[llvm-dwarfdump] pretty-print DW_AT_call_origin reference

[OCHyams]

No description provided.

[llvmbot]

@llvm/pr-subscribers-debuginfo

Author: Orlando Cazalet-Hyams (OCHyams)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/71693.diff

2 Files Affected:

• (modified) llvm/lib/DebugInfo/DWARF/DWARFDie.cpp (+2-1)
• (added) llvm/test/tools/llvm-dwarfdump/X86/prettyprint_call_site.yaml (+87)

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
index fcedef8db82185c..0f01933002c06db 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
@@ -190,7 +190,8 @@ static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
   // We have dumped the attribute raw value. For some attributes
   // having both the raw value and the pretty-printed value is
   // interesting. These attributes are handled below.
-  if (Attr == DW_AT_specification || Attr == DW_AT_abstract_origin) {
+  if (Attr == DW_AT_specification || Attr == DW_AT_abstract_origin ||
+      Attr == DW_AT_call_origin) {
     if (const char *Name =
             Die.getAttributeValueAsReferencedDie(FormValue).getName(
                 DINameKind::LinkageName))
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/prettyprint_call_site.yaml b/llvm/test/tools/llvm-dwarfdump/X86/prettyprint_call_site.yaml
new file mode 100644
index 000000000000000..2e44fcbcb131318
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/X86/prettyprint_call_site.yaml
@@ -0,0 +1,87 @@
+# RUN: yaml2obj %s | llvm-dwarfdump - | FileCheck %s
+
+## Check the name (preferring linkage name) of the DW_AT_call_origin DIE
+## reference is printed after the address.
+
+# CHECK: DW_TAG_call_site
+# CHECK-NEXT: DW_AT_call_origin (0x{{[0-9a-f]+}} "_Z2f2v")
+
+# CHECK: DW_TAG_call_site
+# CHECK-NEXT: DW_AT_call_origin (0x{{[0-9a-f]+}} "f1")
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_X86_64
+DWARF:
+  debug_str:
+    - "_Z2f2v"
+    - "f2"
+    - "f1"
+
+  debug_abbrev:
+    - Table:
+      - Code:            0x0000000000000001
+        Tag:             DW_TAG_compile_unit
+        Children:        DW_CHILDREN_yes
+        Attributes:
+          - Attribute:       DW_AT_low_pc
+            Form:            DW_FORM_addr
+      - Code:            0x0000000000000002
+        Tag:             DW_TAG_subprogram
+        Children:        DW_CHILDREN_yes
+        Attributes:
+          - Attribute:       DW_AT_name
+            Form:            DW_FORM_strp
+          - Attribute:       DW_AT_low_pc
+            Form:            DW_FORM_addr
+          - Attribute:       DW_AT_high_pc
+            Form:            DW_FORM_addr
+      - Code:            0x0000000000000003
+        Tag:             DW_TAG_call_site
+        Children:        DW_CHILDREN_no
+        Attributes:
+          - Attribute:   DW_AT_call_origin
+            Form:        DW_FORM_ref4
+      - Code:            0x0000000000000004
+        Tag:             DW_TAG_subprogram
+        Children:        DW_CHILDREN_no
+        Attributes:
+          - Attribute:       DW_AT_linkage_name
+            Form:            DW_FORM_strp
+          - Attribute:       DW_AT_name
+            Form:            DW_FORM_strp
+          - Attribute:       DW_AT_declaration
+            Form:            DW_FORM_flag_present
+  debug_info:
+    - Length:          0x3b
+      Version:         5
+      UnitType:        0x01 # DW_TU_compile
+      AbbrOffset:      0x0000000000000000
+      AddrSize:        8
+      Entries:
+        - AbbrCode:    0x00000001          # start compile unit
+          Values:                          #
+            - Value:   0x0000000000000000  #
+        - AbbrCode:    0x00000002          ## start f1
+          Values:                          ##
+            - Value:   0x000000000000000a  ##
+            - Value:   0x0000000000001000  ##
+            - Value:   0x0000000000002000  ##
+        - AbbrCode:    0x00000003          ### call site
+          Values:                          ###
+            - Value:   0x0000000000000035  ### (f2)
+        - AbbrCode:    0x00000003          ### call site
+          Values:                          ###
+            - Value:   0x0000000000000015  ### (f1)
+        - AbbrCode:    0x00000000          ## end f1
+          Values:      []                  #
+        - AbbrCode:    0x00000004          ## f2
+          Values:                          ##
+            - Value:   0x0000000000000000  ##
+            - Value:   0x0000000000000007  ##
+        - AbbrCode:    0x00000000          # end compile unit
+          Values:      []
+...

[jryans]

Looks great to me, thanks for improving llvm-dwarfdump output! 😄

If you search the DWARF spec for "a reference", it looks like there are various other attributes that could also be given the same treatment as well... No need to do that in this PR though, just passing it along as a potential further improvement.

[OCHyams]

Looks great to me, thanks for improving llvm-dwarfdump output!

I was inspired by your recent change!

If you search the DWARF spec for "a reference", it looks like there are various other attributes that could also be given the same treatment as well... No need to do that in this PR though, just passing it along as a potential further improvement.

Yeah agreed. FWIW I chose this one as I recently spent a decent amount of time looking at call site info.

Thanks for the review. I'll land this tomorrow to avoid knocking out bots before I sign off.

[dwblaikie]

Looks good to me.

I had a look around and couldn't find some existing code that already tests for whole DWARF attribute classes (like some kind of isReference function) - but maybe it's hiding somewhere, or would be nice to write one eventually.