[llvm] opt: Try to respect target-abi command line option (PR #169604)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,8 @@
+;; Check that we infer the correct datalayout from a target triple
+; RUN: opt -mtriple=mips64-- -S -passes=no-op-module -target-abi=n32 < %s | FileCheck -check-prefix=N32 %s
+; RUN: opt -mtriple=mips64-- -S -passes=no-op-module -target-abi=n64 < %s | FileCheck -check-prefix=N64 %s
+
+target datalayout = ""
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arsenm wrote:

The other tests have this. Plus I thought treating empty string as the unknown was a bit iffy since there is a default 

https://github.com/llvm/llvm-project/pull/169604