[llvm] a7ceef9 - DebugInfo/Symbolize: Exclude ARM mapping symbols for .symtab symbolization after D95916

[Fangrui Song via llvm-commits]

Author: Fangrui Song
Date: 2021-02-12T11:04:20-08:00
New Revision: a7ceef9254ad1ec112906f53ac9cae2f0a37e4bb

URL: https://github.com/llvm/llvm-project/commit/a7ceef9254ad1ec112906f53ac9cae2f0a37e4bb
DIFF: https://github.com/llvm/llvm-project/commit/a7ceef9254ad1ec112906f53ac9cae2f0a37e4bb.diff

LOG: DebugInfo/Symbolize: Exclude ARM mapping symbols for .symtab symbolization after D95916

Their names don't convey much information, so they should be excluded.
The behavior matches addr2line.

Differential Revision: https://reviews.llvm.org/D96617

Added: 
    llvm/test/DebugInfo/Symbolize/ELF/arm-mapping-symbol.s

Modified: 
    llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp b/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp
index 4a9b119e5dad..d7519998c67e 100644
--- a/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp
+++ b/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp
@@ -174,6 +174,11 @@ Error SymbolizableObjectFile::addSymbol(const SymbolRef &Symbol,
     if (Type != ELF::STT_NOTYPE && Type != ELF::STT_FUNC &&
         Type != ELF::STT_OBJECT && Type != ELF::STT_GNU_IFUNC)
       return Error::success();
+    // Some STT_NOTYPE symbols are not desired. This excludes STT_SECTION and
+    // ARM mapping symbols.
+    uint32_t Flags = cantFail(Symbol.getFlags());
+    if (Flags & SymbolRef::SF_FormatSpecific)
+      return Error::success();
   } else if (SymbolType != SymbolRef::ST_Function &&
              SymbolType != SymbolRef::ST_Data) {
     return Error::success();

diff  --git a/llvm/test/DebugInfo/Symbolize/ELF/arm-mapping-symbol.s b/llvm/test/DebugInfo/Symbolize/ELF/arm-mapping-symbol.s
new file mode 100644
index 000000000000..810ae4f5b8bd
--- /dev/null
+++ b/llvm/test/DebugInfo/Symbolize/ELF/arm-mapping-symbol.s
@@ -0,0 +1,19 @@
+# REQUIRES: arm-registered-target
+## Ignore ARM mapping symbols (with a prefix of $a, $d or $t).
+
+# RUN: llvm-mc -filetype=obj -triple=armv7-none-linux %s -o %t
+# RUN: llvm-symbolizer --obj=%t 4 8 | FileCheck %s
+# RUN: llvm-mc -filetype=obj -triple=thumbv7-none-linux %s -o %tthumb
+# RUN: llvm-symbolizer --obj=%tthumb 4 8 | FileCheck %s
+
+# CHECK:       foo
+# CHECK-NEXT:  ??:0:0
+# CHECK-EMPTY:
+# CHECK-NEXT:  foo
+# CHECK-NEXT:  ??:0:0
+
+.globl foo
+foo:
+  .word 32
+  nop
+  .word 32