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

[zhijian lin via cfe-commits]

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@@ -337,12 +347,58 @@ CharUnits PPC32_SVR4_ABIInfo::getParamTypeAlignment(QualType Ty) const {
   return CharUnits::fromQuantity(4);
 }
 
+ABIArgInfo PPC32_SVR4_ABIInfo::handleComplex(uint64_t &TypeSize) const {
+  llvm::Type *ElemTy;
+  unsigned RegsNeeded; // Registers Needed for Complex.
+
+  if (TypeSize == 64) {
+    ElemTy = llvm::Type::getInt64Ty(getVMContext());
+    RegsNeeded = 1;
+  } else {
+    ElemTy = llvm::Type::getInt32Ty(getVMContext());
+    RegsNeeded = (TypeSize + 31) / 32;
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diggerlin wrote:

do we need to add `+31` here , can we change to 
`RegsNeeded = TypeSize >> 5;  ` ? and 

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