());
+  EXPECT_TRUE(False.isNonNegative());
+  EXPECT_FALSE(False.isStrictlyPositive());
+
+  EXPECT_TRUE(True.isNegative());
+  EXPECT_FALSE(True.isNonNegative());
+  EXPECT_FALSE(True.isStrictlyPositive());
+
+  EXPECT_FALSE(CharMin.isNegative());
+  EXPECT_TRUE(CharMin.isNonNegative());
+  EXPECT_FALSE(CharMin.isStrictlyPositive());
+
+  EXPECT_FALSE(CharSmall.isNegative());
+  EXPECT_TRUE(CharSmall.isNonNegative());
+  EXPECT_TRUE(CharSmall.isStrictlyPositive());
+
+  EXPECT_FALSE(CharBoundaryUnder.isNegative());
+  EXPECT_TRUE(CharBoundaryUnder.isNonNegative());
+  EXPECT_TRUE(CharBoundaryUnder.isStrictlyPositive());
+
+  EXPECT_TRUE(CharBoundaryOver.isNegative());
+  EXPECT_FALSE(CharBoundaryOver.isNonNegative());
+  EXPECT_FALSE(CharBoundaryOver.isStrictlyPositive());
+
+  EXPECT_TRUE(CharLarge.isNegative());
+  EXPECT_FALSE(CharLarge.isNonNegative());
+  EXPECT_FALSE(CharLarge.isStrictlyPositive());
+
+  EXPECT_TRUE(CharMax.isNegative());
+  EXPECT_FALSE(CharMax.isNonNegative());
+  EXPECT_FALSE(CharMax.isStrictlyPositive());
+}
+
+TEST(APSIntTest, UnsignedHighBit) {
+  APSInt False(APInt(1, 0));
+  APSInt True(APInt(1, 1));
+  APSInt CharMin(APInt(8, 0));
+  APSInt CharSmall(APInt(8, 0x13));
+  APSInt CharBoundaryUnder(APInt(8, 0x7f));
+  APSInt CharBoundaryOver(APInt(8, 0x80));
+  APSInt CharLarge(APInt(8, 0xd9));
+  APSInt CharMax(APInt(8, 0xff));
+
+  EXPECT_FALSE(False.isNegative());
+  EXPECT_TRUE(False.isNonNegative());
+  EXPECT_FALSE(False.isStrictlyPositive());
+
+  EXPECT_FALSE(True.isNegative());
+  EXPECT_TRUE(True.isNonNegative());
+  EXPECT_TRUE(True.isStrictlyPositive());
+
+  EXPECT_FALSE(CharMin.isNegative());
+  EXPECT_TRUE(CharMin.isNonNegative());
+  EXPECT_FALSE(CharMin.isStrictlyPositive());
+
+  EXPECT_FALSE(CharSmall.isNegative());
+  EXPECT_TRUE(CharSmall.isNonNegative());
+  EXPECT_TRUE(CharSmall.isStrictlyPositive());
+
+  EXPECT_FALSE(CharBoundaryUnder.isNegative());
+  EXPECT_TRUE(CharBoundaryUnder.isNonNegative());
+  EXPECT_TRUE(CharBoundaryUnder.isStrictlyPositive());
+
+  EXPECT_FALSE(CharBoundaryOver.isNegative());
+  EXPECT_TRUE(CharBoundaryOver.isNonNegative());
+  EXPECT_TRUE(CharBoundaryOver.isStrictlyPositive());
+
+  EXPECT_FALSE(CharLarge.isNegative());
+  EXPECT_TRUE(CharLarge.isNonNegative());
+  EXPECT_TRUE(CharLarge.isStrictlyPositive());
+
+  EXPECT_FALSE(CharMax.isNegative());
+  EXPECT_TRUE(CharMax.isNonNegative());
+  EXPECT_TRUE(CharMax.isStrictlyPositive());
+}
+
 } // end anonymous namespace