[clang] [clang] Lower _BitInt(129+) to a different type in LLVM IR (PR #91364)

[Mariya Podchishchaeva via cfe-commits]

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@@ -128,6 +128,15 @@ class CodeGenTypes {
   /// memory representation is usually i8 or i32, depending on the target.
   llvm::Type *ConvertTypeForMem(QualType T, bool ForBitField = false);
 
+  /// Check that size and abi alignment of given LLVM type matches size and
+  /// alignment of given AST type.
+  bool LLVMTypeLayoutMatchesAST(QualType ASTTy, llvm::Type *LLVMTy);
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Fznamznon wrote:

`ConstantEmitter::emitForMemory` is calling `LLVMTypeLayoutMatchesAST ` to determine if a big _BitInt constant needs to be split into individual bytes.

https://github.com/llvm/llvm-project/pull/91364