[clang] [clang][bytecode] Fix IntegralAP::{isMin,isMax} (PR #145339)

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llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: Timm Baeder (tbaederr)

<details>
<summary>Changes</summary>

We need to take signeness into account here.

---
Full diff: https://github.com/llvm/llvm-project/pull/145339.diff


2 Files Affected:

- (modified) clang/lib/AST/ByteCode/IntegralAP.h (+10-2) 
- (modified) clang/test/AST/ByteCode/intap.cpp (+7) 


``````````diff
diff --git a/clang/lib/AST/ByteCode/IntegralAP.h b/clang/lib/AST/ByteCode/IntegralAP.h
index e7499fc9bf5a9..6683db941c736 100644
--- a/clang/lib/AST/ByteCode/IntegralAP.h
+++ b/clang/lib/AST/ByteCode/IntegralAP.h
@@ -163,8 +163,16 @@ template <bool Signed> class IntegralAP final {
       return !getValue().isNonNegative();
     return false;
   }
-  bool isMin() const { return getValue().isMinValue(); }
-  bool isMax() const { return getValue().isMaxValue(); }
+  bool isMin() const {
+    if constexpr (Signed)
+      return getValue().isMinSignedValue();
+    return getValue().isMinValue();
+  }
+  bool isMax() const {
+    if constexpr (Signed)
+      return getValue().isMaxSignedValue();
+    return getValue().isMaxValue();
+  }
   static constexpr bool isSigned() { return Signed; }
   bool isMinusOne() const { return Signed && getValue().isAllOnes(); }
 
diff --git a/clang/test/AST/ByteCode/intap.cpp b/clang/test/AST/ByteCode/intap.cpp
index 11dd9edb61a94..a7e43b34a7d2b 100644
--- a/clang/test/AST/ByteCode/intap.cpp
+++ b/clang/test/AST/ByteCode/intap.cpp
@@ -48,6 +48,13 @@ static_assert(DivA / DivB == 2, "");
 constexpr _BitInt(4) DivC = DivA / 0; // both-error {{must be initialized by a constant expression}} \
                                       // both-note {{division by zero}}
 
+constexpr __int128 isMinDiv() {
+  return __int128{0} / __int128{-1};
+}
+static_assert(isMinDiv() == 0, "");
+
+
+
 constexpr _BitInt(7) RemA = 47;
 constexpr _BitInt(6) RemB = 9;
 static_assert(RemA % RemB == 2, "");

``````````

</details>


https://github.com/llvm/llvm-project/pull/145339