[clang] [compiler-rt] [lldb] [llvm] Add ARMv8-M and ARMv8.1-M support for Darwin (PR #195184)

[Doug Gregor via cfe-commits]

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@@ -2839,6 +2839,24 @@ Triple MachOObjectFile::getArchTriple(uint32_t CPUType, uint32_t CPUSubType,
       if (ArchFlag)
         *ArchFlag = "armv7s";
       return Triple("armv7s-apple-darwin");
+    case MachO::CPU_SUBTYPE_ARM_V8M_BASE:
+      if (McpuDefault)
+        *McpuDefault = "cortex-m23";
+      if (ArchFlag)
+        *ArchFlag = "armv8m.base";
+      return Triple("thumbv8m-apple-darwin");
+    case MachO::CPU_SUBTYPE_ARM_V8M_MAIN:
+      if (McpuDefault)
+        *McpuDefault = "cortex-m23";
----------------
DougGregor wrote:

Both the [wikipedia page](https://en.wikipedia.org/wiki/ARM_Cortex-M#cite_note-ARMv8-M-Manual-31) and [ARM's page on the cortex-m23](https://www.arm.com/products/silicon-ip-cpu/cortex-m/cortex-m23) say it's ARMV8-M. Is there some other consideration here?

https://github.com/llvm/llvm-project/pull/195184