[clang] [clang][PowerPC] Add flag to enable compatibility with GNU for complex arguments (PR #77732)

[zhijian lin via cfe-commits]

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@@ -330,8 +330,12 @@ namespace {
 class PPC32_SVR4_ABIInfo : public DefaultABIInfo {
   bool IsSoftFloatABI;
   bool IsRetSmallStructInRegABI;
+  // Size of GPR in bits.
+  static const unsigned RegLen = 32;
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diggerlin wrote:

suggest change RegLen to GPRBits  as 

https://github.com/llvm/llvm-project/blob/main/clang/lib/CodeGen/Targets/PPC.cpp#L615 

https://github.com/llvm/llvm-project/pull/77732