[lld] [llvm] [lld][AArch64][Build Attributes] Add support for AArch64 Build Attributes (PR #144082)

[Peter Smith via llvm-commits]

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+// RUN: rm -rf %t && split-file %s %t && cd %t
+
+// RUN: llvm-mc -triple=aarch64 -filetype=obj %s -o %t11.o
+// RUN: llvm-mc -triple=aarch64 -filetype=obj merged-mixed-2.s -o %t12.o
+// RUN: llvm-mc -triple=aarch64 -filetype=obj merged-mixed-3.s -o %t13.o
+// RUN: ld.lld -r %t11.o %t12.o %t13.o -o %t.merged1.o
+// RUN: llvm-readelf -n %t.merged1.o | FileCheck %s --check-prefix=NOTE-MIXED
+
+// NOTE-MIXED: Displaying notes found in: .note.gnu.property
+// NOTE-MIXED-NEXT:   Owner                Data size 	Description
+// NOTE-MIXED-NEXT:   GNU                  0x00000028	NT_GNU_PROPERTY_TYPE_0 (property note)
+// NOTE-MIXED-NEXT:     Properties:    aarch64 feature: BTI, PAC
+// NOTE-MIXED-NEXT:         AArch64 PAuth ABI core info: platform 0x31 (unknown), version 0x13
+
+/// The Build attributes section appearing in the output of
+/// llvm-mc should not appear in the output of lld, because
+/// AArch64 build attributes are being transformed into .gnu.properties.
+
+// CHECK: .note.gnu.property
+// CHECK-NOT: .ARM.attributes
+
+.aeabi_subsection aeabi_pauthabi, required, uleb128
+.aeabi_attribute Tag_PAuth_Platform, 49
+.aeabi_attribute Tag_PAuth_Schema, 19
+.aeabi_subsection aeabi_feature_and_bits, optional, uleb128
+.aeabi_attribute Tag_Feature_BTI, 1
+.aeabi_attribute Tag_Feature_PAC, 1
+.aeabi_attribute Tag_Feature_GCS, 1
+
+
+//--- merged-mixed-2.s
+.section ".note.gnu.property", "a"
+  .long 4           // Name length is always 4 ("GNU")
+  .long end - begin // Data length
+  .long 5           // Type: NT_GNU_PROPERTY_TYPE_0
+  .asciz "GNU"      // Name
+  .p2align 3
+begin:
+  .long 0xc0000000 // GNU_PROPERTY_AARCH64_FEATURE_1_AND
+  .long 4
+  .long 7          // GNU_PROPERTY_AARCH64_FEATURE_1_BTI, PAC and GCS
+  .long 0
+  // PAuth ABI property note
+  .long 0xc0000001  // Type: GNU_PROPERTY_AARCH64_FEATURE_PAUTH
+  .long 16          // Data size
+  .quad 49          // PAuth ABI platform
+  .quad 19          // PAuth ABI version
+  .p2align 3        // Align to 8 byte for 64 bit
+end:
+
+//--- merged-mixed-3.s
+.section .note.gnu.property, "a"
+  .align 4
+  .long 4                      // namesz
+  .long 0x10                   // descsz
+  .long 5                      // type (NT_GNU_PROPERTY_TYPE_0)
+  .asciz "GNU"                // name (null-terminated)
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smithp35 wrote:

comment not indented to same level.

https://github.com/llvm/llvm-project/pull/144082