[llvm] r358931 - DebugInfo: Emit only one kind of accelerated access/name table

Tue Apr 23 08:01:21 PDT 2019

Yep, I can observe a change in size of apple_names under this patch.
Reverted in r358997 while I investigate.

On Tue, Apr 23, 2019 at 2:50 AM Pavel Labath <labath at google.com> wrote:
>
> I'm pretty sure this commit is related. The (still experimental) lldb
> bot started getting failures right after this commit
> <http://lab.llvm.org:8014/builders/lldb-x86_64-debian/builds/468> and
> the failures are localized to accelerator table tests. The apple lldb
> green dragon bots also started going crazy around this commit
> <http://green.lab.llvm.org/green/job/lldb-cmake/24354/>, though they
> were red for other reasons too.
>
> Based on my small investigation, I think the problem is some bad
> interaction between this patch and the .apple_*** accelerator tables.
> After this patch clang starts to emit empty accel tables for darwin
> targets. It's possible to "fix" this by manually adding
> -gno-gnu-pubnames to the compiler invocation, but I don't expect that
> was the intention here. :)
>
> On Tue, 23 Apr 2019 at 04:11, Adrian Prantl via llvm-commits
> <llvm-commits at lists.llvm.org> wrote:
> >
> > I haven't tried to reproduce the failure yet, but do you think it's possible this caused the debuginfo-tests to fail?
> >
> > http://lab.llvm.org:8080/green/job/clang-stage1-configure-RA/55815/
> >
> > It seems to be the only non-NFC change in the blamelist.
> >
> > -- adrian
> >
> > On Apr 22, 2019, at 3:45 PM, David Blaikie via llvm-commits <llvm-commits at lists.llvm.org> wrote:
> >
> > Author: dblaikie
> > Date: Mon Apr 22 15:45:11 2019
> > New Revision: 358931
> >
> > URL: http://llvm.org/viewvc/llvm-project?rev=358931&view=rev
> > Log:
> > DebugInfo: Emit only one kind of accelerated access/name table
> >
> > Currently to opt in to debug_names in DWARFv5, the IR must contain
> > 'nameTableKind: Default' which also enables debug_pubnames.
> >
> > Instead, only allow one of {debug_names, apple_names, debug_pubnames,
> > debug_gnu_pubnames}.
> >
> > nameTableKind: Default gives debug_names in DWARFv5 and greater,
> > debug_pubnames in v4 and earlier - and apple_names when tuning for lldb
> > on MachO.
> > nameTableKind: GNU always gives gnu_pubnames
> >
> > Added:
> >    llvm/trunk/test/DebugInfo/X86/gnu-names.ll
> >      - copied, changed from r358805, llvm/trunk/test/DebugInfo/X86/accel-tables.ll
> > Modified:
> >    llvm/trunk/lib/CodeGen/AsmPrinter/AccelTable.cpp
> >    llvm/trunk/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
> >    llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
> >    llvm/trunk/test/DebugInfo/X86/accel-tables.ll
> >
> > Modified: llvm/trunk/lib/CodeGen/AsmPrinter/AccelTable.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/AccelTable.cpp?rev=358931&r1=358930&r2=358931&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/CodeGen/AsmPrinter/AccelTable.cpp (original)
> > +++ llvm/trunk/lib/CodeGen/AsmPrinter/AccelTable.cpp Mon Apr 22 15:45:11 2019
> > @@ -556,8 +556,8 @@ void llvm::emitDWARF5AccelTable(
> >   SmallVector<unsigned, 1> CUIndex(CUs.size());
> >   int Count = 0;
> >   for (const auto &CU : enumerate(CUs)) {
> > -    if (CU.value()->getCUNode()->getNameTableKind() ==
> > -        DICompileUnit::DebugNameTableKind::None)
> > +    if (CU.value()->getCUNode()->getNameTableKind() !=
> > +        DICompileUnit::DebugNameTableKind::Default)
> >       continue;
> >     CUIndex[CU.index()] = Count++;
> >     assert(CU.index() == CU.value()->getUniqueID());
> >
> > Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp?rev=358931&r1=358930&r2=358931&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp (original)
> > +++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp Mon Apr 22 15:45:11 2019
> > @@ -1036,7 +1036,9 @@ bool DwarfCompileUnit::hasDwarfPubSectio
> >     return true;
> >   case DICompileUnit::DebugNameTableKind::Default:
> >     return DD->tuneForGDB() && !includeMinimalInlineScopes() &&
> > -           !CUNode->isDebugDirectivesOnly();
> > +           !CUNode->isDebugDirectivesOnly() &&
> > +           DD->getAccelTableKind() != AccelTableKind::Apple &&
> > +           DD->getDwarfVersion() < 5;
> >   }
> >   llvm_unreachable("Unhandled DICompileUnit::DebugNameTableKind enum");
> > }
> >
> > Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp?rev=358931&r1=358930&r2=358931&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp (original)
> > +++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp Mon Apr 22 15:45:11 2019
> > @@ -2765,6 +2765,9 @@ void DwarfDebug::addAccelNameImpl(const
> >       CU.getNameTableKind() == DICompileUnit::DebugNameTableKind::None)
> >     return;
> >
> > +  if (CU.getNameTableKind() == DICompileUnit::DebugNameTableKind::GNU)
> > +    return;
> > +
> >   DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
> >   DwarfStringPoolEntryRef Ref = Holder.getStringPool().getEntry(*Asm, Name);
> >
> >
> > Modified: llvm/trunk/test/DebugInfo/X86/accel-tables.ll
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/X86/accel-tables.ll?rev=358931&r1=358930&r2=358931&view=diff
> > ==============================================================================
> > --- llvm/trunk/test/DebugInfo/X86/accel-tables.ll (original)
> > +++ llvm/trunk/test/DebugInfo/X86/accel-tables.ll Mon Apr 22 15:45:11 2019
> > @@ -4,11 +4,11 @@
> > ; RUN: llc -mtriple=x86_64-apple-darwin12 -filetype=obj < %s \
> > ; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=APPLE %s
> > ; RUN: llc -mtriple=x86_64-apple-darwin12 -filetype=obj -debugger-tune=gdb < %s \
> > -; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=NONE %s
> > +; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=PUB %s
> >
> > ; Linux does has debug_names tables only if we explicitly tune for lldb
> > ; RUN: llc -mtriple=x86_64-pc-linux -filetype=obj < %s \
> > -; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=NONE %s
> > +; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=PUB %s
> > ; RUN: llc -mtriple=x86_64-pc-linux -filetype=obj -debugger-tune=lldb < %s \
> > ; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=DEBUG_NAMES %s
> >
> > @@ -23,15 +23,25 @@
> > ; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=APPLE %s
> >
> > ; APPLE-NOT: debug_names
> > +; APPLE-NOT: pubnames
> > ; APPLE: apple_names
> > ; APPLE-NOT: debug_names
> > +; APPLE-NOT: pubnames
> > +
> > +; PUB-NOT: apple_names
> > +; PUB-NOT: debug_names
> > +; PUB: pubnames
> > +; PUB-NOT: apple_names
> > +; PUB-NOT: debug_names
> >
> > ; NONE-NOT: apple_names
> > ; NONE-NOT: debug_names
> >
> > ; DEBUG_NAMES-NOT: apple_names
> > +; DEBUG_NAMES-NOT: pubnames
> > ; DEBUG_NAMES: debug_names
> > ; DEBUG_NAMES-NOT: apple_names
> > +; DEBUG_NAMES-NOT: pubnames
> >
> > @var = thread_local global i32 0, align 4, !dbg !0
> >
> >
> > Copied: llvm/trunk/test/DebugInfo/X86/gnu-names.ll (from r358805, llvm/trunk/test/DebugInfo/X86/accel-tables.ll)
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/X86/gnu-names.ll?p2=llvm/trunk/test/DebugInfo/X86/gnu-names.ll&p1=llvm/trunk/test/DebugInfo/X86/accel-tables.ll&r1=358805&r2=358931&rev=358931&view=diff
> > ==============================================================================
> > --- llvm/trunk/test/DebugInfo/X86/accel-tables.ll (original)
> > +++ llvm/trunk/test/DebugInfo/X86/gnu-names.ll Mon Apr 22 15:45:11 2019
> > @@ -4,13 +4,13 @@
> > ; RUN: llc -mtriple=x86_64-apple-darwin12 -filetype=obj < %s \
> > ; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=APPLE %s
> > ; RUN: llc -mtriple=x86_64-apple-darwin12 -filetype=obj -debugger-tune=gdb < %s \
> > -; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=NONE %s
> > +; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=GNU %s
> >
> > ; Linux does has debug_names tables only if we explicitly tune for lldb
> > ; RUN: llc -mtriple=x86_64-pc-linux -filetype=obj < %s \
> > -; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=NONE %s
> > +; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=GNU %s
> > ; RUN: llc -mtriple=x86_64-pc-linux -filetype=obj -debugger-tune=lldb < %s \
> > -; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=DEBUG_NAMES %s
> > +; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=GNU %s
> >
> > ; No accelerator tables if type units are enabled, as DWARF v4 type units are
> > ; not compatible with accelerator tables.
> > @@ -23,16 +23,20 @@
> > ; RUN:   | llvm-readobj -sections - | FileCheck --check-prefix=APPLE %s
> >
> > ; APPLE-NOT: debug_names
> > +; APPLE-NOT: pubnames
> > ; APPLE: apple_names
> > ; APPLE-NOT: debug_names
> > +; APPLE-NOT: pubnames
> > +
> > +; GNU-NOT: apple_names
> > +; GNU-NOT: debug_names
> > +; GNU: gnu_pub
> > +; GNU-NOT: apple_names
> > +; GNU-NOT: debug_names
> >
> > ; NONE-NOT: apple_names
> > ; NONE-NOT: debug_names
> >
> > -; DEBUG_NAMES-NOT: apple_names
> > -; DEBUG_NAMES: debug_names
> > -; DEBUG_NAMES-NOT: apple_names
> > -
> > @var = thread_local global i32 0, align 4, !dbg !0
> >
> > ; Function Attrs: norecurse nounwind readnone uwtable
> > @@ -54,7 +58,7 @@ attributes #1 = { norecurse uwtable }
> >
> > !0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
> > !1 = distinct !DIGlobalVariable(name: "var", scope: !2, file: !3, line: 1, type: !6, isLocal: false, isDefinition: true)
> > -!2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !3, producer: "clang version 7.0.0 (trunk 322268) (llvm/trunk 322267)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5)
> > +!2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !3, producer: "clang version 7.0.0 (trunk 322268) (llvm/trunk 322267)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5, nameTableKind: GNU)
> > !3 = !DIFile(filename: "debugger-tune.cpp", directory: "/tmp")
> > !4 = !{}
> > !5 = !{!0}
> >
> >
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> >
> >
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