[lld] [LLD][COFF] Use archive's ECSYMBOLS on ARM64EC target when available. (PR #106904)

[Jacek Caban via llvm-commits]

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+REQUIRES: aarch64, x86
+RUN: split-file %s %t.dir && cd %t.dir
+
+RUN: llvm-mc -filetype=obj -triple=arm64ec-windows symref.s -o symref-arm64ec.obj
+RUN: llvm-mc -filetype=obj -triple=arm64ec-windows nsymref.s -o nsymref-arm64ec.obj
+RUN: llvm-mc -filetype=obj -triple=aarch64-windows nsymref.s -o nsymref-aarch64.obj
+RUN: llvm-mc -filetype=obj -triple=arm64ec-windows sym.s -o sym-arm64ec.obj
+RUN: llvm-mc -filetype=obj -triple=x86_64-windows sym.s -o sym-x86_64.obj
+RUN: llvm-mc -filetype=obj -triple=aarch64-windows nsym.s -o sym-aarch64.obj
+RUN: llvm-mc -filetype=obj -triple=arm64ec-windows %S/Inputs/loadconfig-arm64ec.s -o loadconfig-arm64ec.obj
+
+RUN: llvm-lib -machine:arm64ec -out:sym-arm64ec.lib sym-arm64ec.obj sym-aarch64.obj
+RUN: llvm-lib -machine:amd64 -out:sym-x86_64.lib sym-x86_64.obj
+
+RUN: lld-link -machine:arm64ec -dll -noentry -out:test.dll symref-arm64ec.obj sym-arm64ec.lib loadconfig-arm64ec.obj
+RUN: lld-link -machine:arm64ec -dll -noentry -out:test2.dll symref-arm64ec.obj sym-x86_64.lib loadconfig-arm64ec.obj
+RUN: lld-link -machine:arm64x -dll -noentry -out:test3.dll symref-arm64ec.obj nsymref-aarch64.obj sym-arm64ec.lib loadconfig-arm64ec.obj
+
+RUN: not lld-link -machine:arm64ec -dll -noentry -out:test-err.dll nsymref-arm64ec.obj sym-arm64ec.lib loadconfig-arm64ec.obj 2>&1 |\
+RUN:              FileCheck --check-prefix=ERR %s
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cjacek wrote:

Regular map in that test has `nsym` symbol, while EC map has `sym` symbol. The test is meant to make sure that we don't resolve the symbol using wrong symbol map. Prior to this PR (or if I messed up ARM64X condition to return early), we'd try to use the regular map in this case and fail with an error that pulled object file is not compatible. It's not a very interesting test, but it seems better than nothing...

I added more comments in tests, thanks.

https://github.com/llvm/llvm-project/pull/106904