From: Francis Ricci <francisjricci@gmail.com>
Date: Mon, 9 Oct 2017 17:27:47 +0000 (+0000)
Subject: [dsymutil] Emit valid debug locations when no symbol flags are set
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=87b0f4a33cafe87763b4f046bf2fae41adc7f877;p=llvm

[dsymutil] Emit valid debug locations when no symbol flags are set

Summary:
swiftc emits symbols without flags set, which led dsymutil to ignore
them when searching for global symbols, causing dwarf location data
to be omitted. Xcode's dsymutil handles this case correctly, and emits
valid location data. Add this functionality to llvm-dsymutil by
allowing parsing of symbols with no flags set.

Reviewers: aprantl, friss, JDevlieghere

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D38587

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315218 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/test/tools/dsymutil/Inputs/swift-dwarf-loc.macho.x86_64 b/test/tools/dsymutil/Inputs/swift-dwarf-loc.macho.x86_64
new file mode 100755
index 00000000000..b232e509442
Binary files /dev/null and b/test/tools/dsymutil/Inputs/swift-dwarf-loc.macho.x86_64 differ
diff --git a/test/tools/dsymutil/Inputs/swift-dwarf-loc.macho.x86_64.o b/test/tools/dsymutil/Inputs/swift-dwarf-loc.macho.x86_64.o
new file mode 100644
index 00000000000..2e34ce3de5b
Binary files /dev/null and b/test/tools/dsymutil/Inputs/swift-dwarf-loc.macho.x86_64.o differ
diff --git a/test/tools/dsymutil/X86/swift-dwarf-loc.test b/test/tools/dsymutil/X86/swift-dwarf-loc.test
new file mode 100644
index 00000000000..29310cae6a4
--- /dev/null
+++ b/test/tools/dsymutil/X86/swift-dwarf-loc.test
@@ -0,0 +1,37 @@
+RUN: llvm-dsymutil -oso-prepend-path %p/../Inputs %p/../Inputs/swift-dwarf-loc.macho.x86_64 -no-output -verbose | FileCheck %s
+
+This test checks that dsymutil generates a valid dwarf location for a symbol with no flags set.
+
+The following IR was compiled for x86_64-apple:
+; ModuleID = '-'
+source_filename = "-"
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.12"
+
+%TSi = type <{ i64 }>
+
+@_var = hidden global %TSi zeroinitializer, align 8, !dbg !0
+
+!llvm.dbg.cu = !{!8}
+!llvm.module.flags = !{!11, !12}
+
+!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
+!1 = distinct !DIGlobalVariable(name: "x", linkageName: "_var", scope: !2, file: !3, line: 1, type: !4, isLocal: false, isDefinition: true)
+!2 = !DIModule(scope: null, name: "main")
+!3 = !DIFile(filename: "<stdin>", directory: "")
+!4 = !DICompositeType(tag: DW_TAG_structure_type, name: "Int", scope: !6, file: !5, size: 64, elements: !7, runtimeLang: DW_LANG_Swift, identifier: "_T0SiD")
+!5 = !DIFile(filename: "foo", directory: "/tmp")
+!6 = !DIModule(scope: null, name: "foo", includePath: "")
+!7 = !{}
+!8 = distinct !DICompileUnit(language: DW_LANG_Swift, file: !9, producer: "swiftc", isOptimized: false, flags: "", runtimeVersion: 4, emissionKind: FullDebug, enums: !7, globals: !10, imports: null)
+!9 = !DIFile(filename: "/tmp", directory: "")
+!10 = !{!0}
+!11 = !{i32 2, !"Dwarf Version", i32 4}
+!12 = !{i32 2, !"Debug Info Version", i32 3}
+
+Compiled with: llc -filetype=obj %p/../Inputs/swift-dwarf-loc.ll -mtriple x86_64-apple-darwin
+Linked with: ld -dylib %T/swift-dwarf-loc.o -arch x86_64 -lSystem -macosx_version_min 10.9.0
+
+CHECK: __var,
+CHECK-NOT: __var,{{.*}}binAddr: 0x0000000000000000
+CHECK-NOT: __var{{.*}} => 0000000000000000
diff --git a/tools/dsymutil/MachODebugMapParser.cpp b/tools/dsymutil/MachODebugMapParser.cpp
index 79b19137119..0cd6a89cc01 100644
--- a/tools/dsymutil/MachODebugMapParser.cpp
+++ b/tools/dsymutil/MachODebugMapParser.cpp
@@ -482,7 +482,9 @@ void MachODebugMapParser::loadMainBinarySymbols(
     // are the only ones that need to be queried because the address
     // of common data won't be described in the debug map. All other
     // addresses should be fetched for the debug map.
-    if (!(Sym.getFlags() & SymbolRef::SF_Global))
+    uint8_t SymType =
+        MainBinary.getSymbolTableEntry(Sym.getRawDataRefImpl()).n_type;
+    if (!(SymType & (MachO::N_EXT | MachO::N_PEXT)))
       continue;
     Expected<section_iterator> SectionOrErr = Sym.getSection();
     if (!SectionOrErr) {