[llvm] [RISCV] Add basic Mach-O triple support. (PR #141682)

[Sam Elliott via llvm-commits]

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@@ -275,6 +275,13 @@ static std::string computeAMDDataLayout(const Triple &TT) {
 }
 
 static std::string computeRISCVDataLayout(const Triple &TT, StringRef ABIName) {
+  if (TT.isOSBinFormatMachO()) {
+    assert(TT.isLittleEndian() && "Invalid endianness");
+    assert(TT.isArch32Bit() && "Invalid triple");
+    assert((ABIName != "ilp32e") && "Invalid ABI.");
+    return "e-m:o-p:32:32-i64:64-n32-S128";
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lenary wrote:

This asserts that the ABI is not `ilp32e`, as I understood it. 

https://github.com/llvm/llvm-project/pull/141682