[llvm] [mlir] [Dwarf] Support `__ptrauth` qualifier in metadata nodes (PR #83862)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,70 @@
+; RUN: llc %s -filetype=obj -mtriple arm64e-apple-darwin -o - \
+; RUN:   | llvm-dwarfdump - | FileCheck %s
+
+; CHECK: DW_AT_type	(0x{{0+}}[[TY:.*]] "void *__ptrauth(4, 0, 0x04d2)")
+; CHECK: 0x{{0+}}[[TY]]: DW_TAG_LLVM_ptrauth_type
+; CHECK-NEXT: DW_AT_type {{.*}}"void *"
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_key (0x04)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_extra_discriminator (0x04d2)
+
+; CHECK: DW_AT_type	(0x{{0+}}[[TY:.*]] "void *__ptrauth(4, 1, 0x04d3)")
+; CHECK: 0x{{0+}}[[TY]]: DW_TAG_LLVM_ptrauth_type
+; CHECK-NEXT: DW_AT_type {{.*}}"void *"
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_key (0x04)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_address_discriminated (true)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_extra_discriminator (0x04d3)
+
+; CHECK: DW_AT_type	(0x{{0+}}[[TY:.*]] "void *__ptrauth(4, 1, 0x04d4, "isa-pointer")")
+; CHECK: 0x{{0+}}[[TY]]: DW_TAG_LLVM_ptrauth_type
+; CHECK-NEXT: DW_AT_type {{.*}}"void *"
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_key (0x04)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_address_discriminated (true)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_extra_discriminator (0x04d4)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_isa_pointer	(true)
+
+; CHECK: DW_AT_type	(0x{{0+}}[[TY:.*]] "void *__ptrauth(4, 1, 0x04d5, "authenticates-null-values")")
+; CHECK: 0x{{0+}}[[TY]]: DW_TAG_LLVM_ptrauth_type
+; CHECK-NEXT: DW_AT_type {{.*}}"void *"
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_key (0x04)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_address_discriminated (true)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_extra_discriminator (0x04d5)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_authenticates_null_values	(true)
+
+; CHECK: DW_AT_type	(0x{{0+}}[[TY:.*]] "void *__ptrauth(4, 1, 0x04d6, "isa-pointer,authenticates-null-values")")
+; CHECK: 0x{{0+}}[[TY]]: DW_TAG_LLVM_ptrauth_type
+; CHECK-NEXT: DW_AT_type {{.*}}"void *"
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_key (0x04)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_address_discriminated (true)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_extra_discriminator (0x04d6)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_isa_pointer	(true)
+; CHECK-NEXT: DW_AT_LLVM_ptrauth_authenticates_null_values	(true)
+
+target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
+
+ at p = common global i8* null, align 8, !dbg !0
----------------
MaskRay wrote:

`i8*` indicates a typed pointer, which LLVM is migrating away. Use `ptr`.
Consider a non-common linkage. COMMON linkage is also obsoleted.

https://github.com/llvm/llvm-project/pull/83862