[clang] [llvm] [PseudoProbe] Support emitting to COFF object (PR #123870)

[Fangrui Song via cfe-commits]

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@@ -12,7 +12,7 @@
 
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-target triple = "x86_64-unknown-linux-gnu"
+target triple = "x86_64-unknown--"
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MaskRay wrote:

Triples with unknown OS default to ELF, so this doesn't really test COFF. 

You'll have to invoke both `opt -mtriple=x86_64` and  `opt -mtriple=x86_64-windows` and omit datalayout/triple in IR.

https://github.com/llvm/llvm-project/pull/123870