[clang] [CIR] Accept fixed-width vectors in x86_64 callconv lowering (PR #215118)

[Adam Smith via cfe-commits]

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@@ -632,16 +702,33 @@ void CallConvLoweringPass::runOnOperation() {
   CIRABIRewriteContext rewriteCtx(moduleOp, dl);
   SymbolTable symbolTable(moduleOp);
 
-  // For the x86_64 target, build the LLVM ABI library classifier once and
-  // reuse it (and its type mapper) across every function.
+  // A per-function target attribute can raise the AVX level, so one classifier
+  // per module would misclassify a wide vector in such a function.
+  static constexpr unsigned numAvxLevels =
+      static_cast<unsigned>(llvm::abi::X86AVXABILevel::AVX512) + 1;
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adams381 wrote:

Opened the followup PR as #216339.

https://github.com/llvm/llvm-project/pull/215118