[clang] [clang][TableGen] Fix Duplicate Entries in TableGen (PR #140828)

[via cfe-commits]

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@@ -3727,12 +3734,26 @@ static void GenerateHasAttrSpellingStringSwitch(
       }
     }
 
-    std::string TestStr = !Test.empty()
-                              ? Test + " ? " + itostr(Version) + " : 0"
-                              : itostr(Version);
-    if (Scope.empty() || Scope == Spelling.nameSpace())
-      OS << "    .Case(\"" << Spelling.name() << "\", " << TestStr << ")\n";
+    std::string TestStr =
----------------
Mr-Anyone wrote:

Take the `interrupt` attribute as an example:

This is the original string: `true && (T.getArch() == llvm::Triple::riscv32 || T.getArch() == llvm::Triple::riscv64) ? 1 : 0`. 

The problem is that there are multiple of them for a single attribute, such as `true && (T.getArch() == llvm::Triple::arm || T.getArch() == llvm::Triple::thumb || T.getArch() == llvm::Triple::armeb || T.getArch() == llvm::Triple::thumbeb) ? 1 : 0
` for arm.

Meaning that, we used to get: 
```
.Case("interrupt",true && (T.getArch() == llvm::Triple::riscv32 || T.getArch() == llvm::Triple::riscv64) ? 1 : 0 )
.Case("interrupt",true && (T.getArch() == llvm::Triple::arm || T.getArch() == llvm::Triple::thumb || T.getArch() == llvm::Triple::armeb || T.getArch() == llvm::Triple::thumbeb) ? 1 : 0
...
```


This is the new one `TestStr`: `(true && (T.getArch() == llvm::Triple::avr) ? 1 : 0)`, with the only difference being the added parentheses. We can join test strings together with `||`, meaning we generate something like this: 


```
(true && (T.getArch() == llvm::Triple::riscv32 || T.getArch() == llvm::Triple::riscv64) ? 1 : 0) ||
                                (true && (T.getArch() == llvm::Triple::arm || T.getArch() == llvm::Triple::thumb || T.getArch() == llvm::Triple::armeb || T.getArch() == llvm::Triple::thumbeb) ? 1 : 0) ... 
```

So now we have a single case statement instead, 

```
.Case("interrupt",(true && (T.getArch() == llvm::Triple::riscv32 || T.getArch() == llvm::Triple::riscv64) ? 1 : 0) ||
                                (true && (T.getArch() == llvm::Triple::arm || T.getArch() == llvm::Triple::thumb || T.getArch() == llvm::Triple::armeb || T.getArch() == llvm::Triple::thumbeb) ? 1 : 0) ... )
...
```


https://github.com/llvm/llvm-project/pull/140828