[clang] [PowerPC] make `_Complex` ABI GCC-compatible (PR #208917)

[Jessica Clarke via cfe-commits]

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@@ -361,7 +361,18 @@ class PPC32_SVR4_ABIInfo : public DefaultABIInfo {
   bool IsSoftFloatABI;
   bool IsRetSmallStructInRegABI;
 
+  // Number of GPRs (r3..=r10) available for passing arguments, and their width.
+  static const int NumArgGPRs = 8;
+  static const unsigned GPRBits = 32;
+
+  bool isComplexGnuABI() const {
+    return !getTarget().getTriple().isOSDarwin() &&
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jrtc27 wrote:

Probably not, FreeBSD tends to follow Linux in these matters? But IANA PowerPC person (nor really a floating-point person). CC @chmeeedalf.

https://github.com/llvm/llvm-project/pull/208917