r346699 - PR39628 Treat all non-zero values as 'true' in bool compound-assignment

[Richard Smith via cfe-commits]

Author: rsmith
Date: Mon Nov 12 12:11:57 2018
New Revision: 346699

URL: http://llvm.org/viewvc/llvm-project?rev=346699&view=rev
Log:
PR39628 Treat all non-zero values as 'true' in bool compound-assignment
in constant evaluation, not just odd values.

Modified:
    cfe/trunk/lib/AST/ExprConstant.cpp
    cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp

Modified: cfe/trunk/lib/AST/ExprConstant.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ExprConstant.cpp?rev=346699&r1=346698&r2=346699&view=diff
==============================================================================
--- cfe/trunk/lib/AST/ExprConstant.cpp (original)
+++ cfe/trunk/lib/AST/ExprConstant.cpp Mon Nov 12 12:11:57 2018
@@ -2074,11 +2074,12 @@ static APSInt HandleIntToIntCast(EvalInf
                                  QualType DestType, QualType SrcType,
                                  const APSInt &Value) {
   unsigned DestWidth = Info.Ctx.getIntWidth(DestType);
-  APSInt Result = Value;
   // Figure out if this is a truncate, extend or noop cast.
   // If the input is signed, do a sign extend, noop, or truncate.
-  Result = Result.extOrTrunc(DestWidth);
+  APSInt Result = Value.extOrTrunc(DestWidth);
   Result.setIsUnsigned(DestType->isUnsignedIntegerOrEnumerationType());
+  if (DestType->isBooleanType())
+    Result = Value.getBoolValue();
   return Result;
 }
 

Modified: cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp?rev=346699&r1=346698&r2=346699&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp (original)
+++ cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp Mon Nov 12 12:11:57 2018
@@ -374,6 +374,30 @@ namespace compound_assign {
   }
   static_assert(test_float(), "");
 
+  constexpr bool test_bool() {
+    bool b = false;
+    b |= 2;
+    if (b != true) return false;
+    b <<= 1;
+    if (b != true) return false;
+    b *= 2;
+    if (b != true) return false;
+    b -= 1;
+    if (b != false) return false;
+    b -= 1;
+    if (b != true) return false;
+    b += -1;
+    if (b != false) return false;
+    b += 1;
+    if (b != true) return false;
+    b += 1;
+    if (b != true) return false;
+    b ^= b;
+    if (b != false) return false;
+    return true;
+  }
+  static_assert(test_bool(), "");
+
   constexpr bool test_ptr() {
     int arr[123] = {};
     int *p = arr;
@@ -879,7 +903,7 @@ namespace Bitfields {
     --a.n;
     --a.u;
     a.n = -a.n * 3;
-    return a.b == false && a.n == 3 && a.u == 31;
+    return a.b == true && a.n == 3 && a.u == 31;
   }
   static_assert(test(), "");
 }