Commit Graph

71 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
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
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
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
NAKAMURA Takumi a1e97a77f5 Untabify.
llvm-svn: 311875
2017-08-28 06:47:47 +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
Florian Hahn ffc498dfcc Align definition of DW_OP_plus with DWARF spec [3/3]
Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.
 
The way that LLVM interprets DW_OP_plus in DIExpression nodes is basically that of the DW_OP_plus_uconst operator since LLVM expects an unsigned constant operand. This unnecessarily restricts the DW_OP_plus operator, preventing it from being used to describe the evaluation of runtime values on the expression stack. These patches try to align the semantics of DW_OP_plus and DW_OP_minus with that of the DWARF definition, which pops two elements off the expression stack, performs the operation and pushes the result back on the stack.
 
This is done in three stages:
• The first patch (LLVM) adds support for DW_OP_plus_uconst.
• The second patch (Clang) contains changes all its uses from DW_OP_plus to DW_OP_plus_uconst.
• The third patch (LLVM) changes the semantics of DW_OP_plus and DW_OP_minus to be in line with its DWARF meaning. This patch includes the bitcode upgrade from legacy DIExpressions.

Patch by Sander de Smalen.

Reviewers: echristo, pcc, aprantl

Reviewed By: aprantl

Subscribers: fhahn, javed.absar, aprantl, llvm-commits

Differential Revision: https://reviews.llvm.org/D33894

llvm-svn: 305386
2017-06-14 13:14:38 +00:00
Florian Hahn c9c403c0d4 Align definition of DW_OP_plus with DWARF spec [1/3]
Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.
 
The way that LLVM interprets DW_OP_plus in DIExpression nodes is basically that of the DW_OP_plus_uconst operator since LLVM expects an unsigned constant operand. This unnecessarily restricts the DW_OP_plus operator, preventing it from being used to describe the evaluation of runtime values on the expression stack. These patches try to align the semantics of DW_OP_plus and DW_OP_minus with that of the DWARF definition, which pops two elements off the expression stack, performs the operation and pushes the result back on the stack.
 
This is done in three stages:
• The first patch (LLVM) adds support for DW_OP_plus_uconst.
• The second patch (Clang) contains changes all its uses from DW_OP_plus to DW_OP_plus_uconst.
• The third patch (LLVM) changes the semantics of DW_OP_plus and DW_OP_minus to be in line with its DWARF meaning. This patch includes the bitcode upgrade from legacy DIExpressions.

Patch by Sander de Smalen.

Reviewers: pcc, echristo, aprantl

Reviewed By: aprantl

Subscribers: fhahn, aprantl, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33892

llvm-svn: 305304
2017-06-13 16:54:44 +00:00
Zachary Turner 264b5d9e88 Move Object format code to lib/BinaryFormat.
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.

Differential Revision: https://reviews.llvm.org/D33843

llvm-svn: 304864
2017-06-07 03:48:56 +00:00
Adrian Prantl dd21502482 Fix an assertion when skipping stack values in DWARF2 mode.
The fix consists of resetting LocationKind when addMachineRegExpression fails.

rdar://problem/31803010

llvm-svn: 301351
2017-04-25 19:40:53 +00:00
Krzysztof Parzyszek 44e25f37ae Move size and alignment information of regclass to TargetRegisterInfo
1. RegisterClass::getSize() is split into two functions:
   - TargetRegisterInfo::getRegSizeInBits(const TargetRegisterClass &RC) const;
   - TargetRegisterInfo::getSpillSize(const TargetRegisterClass &RC) const;
2. RegisterClass::getAlignment() is replaced by:
   - TargetRegisterInfo::getSpillAlignment(const TargetRegisterClass &RC) const;

This will allow making those values depend on subtarget features in the
future.

Differential Revision: https://reviews.llvm.org/D31783

llvm-svn: 301221
2017-04-24 18:55:33 +00:00
Adrian Prantl 283833d022 Add a testcase for DIExpression(DW_OP_stack_value)
and relax the assertion that prohibited its emission.

This fixes the assertion failure uncovered by r301093.

llvm-svn: 301209
2017-04-24 18:11:38 +00:00
Adrian Prantl ada104888e Don't emit locations that need a DW_OP_stack_value in DWARF 2 & 3.
https://bugs.llvm.org/show_bug.cgi?id=32382

llvm-svn: 300883
2017-04-20 20:42:33 +00:00
Adrian Prantl c12cee3600 Fix bug that caused DwarfExpression to drop DW_OP_deref from FI locations
- introduced in r300522 and found via the Swift LLDB testsuite.

The fix is to set the location kind to memory whenever an FrameIndex
location is emitted.

rdar://problem/31707602

llvm-svn: 300793
2017-04-19 23:42:25 +00:00
Adrian Prantl 295c952b67 Revert "Fix bug that caused DwarfExpression to drop DW_OP_deref from FI locations"
This reverts commit r300790.

llvm-svn: 300792
2017-04-19 23:42:17 +00:00
Adrian Prantl 78ff122709 Fix bug that caused DwarfExpression to drop DW_OP_deref from FI locations
- introduced in r300522 and found via the Swift LLDB testsuite.

The fix is to set the location kind to memory whenever an FrameIndex
location is emitted.

rdar://problem/31707602

llvm-svn: 300790
2017-04-19 23:34:14 +00:00
Adrian Prantl 6825fb64e9 PR32382: Fix emitting complex DWARF expressions.
The DWARF specification knows 3 kinds of non-empty simple location
descriptions:
1. Register location descriptions
  - describe a variable in a register
  - consist of only a DW_OP_reg
2. Memory location descriptions
  - describe the address of a variable
3. Implicit location descriptions
  - describe the value of a variable
  - end with DW_OP_stack_value & friends

The existing DwarfExpression code is pretty much ignorant of these
restrictions. This used to not matter because we only emitted very
short expressions that we happened to get right by accident.  This
patch makes DwarfExpression aware of the rules defined by the DWARF
standard and now chooses the right kind of location description for
each expression being emitted.

This would have been an NFC commit (for the existing testsuite) if not
for the way that clang describes captured block variables. Based on
how the previous code in LLVM emitted locations, DW_OP_deref
operations that should have come at the end of the expression are put
at its beginning. Fixing this means changing the semantics of
DIExpression, so this patch bumps the version number of DIExpression
and implements a bitcode upgrade.

There are two major changes in this patch:

I had to fix the semantics of dbg.declare for describing function
arguments. After this patch a dbg.declare always takes the *address*
of a variable as the first argument, even if the argument is not an
alloca.

When lowering a DBG_VALUE, the decision of whether to emit a register
location description or a memory location description depends on the
MachineLocation — register machine locations may get promoted to
memory locations based on their DIExpression. (Future) optimization
passes that want to salvage implicit debug location for variables may
do so by appending a DW_OP_stack_value. For example:
  DBG_VALUE, [RBP-8]                        --> DW_OP_fbreg -8
  DBG_VALUE, RAX                            --> DW_OP_reg0 +0
  DBG_VALUE, RAX, DIExpression(DW_OP_deref) --> DW_OP_reg0 +0

All testcases that were modified were regenerated from clang. I also
added source-based testcases for each of these to the debuginfo-tests
repository over the last week to make sure that no synchronized bugs
slip in. The debuginfo-tests compile from source and run the debugger.

https://bugs.llvm.org/show_bug.cgi?id=32382
<rdar://problem/31205000>

Differential Revision: https://reviews.llvm.org/D31439

llvm-svn: 300522
2017-04-18 01:21:53 +00:00
Adrian Prantl a27198853d Rename helper functions in DwarfExpression to be less misleading (NFC)
llvm-svn: 298523
2017-03-22 17:19:55 +00:00
Adrian Prantl 0498baa4be Don't compose DWARF expressions with multiple subregisters.
If a register location can only be described by a complex expression
(i.e., multiple subregisters) it doesn't safely compose with another
complex expression. For example, it is not possible to apply a
DW_OP_deref operation to multiple DW_OP_pieces.

llvm-svn: 298472
2017-03-22 01:16:01 +00:00
Adrian Prantl 80e188d983 DwarfExpression: Defer emitting DWARF register operations
until the rest of the expression is known.

This is still an NFC refactoring in preparation of a subsequent bugfix.

This reapplies r298388 with a bugfix for non-physical frame registers.

llvm-svn: 298471
2017-03-22 01:15:57 +00:00
Adrian Prantl 4dc0324ff8 Revert 298388 and 298389 because they broke some AMDGPU tests.
llvm-svn: 298401
2017-03-21 17:14:30 +00:00
Adrian Prantl 1db6486fb1 Don't compose DWARF expressions with multiple subregisters.
If a register location can only be described by a complex expression
(i.e., multiple subregisters) it doesn't safely compose with another
complex expression. For example, it is not possible to apply a
DW_OP_deref operation to multiple DW_OP_pieces.

llvm-svn: 298389
2017-03-21 16:37:39 +00:00
Adrian Prantl dabee8e57c DwarfExpression: Defer emitting DWARF register operations
until the rest of the expression is known.

This is still an NFC refactoring in preparation of a subsequent bugfix.

llvm-svn: 298388
2017-03-21 16:37:35 +00:00
Adrian Prantl dc855221af Attempt to fix bot failure on Windows.
Looks like this expression was accidentally using 32-bit arithmetic.

llvm-svn: 297969
2017-03-16 18:06:04 +00:00
Adrian Prantl a63b8e8227 Rename methods in DwarfExpression to adhere to the LLVM coding guidelines.
NFC.

llvm-svn: 297966
2017-03-16 17:42:45 +00:00
Adrian Prantl 981f03e6a2 PR32288: More efficient encoding for DWARF expr subregister access.
Citing http://bugs.llvm.org/show_bug.cgi?id=32288

  The DWARF generated by LLVM includes this location:

  0x55 0x93 0x04 DW_OP_reg5 DW_OP_piece(4) When GCC's DWARF is simply
  0x55 (DW_OP_reg5) without the DW_OP_piece. I believe it's reasonable
  to assume the DWARF consumer knows which part of a register
  logically holds the value (low bytes, high bytes, how many bytes,
  etc) for a primitive value like an integer.

This patch gets rid of the redundant DW_OP_piece when a subregister is
at offset 0. It also adds previously missing subregister masking when
a subregister is followed by another operation.

(This reapplies r297960 with two additional testcase updates).

rdar://problem/31069390
https://reviews.llvm.org/D31010

llvm-svn: 297965
2017-03-16 17:14:56 +00:00
Adrian Prantl c5b3351750 Revert "PR32288: More efficient encoding for DWARF expr subregister access."
This reverts commit 2bf453116889a576956892ea9683db4fcd96e30e while investigating buildbot breakage.

llvm-svn: 297962
2017-03-16 16:38:22 +00:00
Adrian Prantl 8508e87998 PR32288: More efficient encoding for DWARF expr subregister access.
Citing http://bugs.llvm.org/show_bug.cgi?id=32288

  The DWARF generated by LLVM includes this location:

  0x55 0x93 0x04 DW_OP_reg5 DW_OP_piece(4) When GCC's DWARF is simply
  0x55 (DW_OP_reg5) without the DW_OP_piece. I believe it's reasonable
  to assume the DWARF consumer knows which part of a register
  logically holds the value (low bytes, high bytes, how many bytes,
  etc) for a primitive value like an integer.

This patch gets rid of the redundant DW_OP_piece when a subregister is
at offset 0. It also adds previously missing subregister masking when
a subregister is followed by another operation.

rdar://problem/31069390
https://reviews.llvm.org/D31010

llvm-svn: 297960
2017-03-16 16:34:14 +00:00
Konstantin Zhuravlyov f9b41cd3d8 [DebugInfo] Make legal and emit DW_OP_swap and DW_OP_xderef
Differential Revision: https://reviews.llvm.org/D29672

llvm-svn: 297247
2017-03-08 00:28:57 +00:00
Tim Northover 5d27063eb4 DebugInfo: remove unused parameter from function. NFC.
I think it's a hold-over from some previous iteration, but it's never
set to true in LLVM as it exists now.

llvm-svn: 293086
2017-01-25 20:58:07 +00:00
Adrian Prantl 5542da4bbc Fix an assertion in DwarfExpression when emitting fragments in vector registers
When DwarfExpression is emitting a fragment that is located in a
register and that fragment is smaller than the register, and the
register must be composed from sub-registers (are you still with me?)
the last DW_OP_piece operation must not be larger than the size of the
fragment itself, since the last piece of the fragment could be smaller
than the last subregister that is being emitted.

rdar://problem/29779065

llvm-svn: 290324
2016-12-22 06:10:41 +00:00
Adrian Prantl 49797ca6be Refactor the DIExpression fragment query interface (NFC)
... so it becomes available to DIExpressionCursor.

llvm-svn: 290322
2016-12-22 05:27:12 +00:00
Adrian Prantl 8fafb8d378 Fix LLVM's use of DW_OP_bit_piece in DWARF expressions.
LLVM's use of DW_OP_bit_piece is incorrect and a based on a
misunderstanding of the wording in the DWARF specification. The offset
argument of DW_OP_bit_piece refers to the offset into the location
that is on the top of the DWARF expression stack, and not an offset
into the source variable. This has since also been clarified in the
DWARF specification.

This patch fixes all uses of DW_OP_bit_piece to emit the correct
offset and simplifies the DwarfExpression class to semi-automaticaly
emit empty DW_OP_pieces to adjust the offset of the source variable,
thus simplifying the code using DwarfExpression.

While this is an incompatible bugfix, in practice I don't expect this
to be much of a problem since LLVM's old interpretation and the
correct interpretation of DW_OP_bit_piece differ only when there are
gaps in the fragmented locations of the described variables or if
individual fragments are smaller than a byte. LLDB at least won't
interpret locations with gaps in them because is has no way to present
undefined bits in a variable, and there is a high probability that an
old-form expression will be malformed when interpreted correctly,
because the DW_OP_bit_piece offset will be outside of the location at
the top of the stack.

As a nice side-effect, this patch enables us to use a more efficient
encoding for subregisters: In order to express a sub-register at a
non-zero offset we now use a DW_OP_bit_piece instead of shifting the
value into place manually.

This patch also adds missing test coverage for code paths that weren't
exercised before.

<rdar://problem/29335809>
Differential Revision: https://reviews.llvm.org/D27550

llvm-svn: 289266
2016-12-09 20:43:40 +00:00
Adrian Prantl 941fa7588b [DIExpression] Introduce a dedicated DW_OP_LLVM_fragment operation
so we can stop using DW_OP_bit_piece with the wrong semantics.

The entire back story can be found here:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20161114/405934.html

The gist is that in LLVM we've been misinterpreting DW_OP_bit_piece's
offset field to mean the offset into the source variable rather than
the offset into the location at the top the DWARF expression stack. In
order to be able to fix this in a subsequent patch, this patch
introduces a dedicated DW_OP_LLVM_fragment operation with the
semantics that we used to apply to DW_OP_bit_piece, which is what we
actually need while inside of LLVM. This patch is complete with a
bitcode upgrade for expressions using the old format. It does not yet
fix the DWARF backend to use DW_OP_bit_piece correctly.

Implementation note: We discussed several options for implementing
this, including reserving a dedicated field in DIExpression for the
fragment size and offset, but using an custom operator at the end of
the expression works just fine and is more efficient because we then
only pay for it when we need it.

Differential Revision: https://reviews.llvm.org/D27361
rdar://problem/29335809

llvm-svn: 288683
2016-12-05 18:04:47 +00:00
Adrian Prantl 54286bda2c Simplify control flow in the the DWARF expression compiler
by refactoring common code into a DwarfExpressionCursor wrapper.

llvm-svn: 285827
2016-11-02 16:12:20 +00:00
Peter Collingbourne d4135bbc30 DebugInfo: New metadata representation for global variables.
This patch reverses the edge from DIGlobalVariable to GlobalVariable.
This will allow us to more easily preserve debug info metadata when
manipulating global variables.

Fixes PR30362. A program for upgrading test cases is attached to that
bug.

Differential Revision: http://reviews.llvm.org/D20147

llvm-svn: 281284
2016-09-13 01:12:59 +00:00
Adrian Prantl 29ce701a06 Fix the type signature of DwarfExpression::Add.*Constant to support values >32 bits.
This fixes an embarrassing bug when emitting .debug_loc entries for 64-bit+ constants,
which were previously silently truncated to 32 bits.

<rdar://problem/26843232>

llvm-svn: 273736
2016-06-24 21:35:09 +00:00
Benjamin Kramer c321e53402 Apply most suggestions of clang-tidy's performance-unnecessary-value-param
Avoids unnecessary copies. All changes audited & pass tests with asan.
No functional change intended.

llvm-svn: 272190
2016-06-08 19:09:22 +00:00
Peter Collingbourne 96c9ae6a20 CodeGen: Do not require a MachineFunction just to create a DIEDwarfExpression.
We are about to start using DIEDwarfExpression to create global variable
DIEs, which happens before we generate code for functions.

Differential Revision: http://reviews.llvm.org/D20412

llvm-svn: 270257
2016-05-20 19:35:17 +00:00
Adrian Prantl 3e9c88753b DwarfDebug: Support floating point constants in location lists.
This patch closes a gap in the DWARF backend that caused LLVM to drop
debug info for floating point variables that were constant for part of
their scope. Floating point constants are emitted as one or more
DW_OP_constu joined via DW_OP_piece.

This fixes a regression caught by the LLDB testsuite that I introduced
in r262247 when we stopped blindly expanding the range of singular
DBG_VALUEs to span the entire scope and started to emit location lists
with accurate ranges instead.

Also deletes a now-impossible testcase (debug-loc-empty-entries).

<rdar://problem/25448338>

llvm-svn: 265760
2016-04-08 00:38:37 +00:00
Evgeniy Stepanov f608111d1b Fix debug info with SafeStack.
llvm-svn: 248933
2015-09-30 19:55:43 +00:00
David Blaikie 0ebe35b278 Revert "[DWARF] Fix a few corner cases in expression emission"
This reverts commit r239380 due to apparently GDB regressions:
http://lab.llvm.org:8011/builders/clang-x86_64-ubuntu-gdb-75/builds/22562

llvm-svn: 239420
2015-06-09 18:01:51 +00:00
Keno Fischer e34147ce2f [DWARF] Fix a few corner cases in expression emission
Summary: I noticed an object file with `DW_OP_reg4 DW_OP_breg4 0` as a DWARF expression,
which I traced to a missing break (and `++I`) in this code snippet.
While I was at it, I also added support for a few other corner cases
along the same lines that I could think of.

Test Plan: Hand-crafted test case to exercises these cases is included.

Reviewers: echristo, dblaikie, aprantl

Reviewed By: aprantl

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10302

llvm-svn: 239380
2015-06-09 01:53:59 +00:00
Duncan P. N. Exon Smith a9308c49ef IR: Give 'DI' prefix to debug info metadata
Finish off PR23080 by renaming the debug info IR constructs from `MD*`
to `DI*`.  The last of the `DIDescriptor` classes were deleted in
r235356, and the last of the related typedefs removed in r235413, so
this has all baked for about a week.

Note: If you have out-of-tree code (like a frontend), I recommend that
you get everything compiling and tests passing with the *previous*
commit before updating to this one.  It'll be easier to keep track of
what code is using the `DIDescriptor` hierarchy and what you've already
updated, and I think you're extremely unlikely to insert bugs.  YMMV of
course.

Back to *this* commit: I did this using the rename-md-di-nodes.sh
upgrade script I've attached to PR23080 (both code and testcases) and
filtered through clang-format-diff.py.  I edited the tests for
test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns
were off-by-three.  It should work on your out-of-tree testcases (and
code, if you've followed the advice in the previous paragraph).

Some of the tests are in badly named files now (e.g.,
test/Assembler/invalid-mdcompositetype-missing-tag.ll should be
'dicompositetype'); I'll come back and move the files in a follow-up
commit.

llvm-svn: 236120
2015-04-29 16:38:44 +00:00
Duncan P. N. Exon Smith 60635e39b6 DebugInfo: Drop rest of DIDescriptor subclasses
Delete the remaining subclasses of (the already deleted) `DIDescriptor`.
Part of PR23080.

llvm-svn: 235404
2015-04-21 18:44:06 +00:00
Duncan P. N. Exon Smith 76c9184434 DebugInfo: Remove special iterators from DIExpression
Remove special iterators from `DIExpression` in favour of same in
`MDExpression`.  There should be no functionality change here.

Note that the APIs are slightly different: `getArg(unsigned)` counts
from 0, not 1, in the `MDExpression` version of the iterator.

llvm-svn: 234285
2015-04-07 03:45:57 +00:00
Adrian Prantl 0f61579602 Fix DwarfExpression::AddMachineRegExpression so it doesn't read past the
end of an expression that ends with DW_OP_plus.
Caught by the ASAN build bots.

llvm-svn: 231260
2015-03-04 17:39:33 +00:00
Adrian Prantl b283815a30 Fix PR22762. When emitting a DWARF expression check whether this is the
frame register before checking if there is a DWARF register number for it.

Thanks to H.J. Lu for diagnosing this and providing the testcase!

llvm-svn: 231121
2015-03-03 20:12:52 +00:00
Adrian Prantl 92da14b244 Refactor DebugLocDWARFExpression so it doesn't require access to the
TargetRegisterInfo. DebugLocEntry now holds a buffer with the raw bytes
of the pre-calculated DWARF expression.

Ought to be NFC, but it does slightly alter the output format of the
textual assembly.

This reapplies 230930 without the assertion in DebugLocEntry::finalize()
because not all Machine registers can be lowered into DWARF register
numbers and floating point constants cannot be expressed.

llvm-svn: 231023
2015-03-02 22:02:33 +00:00
Adrian Prantl 2185aa179d Revert "Refactor DebugLocDWARFExpression so it doesn't require access to the"
This reverts commit 230975 to investigate buildbot breakage.

llvm-svn: 231004
2015-03-02 20:01:54 +00:00