[clang] [CIR] Upstream new SetBitfieldOp for handling C and C++ struct bitfields (PR #147609)

[Erich Keane via cfe-commits]

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@@ -1063,10 +1078,10 @@ LValue CIRGenFunction::emitBinaryOperatorLValue(const BinaryOperator *e) {
 
     SourceLocRAIIObject loc{*this, getLoc(e->getSourceRange())};
     if (lv.isBitField()) {
-      cgm.errorNYI(e->getSourceRange(), "bitfields");
-      return {};
+      emitStoreThroughBitfieldLValue(rv, lv);
+    } else {
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erichkeane wrote:

don't use curleys on single-line if/else.

https://github.com/llvm/llvm-project/pull/147609