Commit Graph

3869 Commits

Author SHA1 Message Date
Strahinja Petrovic 29202f6dc1 Fixed reverted commit rL312318
This patch contains fix for reverted commit
rL312318 which was causing failure due to use
of unchecked dyn_cast to CIInit.

Patch by: Nikola Prica.

llvm-svn: 313870
2017-09-21 10:04:02 +00:00
Reid Kleckner 26fa1bf4da Re-land "Fix Bug 30978 by emitting cv file checksums."
This reverts r313431 and brings back r313374 with a fix to write
checksums as binary data and not ASCII hex strings.

llvm-svn: 313657
2017-09-19 18:14:45 +00:00
Eric Beckmann 913213c8ae Revert "Fix Bug 30978 by emitting cv file checksums."
This reverts commit 6389e7aa724ea7671d096f4770f016c3d86b0d54.

There is a bug in this implementation where the string value of the
checksum is outputted, instead of the actual hex bytes.  Therefore the
checksum is incorrect, and this prevent pdbs from being loaded by visual
studio.  Revert this until the checksum is emitted correctly.

llvm-svn: 313431
2017-09-16 01:14:36 +00:00
Sam Clegg 66a99e41cd Change encodeU/SLEB128 to pad to certain number of bytes
Previously the 'Padding' argument was the number of padding
bytes to add. However most callers that use 'Padding' know
how many overall bytes they need to write.  With the previous
code this would mean encoding the LEB once to find out how
many bytes it would occupy and then using this to calulate
the 'Padding' value.

See: https://reviews.llvm.org/D36595

Differential Revision: https://reviews.llvm.org/D37494

llvm-svn: 313393
2017-09-15 20:34:47 +00:00
Eric Beckmann 349746f044 Fix Bug 30978 by emitting cv file checksums.
Summary:
The checksums had already been placed in the IR, this patch allows
MCCodeView to actually write it out to an MCStreamer.

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37157

llvm-svn: 313374
2017-09-15 18:20:28 +00:00
Reid Kleckner 87288b98b6 [codeview] Use a type index of zero for static method "this" types
Otherwise VS won't show anything in the autos or watch window of static
methods.

llvm-svn: 313329
2017-09-15 00:59:07 +00:00
Dean Michael Berris 01fd7c8bd4 [XRay][CodeGen] Use the current function symbol as the associated symbol for the instrumentation map
Summary:
XRay had been assuming that the previous section is the "text" section
of the function when lowering the instrumentation map. Unfortunately
this is not a safe assumption, because we may be coming from lowering
debug type information for the function being lowered.

This fixes an issue with combining -gsplit-dwarf, -generate-type-units,
-debug-compile and -fxray-instrument for sole member functions. When the
split dwarf section is stripped, we're left with references from the
xray_instr_map to the debug section. The change now uses the function's
symbol instead of the previous section's start symbol.

We found the bug while attempting to strip the split debug sections off
an XRay-instrumented object file, which had a peculiar edge-case for
single-function classes where the single function is being lowered.
Because XRay had assocaited the instrumentation map for a function to
the debug types section instead of the function's section, the objcopy
call will fail due to the misplaced reference from the xray_instr_map
section.

Reviewers: pcc, dblaikie, echristo

Subscribers: llvm-commits, aprantl

Differential Revision: https://reviews.llvm.org/D37791

llvm-svn: 313233
2017-09-14 07:08:23 +00:00
Reid Kleckner cd7bba0264 [codeview] Fold FIXME into comment, there's nothing to do. NFC
llvm-svn: 313214
2017-09-13 23:30:01 +00:00
Reid Kleckner 89af112cf5 [codeview] VLAs and unsized arrays should use a size of zero
Previously we used a size of '1' for VLAs because we weren't sure what
MSVC did. However, MSVC does support declaring an array without a size,
for which it emits an array type with a size of zero. Clang emits the
same DI metadata for VLAs and arrays without bound, so we would describe
arrays without bound as having one element. This lead to Microsoft
debuggers only printing a single element.

Emitting a size of zero appears to cause these debuggers to search the
symbol information to find a definition of the variable with accurate
array bounds.

Fixes http://crbug.com/763580

llvm-svn: 313203
2017-09-13 21:54:20 +00:00
Adrian McCarthy d91bf3998f Mark static member functions as static in CodeViewDebug
Summary:
To improve CodeView quality for static member functions, we need to make the
static explicit.  In addition to a small change in LLVM's CodeViewDebug to
return the appropriate MethodKind, this requires a small change in Clang to
note the staticness in the debug info metadata.

Subscribers: aprantl, hiraditya

Differential Revision: https://reviews.llvm.org/D37715

llvm-svn: 313192
2017-09-13 20:53:55 +00:00
Peter Collingbourne 876da0294a Remove -generate-dwarf-pub-sections flag.
This flag is unnecessary for testing because we can get the coverage
we need by adjusting CU attributes.

Differential Revision: https://reviews.llvm.org/D37725

llvm-svn: 313079
2017-09-12 21:50:55 +00:00
Peter Collingbourne b52e23669c IR: Represent -ggnu-pubnames with a flag on the DICompileUnit.
This allows the flag to be persisted through to LTO.

Differential Revision: https://reviews.llvm.org/D37655

llvm-svn: 313078
2017-09-12 21:50:41 +00:00
Robert Lougher 51529eb0c2 Revert "[DWARF] Incorrect prologue end line record."
This reverts commit r313047 as it is causing buildbot failure (lldb inline
stepping tests).

llvm-svn: 313057
2017-09-12 18:23:15 +00:00
Robert Lougher f696a22d3c [DWARF] Incorrect prologue end line record.
A prologue-end line record is emitted with an incorrect associated address,
which causes a debugger to show the beginning of function body to be inside
the prologue.

Patch written by Carlos Alberto Enciso.

Differential Revision: https://reviews.llvm.org/D37625

llvm-svn: 313047
2017-09-12 16:35:25 +00:00
Richard Trieu c7828ebea4 Revert r312318, r312325, r312424, r312489
r312318 - Debug info for variables whose type is shrinked to bool
r312325, r312424, r312489 - Test case for r312318

Revision 312318 introduced a null dereference bug.
Details in https://bugs.llvm.org/show_bug.cgi?id=34490

llvm-svn: 312758
2017-09-07 23:20:35 +00:00
Paul Robinson bb92137080 [DWARF] Line 0 should not have a discriminator.
It's meaningless and takes up extra space in the line table.

Differential Revision: https://reviews.llvm.org/D37364

llvm-svn: 312751
2017-09-07 22:15:44 +00:00
Zachary Turner 37c747498d [CodeView] Don't output S_UDTs for nested typedefs.
S_UDT records are basically the "bridge" between the debugger's
expression evaluator and the type information. If you type
(Foo*)nullptr into the watch window, the debugger looks for an
S_UDT record named Foo. If it can find one, it displays your type.
Otherwise you get an error.

We have always understood this to mean that if you have code like
this:

  struct A {
    int X;
  };

  struct B {
    typedef A AT;
    AT Member;
  };

that you will get 3 S_UDT records. "A", "B", and "B::AT". Because
if you were to type (B::AT*)nullptr into the debugger, it would
need to find an S_UDT record named "B::AT".

But "B::AT" is actually the S_UDT record that would be generated
if B were a namespace, not a struct. So the debugger needs to be
able to distinguish this case. So what it does is:

  1. Look for an S_UDT named "B::AT". If it finds one, it knows
     that AT is in a namespace.
  2. If it doesn't find one, split at the scope resolution operator,
     and look for an S_UDT named B. If it finds one, look up the type
     for B, and then look for AT as one of its members.

With this algorithm, S_UDT records for nested typedefs are not just
unnecessary, but actually wrong!

The results of implementing this in clang are dramatic. It cuts
our /DEBUG:FASTLINK PDB sizes by more than 50%, and we go from
being ~20% larger than MSVC PDBs on average, to ~40% smaller.

It also slightly speeds up link time. We get about 10% faster
links than without this patch.

Differential Revision: https://reviews.llvm.org/D37410

llvm-svn: 312583
2017-09-05 22:06:39 +00:00
Reid Kleckner e33c94f1b0 Add llvm.codeview.annotation to implement MSVC __annotation
Summary:
This intrinsic represents a label with a list of associated metadata
strings. It is modelled as reading and writing inaccessible memory so
that it won't be removed as dead code. I think the intention is that the
annotation strings should appear at most once in the debug info, so I
marked it noduplicate. We are allowed to inline code with annotations as
long as we strip the annotation, but that can be done later.

Reviewers: majnemer

Subscribers: eraman, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D36904

llvm-svn: 312569
2017-09-05 20:14:58 +00:00
Dean Michael Berris ebc1659016 [XRay][CodeGen] Use PIC-friendly code in XRay sleds and remove synthetic references in .text
Summary:
This is a re-roll of D36615 which uses PLT relocations in the back-end
to the call to __xray_CustomEvent() when building in -fPIC and
-fxray-instrument mode.

Reviewers: pcc, djasper, bkramer

Subscribers: sdardis, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D37373

llvm-svn: 312466
2017-09-04 05:34:58 +00:00
Strahinja Petrovic 676fd0b022 Debug info for variables whose type is shrinked to bool
This patch provides such debug information for integer
variables whose type is shrinked to bool by providing 
dwarf expression which returns either constant initial 
value or other value.

Patch by Nikola Prica.

Differential Revision: https://reviews.llvm.org/D35994

llvm-svn: 312318
2017-09-01 10:05:27 +00:00
Reid Kleckner 08f5fd51cc [codeview] Generalize DIExpression parsing to handle load chains
Summary:
Hopefully this also clarifies exactly when and why we're rewriting
certiain S_LOCALs using reference types: We're using the reference type
to stand in for a zero-offset load.

Reviewers: inglorion

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37309

llvm-svn: 312247
2017-08-31 15:56:49 +00:00
Daniel Jasper c0a976d417 Revert r311525: "[XRay][CodeGen] Use PIC-friendly code in XRay sleds; remove synthetic references in .text"
Breaks builds internally. Will forward repo instructions to author.

llvm-svn: 312243
2017-08-31 15:17:17 +00:00
Bob Haarman 1a4cbbe49f [codeview] make DbgVariableLocation::extractFromMachineInstruction use Optional
Summary:
DbgVariableLocation::extractFromMachineInstruction originally
returned a boolean indicating success. This change makes it return
an Optional<DbgVariableLocation> so we cannot try to access the fields
of the struct if they aren't valid.

Reviewers: aprantl, rnk, zturner

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37279

llvm-svn: 312143
2017-08-30 17:50:21 +00:00
Bob Haarman 68e460194a [codeview] add missing break in CodeGen/AsmPrinter/DebugHandlerBase.cpp
llvm-svn: 312055
2017-08-29 22:54:31 +00:00
Bob Haarman a88bce1bce [NFC] clang-format llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
llvm-svn: 312035
2017-08-29 21:01:55 +00:00
Bob Haarman 223303c5a3 Reland r311957 [codeview] support more DW_OPs for more complete debug info
Summary:
Some variables show up in Visual Studio as "optimized out" even in -O0
-Od builds. This change fixes two issues that would cause this to
happen. The first issue is that not all DIExpressions we generate were
recognized by the CodeView writer. This has been addressed by adding
support for DW_OP_constu, DW_OP_minus, and DW_OP_plus. The second
issue is that we had no way to encode DW_OP_deref in CodeView. We get
around that by changinge the type we encode in the debug info to be
a reference to the type in the source code.

This fixes PR34261.

The reland adds two extra checks to the original: It checks if the
DbgVariableLocation is valid before checking any of its fields, and
it only emits ranges with nonzero registers.

Reviewers: aprantl, rnk, zturner

Reviewed By: rnk

Subscribers: mgorny, llvm-commits, aprantl, hiraditya

Differential Revision: https://reviews.llvm.org/D36907

llvm-svn: 312034
2017-08-29 20:59:25 +00:00
Bob Haarman 0bf0d66682 Revert "[codeview] support more DW_OPs for more complete debug info"
This reverts commit e160912f53f047bc97e572add179e08e33f4df48.

llvm-svn: 311977
2017-08-29 04:08:31 +00:00
Bob Haarman 858d098383 Revert "[codeview] don't try to emit variable locations without registers"
This reverts commit a256fbcacf448ee793d23552c46ed2971bf9eff5.

llvm-svn: 311976
2017-08-29 04:08:16 +00:00
Bob Haarman a8d0d1ab91 [codeview] don't try to emit variable locations without registers
This fixes a problem introduced 311957, where the compiler would crash
with "fatal error: error in backend: unknown codeview register".

llvm-svn: 311969
2017-08-29 01:45:54 +00:00
Bob Haarman b2a04a1513 [codeview] support more DW_OPs for more complete debug info
Summary:
Some variables show up in Visual Studio as "optimized out" even in -O0
-Od builds. This change fixes two issues that would cause this to
happen. The first issue is that not all DIExpressions we generate were
recognized by the CodeView writer. This has been addressed by adding
support for DW_OP_constu, DW_OP_minus, and DW_OP_plus. The second
issue is that we had no way to encode DW_OP_deref in CodeView. We get
around that by changinge the type we encode in the debug info to be
a reference to the type in the source code.

This fixes PR34261.

Reviewers: aprantl, rnk, zturner

Reviewed By: rnk

Subscribers: mgorny, llvm-commits, aprantl, hiraditya

Differential Revision: https://reviews.llvm.org/D36907

llvm-svn: 311957
2017-08-29 00:06:59 +00:00
Adrian Prantl 4cae108561 Fix a logic error in DwarfExpression::addMachineReg()
This fixes PR34323 and thus splitting undescribable registers into
smaller, describable sub-registers.

https://bugs.llvm.org/show_bug.cgi?id=34323

llvm-svn: 311951
2017-08-28 23:07:43 +00:00
Zachary Turner a7b041748d [CodeView] Don't output S_UDT symbols for forward decls.
S_UDT symbols are the debugger's "index" for all the structs,
typedefs, classes, and enums in a program.  If any of those
structs/classes don't have a complete declaration, or if there
is a typedef to something that doesn't have a complete definition,
then emitting the S_UDT is unhelpful because it doesn't give
the debugger enough information to do anything useful.  On the
other hand, it results in a huge size blow-up in the resulting
PDB, which is exacerbated by an order of magnitude when linking
with /DEBUG:FASTLINK.

With this patch, we drop S_UDT records for types that refer either
directly or indirectly (e.g. through a typedef, pointer, etc) to
a class/struct/union/enum without a complete definition.  This
brings us about 50% of the way towards parity with /DEBUG:FASTLINK
PDBs generated from cl-compiled object files.

Differential Revision: https://reviews.llvm.org/D37162

llvm-svn: 311904
2017-08-28 18:49:04 +00:00
NAKAMURA Takumi a1e97a77f5 Untabify.
llvm-svn: 311875
2017-08-28 06:47:47 +00:00
Dean Michael Berris 0884b73220 [XRay][CodeGen] Use PIC-friendly code in XRay sleds; remove synthetic references in .text
Summary:
This change achieves two things:

  - Redefine the Custom Event handling instrumentation points emitted by
    the compiler to not require dynamic relocation of references to the
    __xray_CustomEvent trampoline.

  - Remove the synthetic reference we emit at the end of a function that
    we used to keep auxiliary sections alive in favour of SHF_LINK_ORDER
    associated with the section where the function is defined.

To achieve the custom event handling change, we've had to introduce the
concept of sled versioning -- this will need to be supported by the
runtime to allow us to understand how to turn on/off the new version of
the custom event handling sleds. That change has to land first before we
change the way we write the sleds.

To remove the synthetic reference, we rely on a relatively new linker
feature that preserves the sections that are associated with each other.
This allows us to limit the effects on the .text section of ELF
binaries.

Because we're still using absolute references that are resolved at
runtime for the instrumentation map (and function index) maps, we mark
these sections write-able. In the future we can re-define the entries in
the map to use relative relocations instead that can be statically
determined by the linker. That change will be a bit more invasive so we
defer this for later.

Depends on D36816.

Reviewers: dblaikie, echristo, pcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36615

llvm-svn: 311525
2017-08-23 04:49:41 +00:00
Adrian Prantl 2116dd360a Filter out non-constant DIGlobalVariableExpressions reachable via the CU
They won't affect the DWARF output, but they will mess with the
sorting of the fragments. This fixes the crash reported in PR34159.

https://bugs.llvm.org/show_bug.cgi?id=34159

llvm-svn: 311217
2017-08-19 01:15:06 +00:00
Eugene Zelenko 6e07bfd0d9 [CodeGen] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 311124
2017-08-17 21:26:39 +00:00
Taewook Oh f5040b9685 Make .file directive to have basename only
Summary:
Currently LLVM puts directory along with the filename in .file directive, but this behavior doesn't match gcc. There's a no clear description about which one is right (https://sourceware.org/binutils/docs/as/File.html#File), but one document (https://sourceware.org/gdb/current/onlinedocs/stabs/ELF-Linker-Relocation.html) suggests that STT_FILE symbol in elf file is expected to have basename only, which should have a same sting file .file directive according to (https://docs.oracle.com/cd/E26502_01/html/E28388/eoiyg.html).

This also affects badly on the build system that uses hashing, as the directory info could be differnt from developer to developer even when they're working on same file.

Reviewers: pcc, mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36018

llvm-svn: 310642
2017-08-10 18:17:11 +00:00
Reid Kleckner e2e82061f9 [codeview] Emit nested enums and typedefs from classes
Previously we limited ourselves to only emitting nested classes, but we
need other kinds of types as well.

This fixes the Visual Studio STL visualizers, so that users can
visualize std::string and other objects.

llvm-svn: 310410
2017-08-08 20:30:14 +00:00
Adrian Prantl bd6d291c59 Assert that the offset of a DBG_VALUE is always 0. (NFC)
llvm-svn: 309834
2017-08-02 17:19:13 +00:00
Adrian Prantl 5577363a2c Remove the unused Offset field from MachineLocation (NFC)
rdar://problem/33580047

llvm-svn: 309831
2017-08-02 17:07:38 +00:00
Adrian Prantl 61b39b2aec Remove unused includes of MachineLocation.h (NFC)
llvm-svn: 309824
2017-08-02 15:32:18 +00:00
Adrian Prantl 2049c0d734 Remove unreachable code. (NFC)
MachineLocation::getOffset() always returns 0.

rdar://problem/33580047

llvm-svn: 309823
2017-08-02 15:22:17 +00:00
Adrian Prantl 032d2381bf Remove PrologEpilogInserter's usage of DBG_VALUE's offset field
In the last half-dozen commits to LLVM I removed code that became dead
after removing the offset parameter from llvm.dbg.value gradually
proceeding from IR towards the backend. Before I can move on to
DwarfDebug and friends there is one last side-called offset I need to
remove:  This patch modifies PrologEpilogInserter's use of the
DBG_VALUE's offset argument to use a DIExpression instead. Because the
PrologEpilogInserter runs at the Machine level I had to play a little
trick with a named llvm.dbg.mir node to get the DIExpressions to print
in MIR dumps (which print the llvm::Module followed by the
MachineFunction dump).

I also had to add rudimentary DwarfExpression support to CodeView and
as a side-effect also fixed a bug (CodeViewDebug::collectVariableInfo
was supposed to give up on variables with complex DIExpressions, but
would fail to do so for fragments, which are also modeled as
DIExpressions).

With this last holdover removed we will have only one canonical way of
representing offsets to debug locations which will simplify the code
in DwarfDebug (and future versions of CodeViewDebug once it starts
handling more complex expressions) and make it easier to reason about.

This patch is NFC-ish: All test case changes are for assembler
comments and the binary output does not change.

rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D36125

llvm-svn: 309751
2017-08-01 21:45:24 +00:00
David Blaikie c2be863681 DebugInfo: Update flag description that'd been copypasted from another
Post-commit review feedback from Paul Robinson on r309630. Thanks Paul!

llvm-svn: 309685
2017-08-01 14:50:50 +00:00
David Blaikie 038e28a5a7 DebugInfo: Put range base specifier entry functionality behind a flag
Chromium's gold build seems to have trouble with this (gold produces
errors) - not sure if it's gold that's not coping with the valid
representation, or a bug in the implementation in LLVM, etc.

llvm-svn: 309630
2017-07-31 21:48:42 +00:00
Reid Kleckner 2de471dca9 [codeview] Ignore DBG_VALUEs when choosing a BB start source loc
When the first instruction of a basic block has no location (consider a
LEA materializing the address of an alloca for a call), we want to start
the line table for the block with the first valid source location in the
block.  We need to ignore DBG_VALUE instructions during this scan to get
decent line tables.

llvm-svn: 309628
2017-07-31 21:03:08 +00:00
David Blaikie 4dd663752d DebugInfo: Fix r309526, ensure resetting base address selection entries are used
Missed the resetting base address selections when going from a base
address version to zero base address for non-base-addressed entries.

llvm-svn: 309529
2017-07-31 00:18:24 +00:00
David Blaikie 89c81a0b91 DebugInfo: Use base address selection entries in debug_ranges to reduce relocations
(from comments in the test)
Group ranges in a range list that apply to the same section and use a base
address selection entry to reduce the number of relocations to one reloc per
section per range list. DWARF5 debug_rnglist will be more efficient than this
in terms of relocations, but it's still better than one reloc per entry in a
range list.

This is an object/executable size tradeoff - shrinking objects, but growing
the linked executable. In one large binary tested, total object size (not just
debug info) shrank by 16%, entirely relocation entries. Linked executable
grew by 4%. This was with compressed debug info in the objects, uncompressed
in the linked executable. Without compression in the objects, the win would be
smaller (the growth of debug_ranges itself would be more significant).

llvm-svn: 309526
2017-07-30 22:10:00 +00:00
David Blaikie 89daf77a11 DebugInfo: Consider a CU containing only local imported entities to be 'empty'
This can come up in ThinLTO & wastes space & makes degenerate IR.

As per the added FIXME, ultimately, local imported entities should hang
off the function and that way the imported entity list on the CU can be
tested for emptiness like all the other CU lists.

(function-attached local imported entities are probably also the best
path forward for fixing how imported entities are handled both in
cross-module use (currently, while ThinLTO preserves the imported
entities, they would not get used at the imported inlined location -
only in the abstract origin that appears in the partial CU created by
the import (which isn't emitted under Fission due to cross-CU
limitations there)) and to reduce the number of points where imported
entities are emitted (they're currently emitted into every inlined
instance, concrete instance, and abstract origin - they should only go
in teh abstract origin if there is one, otherwise in the concrete
instance - but this requires lots of delayed handling and wiring up,
same as abstract variables & subprograms))

llvm-svn: 309354
2017-07-28 03:06:25 +00:00
Adrian Prantl 960e7663f3 remove redundant check
llvm-svn: 309280
2017-07-27 15:24:20 +00:00