In debug frame information, some fields, e.g., Length in CIE/FDE and
Offset in FDE are attributes to describe the structure of CIE/FDE. They
are not related to the relaxed code. However, these attributes are
symbol differences. So, in current design, these attributes will be
filled as zero and LLVM generates relocations for them.
We only need to generate relocations for symbols in executable sections.
So, if the symbols are not located in executable sections, we still
evaluate their values under relaxation.
Differential Revision: https://reviews.llvm.org/D61584
llvm-svn: 366531
It is necessary to generate fixups in .debug_frame or .eh_frame as
relaxation is enabled due to the address delta may be changed after
relaxation.
There is an opcode with 6-bits data in debug frame encoding. So, we
also need 6-bits fixup types.
Differential Revision: https://reviews.llvm.org/D58335
llvm-svn: 366524
It is necessary to generate fixups in .debug_frame or .eh_frame as
relaxation is enabled due to the address delta may be changed after
relaxation.
There is an opcode with 6-bits data in debug frame encoding. So, we
also need 6-bits fixup types.
Differential Revision: https://reviews.llvm.org/D58335
llvm-svn: 366442
Windows sees DW_AT_decl_file (".\dwarf-riscv-relocs.c") while Linux sees
DW_AT_decl_file ("./dwarf-riscv-relocs.c").
This fixes a failure introduced in rL366402.
llvm-svn: 366410
When code relaxation is enabled many RISC-V fixups are not resolved but
instead relocations are emitted. This happens even for DWARF debug
sections. Therefore, to properly support the parsing of DWARF debug info
we need to be able to resolve RISC-V relocations. This patch adds:
* Support for RISC-V relocations in RelocationResolver
* DWARF support for two relocations per object file offset
* DWARF changes to support relocations in more DIE fields
The two relocations per offset change is needed because some RISC-V
relocations (used for label differences) come in pairs.
Relocations can also be emitted for DWARF fields where relocations were
not yet evaluated. Adding relocation support for some of these fields is
essencial. On the other hand, LLVM currently emits RISC-V relocations
for fixups that could be safely evaluated, since they can never be
affected by code relaxations. This patch also adds relocation support
for the fields affected by those extraneous relocations (the DWARF unit
entry Length, and the DWARF debug line entry TotalLength and
PrologueLength), for testing purposes.
Differential Revision: https://reviews.llvm.org/D62062
Patch by Luís Marques.
llvm-svn: 366402
D64033 <https://reviews.llvm.org/D64033> added DW_AT_call_column for
inline sites. However, that change wasn't aware of "-gno-column-info".
To avoid adding column info when "-gno-column-info" is used, now
DW_AT_call_column is only added when we have non-zero column (when
"-gno-column-info" is used, column will be zero).
Patch by Wenlei He!
Differential Revision: https://reviews.llvm.org/D64784
llvm-svn: 366264
The column field is missing for all inline sites, currently it's always
zero. This changes populates DW_AT_call_column field for inline sites.
Test case modified to cover this change.
Patch by: Wenlei He
Differential revision: https://reviews.llvm.org/D64033
llvm-svn: 365945
- The test had extension .yaml, which lit doesn't execute in this
directory. Rename to .test to make it run, and move the yaml bits
into a dedicated file, like with all other tests in this dir.
- llvm-pdbdump got renamed to llvm-pdbutil long ago, update test.
- -dbi-module-info got renamed in r305032, update test for this too.
llvm-svn: 365514
Dump the DWARF information about call sites and call site parameters into
debug info sections.
The patch also provides an interface for the interpretation of instructions
that could load values of a call site parameters in order to generate DWARF
about the call site parameters.
([13/13] Introduce the debug entry values.)
Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>
Differential Revision: https://reviews.llvm.org/D60716
llvm-svn: 365467
Emit replacements for clobbered parameters location if the parameter
has unmodified value throughout the funciton. This is basic scenario
where we can use the debug entry values.
([12/13] Introduce the debug entry values.)
Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>
Differential Revision: https://reviews.llvm.org/D58042
llvm-svn: 365444
This patch addresses PR41675, where a stack-pointer variable is dereferenced
too many times by its location expression, presenting a value on the stack as
the pointer to the stack.
The difference between a stack *pointer* DBG_VALUE and one that refers to a
value on the stack, is currently the indirect flag. However the DWARF backend
will also try to guess whether something is a memory location or not, based
on whether there is any computation in the location expression. By simply
prepending the stack offset to existing expressions, we can accidentally
convert a register location into a memory location, which introduces a
suprise (and unintended) dereference.
The solution is to add DW_OP_stack_value whenever we add a DIExpression
computation to a stack *pointer*. It's an implicit location computed on the
expression stack, thus needs to be flagged as a stack_value.
For the edge case where the offset is zero and the location could be a register
location, DIExpression::prepend will still generate opcodes, and thus
DW_OP_stack_value must still be added.
Differential Revision: https://reviews.llvm.org/D63429
llvm-svn: 364736
Emit replacements for clobbered parameters location if the parameter
has unmodified value throughout the funciton. This is basic scenario
where we can use the debug entry values.
([12/13] Introduce the debug entry values.)
Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>
Differential Revision: https://reviews.llvm.org/D58042
llvm-svn: 364553
Once MIR code leaves SSA form and the liveness of a vreg is considered,
DBG_VALUE insts are able to refer to non-live vregs, because their
debug-uses do not contribute to liveness. This non-liveness becomes
problematic for optimizations like register coalescing, as they can't
``see'' the debug uses in the liveness analyses.
As a result registers get coalesced regardless of debug uses, and that can
lead to invalid variable locations containing unexpected values. In the
added test case, the first vreg operand of ADD32rr is merged with various
copies of the vreg (great for performance), but a DBG_VALUE of the
unmodified operand is blindly updated to the modified operand. This changes
what value the variable will appear to have in a debugger.
Fix this by changing any DBG_VALUE whose operand will be resurrected by
register coalescing to be a $noreg DBG_VALUE, i.e. give the variable no
location. This is an overapproximation as some coalesced locations are
safe (others are not) -- an extra domination analysis would be required to
work out which, and it would be better if we just don't generate non-live
DBG_VALUEs.
This fixes PR40010.
Differential Revision: https://reviews.llvm.org/D56151
llvm-svn: 364515
Summary:
Implements direct and indirect tail calls enabled by the 'tail-call'
feature in both DAG ISel and FastISel. Updates existing call tests and
adds new tests including a binary encoding test.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62877
llvm-svn: 364445
The test only checks the existence of the `Types CU list` line.
Unfortunately I can't make a better test because
{gcc,clang} -fuse-ld={lld,gold} --gdb-index do not give me a non-empty types CU list.
Reviewed By: ikudrin
Differential Revision: https://reviews.llvm.org/D63537
llvm-svn: 363800
Summary:
Bug: https://bugs.llvm.org/show_bug.cgi?id=39024
The bug reports that a vectorized loop is stepped through 4 times and each step through the loop seemed to show a different path. I found two problems here:
A) An incorrect line number on a preheader block (for.body.preheader) instruction causes a step into the loop before it begins.
B) Instructions in the middle block have different line numbers which give the impression of another iteration.
In this patch I give all of the middle block instructions the line number of the scalar loop latch terminator branch. This seems to provide the smoothest debugging experience because the vectorized loops will always end on this line before dropping into the scalar loop. To solve problem A I have altered llvm::SplitBlockPredecessors to accommodate loop header blocks.
I have set up a separate review D61933 for a fix which is required for this patch.
Reviewers: samsonov, vsk, aprantl, probinson, anemet, hfinkel, jmorse
Reviewed By: hfinkel, jmorse
Subscribers: jmorse, javed.absar, eraman, kcc, bjope, jmellorcrummey, hfinkel, gbedwell, hiraditya, zzheng, llvm-commits
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D60831
> llvm-svn: 363046
llvm-svn: 363786
This allows targets to make more decisions about reserved registers
after isel. For example, now it should be certain there are calls or
stack objects in the frame or not, which could have been introduced by
legalization.
Patch by Matthias Braun
llvm-svn: 363757
This patch changes MIR stack-id from an integer to an enum,
and adds printing/parsing support for this in MIR files. The default
stack-id '0' is now renamed to 'default'.
This should make MIR tests that have stack objects with different stack-ids
more descriptive. It also clarifies code operating on StackID.
Reviewers: arsenm, thegameg, qcolombet
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D60137
llvm-svn: 363533
Current findBestLoopTop can find and move one kind of block to top, a latch block has one successor. Another common case is:
* a latch block
* it has two successors, one is loop header, another is exit
* it has more than one predecessors
If it is below one of its predecessors P, only P can fall through to it, all other predecessors need a jump to it, and another conditional jump to loop header. If it is moved before loop header, all its predecessors jump to it, then fall through to loop header. So all its predecessors except P can reduce one taken branch.
Differential Revision: https://reviews.llvm.org/D43256
llvm-svn: 363471
This is consistent with GCC's behavior (which is the defacto standard
for pubnames). Though I find the presence of enumerators from enum
classes to be a bit confusing, possibly a bug on GCC's end (since they
can't be named unqualified, unlike the other names - and names nested in
classes don't go in pubnames, for instance - presumably because one must
name the class first & that's enough to limit the scope of the search)
llvm-svn: 363349
Summary:
Before it was using the fully qualified name only for static data members.
Now it does for all variable names to match MSVC.
Reviewers: rnk
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63012
llvm-svn: 363335
Constants, including G_GLOBAL_VALUE, are all emitted into the entry block which
lets us use the vreg def assuming it dominates all other users. However, it can
cause jumpy debug behaviour since the DebugLoc attached to these MIs are from
a user instruction that could be in a different block.
Fixes PR40887.
Differential Revision: https://reviews.llvm.org/D63286
llvm-svn: 363331
This patch makes the LiveDebugValues pass consider fragments when propagating
DBG_VALUE insts between blocks, fixing PR41979. Fragment info for a variable
location is added to the open-ranges key, which allows distinct fragments to be
tracked separately. To handle overlapping fragments things become slightly
funkier. To avoid excessive searching for overlaps in the data-flow part of
LiveDebugValues, this patch:
* Pre-computes pairings of fragments that overlap, for each DILocalVariable
* During data-flow, whenever something happens that causes an open range to
be terminated (via erase), any fragments pre-determined to overlap are
also terminated.
The effect of which is that when encountering a DBG_VALUE fragment that
overlaps others, the overlapped fragments do not get propagated to other
blocks. We still rely on later location-list building to correctly handle
overlapping fragments within blocks.
It's unclear whether a mixture of DBG_VALUEs with and without fragmented
expressions are legitimate. To avoid suprises, this patch interprets a
DBG_VALUE with no fragment as overlapping any DBG_VALUE _with_ a fragment.
Differential Revision: https://reviews.llvm.org/D62904
llvm-svn: 363256
We aim to ignore changes in variable locations during the prologue and
epilogue of functions, to avoid using space documenting location changes
that aren't visible. However in D61940 / r362951 this got ripped out as
the previous implementation was unsound.
Instead, use the FrameDestroy flag to identify when we're in the epilogue
of a function, and ignore variable location changes accordingly. This fits
in with existing code that examines the FrameSetup flag.
Some variable locations get shuffled in modified tests as they now cover
greater ranges, which is what would be expected. Some additional
single-location variables are generated too. Two tests are un-xfailed,
they were only xfailed due to r362951 deleting functionality they depended
on.
Apparently some out-of-tree backends don't accurately maintain FrameDestroy
flags -- if you're an out-of-tree maintainer and see changes in variable
locations disappear due to a faulty FrameDestroy flag, it's safe to back
this change out. The impact is just slightly more debug info than necessary.
Differential Revision: https://reviews.llvm.org/D62314
llvm-svn: 363245
Summary:
Bug: https://bugs.llvm.org/show_bug.cgi?id=39024
The bug reports that a vectorized loop is stepped through 4 times and each step through the loop seemed to show a different path. I found two problems here:
A) An incorrect line number on a preheader block (for.body.preheader) instruction causes a step into the loop before it begins.
B) Instructions in the middle block have different line numbers which give the impression of another iteration.
In this patch I give all of the middle block instructions the line number of the scalar loop latch terminator branch. This seems to provide the smoothest debugging experience because the vectorized loops will always end on this line before dropping into the scalar loop. To solve problem A I have altered llvm::SplitBlockPredecessors to accommodate loop header blocks.
I have set up a separate review D61933 for a fix which is required for this patch.
Reviewers: samsonov, vsk, aprantl, probinson, anemet, hfinkel, jmorse
Reviewed By: hfinkel, jmorse
Subscribers: jmorse, javed.absar, eraman, kcc, bjope, jmellorcrummey, hfinkel, gbedwell, hiraditya, zzheng, llvm-commits
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D60831
llvm-svn: 363046
This behavior was added in r130928 for both FastISel and SD, and then
disabled in r131156 for FastISel.
This re-enables it for FastISel with the corresponding fix.
This is triggered only when FastISel can't lower the arguments and falls
back to SelectionDAG for it.
FastISel contains a map of "register fixups" where at the end of the
selection phase it replaces all uses of a register with another
register that FastISel sometimes pre-assigned. Code at the end of
SelectionDAGISel::runOnMachineFunction is doing the replacement at the
very end of the function, while other pieces that come in before that
look through the MachineFunction and assume everything is done. In this
case, the real issue is that the code emitting COPY instructions for the
liveins (physreg to vreg) (EmitLiveInCopies) is checking if the vreg
assigned to the physreg is used, and if it's not, it will skip the COPY.
If a register wasn't replaced with its assigned fixup yet, the copy will
be skipped and we'll end up with uses of undefined registers.
This fix moves the replacement of registers before the emission of
copies for the live-ins.
The initial motivation for this fix is to enable tail calls for
swiftself functions, which were blocked because we couldn't prove that
the swiftself argument (which is callee-save) comes from a function
argument (live-in), because there was an extra copy (vreg to vreg).
A few tests are affected by this:
* llvm/test/CodeGen/AArch64/swifterror.ll: we used to spill x21
(callee-save) but never reload it because it's attached to the return.
We now don't even spill it anymore.
* llvm/test/CodeGen/*/swiftself.ll: we tail-call now.
* llvm/test/CodeGen/AMDGPU/mubuf-legalize-operands.ll: I believe this
test was not really testing the right thing, but it worked because the
same registers were re-used.
* llvm/test/CodeGen/ARM/cmpxchg-O0.ll: regalloc changes
* llvm/test/CodeGen/ARM/swifterror.ll: get rid of a copy
* llvm/test/CodeGen/Mips/*: get rid of spills and copies
* llvm/test/CodeGen/SystemZ/swift-return.ll: smaller stack
* llvm/test/CodeGen/X86/atomic-unordered.ll: smaller stack
* llvm/test/CodeGen/X86/swifterror.ll: same as AArch64
* llvm/test/DebugInfo/X86/dbg-declare-arg.ll: stack size changed
Differential Revision: https://reviews.llvm.org/D62361
llvm-svn: 362963
This commit reapplies r359426 (which was reverted in r360301 due to
performance problems) and rolls in D61940 to address the performance problem.
I've combined the two to avoid creating a span of slow-performance, and to
ease reverting if more problems crop up.
The summary of D61940: This patch removes the "ChangingRegs" facility in
DbgEntityHistoryCalculator, as its overapproximate nature can produce incorrect
variable locations. An unchanging register doesn't mean a variable doesn't
change its location.
The patch kills off everything that calculates the ChangingRegs vector.
Previously ChangingRegs spotted epilogues and marked registers as unchanging if
they weren't modified outside the epilogue, increasing the chance that we can
emit a single-location variable record. Without this feature,
debug-loc-offset.mir and pr19307.mir become temporarily XFAIL. They'll be
re-enabled by D62314, using the FrameDestroy flag to identify epilogues, I've
split this into two steps as FrameDestroy isn't necessarily supported by all
backends.
The logic for terminating variable locations at the end of a basic block now
becomes much more enjoyably simple: we just terminate them all.
Other test changes: inlined-argument.ll becomes XFAIL, but for a longer term.
The current algorithm for detecting that a variable has a single-location
doesn't work in this scenario (inlined function in multiple blocks), only other
bugs were making this test work. fission-ranges.ll gets slightly refreshed too,
as the location of "p" is now correctly determined to be a single location.
Differential Revision: https://reviews.llvm.org/D61940
llvm-svn: 362951
Variable's stack location can stretch longer than it should. If a
variable is placed at the stack in a some nested basic block its range
can be calculated to be up to the next occurrence of the variable's
DBG_VALUE, or up to the end of the function, thus covering a basic
blocks that should not be included in the variable’s location range.
This happens because the DbgEntityHistoryCalculator ends register
locations at the end of a basic block only if the variable’s location
register has been changed throughout the function, which is not the
case for the register used to reference stack objects.
This patch also tries to produce a single value location if the location
list builder managed to merge all the locations into one.
Reviewers: aprantl, dstenb, jmorse
Reviewed By: aprantl, dstenb, jmorse
Subscribers: djtodoro, ivanbaev, asowda
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D61600
llvm-svn: 362923
Incorrect Debug Variable Range was calculated while "COMPUTING LIVE DEBUG VARIABLES" stage.
Range for Debug Variable("i") computed according to current state of instructions
inside of basic block. But Register Allocator creates new instructions which were not taken
into account when Live Debug Variables computed. In the result DBG_VALUE instruction for
the "i" variable was put after these newly inserted instructions. This is incorrect.
Debug Value for the loop counter should be inserted before any loop instruction.
Differential Revision: https://reviews.llvm.org/D62650
llvm-svn: 362750
When LiveDebugValues deduces new variable's location from spill, restore or
register copy instruction it should close old variable's location. Otherwise
we can have multiple block output locations for same variable. That could lead
to inserting two DBG_VALUEs for same variable to the beginning of the successor
block which results to ignoring of first DBG_VALUE.
Reviewers: aprantl, jmorse, wolfgangp, dstenb
Reviewed By: aprantl
Subscribers: probinson, asowda, ivanbaev, petarj, djtodoro
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D62196
llvm-svn: 362373
ARM64 CodeView test was incorrectly put under test/DebugInfo/COFF folder which
runs for all all architectures. This fix moves it to a subfolder AArch64 with
lit.local.cfg which specify it supports AArch64 only.
llvm-svn: 362283
CodeView has its own register map which is defined in cvconst.h. Missing this
mapping before saving register to CodeView causes debugger to show incorrect
value for all register based variables, like variables in register and local
variables addressed by register (stack pointer + offset).
This change added mapping between LLVM register and CodeView register so the
correct register number will be stored to CodeView/PDB, it aso fixed the
mapping from CodeView register number to register name based on current
CPUType but print PDB to yaml still assumes X86 CPU and needs to be fixed.
Differential Revision: https://reviews.llvm.org/D62608
llvm-svn: 362280
Summary:
Keeps track of the enums that were used by saving them as DIGlobalVariables,
since CodeView emits debug info for global constants.
Reviewers: rnk
Subscribers: aprantl, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D62635
llvm-svn: 362166
Summary:
Add static data members to IR debug info's list of global variables
so that they are emitted as S_CONSTANT records.
Related to https://bugs.llvm.org/show_bug.cgi?id=41615.
Reviewers: rnk
Subscribers: aprantl, cfe-commits, llvm-commits, thakis
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D62167
llvm-svn: 362038
Summary:
When DwarfDebug::buildLocationList() encountered an undef debug value,
it would truncate all open values, regardless if they were overlapping or
not. This patch fixes so that it only does that for overlapping fragments.
This change unearthed a bug that I had introduced in D57511,
which I have fixed in this patch. The code in DebugHandlerBase that
changes labels for parameter debug values could break DwarfDebug's
assumption that the labels for the entries in the debug value history
are monotonically increasing. Before this patch, that bug could result
in location list entries whose ending address was lower than the
beginning address, and with the changes for undef debug values that this
patch introduces it could trigger an assertion, due to attempting to
emit location list entries with empty ranges. A reproducer for the bug
is added in param-reg-const-mix.mir.
Reviewers: aprantl, jmorse, probinson
Reviewed By: aprantl
Subscribers: javed.absar, llvm-commits
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D62379
llvm-svn: 361820
This lead to errors when dumping binaries with v4 and v5 units linked
together (but could've also errored on v5 units that did/didn't use
str_offsets).
Also improves error handling and messages around invalid str_offsets
contributions.
llvm-svn: 361683
This test case was incorrect because it mixed DWARF32 and DWARF64 for a
single unit (DWARF32 unit referencing a DWARF64 str_offsets section). So
fix enough of the unit parsing for DWARF64 and make the test valid.
(not sure if anyone needs DWARF64 support though - support in
libDebugInfoDWARF has been added piecemeal and LLVM doesn't produce it
at all)
llvm-svn: 361582
This reverts commit rr360902. It caused an assertion failure in
lib/IR/DebugInfoMetadata.cpp: Assertion `(OffsetInBits + SizeInBits <=
FragmentSizeInBits) && "new fragment outside of original fragment"'
failed.
PR41931.
llvm-svn: 361246
This option provides only the base filename, not a full relative path.
Part of the fix for PR41839.
Differential Revision: https://reviews.llvm.org/D62071
llvm-svn: 361245
Summary:
This emits S_CONSTANT records for global variables.
Currently this emits records for the global variables already being tracked in the
LLVM IR metadata, which are just constant global variables; we'll also want S_CONSTANTs
for static data members and enums.
Related to https://bugs.llvm.org/show_bug.cgi?id=41615
Reviewers: rnk
Subscribers: aprantl, hiraditya, llvm-commits, thakis
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61926
llvm-svn: 360948
Fixes issue: https://bugs.llvm.org/show_bug.cgi?id=40645
Previously, LLVM had no functional way of performing casts inside of a
DIExpression(), which made salvaging cast instructions other than Noop casts
impossible. With the recent addition of DW_OP_LLVM_convert this salvaging is
now possible, and so can be used to fix the attached bug as well as any cases
where SExt instruction results are lost in the debugging metadata. This patch
introduces this fix by expanding the salvage debug info method to cover these
cases using the new operator.
Differential revision: https://reviews.llvm.org/D61184
llvm-svn: 360902
Trace through multiple COPYs when looking for a physreg source. Add
hinting for vregs that will be copied into physregs (we only hinted
for vregs getting copied to a physreg previously). Give hinted a
register a bonus when deciding which value to spill. This is part of
my rewrite regallocfast series. In fact this one doesn't even have an
effect unless you also flip the allocation to happen from back to
front of a basic block. Nonetheless it helps to split this up to ease
review of D52010
Patch by Matthias Braun
llvm-svn: 360887
Fixes issue: https://bugs.llvm.org/show_bug.cgi?id=40645
Previously, LLVM had no functional way of performing casts inside of a
DIExpression(), which made salvaging cast instructions other than Noop
casts impossible. With the recent addition of DW_OP_LLVM_convert this
salvaging is now possible, and so can be used to fix the attached bug as
well as any cases where SExt instruction results are lost in the
debugging metadata. This patch introduces this fix by expanding the
salvage debug info method to cover these cases using the new operator.
Differential revision: https://reviews.llvm.org/D61184
llvm-svn: 360772
The 3-field form was introduced by D3499 in 2014 and the legacy 2-field
form was planned to be removed in LLVM 4.0
For the textual format, this patch migrates the existing 2-field form to
use the 3-field form and deletes the compatibility code.
test/Verifier/global-ctors-2.ll checks we have a friendly error message.
For bitcode, lib/IR/AutoUpgrade UpgradeGlobalVariables will upgrade the
2-field form (add i8* null as the third field).
Reviewed By: rnk, dexonsmith
Differential Revision: https://reviews.llvm.org/D61547
llvm-svn: 360742
The condition !AddrPool.empty() is tested before attachRangesOrLowHighPC(), which may add an entry to AddrPool. We emit DW_AT_low_pc (DW_FORM_addrx) but may incorrectly omit DW_AT_addr_base for LineTablesOnly. This can be easily reproduced:
clang -gdwarf-5 -gmlt -c a.cc
Fix this by moving !AddrPool.empty() below.
This was discovered while investigating an lld crash (fixed by D61889) on such object files: ld.lld --gdb-index a.o
Reviewed By: probinson
Differential Revision: https://reviews.llvm.org/D61891
llvm-svn: 360678
Follow up to r359122, after a bug was reported in it - the original
change too aggressively tried to move related types out of type units,
which included unnamed types (like array types) which can't reasonably
be declared-but-not-defined.
A step beyond that is that some types in type units can be anonymous, if
they are types with a name for linkage purposes (eg: "typedef struct { }
x;"). So ensure those don't get turned into plain declarations (without
signatures) because, lacking names, they can't be resolved to the
definition.
[Also include a fix for llvm-dwarfdump/libDebugInfoDWARF to pretty print
types in type units]
llvm-svn: 360458
In certain circumstances, optimizations pick line numbers from debug
intrinsic instructions as the new location for altered instructions. This
is problematic because the line number of a debugging intrinsic is
meaningless (it doesn't produce any machine instruction), only the scope
information is valid. The result can be the line number of a variable
declaration "leaking" into real code from debugging intrinsics, making the
line table un-necessarily jumpy, and potentially different with / without
variable locations.
Fix this by using zero line numbers when promoting dbg.declare intrinsics
into dbg.values: this is safe for debug intrinsics as their line numbers
are meaningless, and reduces the scope for damage / misleading stepping
when optimizations pick locations from the wrong place.
Differential Revision: https://reviews.llvm.org/D59272
llvm-svn: 360415
as it was causing significant compile time regressions.
This reverts commit r359426 while we come up with testcases and additional ideas.
llvm-svn: 360301
DWARF5, 2.12 20ff says that
Any debugging information entry representing a pointer or reference
type [may have a DW_AT_address_class attribute].
The existing code (https://reviews.llvm.org/D29670) seems to take a
quite literal interpretation of that wording. I don't see a reason why
an rvalue reference isn't a reference type in the spirit of that
paragraph. This patch allows rvalue references to also have address
spaces.
rdar://problem/50511483
Differential Revision: https://reviews.llvm.org/D61625
llvm-svn: 360176
This fixes the https://bugs.llvm.org/show_bug.cgi?id=41355.
Previously with -r we printed relocation section name instead of the target section name.
It was like this: "RELOCATION RECORDS FOR [.rel.text]"
Now it is: "RELOCATION RECORDS FOR [.text]"
Also when relocation target section has more than one relocation section,
we did not combine the output. Now we do.
Differential revision: https://reviews.llvm.org/D61312
llvm-svn: 360143
Summary:
Prior to DWARF v5, a directory index of 0 represents DW_AT_comp_dir.
In DWARF v5, the index starts with 0 and Entry.DirIdx is the index into
Prologue.IncludeDirectories.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D61253
llvm-svn: 360015
-t is --symbols in llvm-readobj but --section-details (unimplemented) in readelf.
The confusing option should not be used since we aim for improving
compatibility.
Keep just one llvm-readobj -t use case in test/tools/llvm-readobj/symbols.test
llvm-svn: 359661
We use both -long-option and --long-option in tests. Switch to --long-option for consistency.
In the "llvm-readelf" mode, -long-option is discouraged as it conflicts with grouped short options and it is not accepted by GNU readelf.
While updating the tests, change llvm-readobj -s to llvm-readobj -S to reduce confusion ("s" is --section-headers in llvm-readobj but --symbols in llvm-readelf).
llvm-svn: 359649
Summary:
Prior to this patch, the CommandLine parser would strip an
unlimitted number of dashes from options. This patch limits it to
two.
Reviewers: rnk
Reviewed By: rnk
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61229
llvm-svn: 359480
This patch fixes PR40795, where constant-valued variable locations can
"leak" into blocks placed at higher addresses. The root of this is that
DbgEntityHistoryCalculator terminates all register variable locations at
the end of each block, but not constant-value variable locations.
Fixing this requires constant-valued DBG_VALUE instructions to be
broadcast into all blocks where the variable location remains valid, as
documented in the LiveDebugValues section of SourceLevelDebugging.rst,
and correct termination in DbgEntityHistoryCalculator.
Differential Revision: https://reviews.llvm.org/D59431
llvm-svn: 359426
While this doesn't come up in reasonable cases currently (the only user
defined types not in type units are ones without linkage - which makes
for near-ODR violations, because it'd be a type with linkage referencing
a type without linkage - such a type can't be validly defined in more
than one TU, so arguably it shouldn't be in a type unit to begin with -
but it's a convenient way to demonstrate an issue that will become more
revalent with homed modular debug info type definitions - which also
don't need to be in type units but more legitimately so).
Precursor to the Clang change to de-type-unit (by omitting the
'identifier') types homed due to strong linkage vtables. (making that
change without this one would lead to major type duplication in type
units)
llvm-svn: 359122
Originally committed in r358931
Reverted in r358997
Seems this change made Apple accelerator tables miss names (because
names started respecting the CU NameTableKind GNU & assuming that
shouldn't produce accelerated names too), which is never correct (apple
accelerator tables don't have separators or CU lists - if present, they
must describe all names in all CUs).
Original Description:
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
llvm-svn: 359026
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
llvm-svn: 358931
This is a follow-up to r291037+r291258, which used null debug locations
to prevent jumpy line tables.
Using line 0 locations achieves the same effect, but works better for
crash attribution because it preserves the right inline scope.
Differential Revision: https://reviews.llvm.org/D60913
llvm-svn: 358791
Summary:
When calculating the debug value history, DbgEntityHistoryCalculator
would only keep track of register clobbering for the latest debug value
per inlined entity. This meant that preceding register-described debug
value fragments would live on until the next overlapping debug value,
ignoring any potential clobbering. This patch amends
DbgEntityHistoryCalculator so that it keeps track of all registers that
a inlined entity's currently live debug values are described by.
The DebugInfo/COFF/pieces.ll test case has had to be changed since
previously a register-described fragment would incorrectly outlive its
basic block.
The parent patch D59941 is expected to increase the coverage slightly,
as it makes sure that location list entries are inserted after clobbered
fragments, and this patch is expected to decrease it, as it stops
preceding register-described from living longer than they should. All in
all, this patch and the preceding patch has a negligible effect on the
output from `llvm-dwarfdump -statistics' for a clang-3.4 binary built
using the RelWithDebInfo build profile. "Scope bytes covered" increases
by 0.5%, and "variables with location" increases from 2212083 to
2212088, but it should improve the accuracy quite a bit.
This fixes PR40283.
Reviewers: aprantl, probinson, dblaikie, rnk, bjope
Reviewed By: aprantl
Subscribers: llvm-commits
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D59942
llvm-svn: 358073
Summary:
Currently the DbgValueHistorymap only keeps track of clobbered registers
for the last debug value that it has encountered. This could lead to
preceding register-described debug values living on longer in the
location lists than they should. See PR40283 for an example. This
patch does not introduce tracking of multiple registers, but changes
the DbgValueHistoryMap structure to allow for that in a follow-up
patch. This patch is not NFC, as it at least fixes two bugs in
DwarfDebug (both are covered in the new clobbered-fragments.mir test):
* If a debug value was clobbered (its End pointer set), the value would
still be added to OpenRanges, meaning that the succeeding location list
entries could potentially contain stale values.
* If a debug value was clobbered, and there were non-overlapping
fragments that were still live after the clobbering, DwarfDebug would
not create a location list entry starting directly after the
clobbering instruction. This meant that the location list could have
a gap until the next debug value for the variable was encountered.
Before this patch, the history map was represented by <Begin, End>
pairs, where a new pair was created for each new debug value. When
dealing with partially overlapping register-described debug values, such
as in the following example:
DBG_VALUE $reg2, $noreg, !1, !DIExpression(DW_OP_LLVM_fragment, 32, 32)
[...]
DBG_VALUE $reg3, $noreg, !1, !DIExpression(DW_OP_LLVM_fragment, 64, 32)
[...]
$reg2 = insn1
[...]
$reg3 = insn2
the history map would then contain the entries `[<DV1, insn1>, [<DV2, insn2>]`.
This would leave it up to the users of the map to be aware of
the relative order of the instructions, which e.g. could make
DwarfDebug::buildLocationList() needlessly complex. Instead, this patch
makes the history map structure monotonically increasing by dropping the
End pointer, and replacing that with explicit clobbering entries in the
vector. Each debug value has an "end index", which if set, points to the
entry in the vector that ends the debug value. The ending entry can
either be an overlapping debug value, or an instruction which clobbers
the register that the debug value is described by. The ending entry's
instruction can thus either be excluded or included in the debug value's
range. If the end index is not set, the debug value that the entry
introduces is valid until the end of the function.
Changes to test cases:
* DebugInfo/X86/pieces-3.ll: The range of the first DBG_VALUE, which
describes that the fragment (0, 64) is located in RDI, was
incorrectly ended by the clobbering of RAX, which the second
(non-overlapping) DBG_VALUE was described by. With this patch we
get a second entry that only describes RDI after that clobbering.
* DebugInfo/ARM/partial-subreg.ll: This test seems to indiciate a bug
in LiveDebugValues that is caused by it not being aware of fragments.
I have added some comments in the test case about that. Also, before
this patch DwarfDebug would incorrectly include a register-described
debug value from a preceding block in a location list entry.
Reviewers: aprantl, probinson, dblaikie, rnk, bjope
Reviewed By: aprantl
Subscribers: javed.absar, kristof.beyls, jdoerfert, llvm-commits
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D59941
llvm-svn: 358072
COMMON blocks are a feature of Fortran that has no direct analog in C languages, but they are similar to data sections in assembly language programming. A COMMON block is a named area of memory that holds a collection of variables. Fortran subprograms may map the COMMON block memory area to their own, possibly distinct, non-empty list of variables. A Fortran COMMON block might look like the following example.
COMMON /ALPHA/ I, J
For this construct, the compiler generates a new scope-like DI construct (!DICommonBlock) into which variables (see I, J above) can be placed. As the common block implies a range of storage with global lifetime, the !DICommonBlock refers to a !DIGlobalVariable. The Fortran variable that comprise the COMMON block are also linked via metadata to offsets within the global variable that stands for the entire common block.
@alpha_ = common global %alphabytes_ zeroinitializer, align 64, !dbg !27, !dbg !30, !dbg !33!14 = distinct !DISubprogram(…)
!20 = distinct !DICommonBlock(scope: !14, declaration: !25, name: "alpha")
!25 = distinct !DIGlobalVariable(scope: !20, name: "common alpha", type: !24)
!27 = !DIGlobalVariableExpression(var: !25, expr: !DIExpression())
!29 = distinct !DIGlobalVariable(scope: !20, name: "i", file: !3, type: !28)
!30 = !DIGlobalVariableExpression(var: !29, expr: !DIExpression())
!31 = distinct !DIGlobalVariable(scope: !20, name: "j", file: !3, type: !28)
!32 = !DIExpression(DW_OP_plus_uconst, 4)
!33 = !DIGlobalVariableExpression(var: !31, expr: !32)
The DWARF generated for this is as follows.
DW_TAG_common_block:
DW_AT_name: alpha
DW_AT_location: @alpha_+0
DW_TAG_variable:
DW_AT_name: common alpha
DW_AT_type: array of 8 bytes
DW_AT_location: @alpha_+0
DW_TAG_variable:
DW_AT_name: i
DW_AT_type: integer*4
DW_AT_location: @Alpha+0
DW_TAG_variable:
DW_AT_name: j
DW_AT_type: integer*4
DW_AT_location: @Alpha+4
Patch by Eric Schweitz!
Differential Revision: https://reviews.llvm.org/D54327
llvm-svn: 357934
Summary:
This avoids needing an isel pattern for each condition code. And it removes translation switches for converting between Jcc instructions and condition codes.
Now the printer, encoder and disassembler take care of converting the immediate. We use InstAliases to handle the assembly matching. But we print using the asm string in the instruction definition. The instruction itself is marked IsCodeGenOnly=1 to hide it from the assembly parser.
Reviewers: spatel, lebedev.ri, courbet, gchatelet, RKSimon
Reviewed By: RKSimon
Subscribers: MatzeB, qcolombet, eraman, hiraditya, arphaman, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60228
llvm-svn: 357802
Currently, YAML has the following syntax for describing the symbols:
Symbols:
Local:
LocalSymbol1:
...
LocalSymbol2:
...
...
Global:
GlobalSymbol1:
...
Weak:
...
GNUUnique:
I.e. symbols are grouped by their bindings. That is not very convenient,
because:
It does not allow to set a custom binding, what can be useful for producing
broken/special outputs for test cases. Adding a new binding would require to
change a syntax (what we observed when added GNUUnique recently).
It does not allow to change the order of the symbols in .symtab/.dynsym,
i.e. currently all Local symbols are placed first, then Global, Weak and GNUUnique
are following, but we are not able to change the order.
It is not consistent. Binding is just one of the properties of the symbol,
we do not group them by other properties.
It makes the code more complex that it can be. This patch shows it can be simplified
with the change performed.
The patch changes the syntax to just:
Symbols:
Symbol1:
...
Symbol2:
...
...
With that, we are able to work with the binding field just like with any other symbol property.
Differential revision: https://reviews.llvm.org/D60122
llvm-svn: 357595
Summary:
This considers module symbol streams and the global symbol stream to be
roots. Most types that this considers "unreferenced" are referenced by
LF_UDT_MOD_SRC_LINE id records, which VC seems to always include.
Essentially, they are types that the user can only find in the debugger
if they call them by name, they cannot be found by traversing a symbol.
In practice, around 80% of type information in a PDB is referenced by a
symbol. That seems like a reasonable number.
I don't really plan to do anything with this tool. It mostly just exists
for informational purposes, and to confirm that we probably don't need
to implement type reference tracking in LLD. We can continue to merge
all types as we do today without wasting space.
Reviewers: zturner, aganea
Subscribers: mgorny, hiraditya, arphaman, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59620
llvm-svn: 356692
The 2nd loop calculates spill costs but reports free registers as cost
0 anyway, so there is little benefit from having a separate early
loop.
Surprisingly this is not NFC, as many register are marked regDisabled
so the first loop often picks up later registers unnecessarily instead
of the first one available in the allocation order...
Patch by Matthias Braun
llvm-svn: 356499
Moving subprogram specific flags into DISPFlags makes IR code more readable.
In addition, we provide free space in DIFlags for other
'non-subprogram-specific' debug info flags.
Patch by Djordje Todorovic.
Differential Revision: https://reviews.llvm.org/D59288
llvm-svn: 356454
Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows
for a convenient way to perform type conversions on the Dwarf expression
stack. As an additional bonus it paves the way for using other Dwarf
v5 ops that need to reference a base_type.
The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp
to perform sext/zext on debug values but mainly the patch is about
preparing terrain for adding other Dwarf v5 ops that need to reference a
base_type.
For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a
complex shift & mask pattern is generated to emulate sext/zext.
This is a recommit of r356442 with trivial fixes for the failing tests.
Differential Revision: https://reviews.llvm.org/D56587
llvm-svn: 356451
Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows
for a convenient way to perform type conversions on the Dwarf expression
stack. As an additional bonus it paves the way for using other Dwarf
v5 ops that need to reference a base_type.
The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp
to perform sext/zext on debug values but mainly the patch is about
preparing terrain for adding other Dwarf v5 ops that need to reference a
base_type.
For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a
complex shift & mask pattern is generated to emulate sext/zext.
Differential Revision: https://reviews.llvm.org/D56587
llvm-svn: 356442
Summary:
Look past bitcasts when looking for parameter debug values that are
described by frame-index loads in `EmitFuncArgumentDbgValue()`.
In the attached test case we would be left with an undef `DBG_VALUE`
for the parameter without this patch.
A similar fix was done for parameters passed in registers in D13005.
This fixes PR40777.
Reviewers: aprantl, vsk, jmorse
Reviewed By: aprantl
Subscribers: bjope, javed.absar, jdoerfert, llvm-commits
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D58831
llvm-svn: 356363
This indicates an intrinsic parameter is required to be a constant,
and should not be replaced with a non-constant value.
Add the attribute to all AMDGPU and generic intrinsics that comments
indicate it should apply to. I scanned other target intrinsics, but I
don't see any obvious comments indicating which arguments are intended
to be only immediates.
This breaks one questionable testcase for the autoupgrade. I'm unclear
on whether the autoupgrade is supposed to really handle declarations
which were never valid. The verifier fails because the attributes now
refer to a parameter past the end of the argument list.
llvm-svn: 355981
Summary:
Swift now generates PDBs for debugging on Windows. llvm and lldb
need a language enumerator value too properly handle the output
emitted by swiftc.
Subscribers: jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59231
llvm-svn: 355882
Summary:
This patch works around the bug in the ptxas tool with the processing of bytes
separated by the comma symbol. The emission of the packed string is
temporarily disabled.
Reviewers: tra
Subscribers: jholewinski, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59148
llvm-svn: 355740
Summary:
If the LLVM module shows that it has debug info, but the file is
actually empty and the real debug info is not emitted, the ptxas tool
emits error 'Debug information not found in presence of .target debug'.
We need at leas one empty debug section to silence this message. Section
`.debug_loc` is not emitted for PTX and we can emit empty `.debug_loc`
section if `debug` option was emitted.
Reviewers: tra
Subscribers: jholewinski, aprantl, llvm-commits
Differential Revision: https://reviews.llvm.org/D57250
llvm-svn: 355719
When using full LTO it is possible that template function definition DIE
is bound to one compilation unit and it's declaration to another. We should
add function declaration attributes on behalf of its owner CU otherwise
we may end up with malformed file identifier in function declaration
DW_AT_decl_file attribute.
Differential revision: https://reviews.llvm.org/D58538
llvm-svn: 354978
Summary:
A store to an object whose lifetime is about to end can be removed.
See PR40550 for motivation.
Reviewers: niravd
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D57541
llvm-svn: 354244
In this patch SelectionDAG tries to salvage any dbg.values that are going to be
dropped, in case they can be recovered from Values in the current BB. It also
strengthens SelectionDAGs handling of dangling debug data, so that dbg.values
are *always* emitted (as Undef or otherwise) instead of dangling forever.
The motivation behind this patch exists in the new test case: a memory address
(here a bitcast and GEP) exist in one basic block, and a dbg.value referring to
the address is left in the 'next' block. The base pointer is live across all
basic blocks. In current llvm trunk the dbg.value cannot be encoded, and it
isn't even emitted as an Undef DBG_VALUE.
The change is simply: if we're definitely going to drop a dbg.value, repeatedly
apply salvageDebugInfo to its operand until either we find something that can
be encoded, or we can't salvage any further in which case we produce an Undef
DBG_VALUE. To know when we're "definitely going to drop a dbg.value",
SelectionDAG signals SelectionDAGBuilder when all IR instructions have been
encoded to force salvaging. This ensures that any dbg.value that's dangling
after DAG creation will have a corresponding DBG_VALUE encoded.
Differential Revision: https://reviews.llvm.org/D57694
llvm-svn: 353954
SelectionDAGBuilder has special handling for dbg.value intrinsics that are
understood to define the location of function parameters on entry to the
function. To enable this, we avoid recording a dbg.value as a virtual register
reference if it might be such a parameter, so that it later hits
EmitFuncArgumentDbgValue.
This patch reduces the set of circumstances where we avoid recording a
dbg.value as a virtual register reference, to allow more "normal" variables
to be recorded that way. We now only bypass for potential parameters if:
* The dbg.value operand is an Argument,
* The Variable is a parameter, and
* The Variable is not inlined.
meaning it's very likely that the dbg.value is a function-entry parameter
location.
Differential Revision: https://reviews.llvm.org/D57584
llvm-svn: 353948
Summary:
This is a follow-up to D57510. This patch stops DebugHandlerBase from
changing the starting label for the first non-overlapping,
register-described parameter DBG_VALUEs to the beginning of the
function. That code did not consider what defined the registers, which
could result in the ranges for the debug values starting before their
defining instructions. We currently do not emit debug values for
constant values directly at the start of the function, so this code is
still useful for such values, but my intention is to remove the code
from DebugHandlerBase completely when we get there. One reason for
removing it is that the code violates the history map's ranges, which I
think can make it quite confusing when troubleshooting.
In D57510, PrologEpilogInserter was amended so that parameter DBG_VALUEs
now are kept at the start of the entry block, even after emission of
prologue code. That was done to reduce the degradation of debug
completeness from this patch. PR40638 is another example, where the
lexical-scope trimming that LDV does, in combination with scheduling,
results in instructions after the prologue being left without locations.
There might be other cases where the DBG_VALUEs are pushed further down,
for which the DebugHandlerBase code may be helpful, but as it now quite
often result in incorrect locations, even after the prologue, it seems
better to remove that code, and try to work our way up with accurate
locations.
In the long run we should maybe not aim to provide accurate locations
inside the prologue. Some single location descriptions, at least those
referring to stack values, generate inaccurate values inside the
epilogue, so we maybe should not aim to achieve accuracy for location
lists. However, it seems that we now emit line number programs that can
result in GDB and LLDB stopping inside the prologue when doing line
number stepping into functions. See PR40188 for more information.
A summary of some of the changed test cases is available in PR40188#c2.
Reviewers: aprantl, dblaikie, rnk, jmorse
Reviewed By: aprantl
Subscribers: jdoerfert, jholewinski, jvesely, javed.absar, llvm-commits
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D57511
llvm-svn: 353928
Salvaging a redundant load instruction into a debug expression hides a
memory read from optimisation passes. Passes that alter memory behaviour
(such as LICM promoting memory to a register) aren't aware of these debug
memory reads and leave them unaltered, making the debug variable location
point somewhere unsafe.
Teaching passes to know about these debug memory reads would be challenging
and probably incomplete. Finding dbg.value instructions that need to be fixed
would likely be computationally expensive too, as more analysis would be
required. It's better to not generate debug-memory-reads instead, alas.
Changed tests:
* DeadStoreElim: test for salvaging of intermediate operations contributing
to the dead store, instead of salvaging of the redundant load,
* GVN: remove debuginfo behaviour checks completely, this behaviour is still
covered by other tests,
* InstCombine: don't test for salvaged loads, we're removing that behaviour.
Differential Revision: https://reviews.llvm.org/D57962
llvm-svn: 353824
Summary:
This is a preparatory change for removing the code from
DebugHandlerBase::beginFunction() which changes the starting label for
the first non-overlapping DBG_VALUEs of parameters to the beginning of
the function. It does that to be able to show parameters when entering a
function. However, that code does not consider what defines the values,
which can result in the ranges for the debug values starting before
their defining instructions. That code is removed in a follow-up patch.
When prologue code is inserted, it leads to DBG_VALUEs that start
directly in the entry block being moved down after the prologue
instructions. This patch fixes that by stashing away DBG_VALUEs for
parameters before emitting the prologue, and then reinserts them at the
start of the block. This assumes that there is no target that somehow
clobbers parameter registers in the frame setup; there is no such case
in the lit tests at least.
See PR40188 for more information.
Reviewers: aprantl, dblaikie, rnk, jmorse
Reviewed By: aprantl
Subscribers: bjope, llvm-commits
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D57510
llvm-svn: 353823
This configuration (due to r349207) was intended not to emit any DWO CU,
but a degenerate CU was still being emitted - containing a header and a
DW_TAG_compile_unit with no attributes.
Under that situation, emit nothing to the .dwo file. (since this is a
dynamic property of the input the .dwo file is still emitted, just with
nothing in it (so a valid, but empty, ELF file) - if some other CU
didn't satisfy this criteria, its DWO CU would still go there, etc)
llvm-svn: 353771
Summary:
This patch fixes PR40587.
When a dbg.value instrinsic is emitted to the DAG
by using EmitFuncArgumentDbgValue the resulting
DBG_VALUE is hoisted to the beginning of the entry
block. I think the idea is to be able to locate
a formal argument already from the start of the
function.
However, EmitFuncArgumentDbgValue only checked that
the value that was used to describe a variable was
originating from a function parameter, not that the
variable itself actually was an argument to the
function. So when for example assigning a local
variable "local" the value from an argument "a",
the assocated DBG_VALUE instruction would be hoisted
to the beginning of the function, even if the scope
for "local" started somewhere else (or if "local"
was mapped to other values earlier in the function).
This patch adds some logic to EmitFuncArgumentDbgValue
to check that the variable being described actually
is an argument to the function. And that the dbg.value
being lowered already is in the entry block. Otherwise
we bail out, and the dbg.value will be handled as an
ordinary dbg.value (not as a "FuncArgumentDbgValue").
A tricky situation is when both the variable and
the value is related to function arguments, but not
neccessarily the same argument. We make sure that we
do not describe the same argument more than once as
a "FuncArgumentDbgValue". This solution works as long
as opt has injected a "first" dbg.value that corresponds
to the formal argument at the function entry.
Reviewers: jmorse, aprantl
Subscribers: jyknight, hiraditya, fedor.sergeev, dstenb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57702
llvm-svn: 353735
Summary:
rL189250 added a realpath call, and rL352916 because realpath breaks assumptions with some build systems. However, the /usr/lib/debug case has been clarified, falling back to /usr/lib/debug is currently broken if the obj passed in is a relative path. Adding a call to use absolute paths when falling back to /usr/lib/debug fixes that while still not making any realpath assumptions.
This also adds a --fallback-debug-path command line flag for testing (since we probably can't write to /usr/lib/debug from buildbot environments), but was also verified manually:
```
$ rm -f path/to/dwarfdump-test.elf-x86-64
$ strace llvm-symbolizer --obj=relative/path/to/dwarfdump-test.elf-x86-64.debuglink 0x40113f |& grep dwarfdump
```
Lookups went to relative/path/to/dwarfdump-test.elf-x86-64, relative/path/to/.debug/dwarfdump-test.elf-x86-64, and then finally /usr/lib/debug/absolute/path/to/dwarfdump-test.elf-x86-64.
Reviewers: dblaikie, samsonov
Reviewed By: dblaikie
Subscribers: krytarowski, aprantl, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57916
llvm-svn: 353730
When a landing pad is calculated in a program that is compiled for micromips
with -fPIC flag, it will point to an even address.
Such an error will cause a segmentation fault, as the instructions in
micromips are aligned on odd addresses. This patch sets the last bit of the
offset where a landing pad is, to 1, which will effectively be an odd
address and point to the instruction exactly.
r344591 fixed this issue for -static compilation.
Patch by Aleksandar Beserminji.
Differential Revision: https://reviews.llvm.org/D57677
llvm-svn: 353480
This patch adds half a dozen new tests that test various edge cases in
the behaviour of the symbolizer and DWARF data parsing. All of them test
the current behaviour.
Reviewed by: JDevlieghere, aprantl
Differential Revision: https://reviews.llvm.org/D57741
llvm-svn: 353286
Summary:
According to
https://docs.nvidia.com/cuda/archive/10.0/ptx-writers-guide-to-interoperability/index.html#cuda-specific-dwarf,
the compiler should emit the DW_AT_address_class attribute for all
variable and parameter. It means, that DW_AT_address_class attribute
should be used in the non-standard way to support compatibility with the
cuda-gdb debugger.
Clang is able to generate the information about the variable address
class. This information is emitted as the expression sequence
`DW_OP_constu <DWARF Address Space> DW_OP_swap DW_OP_xderef`. The patch
tries to find all such expressions and transform them into
`DW_AT_address_class <DWARF Address Space>` if target is NVPTX and the debugger is gdb.
If the expression is not found, then default values are used. For the
local variables <DWARF Address Space> is set to ADDR_local_space(6), for
the globals <DWARF Address Space> is set to ADDR_global_space(5). The
values are taken from the table in the same section 5.2. CUDA-Specific
DWARF Definitions.
Reviewers: echristo, probinson
Subscribers: jholewinski, aprantl, llvm-commits
Differential Revision: https://reviews.llvm.org/D57157
llvm-svn: 353203
The LiveDebugValues pass recognizes spills but not restores, which can
cause large gaps in location information for some variables, depending
on control flow. This patch make LiveDebugValues recognize restores and
generate appropriate DBG_VALUE instructions.
This patch was posted previously with r352642 and reverted in r352666 due
to buildbot errors. A missing return statement was the cause for the
failures.
Reviewers: aprantl, NicolaPrica
Differential Revision: https://reviews.llvm.org/D57271
llvm-svn: 353089
Summary:
Using realpath makes assumptions about build systems that do not always hold true. The debug binary referred to from the .gnu_debuglink should exist in the same directory (or in a .debug directory, etc.), but the files may only exist as symlinks to a differently named files elsewhere, and using realpath causes that lookup to fail.
This was added in r189250, and this is basically a revert + regression test case.
Reviewers: dblaikie, samsonov, jhenderson
Reviewed By: dblaikie
Subscribers: llvm-commits, hiraditya
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57609
llvm-svn: 352916
Prior to this change, there are a few tests called llvm-symbolizer* in
the DebugInfo test area. These really were testing either the DebugInfo
or Symbolizer library, rather than the llvm-symbolizer tool itself, so
this patch renames them to be clearer that they aren't explicitly tests
for llvm-symbolizer (such tests belong in test/tools/llvm-symbolizer).
This patch also reinstates the copying of a DWO file, removed previously
in r352752. The test needs this so that it could possibly fail.
Finally, some of the tests have been simplified slightly by removing
unnecessary switches and/or unused check-prefixes.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D57518
llvm-svn: 352847
This is the fourth (and final for now) of a series of patches
simplifying llvm-symbolizer tests. See r352752, r352753 and 352754 for
the previous ones. This patch splits out several more distinct test
cases from llvm-symbolizer.test into separate tests, and simplifies them
in various ways including:
1) Building a test case for spaces in path from source, rather than
using a pre-canned binary. This allows deleting of said binary and the
source it was built from.
2) Switching to specifying addresses and objects directly on the
command-line rather than via stdin.
This also adds an explict test for the ability to specify a file and
address as a line in stdin, since the majority of the tests have been
migrated away from this approach, leaving this largely untested.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D57446
llvm-svn: 352756
This is the third of a series of patches simplifying llvm-symbolizer
tests. See r352752 and r352753 for the previous two. This patch splits
out a number of distinct test cases from llvm-symbolizer.test into
separate tests, and simplifies them in various ways including:
1) using --obj/positional arguments for the input file and addresses
instead of stdin,
2) using runtime-generated inputs rather than a pre-canned binary, and
3) testing more specifically (i.e. checking only what is interesting to
the behaviour changed in the original commit for that test case).
This patch also removes the test case for using --obj. The
tools/llvm-symbolizer/basic.s test already tests this case. Finally,
this patch adds a simple test case to the demangle switch test case to
show that demangling happens by default.
See https://bugs.llvm.org/show_bug.cgi?id=40070#c1 for the motivation.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D57446
llvm-svn: 352754
This is the second of a series of patches simplifying llvm-symbolizer
tests. See r352752 for the first. This one splits out 5 distinct test
cases from llvm-symbolizer.test into separate tests, and simplifies them
slightly by using --obj/positional arguments for the input file and
addresses instead of stdin.
See https://bugs.llvm.org/show_bug.cgi?id=40070#c1 for the motivation.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D57443
llvm-svn: 352753
This change migrates most llvm-symbolizer tests away from reading input
via stdin and instead using --obj + positional arguments for the file
and addresses respectively, which makes the tests easier to read.
One exception is the test test/tools/llvm-symbolizer/pdb/pdb.test, which
was doing some manipulation on the input addresses. This patch
simplifies this somewhat, but it still reads from stdin.
More changes to follow to simplify/break-up other tests.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D57441
llvm-svn: 352752
The LiveDebugValues pass recognizes spills but not restores, which can
cause large gaps in location information for some variables, depending
on control flow. This patch make LiveDebugValues recognize restores and
generate appropriate DBG_VALUE instructions.
Reviewers: aprantl, NicolaPrica
Differential Revision: https://reviews.llvm.org/D57271
llvm-svn: 352642
This test started XPASSing with r352467, and the change in behaviour
performed by that patch does appear to fix the cause of the original XFAIL
(missing FrameIndex DBG_VALUE), which I've replicated locally with
-mtriple=powerpc64--.
I'll write this up in PR21881 which documents the XFAIL, and seek
confirmation I haven't overlooked something here.
llvm-svn: 352471
A FrameIndex should be valid throughout a block regardless of what instructions
get selected in that block -- therefore we shouldn't harness dbg.values that
refer to FrameIndexes to an SDNode. There are numerous codegen reasons why
an SDNode never appears or doesn't become a location that a DBG_VALUE can
refer to. None of them actually affect the variable location.
Therefore, before any other tests to encode dbg_values in a SelectionDAG,
identify FrameIndex operands and encode them unattached to any SDNode.
Differential Revision: https://reviews.llvm.org/D57328
llvm-svn: 352467
This patch improves the placement of DBG_VALUEs when by SelectionDAG, which
as documented in PR40427 can go very wrong. At the core of this is
ProcessSourceNode, which assumes the last instruction in a BB is the start
of the last processed IR instruction, which isn't always true.
Instead, use a helper function to call InstrEmitter::EmitNode, that records
before-and-after iterators and determines the first of any new instruction
created during emission. This is passed to ProcessSourceNode, which can
then make more elightened decisions about ordering for DBG_VALUE placement.
Differential revision: https://reviews.llvm.org/D57163
llvm-svn: 352350
If bottom of block BB has only one successor OldTop, in most cases it is profitable to move it before OldTop, except the following case:
-->OldTop<-
| . |
| . |
| . |
---Pred |
| |
BB-----
Move BB before OldTop can't reduce the number of taken branches, this patch detects this case and prevent the moving.
Differential Revision: https://reviews.llvm.org/D57067
llvm-svn: 352236
This reapplies commit r351987 with a failed test fix. Now the test
accepts both DW_OP_GNU_push_tls_address and DW_OP_form_tls_address
opcode.
Original commit message:
```
This is a fix for a regression introduced by the rL348194 commit. In
that change new type (MEK_DTPREL) of MipsMCExpr expression was added,
but in some places of the code this type of expression considered as
unexpected.
This change fixes the bug. The MEK_DTPREL type of expression is used for
marking TLS DIEExpr only and contains a regular sub-expression. Where we
need to handle the expression, we retrieve the sub-expression and
handle it in a common way.
```
llvm-svn: 352034
Pulling out the split-dwarf tests by way of example of how I think
llvm-symbolizer should be tested going forward. Open to
debate/discussion, though.
llvm-svn: 352004
This is a fix for a regression introduced by the rL348194 commit. In
that change new type (MEK_DTPREL) of MipsMCExpr expression was added,
but in some places of the code this type of expression considered as
unexpected.
This change fixes the bug. The MEK_DTPREL type of expression is used for
marking TLS DIEExpr only and contains a regular sub-expression. Where we
need to handle the expression, we retrieve the sub-expression and
handle it in a common way.
llvm-svn: 351987
Enable full support for the debug info. Recommit to fix the emission of
the not required closing brace.
Differential revision: https://reviews.llvm.org/D46189
llvm-svn: 351972
This fixes https://bugs.llvm.org/show_bug.cgi?id=40072.
GNU addr2line's --functions switch is off by default, has a short alias
of -f, and does not take an argument. This patch changes llvm-symbolizer
to allow the second and third point (changing the default behaviour may
have negative impacts on users). If the option is missing a value, it
now treats it as "linkage".
This change does cause one previously valid command-line to behave
differently. Before --functions <value> was accepted, but now only
--functions=<value> is allowed (as well as --functions). The old
behaviour will result in the value being treated as a positional
argument.
The previous testing for --functions=short has been pulled out into a
new test that also tests the other accepted values and option formats.
Reviewed by: ruiu
Differential Revision: https://reviews.llvm.org/D57049
llvm-svn: 351968
Summary:
`CodeViewDebug::lowerTypeMemberFunction` used to default to a `Void`
return type if the function's type array was empty. After D54667, it
started blindly indexing the 0th item for the return type, which fails
in `getOperand` for empty arrays if assertions are enabled.
This patch restores the `Void` return type for empty type arrays, and
adds a test generated by Rust in line-only debuginfo mode.
Reviewers: zturner, rnk
Reviewed By: rnk
Subscribers: hiraditya, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D57070
llvm-svn: 351910
Summary: Enable full support for the debug info.
Reviewers: echristo
Subscribers: jholewinski, aprantl, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D46189
llvm-svn: 351846
Summary: Initial function labels must follow the debug location for the correct relocation info generation.
Reviewers: tra, jlebar, echristo
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D45784
llvm-svn: 351843
Currently we do not always collapse subsequent .loc 0 0 directives. The
reason is that we were checking for a PrevInstLoc which is not set when
we emit a line-0 record. We should only check the LastAsmLine, which
seems to be created exactly for this purpose.
// When we emit a line-0 record, we don't update PrevInstLoc; so look at
// the last line number actually emitted, to see if it was line 0.
unsigned LastAsmLine =
Asm->OutStreamer->getContext().getCurrentDwarfLoc().getLine();
Differential revision: https://reviews.llvm.org/D56767
llvm-svn: 351395
dbg.value intrinsics can appear in blocks where their operand is not used,
meaning the operand never receives an SDNode, and thus no DBG_VALUE will
be created. Get around this by looking to see whether the operand has already
been allocated a virtual register. This allows dbg.values of Phi node and
Values that are used across basic blocks to successfully be translated into
DBG_VALUEs.
Differential Revision: https://reviews.llvm.org/D56678
llvm-svn: 351358
Summary:
Make recoverfp intrinsic target-independent so that it can be implemented for AArch64, etc.
Refer D53541 for the context. Clang counterpart D56748.
Reviewers: rnk, efriedma
Reviewed By: rnk, efriedma
Subscribers: javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D56747
llvm-svn: 351281
Summary:
As described in PR40209, there can be issues in DBG_VALUEs handling when multiple defs present in a BB. This patch
adds logic for detection of related to def DBG_VALUEs and localizes register update and movement to found DBG_VALUEs.
Reviewers: aheejin
Subscribers: mgorny, dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56401
llvm-svn: 351216
compiler identification lines in test-cases.
(Doing so only because it's then easier to search for references which
are actually important and need fixing.)
llvm-svn: 351200
Part of the effort to refactoring frame pointer code generation. We used
to use two function attributes "no-frame-pointer-elim" and
"no-frame-pointer-elim-non-leaf" to represent three kinds of frame
pointer usage: (all) frames use frame pointer, (non-leaf) frames use
frame pointer, (none) frame use frame pointer. This CL makes the idea
explicit by using only one enum function attribute "frame-pointer"
Option "-frame-pointer=" replaces "-disable-fp-elim" for tools such as
llc.
"no-frame-pointer-elim" and "no-frame-pointer-elim-non-leaf" are still
supported for easy migration to "frame-pointer".
tests are mostly updated with
// replace command line args ‘-disable-fp-elim=false’ with ‘-frame-pointer=none’
grep -iIrnl '\-disable-fp-elim=false' * | xargs sed -i '' -e "s/-disable-fp-elim=false/-frame-pointer=none/g"
// replace command line args ‘-disable-fp-elim’ with ‘-frame-pointer=all’
grep -iIrnl '\-disable-fp-elim' * | xargs sed -i '' -e "s/-disable-fp-elim/-frame-pointer=all/g"
Patch by Yuanfang Chen (tabloid.adroit)!
Differential Revision: https://reviews.llvm.org/D56351
llvm-svn: 351049
NVPTX format requires that no labels/label arithmetics is used in the
debug info sections. To avoid possible problems with the adding/modifying the debug info functionality, made these tests more strict.
llvm-svn: 350731
Summary:
This fixes PR39710. In that case we emitted a location list looking like
this:
.Ldebug_loc0:
.quad .Lfunc_begin0-.Lfunc_begin0
.quad .Lfunc_begin0-.Lfunc_begin0
.short 1 # Loc expr size
.byte 85 # DW_OP_reg5
.quad .Lfunc_begin0-.Lfunc_begin0
.quad .Lfunc_end0-.Lfunc_begin0
.short 1 # Loc expr size
.byte 85 # super-register DW_OP_reg5
.quad 0
.quad 0
As seen, the first entry's beginning and ending addresses evalute to 0,
which meant that the entry inadvertently became an "end of list" entry,
resulting in the location list ending sooner than expected.
To fix this, omit all entries with empty ranges. Location list entries
with empty ranges do not have any effect, as specified by DWARF, so we
might as well drop them:
"A location list entry (but not a base address selection or end of list
entry) whose beginning and ending addresses are equal has no effect
because the size of the range covered by such an entry is zero."
Reviewers: davide, aprantl, dblaikie
Reviewed By: aprantl
Subscribers: javed.absar, JDevlieghere, llvm-commits
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D55919
llvm-svn: 350698
Summary:
StoreResults pass does not optimize store instructions anymore because
store instructions don't return results values anymore. Now this pass is
used solely for memory intrinsics, so update the pass name accordingly
and fix outdated pass descriptions as well.
This patch does not change any meaningful behavior, but not marked as
NFC because it changes a comment check line in a test case.
Reviewers: dschuff
Subscribers: mgorny, sbc100, jgravelle-google, sunfiish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56093
llvm-svn: 350669
Fixes crash reported after r347354 for frontends that don't always emit
'this' pointers for methods. Now we will silently produce debug info
that makes functions like this look like static methods, which seems
reasonable.
llvm-svn: 350073
Originally committed in r349333, reverted in r349353.
GCC emitted these unconditionally on/before 4.4/March 2012
Clang emitted these unconditionally on/before 3.5/March 2014
This improves performance when parsing CUs (especially those using split
DWARF) that contain no code ranges (such as the mini CUs that may be
created by ThinLTO importing - though generally they should be/are
avoided, especially for Split DWARF because it produces a lot of very
small CUs, which don't scale well in a bunch of other ways too
(including size)).
The revert was due to a (Google internal) test that had some checked in old
object files missing DW_AT_ranges. That's since been fixed.
llvm-svn: 349968
- When signing return addresses with -msign-return-address=<scope>{+<key>},
either the A key instructions or the B key instructions can be used. To
correctly authenticate the return address, the unwinder/debugger must know
which key was used to sign the return address.
- When and exception is thrown or a break point reached, it may be necessary to
unwind the stack. To accomplish this, the unwinder/debugger must be able to
first authenticate an the return address if it has been signed.
- To enable this, the augmentation string of CIEs has been extended to allow
inclusion of a 'B' character. Functions that are signed using the B key
variant of the instructions should have and FDE whose associated CIE has a 'B'
in the augmentation string.
- One must also be able to preserve these semantics when first stepping from a
high level language into assembly and then, as a second step, into an object
file. To achieve this, I have introduced a new assembly directive
'.cfi_b_key_frame ', that tells the assembler the current frame uses return
address signing with the B key.
- This ensures that the FDE is associated with a CIE that has 'B' in the
augmentation string.
Differential Revision: https://reviews.llvm.org/D51798
llvm-svn: 349895
When deciding lazily whether a CU would be split or non-split I
accidentally dropped some handling for the line tables comp_dir (by
doing it lazily it was too late to be handled properly by the MC line
table code).
Move that bit of the code back to the non-lazy place.
llvm-svn: 349819
Emit static locals within the correct lexical scope so variables with the same
name will not confuse the debugger into getting the wrong value.
Differential Revision: https://reviews.llvm.org/D55336
llvm-svn: 349777
In PDBs, symbol records must be aligned to four bytes. However, in the
object file, symbol records may not be aligned. MSVC does not pad out
symbol records to make sure they are aligned. That means the linker has
to do extra work to insert the padding. Currently, LLD calculates the
required space with alignment, and copies each record one at a time
while padding them out to the correct size. It has a fast path that
avoids this copy when the records are already aligned.
This change fixes a bug in that codepath so that the copy is actually
saved, and tweaks LLVM's symbol record emission to align symbol records.
Here's how things compare when doing a plain clang Release+PDB build:
- objs are 0.65% bigger (negligible)
- link is 3.3% faster (negligible)
- saves allocating 441MB
- new LLD high water mark is ~1.05GB
llvm-svn: 349431
Mucking about simplifying a test case ( https://reviews.llvm.org/D55261 ) I stumbled across something I've hit before - that LLVM's (GCC's does too, FWIW) assembly output includes a hardcode length for a DWARF unit in its header. Instead we could emit a label difference - making the assembly easier to read/edit (though potentially at a slight (I haven't tried to observe it) performance cost of delaying/sinking the length computation into the MC layer).
Fix: Predicated all the changes (including creating the labels, even if they aren't used/needed) behind the NVPTX useSectionsAsReferences, avoiding emitting labels in NVPTX where ptxas can't parse them.
Reviewers: JDevlieghere, probinson, ABataev
Differential Revision: https://reviews.llvm.org/D55281
llvm-svn: 349430
GCC emitted these unconditionally on/before 4.4/March 2012
Clang emitted these unconditionally on/before 3.5/March 2014
This improves performance when parsing CUs (especially those using split
DWARF) that contain no code ranges (such as the mini CUs that may be
created by ThinLTO importing - though generally they should be/are
avoided, especially for Split DWARF because it produces a lot of very
small CUs, which don't scale well in a bunch of other ways too
(including size)).
llvm-svn: 349333
In ThinLTO many split CUs may be effectively empty because of the lack
of support for cross-unit references in split DWARF.
Using a split unit in those cases is just a waste/overhead - and turned
out to be one contributor to a significant symbolizer performance issue
when global variable debug info was being imported (see r348416 for the
primary fix) due to symbolizers seeing CUs with no ranges, assuming
there might still be addresses covered and walking into the split CU to
see if there are any ranges (when that split CU was in a DWP file, that
meant loading the DWP and its index, the index was extra large because
of all these fractured/empty CUs... and so was very expensive to load).
(the 3rd fix which will follow, is to assume that a CU with no ranges is
empty rather than merely missing its CU level range data - and to not
walk into its DIEs (split or otherwise) in search of address information
that is generally not present)
llvm-svn: 349207
Summary:
Any time a symbol record, whether it's S_UDT, S_LOCAL, or S_[GL]DATA32,
references a record type, it should use the complete type index, even if
there's a typedef in the way.
Fixes the compiler part of PR39853.
Reviewers: zturner, aganea
Subscribers: hiraditya, arphaman, llvm-commits
Differential Revision: https://reviews.llvm.org/D55236
llvm-svn: 348902
Temporarily reverts commit r348806 due to strange asm compilation issues in certain modes (combination of asan+cuda+other things). Will provide repro soon.
llvm-svn: 348898
This fixes PR39845. CodeGenPrepare employs a transactional model when
performing optimizations, i.e. it changes the IR to attempt an optimization
and rolls back the change when it finds the change inadequate. It is during
the rollback that references to locals were dropped from debug value
intrinsics. This patch reinstates debuginfo references during rollbacks.
Reviewers: aprantl, vsk
Differential Revision: https://reviews.llvm.org/D55396
llvm-svn: 348896
Mucking about simplifying a test case ( https://reviews.llvm.org/D55261 ) I stumbled across something I've hit before - that LLVM's (GCC's does too, FWIW) assembly output includes a hardcode length for a DWARF unit in its header. Instead we could emit a label difference - making the assembly easier to read/edit (though potentially at a slight (I haven't tried to observe it) performance cost of delaying/sinking the length computation into the MC layer).
Reviewers: JDevlieghere, probinson, ABataev
Differential Revision: https://reviews.llvm.org/D55281
llvm-svn: 348806
Currently, dbg.value's of "nullptr" are dropped when entering a SelectionDAG --
apparently just because of an oversight when recognising Values that are
constant (see PR39787). This patch adds ConstantPointerNull to the list of
constants that can be turned into DBG_VALUEs.
The matter of what bit-value a null pointer constant in LLVM has was raised
in this mailing list thread:
http://lists.llvm.org/pipermail/llvm-dev/2018-December/128234.html
Where it transpires LLVM relies on (IR) null pointers being zero valued,
thus I've baked this assumption into the patch.
Differential Revision: https://reviews.llvm.org/D55227
llvm-svn: 348753
This is a fix for PR39896, where dbg.value's of SDNodes that have been
optimised out do not lead to "DBG_VALUE undef" instructions being created.
Such undef instructions are necessary to terminate earlier variable
ranges, otherwise variable values leak past the point where they're valid.
The "invalidated" flag of SDDbgValue is currently being abused to mean two
things:
* The corresponding SDNode is now invalid
* This SDDbgValue should not be emitted
Of which there are several legitimate combinations of meaning:
* The SDNode has been invalidated and we should emit "DBG_VALUE undef"
* The SDNode has been invalidated but the debug data was salvaged, don't
emit anything for this SDDbgValue
* This SDDbgValue has been emitted
This patch introduces distinct "Emitted" and "Invalidated" fields to the
SDDbgValue class, updates users accordingly, and generates "undef"
DBG_VALUEs for invalidated records. Awkwardly, there are circumstances
where we emit SDDbgValue's twice, specifically DebugInfo/X86/dbg-addr-dse.ll
which I've preserved.
Differential Revision: https://reviews.llvm.org/D55372
llvm-svn: 348751
VarStreamArray was built on the assumption that it is backed by a
StreamRef, and offset 0 of that StreamRef is the first byte of the first
record in the array.
This is a logical and intuitive assumption, but unfortunately we have
use cases where it doesn't hold. Specifically, a PDB module's symbol
stream is prefixed by 4 bytes containing a magic value, and the first
byte of record data in the array is actually at offset 4 of this byte
sequence.
Previously, we would just truncate the first 4 bytes and then construct
the VarStreamArray with the resulting StreamRef, so that offset 0 of the
underlying stream did correspond to the first byte of the first record,
but this is problematic, because symbol records reference other symbol
records by the absolute offset including that initial magic 4 bytes. So
if another record wants to refer to the first record in the array, it
would say "the record at offset 4".
This led to extremely confusing hacks and semantics in loading code, and
after spending 30 minutes trying to get some math right and failing, I
decided to fix this in the underlying implementation of VarStreamArray.
Now, we can say that a stream is skewed by a particular amount. This
way, when we access a record by absolute offset, we can use the same
values that the records themselves contain, instead of having to do
fixups.
Differential Revision: https://reviews.llvm.org/D55344
llvm-svn: 348499
Summary:
If the output of debug directives only is requested, we should drop
emission of ',debug' option from the target directive. Required for
supporting of nvprof profiler.
Reviewers: echristo
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46061
llvm-svn: 348497
Summary:
We may end up with not emitted debug directives at the end of the module
emission. Patch fixes this problem emitting those last directives the
end of the module emission.
Reviewers: echristo
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D54320
llvm-svn: 348495
This patch adds BPF Debug Format (BTF) as a standalone
LLVM debuginfo. The BTF related sections are directly
generated from IR. The BTF debuginfo is generated
only when the compilation target is BPF.
What is BTF?
============
First, the BPF is a linux kernel virtual machine
and widely used for tracing, networking and security.
https://www.kernel.org/doc/Documentation/networking/filter.txthttps://cilium.readthedocs.io/en/v1.2/bpf/
BTF is the debug info format for BPF, introduced in the below
linux patch
69b693f0ae (diff-06fb1c8825f653d7e539058b72c83332)
in the patch set mentioned in the below lwn article.
https://lwn.net/Articles/752047/
The BTF format is specified in the above github commit.
In summary, its layout looks like
struct btf_header
type subsection (a list of types)
string subsection (a list of strings)
With such information, the kernel and the user space is able to
pretty print a particular bpf map key/value. One possible example below:
Withtout BTF:
key: [ 0x01, 0x01, 0x00, 0x00 ]
With BTF:
key: struct t { a : 1; b : 1; c : 0}
where struct is defined as
struct t { char a; char b; short c; };
How BTF is generated?
=====================
Currently, the BTF is generated through pahole.
https://git.kernel.org/pub/scm/devel/pahole/pahole.git/commit/?id=68645f7facc2eb69d0aeb2dd7d2f0cac0feb4d69
and available in pahole v1.12
https://git.kernel.org/pub/scm/devel/pahole/pahole.git/commit/?id=4a21c5c8db0fcd2a279d067ecfb731596de822d4
Basically, the bpf program needs to be compiled with -g with
dwarf sections generated. The pahole is enhanced such that
a .BTF section can be generated based on dwarf. This format
of the .BTF section matches the format expected by
the kernel, so a bpf loader can just take the .BTF section
and load it into the kernel.
8a138aed4a
The .BTF section layout is also specified in this patch:
with file include/llvm/BinaryFormat/BTF.h.
What use cases this patch tries to address?
===========================================
Currently, only the bpf instruction stream is required to
pass to the kernel. The kernel verifies it, jits it if configured
to do so, attaches it to a particular kernel attachment point,
and later executes when a particular event happens.
This patch tries to expand BTF to support two more use cases below:
(1). BPF supports subroutine calls.
During performance analysis, it would be good to
differentiate which call is hot instead of just
providing a virtual address. This would require to
pass a unique identifier for each subroutine to
the kernel, the subroutine name is a natual choice.
(2). If a particular jitted instruction is hot, we want
user to know which source line this jitted instruction
belongs to. This would require the source information
is available to various profiling tools.
Note that in a single ELF file,
. there may be multiple loadable bpf programs,
. for a particular to-be-loaded bpf instruction stream,
its instructions may come from multiple PROGBITS sections,
the bpf loader needs to merge them together to a single
consecutive insn stream before loading to the kernel.
For example:
section .text: subroutines funcFoo
section _progA: calling funcFoo
section _progB: calling funcFoo
The bpf loader could construct two loadable bpf instruction
streams and load them into the kernel:
. _progA funcFoo
. _progB funcFoo
So per ELF section function offset and instruction offset
will need to be adjusted before passing to the kernel, and
the kernel essentially expect only one code section regardless
of how many in the ELF file.
What do we propose and Why?
===========================
To support the above two use cases, we propose to
add an additional section, .BTF.ext, to the ELF file
which is the input of the bpf loader. A different section
is preferred since loader may need to manipulate it before
loading part of its data to the kernel.
The .BTF.ext section has a similar header to the .BTF section
and it contains two subsections for func_info and line_info.
. the func_info maps the func insn byte offset to a func
type in the .BTF type subsection.
. the line_info maps the insn byte offset to a line info.
. both func_info and line_info subsections are organized
by ELF PROGBITS AX sections.
pahole is not a good place to implement .BTF.ext as
pahole is mostly for structure hole information and more
importantly, we want to pass the actual code to the kernel.
. bpf program typically is small so storage overhead
should be small.
. in bpf land, it is totally possible that
an application loads the bpf program into the
kernel and then that application quits, so
holding debug info by the user space application
is not practical as you may not even know who
loads this bpf program.
. having source codes directly kept by kernel
would ease deployment since the original source
code does not need ship on every hosts and
kernel-devel package does not need to be
deployed even if kernel headers are used.
LLVM is a good place to implement.
. The only reliable time to get the source code is
during compilation time. This will result in both more
accurate information and easier deployment as
stated in the above.
. Another consideration is for JIT. The project like bcc
(https://github.com/iovisor/bcc)
use MCJIT to compile a C program into bpf insns and
load them to the kernel. The llvm generated BTF sections
will be readily available for such cases as well.
Design and implementation of emiting .BTF/.BTF.ext sections
===========================================================
The BTF debuginfo format is defined. Both .BTF and .BTF.ext
sections are generated directly from IR when both
"-target bpf" and "-g" are specified. Note that
dwarf sections are still generated as dwarf is used
by user space tools like llvm-objdump etc. for BPF target.
This patch also contains tests to verify generated
.BTF and .BTF.ext sections for all supported types, func_info
and line_info subsections. The patch is also tested
against linux kernel bpf sample tests and selftests.
Signed-off-by: Yonghong Song <yhs@fb.com>
Differential Revision: https://reviews.llvm.org/D53736
llvm-svn: 347999
Packing the flags into one bitcode word will save effort in
adding new flags in the future.
Differential Revision: https://reviews.llvm.org/D54755
llvm-svn: 347806
When you have a member function with a ref-qualifier, for example:
struct Foo {
void Func() &;
void Func2() &&;
};
clang-cl was not emitting this information. Doing so is a bit
awkward, because it's not a property of the LF_MFUNCTION type, which
is what you'd expect. Instead, it's a property of the this pointer
which is actually an LF_POINTER. This record has an attributes
bitmask on it, and our handling of this bitmask was all wrong. We
had some parts of the bitmask defined incorrectly, but importantly
for this bug, we didn't know about these extra 2 bits that represent
the ref qualifier at all.
Differential Revision: https://reviews.llvm.org/D54667
llvm-svn: 347354
This is for compatibility with MSVC, which also marks this pointers
as being const-qualified.
Fixes llvm.org/pr36526
Differential Revision: https://reviews.llvm.org/D54736
llvm-svn: 347353
PointerAttributes is a bitwise-or of several other fields, each of
which is already printed on its own line with a better explanation.
So this doesn't really help much.
llvm-svn: 347275
Summary:
Experience has shown that the functionality is useful. It makes linking
optimized clang with debug info for me a lot faster, 20s to 13s. The
type merging phase of PDB writing goes from 10s to 3s.
This removes the LLVM cl::opt and replaces it with a metadata flag.
After this change, users can do the following to use ghash:
- add -gcodeview-ghash to compiler flags
- replace /DEBUG with /DEBUG:GHASH in linker flags
Reviewers: zturner, hans, thakis, takuto.ikuta
Subscribers: aprantl, hiraditya, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D54370
llvm-svn: 347072
The machine scheduler currently biases register copies to/from
physical registers to be closer to their point of use / def to
minimize their live ranges. This change extends this to also physical
register assignments from immediate values.
This causes a reduction in reduction in overall register pressure and
minor reduction in spills and indirectly fixes an out-of-registers
assertion (PR39391).
Most test changes are from minor instruction reorderings and register
name selection changes and direct consequences of that.
Reviewers: MatzeB, qcolombet, myatsina, pcc
Subscribers: nemanjai, jvesely, nhaehnle, eraman, hiraditya,
javed.absar, arphaman, jfb, jsji, llvm-commits
Differential Revision: https://reviews.llvm.org/D54218
llvm-svn: 346894
Summary:
The comment refers to the field as "Kind:". However, in gdb,
https://sourceware.org/gdb//onlinedocs/gdb/Index-Section-Format.html names it "attributes",
gdb/dwarf2read.c:dw2_symtab_iter_next refers to the whole value as "cu_index_and_attrs"
Change it to `Attributes:` for consistency.
Reviewers: dblaikie
Reviewed By: dblaikie
Subscribers: aprantl, JDevlieghere, arphaman, llvm-commits
Differential Revision: https://reviews.llvm.org/D54480
llvm-svn: 346790
Summary:
Ranges base address specifiers can save a lot of object size in
relocation records especially in optimized builds.
For an optimized self-host build of Clang with split DWARF and debug
info compression in object files, but uncompressed debug info in the
executable, this change produces about 18% smaller object files and 6%
larger executable.
While it would've been nice to turn this on by default, gold's 32 bit
gdb-index support crashes on this input & I don't think there's any
perfect heuristic to implement solely in LLVM that would suffice - so
we'll need a flag one way or another (also possible people might want to
aggressively optimized for executable size that contains debug info
(even with compression this would still come at some cost to executable
size)) - so let's plumb it through.
Differential Revision: https://reviews.llvm.org/D54242
llvm-svn: 346788
Summary: The debug_info_offset values in .debug_{,gnu_}pub{name,types} may be relocated. Change it to DWARFSection so that we can get relocated values.
Reviewers: ruiu, dblaikie, grimar, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: aprantl, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D54375
llvm-svn: 346615
This reverts commit r345972. Need to update the description + possibly
to update the patch itself after discussion with Eric Christofer.
llvm-svn: 346508
Use MachineFrameInfo's OffsetAdjustment field to pass this information
from the target to CodeViewDebug.cpp. The X86 backend doesn't use it for
any other purpose.
This fixes PR38857 in the case where there is a non-aligned quantity of
CSRs and a non-aligned quantity of locals.
llvm-svn: 346062
Adding functionality to the DWARF verifier for DWARF v5 strx* forms which
index into the string offsets table.
Differential Revision: https://reviews.llvm.org/D54049
llvm-svn: 346061
Summary:
If the output of debug directives only is requested, we should drop
emission of ',debug' option from the target directive. Required for
supporting of nvprof profiler.
Reviewers: probinson, echristo, dblaikie
Subscribers: Hahnfeld, jholewinski, llvm-commits, JDevlieghere, aprantl
Differential Revision: https://reviews.llvm.org/D46061
llvm-svn: 345972
These tests are meant to test dwarf emission (or prolog/epilogue
generation) so we can convert them to .mir and only run the relevant
part of the pipeline.
This way they become independent of changes in earlier passes such as my
planned changes to RegAllocFast.
llvm-svn: 345919
The TypeIndex used by cl.exe is 0x103, which indicates a SimpleTypeMode
of NearPointer (note the absence of the bitness, normally pointers use a
mode of NearPointer32 or NearPointer64) and a SimpleTypeKind of void.
So this is basically a void*, but without a specified size, which makes
sense given how std::nullptr_t is defined.
clang-cl was actually not emitting *anything* for this. Instead, when we
encountered std::nullptr_t in a DIType, we would actually just emit a
TypeIndex of 0, which is obviously wrong.
std::nullptr_t in DWARF is represented as a DW_TAG_unspecified_type with
a name of "decltype(nullptr)", so we add that logic along with a test,
as well as an update to the dumping code so that we no longer print
void* when dumping 0x103 (which would previously treat Void/NearPointer
no differently than Void/NearPointer64).
Differential Revision: https://reviews.llvm.org/D53957
llvm-svn: 345811
The debug-use flag must be set exactly for uses on DBG_VALUEs. This is
so obvious that it can be trivially inferred while parsing. This will
reduce noise when printing while omitting an information that has little
value to the user.
The parser will keep recognizing the flag for compatibility with old
`.mir` files.
Differential Revision: https://reviews.llvm.org/D53903
llvm-svn: 345671
- Relex hard coded registers and stack frame sizes
- Some test cleanups
- Change phi-dbg.ll to match on mir output after phi elimination instead
of going through the whole codegen pipeline.
This is in preparation for https://reviews.llvm.org/D52010
I'm committing all the test changes upfront that work before and after
independently.
llvm-svn: 345532
The machine verifier was disabled for x86 by default. There are now only
9 tests failing, compared to what previously was between 20 and 30.
This is a good opportunity to file bugs for all the remaining issues,
then explicitly disable the failing tests and enabling the machine
verifier by default.
This allows us to avoid adding new tests that break the verifier.
PR27481
llvm-svn: 345513
Summary:
If the instruction in the eliminateFrameIndex function is a DBG_VALUE
instruction, it requires special processing. The frame register is set
to VRFrame and the offset is based on the object offset.
The code is similar to the code used in
lib/CodeGen/PrologEpilogInserter.cpp.
Reviewers: tra
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D53657
llvm-svn: 345269
This makes the offsets larger (since they are further from the base
address) but those are in the .dwo - and allows removing addresses and
relocations from the .o file.
This could be built into the AddressPool more fundamentally, perhaps -
when you ask for an AddressPool entry you could say "or give me some
other entry and an offset I need to use" - though what to do about
situations where the first use of an address in a section is not the
earliest address in that section... is tricky.
At least with range addresses we can be fairly sure we've seen the
earliest address first because we see the start address for the
function.
llvm-svn: 345224
Summary:
If the target does not support `.asciz` and `.ascii` directives, the
strings are represented as bytes and each byte is placed on the new line
as a separate byte directive `.b8 <data>`. NVPTX target allows to
represent the vector of the data of the same type as a vector, where
values are separated using `,` symbol: `.b8 <data1>,<data2>,...`. This
allows to reduce the size of the final PTX file. Ptxas tool includes ptx
files into the resulting binary object, so reducing the size of the PTX
file is important.
Reviewers: tra, jlebar, echristo
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D45822
llvm-svn: 345142
This teaches llvm-dwarfdump to dump the content of .debug_loclists sections.
It converts the DWARFDebugLocDWO class to DWARFDebugLoclists,
teaches llvm-dwarfdump about .debug_loclists section and
adds the implementation for parsing the DW_LLE_offset_pair entries.
Differential revision: https://reviews.llvm.org/D53364
llvm-svn: 344895
Using a base address specifier even for a single-element range is a size
win for object files (7 words versus 8 words - more significant savings
if the debug info is compressed (since it's 3 words of uncompressable
reloc + 4 compressable words compared to 6 uncompressable reloc + 2
compressable words) - does trade off executable size increase though.
llvm-svn: 344841
Putting addresses in the address pool, even with non-fission, can reduce
relocations - reusing the addresses from debug_info and debug_rnglists
(the latter coming soon)
llvm-svn: 344834
Considers the index when extracting location lists from a .dwp file.
Majority of the patch by David Blaikie.
Reviewers: dblaikie
Differential revision: https://reviews.llvm.org/D53155
llvm-svn: 344807
When compiling static executable for micromips, CFI symbols
are incorrectly labeled as MICROMIPS, which cause
".eh_frame_hdr refers to overlapping FDEs." error.
This patch does not label CFI symbols as MICROMIPS, and FDEs do not
overlap anymore. This patch also exposes another bug, which is fixed
here: https://reviews.llvm.org/D52985
Differential Revision: https://reviews.llvm.org/D52987
llvm-svn: 344516
When compiling static executable for micromips, CFI symbols
are incorrectly labeled as MICROMIPS, which cause
".eh_frame_hdr refers to overlapping FDEs." error.
This patch does not label CFI symbols as MICROMIPS, and FDEs do not
overlap anymore. This patch also exposes another bug, which is fixed
here: https://reviews.llvm.org/D52985
Differential Revision: https://reviews.llvm.org/D52987
llvm-svn: 344511
Summary: We can fill in the command line and compiler path later if we want.
Reviewers: zturner
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D53179
llvm-svn: 344393
It originally triggered a stepping problem in the debugger, which could
be fixed by adjusting CodeGen/LexicalScopes.cpp however it seems we prefer
the previous behavior anyway.
See the discussion for details: http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20181008/593833.html
This reverts commit r343880.
This reverts commit r343874.
llvm-svn: 344318
When we're on the last bucket the computation is tricky.
We were failing when the last bucket contained multiple
matches. Added a new test for this.
llvm-svn: 344081
Hsiangkai Wang