[clang] [CIR] Add x86_64 scalar calling-convention lowering (PR #209636)

[via cfe-commits]

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@@ -55,6 +60,156 @@ namespace mlir {
 
 namespace {
 
+//===----------------------------------------------------------------------===//
+// x86_64 System V classifier bridge (scalar types)
+//
+// Maps scalar CIR types to llvm::abi::Type, runs the LLVM ABI Lowering
+// Library's SysV x86_64 classifier, and converts the result back into the
+// dialect-agnostic mlir::abi::FunctionClassification that CIRABIRewriteContext
+// consumes.  Only integer / pointer / bool / f32 / f64 signatures are handled;
+// aggregates and other leaf types are reported NYI by classifyX86_64 so an
+// unsupported signature fails the pass instead of being misclassified.
+//===----------------------------------------------------------------------===//
+
+/// llvm::Align requires a power of two; DataLayout can report non-power-of-two
+/// alignments for unusual types.
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adams381 wrote:

Done -- #210187 is in, so I dropped `safeAlign` here.


https://github.com/llvm/llvm-project/pull/209636