[lld] [llvm] [RISCV] Support RISCV Atomics ABI attributes (PR #84597)

[Fangrui Song via llvm-commits]

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@@ -44,6 +44,39 @@
 # RUN: not ld.lld a.o b.o c.o diff_stack_align.o -o /dev/null 2>&1 | FileCheck %s --check-prefix=STACK_ALIGN --implicit-check-not=error:
 # STACK_ALIGN: error: diff_stack_align.o:(.riscv.attributes) has stack_align=32 but a.o:(.riscv.attributes) has stack_align=16
 
+## merging atomic_abi values for A6C and A7 lead to an error.
+# RUN: llvm-mc -filetype=obj -triple=riscv64  atomic_abi_A6C.s -o atomic_abi_A6C.o
+# RUN: llvm-mc -filetype=obj -triple=riscv64  atomic_abi_A7.s -o atomic_abi_A7.o
+# RUN: not ld.lld atomic_abi_A6C.o atomic_abi_A7.o -o /dev/null 2>&1 | FileCheck %s --check-prefix=ATOMIC_ABI_ERROR --implicit-check-not=error:
+# ATOMIC_ABI_ERROR: error: atomic_abi_A6C.o:(.riscv.attributes) has atomic_abi=1 but atomic_abi_A7.o:(.riscv.attributes) has atomic_abi=3
+
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MaskRay wrote:

We don't use double blank lines

https://github.com/llvm/llvm-project/pull/84597