[clang] [CIR] Call code gen; create empty cir.func op (PR #113483)

[Erich Keane via cfe-commits]

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@@ -24,9 +27,140 @@ CIRGenModule::CIRGenModule(mlir::MLIRContext &context,
                            clang::ASTContext &astctx,
                            const clang::CodeGenOptions &cgo,
                            DiagnosticsEngine &diags)
-    : astCtx(astctx), langOpts(astctx.getLangOpts()),
-      theModule{mlir::ModuleOp::create(mlir::UnknownLoc())},
-      target(astCtx.getTargetInfo()) {}
+    : builder(&context), astCtx(astctx), langOpts(astctx.getLangOpts()),
+      theModule{mlir::ModuleOp::create(mlir::UnknownLoc::get(&context))},
+      diags(diags), target(astCtx.getTargetInfo()) {}
+
+mlir::Location CIRGenModule::getLoc(SourceLocation cLoc) {
+  assert(cLoc.isValid() && "expected valid source location");
+  const SourceManager &sm = astCtx.getSourceManager();
+  PresumedLoc pLoc = sm.getPresumedLoc(cLoc);
+  StringRef filename = pLoc.getFilename();
+  return mlir::FileLineColLoc::get(builder.getStringAttr(filename),
+                                   pLoc.getLine(), pLoc.getColumn());
+}
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erichkeane wrote:

Do we care about macros/etc here?  `getLine` and `getColumn` I think end up being the location itself, but there is a lot of work you can do to un-fold macros.

https://github.com/llvm/llvm-project/pull/113483