[llvm] [FunctionAttrs] Bail if initializes range overflows 64-bit signed int (PR #137053)

[Arthur Eubanks via llvm-commits]

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@@ -661,8 +661,12 @@ ArgumentAccessInfo getArgumentAccessInfo(const Instruction *I,
     auto TypeSize = DL.getTypeStoreSize(Ty);
     if (!TypeSize.isScalable() && Offset) {
       int64_t Size = TypeSize.getFixedValue();
-      return ConstantRange(APInt(64, *Offset, true),
-                           APInt(64, *Offset + Size, true));
+      APInt Low(64, *Offset, true);
+      APInt High(64, *Offset + Size, true);
+      // Bail if the range overflows signed 64-bit int.
+      if (Low.sge(High))
+        return std::nullopt;
+      return ConstantRange(Low, High);
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aeubanks wrote:

I didn't see this, thanks for pointing it out. Although I ended up just using `APInt::sadd_ov`

https://github.com/llvm/llvm-project/pull/137053