[clang] [llvm] [ARM] Add support for Windows SEH (PR #184953)

[Martin Storsjö via cfe-commits]

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@@ -1664,7 +1664,8 @@ class TargetInfo : public TransferrableTargetInfo,
   bool isSEHTrySupported() const {
     return getTriple().isOSWindows() &&
            (getTriple().isX86() ||
-            getTriple().getArch() == llvm::Triple::aarch64);
+            getTriple().getArch() == llvm::Triple::aarch64 ||
+            getTriple().isThumb());
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mstorsjo wrote:

On the external level, if you invoke `clang -target armv7-windows`, it internally switches to `thumbv7-windows`, for the reasons above. So internally it only uses thumb triples, and it may be enough to only check for thumb, not arm, but it also wouldn't hurt to check for both, for clarity.

https://github.com/llvm/llvm-project/pull/184953