[llvm] [llvm-objdump] Support --mcpu=help/--mattr=help without -d (PR #165661)

[Ruoyu Qiu via llvm-commits]

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@@ -1,12 +1,38 @@
 # RUN: yaml2obj %s -o %t
-# RUN: llvm-objdump -d %t --mattr=help 2>&1 | FileCheck %s
-# RUN: llvm-objdump -d %t --mcpu=help 2>&1 | FileCheck %s
 # REQUIRES: x86-registered-target
 
+# RUN: llvm-objdump -d %t --mattr=help 2>&1 \
+# RUN:   | FileCheck %s --check-prefixes=CHECK,CHECK-DISASSEMBLE
+# RUN: llvm-objdump -d %t --mcpu=help 2>&1 \
+# RUN:   | FileCheck %s --check-prefixes=CHECK,CHECK-DISASSEMBLE
+
+## The help message can be printed without -d.
+# RUN: llvm-objdump --mattr=help %t 2>&1 \
+# RUN:   | FileCheck %s --check-prefix=CHECK
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cabbaken wrote:

Added.

https://github.com/llvm/llvm-project/pull/165661