[lld] [lld][AArch64] Add support for GCS (PR #90732)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,66 @@
+# REQUIRES: aarch64
+# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-gnu %s -o %t1.o
+# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-gnu %p/Inputs/aarch64-func2-gcs.s -o %t2.o
+# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-gnu %p/Inputs/aarch64-func3-gcs.s -o %t3.o
+# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-gnu %p/Inputs/aarch64-func2.s -o %t2no.o
+# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-gnu %p/Inputs/aarch64-func3.s -o %t3no.o
+
+# GCS should be enabled when it's enabled in all inputs or when it's forced on.
+
+# RUN: ld.lld %t1.o %t2.o %t3.o --shared -o %t.exe
+# RUN: llvm-readelf -n %t.exe | FileCheck --check-prefix GCS %s
+# RUN: ld.lld %t1.o %t3.o --shared -o %t.so
+# RUN: llvm-readelf -n %t.so | FileCheck --check-prefix GCS %s
+# RUN: ld.lld %t1.o %t2no.o %t3.o --shared -o %tforce.exe -z gcs
+# RUN: llvm-readelf -n %tforce.exe | FileCheck --allow-empty --check-prefix GCS %s
+# RUN: ld.lld %t2.o %t3no.o --shared -o %tforce.so -z gcs=always
+# RUN: llvm-readelf -n %tforce.so | FileCheck --allow-empty --check-prefix GCS %s
+# RUN: ld.lld %t2.o %t3no.o --shared -o %tforce2.so -z gcs=never -z gcs=always
+# RUN: llvm-readelf -n %tforce2.so | FileCheck --allow-empty --check-prefix GCS %s
+
+# GCS: Properties:    aarch64 feature: GCS
+
+# GCS should not be enabled if it's not enabled in at least one input, and we
+# should warn or error when using the report option.
+
+# RUN: ld.lld %t1.o %t2no.o %t3.o --shared -o %tno.exe
+# RUN: llvm-readelf -n %tno.exe | FileCheck --allow-empty --check-prefix NOGCS %s
+# RUN: ld.lld %t2.o %t3no.o --shared -o %tno.so
+# RUN: llvm-readelf -n %tno.so | FileCheck --allow-empty --check-prefix NOGCS %s
+# RUN: ld.lld %t1.o %t2no.o %t3.o --shared -o %tno.exe -z gcs-report=warning 2>&1 | FileCheck --check-prefix=REPORT-WARN %s
+# RUN: llvm-readelf -n %tno.exe | FileCheck --allow-empty --check-prefix NOGCS %s
+# RUN: not ld.lld %t2.o %t3no.o --shared -o %tno.so -z gcs-report=error 2>&1 | FileCheck --check-prefix=REPORT-ERROR %s
+
+# NOGCS-NOT: Properties
+# REPORT-WARN: warning: {{.*}}tmp2no.o: -z gcs-report: file does not have GNU_PROPERTY_AARCH64_FEATURE_1_GCS property
+# REPORT-ERROR: error: {{.*}}tmp3no.o: -z gcs-report: file does not have GNU_PROPERTY_AARCH64_FEATURE_1_GCS property
+
+# GCS should be disabled with gcs=never, even if GCS is present in all inputs.
+
+# RUN: ld.lld %t1.o %t2.o %t3.o -z gcs=never --shared -o %tnever.exe
+# RUN: llvm-readelf -n %tnever.exe | FileCheck --allow-empty --check-prefix NOGCS %s
+# RUN: ld.lld %t1.o %t2.o %t3.o -z gcs=always -z gcs=never --shared -o %tnever2.exe
+# RUN: llvm-readelf -n %tnever2.exe | FileCheck --allow-empty --check-prefix NOGCS %s
+
+# An invalid gcs option should give an error
+# RUN: not ld.lld %t1.o %t2.o %t3.o -z gcs=nonsense -o %tinvalid.exe 2>&1 | FileCheck --check-prefix=INVALID %s
----------------
MaskRay wrote:

If `# RUN: rm -rf %t && split-file %s %t && cd %t` is used, since the directory has changed to a temporary one, it will be fine to leave `a.out` in that directory, and we can remove `-o xxx`

https://github.com/llvm/llvm-project/pull/90732