[clang] [llvm] [WIP] Add support for O64 Mips ABI (PR #223990)

[Alex Rønne Petersen via cfe-commits]

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@@ -117,6 +122,19 @@ class LLVM_LIBRARY_VISIBILITY MipsTargetInfo : public TargetInfo {
     SuitableAlign = 64;
   }
 
+  void setO64ABITypes() {
+    Int64Type = SignedLongLong;
+    IntMaxType = Int64Type;
+    LongDoubleFormat = &llvm::APFloat::IEEEquad();
+    LongDoubleWidth = LongDoubleAlign = 128;
+    LongWidth = LongAlign = 64;
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alexrp wrote:

My understanding from the GCC docs is that `LongWidth` and `PointerWidth` should be 32 for `-mlong32` which is the default for O64, and `-mlong64` makes them 64.

https://github.com/llvm/llvm-project/pull/223990