[DebugInfo] Fix reading addresses in DWARFDebugAddr.
authorIgor Kudrin <ikudrin@accesssoftek.com>
Tue, 11 Feb 2020 12:43:20 +0000 (19:43 +0700)
committerIgor Kudrin <ikudrin@accesssoftek.com>
Wed, 12 Feb 2020 06:32:59 +0000 (13:32 +0700)
As addresses in the address tables may have relocations, thus,
the relocations should be resolved to read the correct address.
That is especially important for targets that use RELA relocations
because in that case addends are stored in relocation sections.

Differential Revision: https://reviews.llvm.org/D74404

llvm/lib/DebugInfo/DWARF/DWARFDebugAddr.cpp
llvm/test/tools/llvm-dwarfdump/X86/debug_addr_rela.s [new file with mode: 0644]

index 02b8b8e..ba2c177 100644 (file)
@@ -131,10 +131,7 @@ Error DWARFDebugAddrTable::extract(DWARFDataExtractor Data,
   Data.setAddressSize(HeaderData.AddrSize);
   uint32_t AddrCount = DataSize / HeaderData.AddrSize;
   for (uint32_t I = 0; I < AddrCount; ++I)
-    if (HeaderData.AddrSize == 4)
-      Addrs.push_back(Data.getU32(OffsetPtr));
-    else
-      Addrs.push_back(Data.getU64(OffsetPtr));
+    Addrs.push_back(Data.getRelocatedAddress(OffsetPtr));
   return Error::success();
 }
 
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/debug_addr_rela.s b/llvm/test/tools/llvm-dwarfdump/X86/debug_addr_rela.s
new file mode 100644 (file)
index 0000000..f0058b9
--- /dev/null
@@ -0,0 +1,28 @@
+# RUN: llvm-mc %s -filetype obj -triple x86_64-pc-linux -o - | \
+# RUN:   llvm-dwarfdump -debug-addr - | \
+# RUN:   FileCheck %s
+
+## This checks that we use DWARFDataExtractor::getRelocatedAddress() to read
+## addresses of an address table. In this test, the raw data in the .debug_addr
+## section does not contain the full address, thus, it is required to resolve
+## a RELA relocation to recover the real value.
+
+# CHECK:      .debug_addr contents
+# CHECK-NEXT: length = 0x0000000c, version = 0x0005, addr_size = 0x08, seg_size = 0x00
+# CHECK-NEXT: Addrs: [
+# CHECK-NEXT: 0x000000000000002a
+# CHECK-NEXT: ]
+
+    .text
+    .space  0x2a
+.Lfoo:
+
+    .section .debug_addr,"",@progbits
+    .long   .LAddr0end-.LAddr0version   # Length
+.LAddr0version:
+    .short  5                           # Version
+    .byte   8                           # Address size
+    .byte   0                           # Segment selector size
+.LAddr0table:
+    .quad   .Lfoo
+.LAddr0end: