[llvm] Support big endian in llvm-symbolizer's data location dwarf info parser (PR #67284)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-binary-utilities

<details>
<summary>Changes</summary>

For now, data location expression is hard coded to little endian. We are going to support sanitizers on AIX which is big endian. Support big endian too in the data location expression parser of llvm-symbolizer.

Currently obj2yaml/yaml2obj can not support debug info for xcoff, so I used an object. Will update this once obj2yaml/yaml2obj are ready for XCOFF objects with DWARF info

---
Full diff: https://github.com/llvm/llvm-project/pull/67284.diff


3 Files Affected:

- (modified) llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp (+1-1) 
- (added) llvm/test/tools/llvm-symbolizer/Inputs/xcoff-dwarf.o () 
- (added) llvm/test/tools/llvm-symbolizer/xcoff.test (+42) 


``````````diff
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
index 387345a4ac2d601..0cd45bde3e25349 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
@@ -784,7 +784,7 @@ void DWARFUnit::updateVariableDieMap(DWARFDie Die) {
 
   for (const DWARFLocationExpression &Location : *Locations) {
     uint8_t AddressSize = getAddressByteSize();
-    DataExtractor Data(Location.Expr, /*IsLittleEndian=*/true, AddressSize);
+    DataExtractor Data(Location.Expr, isLittleEndian(), AddressSize);
     DWARFExpression Expr(Data, AddressSize);
     auto It = Expr.begin();
     if (It == Expr.end())
diff --git a/llvm/test/tools/llvm-symbolizer/Inputs/xcoff-dwarf.o b/llvm/test/tools/llvm-symbolizer/Inputs/xcoff-dwarf.o
new file mode 100644
index 000000000000000..04326b6ccedd046
Binary files /dev/null and b/llvm/test/tools/llvm-symbolizer/Inputs/xcoff-dwarf.o differ
diff --git a/llvm/test/tools/llvm-symbolizer/xcoff.test b/llvm/test/tools/llvm-symbolizer/xcoff.test
new file mode 100644
index 000000000000000..26a57f1f87b16bd
--- /dev/null
+++ b/llvm/test/tools/llvm-symbolizer/xcoff.test
@@ -0,0 +1,42 @@
+
+RUN: llvm-symbolizer --obj=%p/Inputs/xcoff-dwarf.o 'DATA 0x60' \
+RUN:    'DATA 0x61' 'DATA 0x64' 'DATA 0X68' 'DATA 0x90' 'DATA 0x94' \
+RUN:    'DATA 0X98' | FileCheck %s
+
+CHECK: bss_global
+CHECK-NEXT: 96 4
+CHECK-NEXT: /t.cpp:1
+CHECK-EMPTY:
+
+CHECK: bss_global
+CHECK-NEXT: 96 4
+CHECK-NEXT: /t.cpp:1
+CHECK-EMPTY:
+
+CHECK: data_global
+CHECK-NEXT: 100 4
+CHECK-NEXT: /t.cpp:2
+CHECK-EMPTY:
+
+CHECK: str
+CHECK-NEXT: 104 4
+CHECK-NEXT: /t.cpp:4
+CHECK-EMPTY:
+
+FIXME: fix the wrong size 152
+CHECK: f()::function_global
+CHECK-NEXT: 144 152
+CHECK-NEXT: /t.cpp:8
+CHECK-EMPTY:
+
+FIXME: fix the wrong size 152
+CHECK: beta
+CHECK-NEXT: 148 152
+CHECK-NEXT: /t.cpp:13
+CHECK-EMPTY:
+
+FIXME: fix the wrong size 152
+CHECK: alpha
+CHECK-NEXT: 152 152
+CHECK-NEXT: /t.cpp:12
+CHECK-EMPTY:

``````````

</details>


https://github.com/llvm/llvm-project/pull/67284