From: Alexey Samsonov <samsonov@google.com>
Date: Fri, 18 Apr 2014 22:22:44 +0000 (+0000)
Subject: [llvm-symbolizer] Print file/line for a PC even if there is no DIE describing it.
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=e0d2d7fb26a2dac464f6e245594176a2a7f1ccf7;p=oota-llvm.git

[llvm-symbolizer] Print file/line for a PC even if there is no DIE describing it.

This is important for symbolizing executables with debug info in
unavailable .dwo files. Even if all DIE entries are missing, we can
still symbolize an address: function name can be fetched from symbol table,
and file/line info can be fetched from line table.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206665 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/DebugInfo/DWARFContext.cpp b/lib/DebugInfo/DWARFContext.cpp
index 50ec4d3cb47..148d56800f8 100644
--- a/lib/DebugInfo/DWARFContext.cpp
+++ b/lib/DebugInfo/DWARFContext.cpp
@@ -545,18 +545,32 @@ DILineInfoTable DWARFContext::getLineInfoForAddressRange(uint64_t Address,
 
 DIInliningInfo DWARFContext::getInliningInfoForAddress(uint64_t Address,
     DILineInfoSpecifier Specifier) {
+  DIInliningInfo InliningInfo;
+
   DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
   if (!CU)
-    return DIInliningInfo();
+    return InliningInfo;
 
+  const DWARFLineTable *LineTable = nullptr;
+  const bool NeedsAbsoluteFilePath =
+      Specifier.needs(DILineInfoSpecifier::AbsoluteFilePath);
   const DWARFDebugInfoEntryInlinedChain &InlinedChain =
       CU->getInlinedChainForAddress(Address);
-  if (InlinedChain.DIEs.size() == 0)
-    return DIInliningInfo();
+  if (InlinedChain.DIEs.size() == 0) {
+    // If there is no DIE for address (e.g. it is in unavailable .dwo file),
+    // try to at least get file/line info from symbol table.
+    if (Specifier.needs(DILineInfoSpecifier::FileLineInfo)) {
+      DILineInfo Frame;
+      LineTable = getLineTableForCompileUnit(CU);
+      if (getFileLineInfoForCompileUnit(CU, LineTable, Address,
+                                        NeedsAbsoluteFilePath, Frame)) {
+        InliningInfo.addFrame(Frame);
+      }
+    }
+    return InliningInfo;
+  }
 
-  DIInliningInfo InliningInfo;
   uint32_t CallFile = 0, CallLine = 0, CallColumn = 0;
-  const DWARFLineTable *LineTable = nullptr;
   for (uint32_t i = 0, n = InlinedChain.DIEs.size(); i != n; i++) {
     const DWARFDebugInfoEntryMinimal &FunctionDIE = InlinedChain.DIEs[i];
     DILineInfo Frame;
@@ -566,16 +580,13 @@ DIInliningInfo DWARFContext::getInliningInfoForAddress(uint64_t Address,
         Frame.FunctionName = Name;
     }
     if (Specifier.needs(DILineInfoSpecifier::FileLineInfo)) {
-      const bool NeedsAbsoluteFilePath =
-          Specifier.needs(DILineInfoSpecifier::AbsoluteFilePath);
       if (i == 0) {
         // For the topmost frame, initialize the line table of this
         // compile unit and fetch file/line info from it.
         LineTable = getLineTableForCompileUnit(CU);
         // For the topmost routine, get file/line info from line table.
         getFileLineInfoForCompileUnit(CU, LineTable, Address,
-                                      NeedsAbsoluteFilePath,
-                                      Frame);
+                                      NeedsAbsoluteFilePath, Frame);
       } else {
         // Otherwise, use call file, call line and call column from
         // previous DIE in inlined chain.
diff --git a/test/DebugInfo/Inputs/llvm-symbolizer-dwo-test b/test/DebugInfo/Inputs/llvm-symbolizer-dwo-test
new file mode 100755
index 00000000000..c28c3d277a7
Binary files /dev/null and b/test/DebugInfo/Inputs/llvm-symbolizer-dwo-test differ
diff --git a/test/DebugInfo/Inputs/llvm-symbolizer-dwo-test.cc b/test/DebugInfo/Inputs/llvm-symbolizer-dwo-test.cc
new file mode 100644
index 00000000000..ea0967a263a
--- /dev/null
+++ b/test/DebugInfo/Inputs/llvm-symbolizer-dwo-test.cc
@@ -0,0 +1,18 @@
+int f(int a, int b) {
+  return a + b;
+}
+
+int g(int a) {
+  return a + 1;
+}
+
+
+int main() {
+  return f(2, g(2));
+}
+
+// Built with Clang 3.5.0:
+// $ mkdir -p /tmp/dbginfo
+// $ cp llvm-symbolizer-dwo-test.cc /tmp/dbginfo
+// $ cd /tmp/dbginfo
+// $ clang -gsplit-dwarf llvm-symbolizer-dwo-test.cc
diff --git a/test/DebugInfo/llvm-symbolizer.test b/test/DebugInfo/llvm-symbolizer.test
index 4b532f3e4aa..6d51fe96c48 100644
--- a/test/DebugInfo/llvm-symbolizer.test
+++ b/test/DebugInfo/llvm-symbolizer.test
@@ -8,6 +8,7 @@ RUN: echo "\"%p/Inputs/dwarfdump-test3.elf-x86-64 space\" 0x633" >> %t.input
 RUN: echo "%p/Inputs/macho-universal 0x1f84" >> %t.input
 RUN: echo "%p/Inputs/macho-universal:i386 0x1f67" >> %t.input
 RUN: echo "%p/Inputs/macho-universal:x86_64 0x100000f05" >> %t.input
+RUN: echo "%p/Inputs/llvm-symbolizer-dwo-test 0x400514" >> %t.input
 
 RUN: llvm-symbolizer --functions --inlining --demangle=false \
 RUN:    --default-arch=i386 < %t.input | FileCheck %s
@@ -48,6 +49,9 @@ CHECK:      main
 CHECK:      _Z3inci
 CHECK:      _Z3inci
 
+CHECK: main
+CHECK-NEXT: llvm-symbolizer-dwo-test.cc:11
+
 RUN: echo "unexisting-file 0x1234" > %t.input2
 RUN: llvm-symbolizer < %t.input2