[llvm] [llvm-readobj] Dump callgraph section info for ELF (PR #157499)

[Paul Kirth via llvm-commits]

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@@ -0,0 +1,146 @@
+## Tests --call-graph-info prints information from call graph section.
+
+# REQUIRES: x86-registered-target
+
+# RUN: llvm-mc %s -filetype=obj -triple=x86_64-pc-linux -o %t
+# RUN: llvm-readelf --call-graph-info %t 2>&1 | count 0
+# RUN: llvm-readelf --elf-output-style=LLVM --call-graph-info %t 2>&1 | FileCheck %s -DFILE=%t --check-prefix=LLVM
+# RUN: llvm-readelf --elf-output-style=JSON --pretty-print --call-graph-info %t 2>&1 | FileCheck %s -DFILE=%t --check-prefix=JSON
+
+# LLVM: warning: '[[FILE]]': .llvm.callgraph section has unknown type id for 2 indirect targets.
+# LLVM-NEXT: CallGraph [
+# LLVM-NEXT:   Function {
+# LLVM-NEXT:     warning: '[[FILE]]': unknown relocation at offset 2
+# LLVM-NEXT:     Version: 0
+# LLVM-NEXT:     IsIndirectTarget: Yes
+# LLVM-NEXT:     TypeId: 0x0
+# LLVM-NEXT:     NumDirectCallees: 1
+# LLVM-NEXT:     DirectCallees [
+# LLVM-NEXT:        {
+# LLVM-NEXT:     warning: '[[FILE]]':  unknown relocation at offset 19
+# LLVM-NEXT:        }
+# LLVM-NEXT:     ]
+# LLVM-NEXT:     NumIndirectTargetTypeIDs: 0
+# LLVM-NEXT:     IndirectTypeIDs: []
+# LLVM-NEXT:   }
+# LLVM-NEXT:   Function {
+# LLVM-NEXT:     warning: '[[FILE]]':  unknown relocation at offset 29
+# LLVM-NEXT:     Version: 0
+# LLVM-NEXT:     IsIndirectTarget: Yes
+# LLVM-NEXT:     TypeId: 0x0
+# LLVM-NEXT:     NumDirectCallees: 0
+# LLVM-NEXT:     DirectCallees [
+# LLVM-NEXT:     ]
+# LLVM-NEXT:     NumIndirectTargetTypeIDs: 1
+# LLVM-NEXT:     IndirectTypeIDs: [0x10]
+# LLVM-NEXT:   }
+# LLVM-NEXT:   Function {
+# LLVM-NEXT:     warning: '[[FILE]]':  unknown relocation at offset 56
+# LLVM-NEXT:     Version: 0
+# LLVM-NEXT:     IsIndirectTarget: Yes
+# LLVM-NEXT:     TypeId: 0x20
+# LLVM-NEXT:     NumDirectCallees: 0
+# LLVM-NEXT:     DirectCallees [
+# LLVM-NEXT:     ]
+# LLVM-NEXT:     NumIndirectTargetTypeIDs: 0
+# LLVM-NEXT:     IndirectTypeIDs: []
+# LLVM-NEXT:   }
+# LLVM-NEXT: ]
+
+# JSON: warning: '[[FILE]]': .llvm.callgraph section has unknown type id for 2 indirect targets.
+# JSON:     "CallGraph": [
+# JSON-NEXT:      {
+# JSON-NEXT:        "Function": {
+# JSON-SAME:     warning: '[[FILE]]': unknown relocation at offset 2
----------------
ilovepi wrote:

Why are we getting this warning here? can we avoid it in this test case, and have specific test cases that should issue the diagnostic? To ensure no warnings occur, you can use the FileCheck `--implicit-check-not "warning:"`. 

https://github.com/llvm/llvm-project/pull/157499