Add tests which can catch the issue in 0ce723cb22
(If any function needs CFISection::EH, the module should use CFISection::EH).
Reviewed By: echristo
Differential Revision: https://reviews.llvm.org/D101339
This patch fixes a crash in LiveDebugVariables for inputs where a
DBG_VALUE_LIST had 64 or more debug operands. This was triggering an
assert, which was added under the assumption that only bad CodeGen would
result in such a limit being hit, but relatively simple source files
that result in these incredibly long debug values have been found, so
this assert has been changed to a condition that drops the debug value
if it is not met.
Differential Revision: https://reviews.llvm.org/D101373
https://reviews.llvm.org/D99400 set clang DefaultDebuggerTuning for AIX
to dbx. However, we still need to update the target default so that llc
and other tools will get the same default debuggertuning, and avoid
passing extra options in LTO.
Reviewed By: #powerpc, shchenz, dblaikie
Differential Revision: https://reviews.llvm.org/D101197
Previous build failures were caused by an error in bitcode reading and
writing for DIArgList metadata, which has been fixed in e5d844b587.
There were also some unnecessary asserts that were being triggered on
certain builds, which have been removed.
This reverts commit dad5caa59e.
This patch fixes an issue in which ConstantAsMetadata arguments to a
DIArglist, as well as the Constant values referenced by that metadata,
would not be always be emitted correctly into bitcode. This patch fixes
this issue firstly by searching for ConstantAsMetadata in DIArgLists
(previously we would only search for them when directly wrapped in
MetadataAsValue), and secondly by enumerating all of a DIArgList's
arguments directly prior to enumerating the DIArgList itself.
This patch also adds a number of asserts, and no longer treats the
arguments to a DIArgList as optional fields when reading/writing to
bitcode.
Differential Revision: https://reviews.llvm.org/D100572
This change adds debug information about whether PGO is being used or
not.
Microsoft performance tooling (e.g. xperf, WPA) uses this information to
show whether functions are optimized with PGO or not, as well as whether
PGO information is invalid.
This information is useful for validating whether training scenarios are
providing good coverage of real world scenarios, showing if profile data
is out of date, etc.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D99994
Value::replaceUsesOutsideBlock doesn't replace debug uses which leads to an
unnecessary reduction in variable location coverage. Fix this, add a unittest for
it, and add a regression test demonstrating the change through instcombine's
replacedSelectWithOperand.
Reviewed By: djtodoro
Differential Revision: https://reviews.llvm.org/D99169
D73568 removed the lit feature object-emission, because it was introduced for a
target which did not support the integrated assembler, and that target no longer
required the feature. XCore still does not support the integrated assembler,
so a build with XCore as the default target fails tests requiring
object-emission. This issue was not publicly visible because there was not a
buildbot for XCore as the default target. We fixed the failures downstream. We
now have builder clang-xcore-ubuntu-20-x64 on the staging buildmaster, which
shows the failures. We would like to make upstream build green.
Omit DebugInfo/Generic on XCore to avoid annotating 70 separate files.
Differential Revision: https://reviews.llvm.org/D98508
Value::replaceUsesOutsideBlock doesn't replace debug uses which leads to an
unnecessary reduction in variable location coverage. Fix this, add a unittest for
it, and add a regression test demonstrating the change through instcombine's
replacedSelectWithOperand.
Reviewed By: djtodoro
Differential Revision: https://reviews.llvm.org/D99169
Summary: Set the default DwarfInlinedStrings as inlined strings for DBX, due to DBX does not support .dwstr section for now.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D99933
Negative numbers are represented using DW_OP_consts along with signed representation
of the number as the argument.
Test case IR is generated using Fortran front-end.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D99273
This is needed for Fortran assumed shape arrays whose dimensions are
defined as,
- 'count' is taken from array descriptor passed as parameter by
caller, access from descriptor is defined by type DIExpression.
- 'lowerBound' is defined by callee.
The current alternate way represents using upperBound in place of
count, where upperBound is calculated in callee in a temp variable
using lowerBound and count
Representation with count (DIExpression) is not only clearer as
compared to upperBound (DIVariable) but it has another advantage that
variable count is accessed by being parameter has better chance of
survival at higher optimization level than upperBound being local
variable.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D99335
This commit adds debugging support for set types defined in languages
such as Pascal and Modula-2.
Patch by Peter McKinna!
Differential Revision: https://reviews.llvm.org/D76115
I think byval/sret and the others are close to being able to rip out
the code to support the missing type case. A lot of this code is
shared with inalloca, so catch this up to the others so that can
happen.
XCore default subtarget does not support 8-byte stack alignment. These failures
can be seen on builder clang-xcore-ubuntu-20-x64 on staging buildbot.
Differential Revision: https://reviews.llvm.org/D99092
Exclude AArch64 mapping symbols ($x and $d) for symtab symbolization as
it was done for ARM since D95916 tom bring bots back to green state.
This is implemented by setting SF_FormatSpecific such that
llvm-symbolizer will ignore them, and use this flag to re-implement
llvm-nm --special-syms option which make it work for both targets.
Differential Revision: https://reviews.llvm.org/D98803
On RISC-V, clang emits empty name symbols used for label differences. (In GCC the symbols are typically `.L0`)
After D95916, the empty name symbols can show up in llvm-symbolizer's symbolization output.
They have no names and thus not useful. Set `SF_FormatSpecific` so that llvm-symbolizer will ignore them.
`SF_FormatSpecific` is also used in LTO but that case should not matter.
Corresponding addr2line problem: https://sourceware.org/bugzilla/show_bug.cgi?id=27585
Reviewed By: luismarques
Differential Revision: https://reviews.llvm.org/D98669
Summary: This is a minor patch to add names for the debug line prologue, as a follow-up of D95998.
Reviewed By: dblaikie, ikudrin, shchenz
Differential Revision: https://reviews.llvm.org/D98383
This patch improves salvageDebugInfoImpl by allowing it to salvage arithmetic
operations with two or more non-const operands; this includes the GetElementPtr
instruction, and most Binary Operator instructions. These salvages produce
DIArgList locations and are only valid for dbg.values, as currently variadic
DIExpressions must use DW_OP_stack_value. This functionality is also only added
for salvageDebugInfoForDbgValues; other functions that directly call
salvageDebugInfoImpl (such as in ISel or Coroutine frame building) can be
updated in a later patch.
Differential Revision: https://reviews.llvm.org/D91722
This patch allows DBG_VALUE_LIST instructions to be emitted to DWARF with valid
DW_AT_locations. This change mainly affects DbgEntityHistoryCalculator, which
now tracks multiple registers per value, and DwarfDebug+DwarfExpression, which
can now emit multiple machine locations as part of a DWARF expression.
Differential Revision: https://reviews.llvm.org/D83495
This patch adds support for DBG_VALUE_LIST in the LiveDebugVariables pass. The
changes are mostly in computeIntervals, extendDef, and addDefsFromCopies; when
extending the def of a DBG_VALUE_LIST the live ranges of every used register
must be considered, and when such a def is killed by more than one of its used
registers being killed at the same time it is necessary to find valid copies of
all of those registers to create a new def with.
The DebugVariableValue class has also been changed to reference multiple
location numbers instead of just one. This has been accomplished by using a
C-style array with a unique_ptr and an array length packed into 6 bits, to
minimize the size of the class (which must be kept low to be used with
IntervalMap). This may not be the most efficient solution possible, and should
be looked at if performance issues arise.
Differential Revision: https://reviews.llvm.org/D83895
This patch implements DBG_VALUE_LIST handling to the LiveDebugValues pass. This
is a substantial change, and makes a few fundamental changes to the existing
logic.
We still use the basic model of a VarLocMap that is indexed by a LocIndex, with
a VarLocSet (a CoalescingBitVector underneath) giving us efficient lookups of
existing variable locations for a given location type. The main change is that
the VarLocMap may contain a given VarLoc multiple times (once for each unique
location operand), so that a VarLoc can be looked up from any of the registers
that it uses. This means that each VarLoc has multiple corresponding LocIndexes;
to allow us to iterate through the set of VarLocs (previously we would iterate
through the VarLocSet), we now also maintain a single entry in the VarLocMap
that contains every VarLoc exactly once.
The VarLoc class itself is also changed; this change is much simpler,
refactoring out location-specific members into a MachineLocation class and
adding a vector of these locations.
Differential Revision: https://reviews.llvm.org/D83890
In some cases a broken or invalid debug info could cause a crash in DWARFUnit::getInlinedChainForAddress during parsing a chain of in-lined functions. This patch fixes this issue.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D98119
D81469 introduced a check to error on CIE version different
than 1 for eh_frame, but older compilers mistakenly create binaries
with this version set to 3 for DWARF4 or 4 to DWARF5. Move the check
to dump time instead of eh_frame parse time, so we can be tolerant
with older binaries.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D97830
This patch adds a new metadata node, DIArgList, which contains a list of SSA
values. This node is in many ways similar in function to the existing
ValueAsMetadata node, with the difference being that it tracks a list instead of
a single value. Internally, it uses ValueAsMetadata to track the individual
values, but there is also a reasonable amount of DIArgList-specific
value-tracking logic on top of that. Similar to ValueAsMetadata, it is a special
case in parsing and printing due to the fact that it requires a function state
(as it may reference function-local values).
This patch should not result in any immediate functional change; it allows for
DIArgLists to be parsed and printed, but debug variable intrinsics do not yet
recognize them as a valid argument (outside of parsing).
Differential Revision: https://reviews.llvm.org/D88175
See original comment in 560ce2c70f
Baiscally the default seed value results in less collision, but changes the
iteration order, which matters for a few test cases.
Differential Revision: https://reviews.llvm.org/D97396
remove `Hi` `Lo` argument from `emitDwarfUnitLength`, so we
can make caller of emitDwarfUnitLength easier.
Reviewed By: MaskRay, dblaikie, ikudrin
Differential Revision: https://reviews.llvm.org/D96409
There is a trailing dot in text section name if it has prefix, don't add
repeated dot when connect text section name and symbol name.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D96327
As discussed on the RFC [0], I am sharing the set of patches that
enables checking of original Debug Info metadata preservation in
optimizations. The proof-of-concept/proposal can be found at [1].
The implementation from the [1] was full of duplicated code,
so this set of patches tries to merge this approach into the existing
debugify utility.
For example, the utility pass in the original-debuginfo-check
mode could be invoked as follows:
$ opt -verify-debuginfo-preserve -pass-to-test sample.ll
Since this is very initial stage of the implementation,
there is a space for improvements such as:
- Add support for the new pass manager
- Add support for metadata other than DILocations and DISubprograms
[0] https://groups.google.com/forum/#!msg/llvm-dev/QOyF-38YPlE/G213uiuwCAAJ
[1] https://github.com/djolertrk/llvm-di-checker
Differential Revision: https://reviews.llvm.org/D82545
The test that was failing is now forced to use the old PM.
As discussed on the RFC [0], I am sharing the set of patches that
enables checking of original Debug Info metadata preservation in
optimizations. The proof-of-concept/proposal can be found at [1].
The implementation from the [1] was full of duplicated code,
so this set of patches tries to merge this approach into the existing
debugify utility.
For example, the utility pass in the original-debuginfo-check
mode could be invoked as follows:
$ opt -verify-debuginfo-preserve -pass-to-test sample.ll
Since this is very initial stage of the implementation,
there is a space for improvements such as:
- Add support for the new pass manager
- Add support for metadata other than DILocations and DISubprograms
[0] https://groups.google.com/forum/#!msg/llvm-dev/QOyF-38YPlE/G213uiuwCAAJ
[1] https://github.com/djolertrk/llvm-di-checker
Differential Revision: https://reviews.llvm.org/D82545
Separate the LoZ ELF calling convention in tablegen.
This will make it easier to add the z/OS ABI in future patches.
Reviewed By: uweigand
Differential Revision: https://reviews.llvm.org/D96867
This allows the option to affect the LTO output. Module::Max helps to
generate debug info for all modules in the same format.
Differential Revision: https://reviews.llvm.org/D96597
Basic block sections enables function sections implicitly, this is not needed
and is inefficient with "=list" option.
We had basic block sections enable function sections implicitly in clang. This
is particularly inefficient with "=list" option as it places functions that do
not have any basic block sections in separate sections. This causes unnecessary
object file overhead for large applications.
This patch disables this implicit behavior. It only creates function sections
for those functions that require basic block sections.
Further, there was an inconistent behavior with llc as llc was not turning on
function sections by default. This patch makes llc and clang consistent and
tests are added to check the new behavior.
This is the first of two patches and this adds functionality in LLVM to
create a new section for the entry block if function sections is not
enabled.
Differential Revision: https://reviews.llvm.org/D93876
This patch enables AsmPrinter support for complex expression with
entry values. It shouldn't AsmPrinter's call whether these are safe or
not but the pass who introduces the DW_OP_LLVM_entry_value. This patch
on its own has no effect on clang.
Differential Revision: https://reviews.llvm.org/D96559
Their names don't convey much information, so they should be excluded.
The behavior matches addr2line.
Differential Revision: https://reviews.llvm.org/D96617
Before d08bd13ac8, only `SymbolRef::ST_Function`
symbols were used for .symtab symbolization. That commit added a `"DATA"` mode
to llvm-symbolizer which used `SymbolRef::ST_Data` symbols for symbolization.
Since function and data symbols have different addresses, we don't need to
differentiate the two modes. This patches unifies the two modes to simplify
code.
`"DATA"` is used by `compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cpp`.
`check-hwasan` and `check-tsan` have runtime tests.
Differential Revision: https://reviews.llvm.org/D96322
The ELF spec says:
> STT_FILE: Conventionally, the symbol's name gives the name of the source file associated with the object file. A file symbol has STB_LOCAL binding, its section index is SHN_ABS, and it precedes the other STB_LOCAL symbols for the file, if it is present.
For a local symbol, the preceding STT_FILE symbol is almost always in the same
file[1]. GNU addr2line uses this heuristic to retrieve the filename associated
with a local symbol (e.g. internal linkage functions in C/C++).
GNU addr2line can assign STT_FILE filename to a non-local symbol, too, but the trick
only works if no regular symbol precede STT_FILE. This patch does not implement this corner case
(not useful for most executables which have more than one files).
In case of filename mismatch between .debug_line & .symtab, arbitrarily make .debug_line win.
[1]: LLD does not synthesize STT_FILE symbols
(https://bugs.llvm.org/show_bug.cgi?id=48023 see also
https://sourceware.org/bugzilla/show_bug.cgi?id=26822). An assembly file
without `.file` directives can cause mis-attribution. This is an edge case.
Differential Revision: https://reviews.llvm.org/D95927
Originally landed in ddc2f1e3fb and reverted in d32deaab4d because of
a Generic test objecting. That was fixed up in 013613964f. Original
landing commit message follows:
[DWARF] Location-less inlined variables should not have DW_TAG_variable
Discussed in this thread:
https://lists.llvm.org/pipermail/llvm-dev/2021-January/148139.html
DwarfDebug::collectEntityInfo accidentally distinguishes between variable
locations that never have a location specified, and variable locations that
have an empty location specified. The latter leads to the creation of an
empty variable referring to the abstract origin.
Fix this by seeking a non-empty location before producing a concrete
entity, to guarantee a DW_AT_location will be produced. Other loops in
collectEntityInfo and endFunctionImpl take care of examining the
retainedNodes collection and ensuring optimised-out variables are created.
Differential Revision: https://reviews.llvm.org/D95617
Was e05c10380c, reverted in d7d0b17de7, see D95617 for details. I've
added "arm64" to the XFail list (as well as aarch64), will follow up on
the mailing list about whether there's anything else to be done.
This reverts commit 4fd29e4fd3.
There's a report in D95617 that this is failing on what (I think?) is an
aarch64 bot, which should be covered by the XFail list... reverting this
follow-up and the base patch until I work out what's wrong here.
In assembly files, omitting `.type foo,@function` is common. Such functions have
type `STT_NOTYPE` and llvm-symbolizer reports `??` for them.
An ifunc symbol usually has an associated resolver symbol which is defined at
the same address. Returning either one is fine for symbolization. The resolver
symbol may not end up in the symbol table if (object file) `.L` is used (linked
image) .symtab is stripped while .dynsym is retained.
This patch allows ELF STT_NOTYPE/STT_GNU_IFUNC symbols for .symtab symbolization.
I have left TODO in the test files for an unimplemented STT_FILE heuristic.
Differential Revision: https://reviews.llvm.org/D95916
Maskray has reported a fault with .debug_gnu_pubnames in the comments on
D94976, caused by this patch, reverting to investigate.
This reverts commit 8998f58435.
In the LLVM-IR for this test, the inlined argument "b" in the "a" function
is optimized out on certain architectures, not on others. This hasn't been
reported as a test failure since 93faeecd8f and ff2073a51 because we would
create a variable that looks like this:
DW_TAG_formal_parameter
DW_AT_abstract_origin
With no further information (and no location). With D95617 however, we
stop emitting such variables.
Prior to landing D95617: make this test stricter by checking that the
variable mentioned above has a location. We have to accept that on certain
architectures this goes missing, so add those to the XFail list.
I've run a few experiments, and right now it looks likely only powerpc64
still drops the variable location.
Previously the code split the string at the first '<', which
incorrectly truncated names like `operator<`.
Differential Revision: https://reviews.llvm.org/D95893
This modified patch avoids redirecting the unit in which a subprogram is
created if type units are enabled -- DIEs were getting children allocated
from different units memory pools. Original commit message:
[DWARF] Create subprogram's DIE in DISubprogram's unit
This is a fix for PR48790. Over in D70350, subprogram DIEs were permitted
to be shared between CUs. However, the creation of a subprogram DIE can be
triggered early, from other CUs. The subprogram definition is then created
in one CU, and when the function is actually emitted children are attached
to the subprogram that expect to be in another CU. This breaks internal CU
references in the children.
Fix this by redirecting the creation of subprogram DIEs in
getOrCreateContextDIE to the CU specified by it's DISubprogram definition.
This ensures that the subprogram DIE is always created in the correct CU.
Differential Revision: https://reviews.llvm.org/D94976
Discussed in this thread:
https://lists.llvm.org/pipermail/llvm-dev/2021-January/148139.html
DwarfDebug::collectEntityInfo accidentally distinguishes between variable
locations that never have a location specified, and variable locations that
have an empty location specified. The latter leads to the creation of an
empty variable referring to the abstract origin.
Fix this by seeking a non-empty location before producing a concrete
entity, to guarantee a DW_AT_location will be produced. Other loops in
collectEntityInfo and endFunctionImpl take care of examining the
retainedNodes collection and ensuring optimised-out variables are created.
Differential Revision: https://reviews.llvm.org/D95617
On z/OS, the following error message is not matched correctly in lit tests.
```
EDC5129I No such file or directory.
```
This patch uses a lit config substitution to check for platform specific error messages.
Reviewed By: muiez, jhenderson
Differential Revision: https://reviews.llvm.org/D95246
This patch adds the ability to evaluate the state machine for CIE and FDE unwind objects and produce a UnwindTable with all UnwindRow objects needed to unwind registers. It will also dump the UnwindTable for each CIE and FDE when dumping DWARF .debug_frame or .eh_frame sections in llvm-dwarfdump or llvm-objdump. This allows users to see what the unwind rows actually look like for a given CIE or FDE instead of just seeing a list of opcodes.
This patch adds new classes: UnwindLocation, RegisterLocations, UnwindRow, and UnwindTable.
UnwindLocation is a class that describes how to unwind a register or Call Frame Address (CFA).
RegisterLocations is a class that tracks registers and their UnwindLocations. It gets populated when parsing the DWARF call frame instruction opcodes for a unwind row. The registers are mapped from their register numbers to the UnwindLocation in a map.
UnwindRow contains the result of evaluating a row of DWARF call frame instructions for the CIE, or a row from a FDE. The CIE can produce a set of initial instructions that each FDE that points to that CIE will use as the seed for the state machine when parsing FDE opcodes. A UnwindRow for a CIE will not have a valid address, whille a UnwindRow for a FDE will have a valid address.
The UnwindTable is a class that contains a sorted (by address) vector of UnwindRow objects and is the result of parsing all opcodes in a CIE, or FDE. Parsing a CIE should produce a UnwindTable with a single row. Parsing a FDE will produce a UnwindTable with one or more UnwindRow objects where all UnwindRow objects have valid addresses. The rows in the UnwindTable will be sorted from lowest Address to highest after parsing the state machine, or an error will be returned if the table isn't sorted. To parse a UnwindTable clients can use the following methods:
static Expected<UnwindTable> UnwindTable::create(const CIE *Cie);
static Expected<UnwindTable> UnwindTable::create(const FDE *Fde);
A valid table will be returned if the DWARF call frame instruction opcodes have no encoding errors. There are a few things that can go wrong during the evaluation of the state machine and these create functions will catch and return them.
Differential Revision: https://reviews.llvm.org/D89845
This reverts commit ef0dcb5063.
This change is causing a lot of compiler crashes inside, sorry I don't have a
small repro/stacktrace with symbols to share right now.
Differential Revision: https://reviews.llvm.org/D95622
Experimental, using non-existent DWARF support to use an expr for the
location involving an addr_index (to compute address + offset so
addresses can be reused in more places).
The global variable debug info had to be deferred until the end of the
module (so bss variables would all be emitted first - so their labels
would have the relevant section). Non-bss variables seemed to not have
their label assigned to a section even at the end of the module, so I
didn't know what to do there.
Also, the hashing code is broken - doesn't know how to hash these
expressions (& isn't hashing anything inside subprograms, which seems
problematic), so for test purposes this change just skips the hash
computation. (GCC's actually overly sensitive in its hash function, it
seems - I'm forgetting the specific case right now - anyway, we might
want to just use the frontend-known file hash and give up on optimistic
.dwo/.dwp reuse)
This is a fix for PR48790. Over in D70350, subprogram DIEs were permitted
to be shared between CUs. However, the creation of a subprogram DIE can be
triggered early, from other CUs. The subprogram definition is then created
in one CU, and when the function is actually emitted children are attached
to the subprogram that expect to be in another CU. This breaks internal CU
references in the children.
Fix this by redirecting the creation of subprogram DIEs in
getOrCreateContextDIE to the CU specified by it's DISubprogram definition.
This ensures that the subprogram DIE is always created in the correct CU.
Differential Revision: https://reviews.llvm.org/D94976
This moves SinkIntoLoop from MachineLICM to MachineSink. The motivation for
this work is that hoisting is a canonicalisation transformation, but we do not
really have a good story to sink instructions back if that is better, e.g. to
reduce live-ranges, register pressure and spilling. This has been discussed a
few times on the list, the latest thread is:
https://lists.llvm.org/pipermail/llvm-dev/2020-December/147184.html
There it was pointed out that we have the LoopSink IR pass, but that works on
IR, lacks register pressure informatiom, and is focused on profile guided
optimisations, and then we have MachineLICM and MachineSink that both perform
sinking. MachineLICM is more about hoisting and CSE'ing of hoisted
instructions. It also contained a very incomplete and disabled-by-default
SinkIntoLoop feature, which we now move to MachineSink.
Getting loop-sinking to do something useful is going to be at least a 3-step
approach:
1) This is just moving the code and is almost a NFC, but contains a bug fix.
This uses helper function `isLoopInvariant` that was factored out in D94082 and
added to MachineLoop.
2) A first functional change to make loop-sink a little bit less restrictive,
which it really is at the moment, is the change in D94308. This lets it do
more (alias) analysis using functions in MachineSink, making it a bit more
powerful. Nothing changes much: still off by default. But it shows that
MachineSink is a better home for this, and it starts using its functionality
like `hasStoreBetween`, and in the next step we can use `isProfitableToSinkTo`.
3) This is the going to be he interesting step: decision making when and how
many instructions to sink. This will be driven by the register pressure, and
deciding if reducing live-ranges and loop sinking will help in better
performance.
4) Once we are happy with 3), this should be enabled by default, that should be
the end goal of this exercise.
Differential Revision: https://reviews.llvm.org/D93694
In MipsDelaySlotFiller, when replacing old call-branch with
the compact branch instruction, an assertion is caused by erasing
the old call with unhandled CSInfo.
The problem was reported in PR48695.
This patch fixes it, by moving call site info from the old call
instruction to its replace.
Patch by Nikola Tesic
Differential revision: https://reviews.llvm.org/D94685
On z/OS, the following error message is not matched correctly in lit tests. This patch updates the CHECK expression to match successfully.
```
EDC5129I No such file or directory.
```
Reviewed By: muiez
Differential Revision: https://reviews.llvm.org/D94239
New dwarf operator DW_OP_LLVM_implicit_pointer is introduced (present only in LLVM IR)
This operator is required as it is different than DWARF operator
DW_OP_implicit_pointer in representation and specification (number
and types of operands) and later can not be used as multiple level.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D84113
Local values are constants or addresses that can't be folded into
the instruction that uses them. FastISel materializes these in a
"local value" area that always dominates the current insertion
point, to try to avoid materializing these values more than once
(per block).
https://reviews.llvm.org/D43093 added code to sink these local
value instructions to their first use, which has two beneficial
effects. One, it is likely to avoid some unnecessary spills and
reloads; two, it allows us to attach the debug location of the
user to the local value instruction. The latter effect can
improve the debugging experience for debuggers with a "set next
statement" feature, such as the Visual Studio debugger and PS4
debugger, because instructions to set up constants for a given
statement will be associated with the appropriate source line.
There are also some constants (primarily addresses) that could be
produced by no-op casts or GEP instructions; the main difference
from "local value" instructions is that these are values from
separate IR instructions, and therefore could have multiple users
across multiple basic blocks. D43093 avoided sinking these, even
though they were emitted to the same "local value" area as the
other instructions. The patch comment for D43093 states:
Local values may also be used by no-op casts, which adds the
register to the RegFixups table. Without reversing the RegFixups
map direction, we don't have enough information to sink these
instructions.
This patch undoes most of D43093, and instead flushes the local
value map after(*) every IR instruction, using that instruction's
debug location. This avoids sometimes incorrect locations used
previously, and emits instructions in a more natural order.
In addition, constants materialized due to PHI instructions are
not assigned a debug location immediately; instead, when the
local value map is flushed, if the first local value instruction
has no debug location, it is given the same location as the
first non-local-value-map instruction. This prevents PHIs
from introducing unattributed instructions, which would either
be implicitly attributed to the location for the preceding IR
instruction, or given line 0 if they are at the beginning of
a machine basic block. Neither of those consequences is good
for debugging.
This does mean materialized values are not re-used across IR
instruction boundaries; however, only about 5% of those values
were reused in an experimental self-build of clang.
(*) Actually, just prior to the next instruction. It seems like
it would be cleaner the other way, but I was having trouble
getting that to work.
This reapplies commits cf1c774d and dc35368c, and adds the
modification to PHI handling, which should avoid problems
with debugging under gdb.
Differential Revision: https://reviews.llvm.org/D91734
This adds a new test checking llvm-symbolizer with an object built with basic block sections.
Build a object with -fbasic-block-sections and reorder the basic blocks to be
non-contiguous. Then check if llvm-symbolizer correctly reports the symbolized
addresses. Included the source to build the object with command lines.
Differential Revision: https://reviews.llvm.org/D91678
Build a object with -fbasic-block-sections and reorder the basic blocks to be
non-contiguous. Then check if llvm-symbolizer correctly reports the symbolized
addresses. Included the source to build the object with command lines.
Differential Revision: https://reviews.llvm.org/D91678
Given the ability provided by DWARFv5 rnglists to reuse addresses in the
address pool, it can be advantageous to object file size to use range
encodings even when the range could be described by a direct low/high
pc.
Add a flag to allow enabling this in DWARFv5 for the purpose of
experimentation/data gathering.
It might be that it makes sense to enable this functionality by default
for DWARFv5 + Split DWARF at least, where the tradeoff/desire to
optimize for .o file size is more explicit and .o bytes are higher
priority than .dwo bytes.
Every basic block section symbol created by -fbasic-block-sections will contain
".__part." to know that this symbol corresponds to a basic block fragment of
the function.
This patch solves two problems:
a) Like D89617, we want function symbols with suffixes to be properly qualified
so that external tools like profile aggregators know exactly what this
symbol corresponds to.
b) The current basic block naming just adds a ".N" to the symbol name where N is
some integer. This collides with how clang creates __cxx_global_var_init.N.
clang creates these symbol names to call constructor functions and basic
block symbol naming should not use the same style.
Fixed all the test cases and added an extra test for __cxx_global_var_init
breakage.
Differential Revision: https://reviews.llvm.org/D93082
Currently using DW_OP_implicit_value in fragments produces invalid DWARF
expressions. (Such a case can occur in complex floats, for example.)
This problem manifests itself as a missing DW_OP_piece operation after
the last fragment. This happens because the function for printing
constant float value skips printing the accompanying DWARF expression,
as that would also print DW_OP_stack_value (which is not desirable in
this case). However, this also results in DW_OP_piece being skipped.
The reason that DW_OP_piece is missing only for the last piece is that
the act of printing the next fragment corrects this. However, it does
that for the wrong reason -- the code emitting this DW_OP_piece thinks
that the previous fragment was missing, and so it thinks that it needs
to skip over it in order to be able to print itself.
In a simple scenario this works out, but it's likely that in a more
complex setup (where some pieces are in fact missing), this logic would
go badly wrong. In a simple setup gdb also seems to not mind the fact
that the DW_OP_piece is missing, but it would also likely not handle
more complex use cases.
For this reason, this patch disables the usage of DW_OP_implicit_value
in the frament scenario (we will use DW_OP_const*** instead), until we
figure out the right way to deal with this. This guarantees that we
produce valid expressions, and gdb can handle both kinds of inputs
anyway.
Differential Revision: https://reviews.llvm.org/D92013
The main change is to add a 'IsDecl' field to DIModule so
that when IsDecl is set to true, the debug info entry generated
for the module would be marked as a declaration. That way, the debugger
would look up the definition of the module in the gloabl scope.
Please see the comments in llvm/test/DebugInfo/X86/dimodule.ll
for what the debug info entries would look like.
Differential Revision: https://reviews.llvm.org/D93462
Use SCEV to salvage additional @llvm.dbg.value that have turned into
referencing undef after transformation (and traditional
salvageDebugInfo). Before rewrite (but after introduction of new
induction variables) use SCEV to compute an equivalent set of values for
each @llvm.dbg.value in the loop body (among the loop header PHI-nodes).
After rewrite (and dead PHI elimination) update those @llvm.dbg.value
now referencing undef by picking a remaining value from its equivalence
set. Allow match with offset by inserting compensation code in the
DIExpression.
Fixes : PR38815
Differential Revision: https://reviews.llvm.org/D87494
If a function parameter is marked as "undef", prevent creation
of CallSiteInfo for that parameter.
Without this patch, the parameter's call_site_value would be incorrect.
The incorrect call_value case reported in PR39716,
addressed in D85111.
Patch by Nikola Tesic
Differential revision: https://reviews.llvm.org/D92471
This patch makes DWARF writer emit DW_AT_string_length using
the stringLengthExp operand of DIStringType.
This is part of the effort to add debug info support for
Fortran deferred length strings.
Also updated the tests to exercise the change.
Differential Revision: https://reviews.llvm.org/D92412
Allow sections to be placed into COMDAT groups, in addtion to functions and data
segments.
Also make section symbols unnamed, which allows sections with identical names
(section names are independent of their section symbols, but previously we
gave the symbols the same name as their sections, which results in collisions
when sections are identically-named).
Differential Revision: https://reviews.llvm.org/D92691
They are currently implicit because TargetMachine::shouldAssumeDSOLocal implies
dso_local.
For such function declarations, clang -fno-pic emits the dso_local specifier.
Adding explicit dso_local makes these tests align with the clang behavior and
helps implementing an option to use GOT indirection when taking the address of a
function symbol in -fno-pic (to avoid a canonical PLT entry (SHN_UNDEF with
non-zero st_value)).
They are currently implicit because TargetMachine::shouldAssumeDSOLocal implies
dso_local.
For external data, clang -fno-pic emits the dso_local specifier for ELF and
non-MinGW COFF. Adding explicit dso_local makes these tests in align with the
clang behavior and helps implementing an option to use GOT indirection for
external data access in -fno-pic mode (to avoid copy relocations).
This reverts commit cf1c774d6a.
This change caused several regressions in the gdb test suite - at least
a sample of which was due to line zero instructions making breakpoints
un-lined. I think they're worth investigating/understanding more (&
possibly addressing) before moving forward with this change.
Revert "[FastISel] NFC: Clean up unnecessary bookkeeping"
This reverts commit 3fd39d3694.
Revert "[FastISel] NFC: Remove obsolete -fast-isel-sink-local-values option"
This reverts commit a474657e30.
Revert "Remove static function unused after cf1c774."
This reverts commit dc35368ccf.
Revert "[lldb] Fix TestThreadStepOut.py after "Flush local value map on every instruction""
This reverts commit 53a14a47ee.
A crash/assertion failure in the greedy register allocator was tracked
down to a debug instr being passed to LiveIntervals::getInstructionIndex.
Normally this should not occur as debug instructions are collected and
removed by LiveDebugVariables before RA, and reinserted afterwards.
However, when a function has no debug info, LiveDebugVariables simply
strips any debug values that are present as they're not needed (this
situation will occur when a function with debug info is inlined into a
nodebug function). The problem is, it only removes DBG_VALUE instructions,
leaving DBG_LABELs (the cause of the crash).
This patch updates the LiveDebugVariables nodebug path to remove all debug
instructions. The test case verifies that DBG_VALUE/DBG_LABEL instructions
are present, and that they are stripped.
When -experimental-debug-variable-locations is enabled, certain variable
locations are represented by DBG_INSTR_REF instead of DBG_VALUE. The test
case verifies that a DBG_INSTR_REF is emitted by the option, and that it
is also stripped.
Differential Revision: https://reviews.llvm.org/D92127
In https://reviews.llvm.org/D89072 I added static const data members
to the debug subsection for globals. It skipped emitting an S_CONSTANT if it
didn't have a value, which meant the subsection could be empty.
This patch fixes the empty subsection issue.
Differential Revision: https://reviews.llvm.org/D92049
Local values are constants or addresses that can't be folded into
the instruction that uses them. FastISel materializes these in a
"local value" area that always dominates the current insertion
point, to try to avoid materializing these values more than once
(per block).
https://reviews.llvm.org/D43093 added code to sink these local
value instructions to their first use, which has two beneficial
effects. One, it is likely to avoid some unnecessary spills and
reloads; two, it allows us to attach the debug location of the
user to the local value instruction. The latter effect can
improve the debugging experience for debuggers with a "set next
statement" feature, such as the Visual Studio debugger and PS4
debugger, because instructions to set up constants for a given
statement will be associated with the appropriate source line.
There are also some constants (primarily addresses) that could be
produced by no-op casts or GEP instructions; the main difference
from "local value" instructions is that these are values from
separate IR instructions, and therefore could have multiple users
across multiple basic blocks. D43093 avoided sinking these, even
though they were emitted to the same "local value" area as the
other instructions. The patch comment for D43093 states:
Local values may also be used by no-op casts, which adds the
register to the RegFixups table. Without reversing the RegFixups
map direction, we don't have enough information to sink these
instructions.
This patch undoes most of D43093, and instead flushes the local
value map after(*) every IR instruction, using that instruction's
debug location. This avoids sometimes incorrect locations used
previously, and emits instructions in a more natural order.
This does mean materialized values are not re-used across IR
instruction boundaries; however, only about 5% of those values
were reused in an experimental self-build of clang.
(*) Actually, just prior to the next instruction. It seems like
it would be cleaner the other way, but I was having trouble
getting that to work.
Differential Revision: https://reviews.llvm.org/D91734
This patch moves the selection of the style used to emit the numbers
(DW_OP_implicit_value vs. DW_OP_const+DW_OP_stack_value) into
DwarfExpression::addUnsignedConstant. This logic is not FP-specific, and
it will be needed for large integers too.
The refactor also makes DW_OP_implicit_value (DW_OP_stack_value worked
already) be used for floating point constants other than float and
double, so I've added a _Float16 test for it.
Split off from D90916.
Differential Revision: https://reviews.llvm.org/D91058
With a function pass manager, it would insert debuginfo metadata before
getting to function passes while processing the pass manager, causing
debugify to skip while running the function passes.
Skip special passes + verifier + printing passes. Compared to the legacy
implementation of -debugify-each, this additionally skips verifier
passes. Probably no need to update the legacy version since it will be
obsolete soon.
This fixes 2 instcombine tests using -debugify-each under NPM.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D91558
Extend the existing basic block sections debug info test to check for the correctness of the generated line table.
Differential Revision: https://reviews.llvm.org/D90989
Imagine we have a YAML declaration of few sections: `foo1`, `<unnamed 2>`, `foo3`, `foo4`.
To put them into segment we can do (1*):
```
Sections:
- Section: foo1
- Section: foo4
```
or we can use (2*):
```
Sections:
- Section: foo1
- Section: foo3
- Section: foo4
```
or (3*) :
```
Sections:
- Section: foo1
## "(index 2)" here is a name that we automatically created for a unnamed section.
- Section: (index 2)
- Section: foo3
- Section: foo4
```
It looks really confusing that we don't have to list all of sections.
At first I've tried to make this rule stricter and report an error when there is a gap
(i.e. when a section is included into segment, but not listed explicitly).
This did not work perfect, because such approach conflicts with unnamed sections/fills (see (3*)).
This patch drops "Sections" key and introduces 2 keys instead: `FirstSec` and `LastSec`.
Both are optional.
Differential revision: https://reviews.llvm.org/D90458
This caused an explosion in ICF times during linking on Windows when libfuzzer
instrumentation is enabled. For a small binary we see ICF time go from ~0 to
~10 s. For a large binary it goes from ~1 s to forevert (I gave up after 30
minutes).
See comment on the code review.
> If we are going to write handler data (that is written as variable
> length data following after the unwind info in .xdata), we need to
> emit the handler data immediately, but for cases where no such
> info is going to be written, skip emitting it right away. (Unwind
> info for all remaining functions that hasn't gotten it emitted
> directly is emitted at the end.)
>
> This does slightly change the ordering of sections (triggering a
> bunch of updates to DebugInfo/COFF tests), but the change should be
> benign.
>
> This also matches GCC's assembly output, which doesn't output
> .seh_handlerdata unless it actually is needed.
>
> For ARM64, the unwind info can be packed into the runtime function
> entry itself (leaving no data in the .xdata section at all), but
> that can only be done if there's no follow-on data in the .xdata
> section. If emission of the unwind info is triggered via
> EmitWinEHHandlerData (or the .seh_handlerdata directive), which
> implicitly switches to the .xdata section, there's a chance of the
> caller wanting to pass further data there, so the packed format
> can't be used in that case.
>
> Differential Revision: https://reviews.llvm.org/D87448
This reverts commit 36c64af9d7.
Minimum amount of tests to cover (most) of the DISubprogram verifier
checks.
Reviewed By: vsk
Differential Revision: https://reviews.llvm.org/D90340
Change-Id: Icd25dac64f87f6dcf67ff3443eb4f95af18d05a8
Since Wasm comdat sections work similarly to ELF, we can use that mechanism
to eliminate duplicate dwarf type information in the same way.
Differential Revision: https://reviews.llvm.org/D88603
We used to only emit static const data members in CodeView as
S_CONSTANTS when they were used; this patch makes it so they are always emitted.
This changes CodeViewDebug.cpp to find the static const members from the
class debug info instead of creating DIGlobalVariables in the IR
whenever a static const data member is used.
Bug: https://bugs.llvm.org/show_bug.cgi?id=47580
Differential Revision: https://reviews.llvm.org/D89072
This reverts commit 504615353f.
This is needed to support fortran assumed rank arrays which
have runtime rank.
Summary:
Fortran assumed rank arrays have dynamic rank. DWARF TAG
DW_TAG_generic_subrange is needed to support that.
Testing:
unit test cases added (hand-written)
check llvm
check debug-info
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D89218
Fix an out-of-bounds shift in emitLegacyZExt by using a slightly more
complicated dwarf expression to create the zext mask.
This addresses a UBSan diagnostic seen when compiling compiler-rt
(llvm.org/PR47927).
rdar://70307714
Differential Revision: https://reviews.llvm.org/D89838
Since Wasm comdat sections work similarly to ELF, we can use that mechanism
to eliminate duplicate dwarf type information in the same way.
Differential Revision: https://reviews.llvm.org/D88603
We used to only emit static const data members in CodeView as
S_CONSTANTS when they were used; this patch makes it so they are always emitted.
I changed CodeViewDebug.cpp to find the static const members from the
class debug info instead of creating DIGlobalVariables in the IR
whenever a static const data member is used.
Bug: https://bugs.llvm.org/show_bug.cgi?id=47580
Differential Revision: https://reviews.llvm.org/D89072
This patch enables emitting DWARF `DW_OP_implicit_value` opcode when
tuning debug information for LLDB (`-debugger-tune=lldb`).
This will also propagate to Darwin platforms, since they use LLDB tuning
as a default.
rdar://67406059
Differential Revision: https://reviews.llvm.org/D90001
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Deciding where to place debugging instructions when normal instructions
sink between blocks is difficult -- see PR44117. Dealing with this with
instruction-referencing variable locations is simple: we just tolerate
DBG_INSTR_REFs referring to values that haven't been computed yet. This
patch adds support into InstrRefBasedLDV to record when a variable value
appears in the middle of a block, and should have a DBG_VALUE added when it
appears (a debug use before def).
While described simply, this relies heavily on the value-propagation
algorithm in InstrRefBasedLDV. The implementation doesn't attempt to verify
the location of a value unless something non-trivial occurs to merge
variable values in vlocJoin. This means that a variable with a value that
has no location can retain it across all control flow (including loops).
It's only when another debug instruction specifies a different variable
value that we have to check, and find there's no location.
This property means that if a machine value is defined in a block dominated
by a DBG_INSTR_REF that refers to it, all the successor blocks can
automatically find a location for that value (if it's not clobbered). Thus
in a sense, InstrRefBasedLDV is already supporting and implementing
use-before-defs. This patch allows us to specify a variable location in the
block where it's defined.
When loading live-in variable locations, TransferTracker currently discards
those where it can't find a location for the variable value. However, we
can tell from the machine value number whether the value is defined in this
block. If it is, add it to a set of use-before-def records. Then, once the
relevant instruction has been processed, emit a DBG_VALUE immediately after
it.
Differential Revision: https://reviews.llvm.org/D85775
Handle DBG_INSTR_REF instructions in LiveDebugValues, to determine and
propagate variable locations. The logic is fairly straight forwards:
Collect a map of debug-instruction-number to the machine value numbers
generated in the first walk through the function. When building the
variable value transfer function and we see a DBG_INSTR_REF, look up the
instruction it refers to, and pick the machine value number it generates,
That's it; the rest of LiveDebugValues continues as normal.
Awkwardly, there are two kinds of instruction numbering happening here: the
offset into the block (which is how machine value numbers are determined),
and the numbers that we label instructions with when generating
DBG_INSTR_REFs.
I've also restructured the TransferTracker redefVar code a little, to
separate some DBG_VALUE specific operations into its own method. The
changes around redefVar should be largely NFC, while allowing
DBG_INSTR_REFs to specify a value number rather than just a location.
Differential Revision: https://reviews.llvm.org/D85771
This patch copies @vsk's fix to instcombine from D85555 over to mem2reg. The
motivation and rationale are exactly the same: When mem2reg removes an alloca,
it erases the dbg.{addr,declare} instructions which refer to the alloca. It
would be better to instead remove all debug intrinsics which describe the
contents of the dead alloca, namely all dbg.value(<dead alloca>, ...,
DW_OP_deref)'s.
As far as I can tell, prior to D80264 these `dbg.value+deref`s would have been
silently dropped instead of being made `undef`, so we're just returning to
previous behaviour with these patches.
Testing:
`llvm-lit llvm/test` and `ninja check-clang` gave no unexpected failures. Added
3 tests, each of which covers a dbg.value deletion path in mem2reg:
mem2reg-promote-alloca-1.ll
mem2reg-promote-alloca-2.ll
mem2reg-promote-alloca-3.ll
The first is based on the dexter test inlining.c from D89543. This patch also
improves the debugging experience for loop.c from D89543, which suffers
similarly after arg promotion instead of inlining.
When switching the register debug operands to $noreg in
setupDebugValueUndef() also clear the sub-register indices for virtual
registers. This is done when marking DBG_VALUEs undef in other cases,
e.g. in LiveDebugVariables. I have not found any cases where leaving the
sub-register index causes any issues, and the indices would eventually
get dropped when LiveDebugVariables reinserted the undef DBG_VALUEs
after register scheduling, but if nothing else it looked a bit weird in
printouts to have sub-register indices on $noreg, and I don't think the
sub-register index holds any meaningful information at that point.
I have not been able to find any source-level reproducer for this with
an upstream target, so I have just added an instrumented machine-sink
test.
Reviewed By: djtodoro, jmorse
Differential Revision: https://reviews.llvm.org/D89941
Testing reveals that lldb and gdb have some problems with supporting
DW_OP_convert - gdb with Split DWARF tries to resolve the CU-relative
DIE offset relative to the skeleton DIE. lldb tries to treat the offset
as absolute, which judging by the llvm-dsymutil support for
DW_OP_convert, I guess works OK in MachO? (though probably llvm-dsymutil
is producing invalid DWARF by resolving the relative reference to an
absolute one?).
Specifically this disables DW_OP_convert usage in DWARFv5 if:
* Tuning for GDB and using Split DWARF
* Tuning for LLDB and not targeting MachO
Both FastRegAlloc and LiveDebugVariables/greedy need to cope with
DBG_INSTR_REFs. None of them actually need to take any action, other than
passing DBG_INSTR_REFs through: variable location information doesn't refer
to any registers at this stage.
LiveDebugVariables stashes the instruction information in a tuple, then
re-creates it later. This is only necessary as the register allocator
doesn't expect to see any debug instructions while it's working. No
equivalence classes or interval splitting is required at all!
No changes are needed for the fast register allocator, as it just ignores
debug instructions. The test added checks that both of them preserve
DBG_INSTR_REFs.
This also expands ScheduleDAGInstrs.cpp to treat DBG_INSTR_REFs the same as
DBG_VALUEs when rescheduling instructions around. The current movement of
DBG_VALUEs around is less than ideal, but it's not a regression to make
DBG_INSTR_REFs subject to the same movement.
Differential Revision: https://reviews.llvm.org/D85757
The instruction referencing work currently only works on X86, and all the
tests for it will be X86 based for the time being. Configure the whole
directory to be X86-only, seeing how I keep on landing tests that don't
have the correct REQUIRES lines.
This patch touches two optimizations, TwoAddressInstruction and X86's
FixupLEAs pass, both of which optimize by re-creating instructions. For
LEAs, various bits of arithmetic are better represented as LEAs on X86,
while TwoAddressInstruction sometimes converts instrs into three address
instructions if it's profitable.
For debug instruction referencing, both of these require substitutions to
be created -- the old instruction number must be pointed to the new
instruction number, as illustrated in the added test. If this isn't done,
any variable locations based on the optimized instruction are
conservatively dropped.
Differential Revision: https://reviews.llvm.org/D85756
Seems users have enough different uses of the symbolizer where they
might have unknown binaries and offsets such that "best effort" behavior
is all that's expected of llvm-symbolizer - so even erroring on unknown
executables and out of bounds offsets might not be suitable.
This reverts commit 1de0199748.
This reverts commit a7b209a6d4.
This reverts commit 338dd138ea.
Create the LLVM / CodeView register mappings for the 32-bit ARM Window targets.
Reviewed By: compnerd
Differential Revision: https://reviews.llvm.org/D89622
LLVM rejects DWARF operator DW_OP_over. This DWARF operator is needed
for Flang to support assumed rank array.
Summary:
Currently LLVM rejects DWARF operator DW_OP_over. Below error is
produced when llvm finds this operator.
[..]
invalid expression
!DIExpression(151, 20, 16, 48, 30, 35, 80, 34, 6)
warning: ignoring invalid debug info in over.ll
[..]
There were some parts missing in support of this operator, which are
now completed.
Testing
-added a unit testcase
-check-debuginfo
-check-llvm
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D89208
Add a table recording "substitutions" between pairs of <instruction,
operand> numbers, from old pairs to new pairs. Post-isel optimizations are
able to record the outcome of an optimization in this way. For example, if
there were a divide instruction that generated the quotient and remainder,
and it were replaced by one that only generated the quotient:
$rax, $rcx = DIV-AND-REMAINDER $rdx, $rsi, debug-instr-num 1
DBG_INSTR_REF 1, 0
DBG_INSTR_REF 1, 1
Became:
$rax = DIV $rdx, $rsi, debug-instr-num 2
DBG_INSTR_REF 1, 0
DBG_INSTR_REF 1, 1
We could enter a substitution from <1, 0> to <2, 0>, and no substitution
for <1, 1> as it's no longer generated.
This approach means that if an instruction or value is deleted once we've
left SSA form, all variables that used the value implicitly become
"optimized out", something that isn't true of the current DBG_VALUE
approach.
Differential Revision: https://reviews.llvm.org/D85749
(this doesn't cover all cases - libDebugInfoDWARF has a default error
handler that prints errors without any exit code handling - I'll be
following up with a patch for that after this)
When given the -experimental-debug-variable-locations option (via -Xclang
or to llc), have SelectionDAG generate DBG_INSTR_REF instructions instead
of DBG_VALUE. For now, this only happens in a limited circumstance: when
the value referred to is not a PHI and is defined in the current block.
Other situations introduce interesting problems, addresed in later patches.
Practically, this patch hooks into InstrEmitter and if it can find a
defining instruction for a value, gives it an instruction number, and
points the DBG_INSTR_REF at that <instr, operand> pair.
Differential Revision: https://reviews.llvm.org/D85747
This patch defines the MIR format for debug instruction references: it's an
integer trailing an instruction, marked out by "debug-instr-number", much
like how "debug-location" identifies the DebugLoc metadata of an
instruction. The instruction number is stored directly in a MachineInstr.
Actually referring to an instruction comes in a later patch, but is done
using one of these instruction numbers.
I've added a round-trip test and two verifier checks: that we don't label
meta-instructions as generating values, and that there are no duplicates.
Differential Revision: https://reviews.llvm.org/D85746
This patch adds support for DWARF attribute DW_AT_rank.
Summary:
Fortran assumed rank arrays have dynamic rank. DWARF attribute
DW_AT_rank is needed to support that.
Testing:
unit test cases added (hand-written)
check llvm
check debug-info
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D89141
Use SCEV to salvage additional @llvm.dbg.value that have turned into
referencing undef after transformation (and traditional
salvageDebugInfo). Before transformation compute SCEV for each
@llvm.dbg.value in the loop body and store it (along side its current
DIExpression). After transformation update those @llvm.dbg.value now
referencing undef by comparing its stored SCEV to the SCEV of the
current loop-header PHI-nodes. Allow match with offset by inserting
compensation code in the DIExpression.
Includes fix for the nullptr deref that caused the original commit
to be reverted in 9d63029770.
Fixes : PR38815
Differential Revision: https://reviews.llvm.org/D87494
And another step towards transformss not introducing inttoptr and/or
ptrtoint casts that weren't there already.
In this case, when load/store uses have conflicting types,
instead of falling back to the iN, we can try to use allocated sub-type.
As disscussed, this isn't the best idea overall (we shouldn't rely on
allocated type), but it works fine as a temporary measure.
I've measured, and @ `-O3` as of vanilla llvm test-suite + RawSpeed,
this results in +0.05% more bitcasts, -5.51% less inttoptr
and -1.05% less ptrtoint (at the end of middle-end opt pipeline)
See https://bugs.llvm.org/show_bug.cgi?id=47592
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D88788
Register context information was already being passed into the DWARFDebugFrame code that dumps unwind information but it wasn't being used. This change adds the ability to dump registers names of a valid MC register context was passed in and if it knows about the register. Updated the tests to use the newly returned register names.
Differential Revision: https://reviews.llvm.org/D88767
This reverts commit a3caf7f610.
The ReleaseLTO-g test-suite configuration has been failing
to build since this commit, because clang segfaults while
building 7zip.
Use SCEV to salvage additional @llvm.dbg.value that have turned into
referencing undef after transformation (and traditional
salvageDebugInfo). Before transformation compute SCEV for each
@llvm.dbg.value in the loop body and store it (along side its current
DIExpression). After transformation update those @llvm.dbg.value now
referencing undef by comparing its stored SCEV to the SCEV of the
current loop-header PHI-nodes. Allow match with offset by inserting
compensation code in the DIExpression.
Fixes : PR38815
Differential Revision: https://reviews.llvm.org/D87494
It's not possible to do this in complete generality - a CU using a
sec_offset DW_AT_ranges has no way of knowing where its rnglists
contribution starts, so should not attempt to parse any full rnglist
table/header to do so. And even using FORM_rnglistx there's no need to
parse the header - the offset can be computed using the CU's DWARF
format (32 or 64) to compute offset entry sizes, and then the list
parsed at that offset without ever trying to find a rnglist contribution
header immediately prior to the rnglists_base.
This allows LiveDebugValues to insert the proper DBG_VALUEs in live
out blocks if a spill is inserted before the use of a
register. Previously, this would see the register use as the last
DBG_VALUE, even though the stack slot should be treated as the live
out value.
This avoids an lldb test regression when D52010 is re-applied.
attachments. They would crash the backend, which expects all
DISubprograms that are not part of the type system to have a unit field.
Clang right before https://reviews.llvm.org/D79967 would generate this
kind of broken IR.
rdar://problem/69534688
Thanks to Fangrui for fixing an assembler test I had missed!
https://reviews.llvm.org/D88270
attachments. They would crash the backend, which expects all
DISubprograms that are not part of the type system to have a unit field.
Clang right before https://reviews.llvm.org/D79967 would generate this
kind of broken IR.
rdar://problem/69534688
Introduce a helper which can be used to update the debug location of an
Instruction after the instruction is hoisted. This can be used to safely
drop a source location as recommended by the docs.
For more context, see the discussion in https://reviews.llvm.org/D60913.
Differential Revision: https://reviews.llvm.org/D85670
Until then, this one line fix removes the assert fail with basic block sections
with debug info. Bug tracking this: #47549
This fix does not generate loc list or DW_AT_const_value if the argument is
mentioned in a different section than the start of the function.
Temporarily fixes bugzilla : https://bugs.llvm.org/show_bug.cgi?id=47549
Differential Revision: https://reviews.llvm.org/D87787
Flag DIEs that have DW_CHILDREN_yes set in their abbreviation but don't
actually have any children.
rdar://59809554
Differential revision: https://reviews.llvm.org/D88048
If we are going to write handler data (that is written as variable
length data following after the unwind info in .xdata), we need to
emit the handler data immediately, but for cases where no such
info is going to be written, skip emitting it right away. (Unwind
info for all remaining functions that hasn't gotten it emitted
directly is emitted at the end.)
This does slightly change the ordering of sections (triggering a
bunch of updates to DebugInfo/COFF tests), but the change should be
benign.
This also matches GCC's assembly output, which doesn't output
.seh_handlerdata unless it actually is needed.
For ARM64, the unwind info can be packed into the runtime function
entry itself (leaving no data in the .xdata section at all), but
that can only be done if there's no follow-on data in the .xdata
section. If emission of the unwind info is triggered via
EmitWinEHHandlerData (or the .seh_handlerdata directive), which
implicitly switches to the .xdata section, there's a chance of the
caller wanting to pass further data there, so the packed format
can't be used in that case.
Differential Revision: https://reviews.llvm.org/D87448
This rewrites big parts of the fast register allocator. The basic
strategy of doing block-local allocation hasn't changed but I tweaked
several details:
Track register state on register units instead of physical
registers. This simplifies and speeds up handling of register aliases.
Process basic blocks in reverse order: Definitions are known to end
register livetimes when walking backwards (contrary when walking
forward then uses may or may not be a kill so we need heuristics).
Check register mask operands (calls) instead of conservatively
assuming everything is clobbered. Enhance heuristics to detect
killing uses: In case of a small number of defs/uses check if they are
all in the same basic block and if so the last one is a killing use.
Enhance heuristic for copy-coalescing through hinting: We check the
first k defs of a register for COPYs rather than relying on there just
being a single definition. When testing this on the full llvm
test-suite including SPEC externals I measured:
average 5.1% reduction in code size for X86, 4.9% reduction in code on
aarch64. (ranging between 0% and 20% depending on the test) 0.5%
faster compiletime (some analysis suggests the pass is slightly slower
than before, but we more than make up for it because later passes are
faster with the reduced instruction count)
Also adds a few testcases that were broken without this patch, in
particular bug 47278.
Patch mostly by Matthias Braun
Initial support for dwarf fission sections (-gsplit-dwarf) on wasm.
The most interesting change is support for writing 2 files (.o and .dwo) in the
wasm object writer. My approach moves object-writing logic into its own function
and calls it twice, swapping out the endian::Writer (W) in between calls.
It also splits the import-preparation step into its own function (and skips it when writing a dwo).
Differential Revision: https://reviews.llvm.org/D85685
This is needed to support assumed size array of fortran which can have missing upperBound/count
, contrary to current DISubrange support.
Example:
subroutine sub (array1, array2)
integer :: array1 (*)
integer :: array2 (4:9, 10:*)
array1(7:8) = 9
array2(5, 10) = 10
end subroutine
Now the validation check is relaxed for fortran.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D87500
This seems to have caused incorrect register allocation in some cases,
breaking tests in the Zig standard library (PR47278).
As discussed on the bug, revert back to green for now.
> Record internal state based on register units. This is often more
> efficient as there are typically fewer register units to update
> compared to iterating over all the aliases of a register.
>
> Original patch by Matthias Braun, but I've been rebasing and fixing it
> for almost 2 years and fixed a few bugs causing intermediate failures
> to make this patch independent of the changes in
> https://reviews.llvm.org/D52010.
This reverts commit 66251f7e1d, and
follow-ups 931a68f26b
and 0671a4c508. It also adjust some
test expectations.
The patch fixes emitting flags and the debug_line_offset field in
the header, as well as the reference to the macro string for
a pre-standard GNU .debug_macro extension.
Differential Revision: https://reviews.llvm.org/D87024
The patch fixes emitting the unit length field in the header of
the table and offsets to the entry pool. Note that while the patch
changes the common method to emit offsets, in fact, nothing is changed
for Apple accelerator tables, because we do not yet support DWARF64 for
those targets.
Differential Revision: https://reviews.llvm.org/D87023
The patch fixes emitting the header of the table. The content is
independent of the DWARF format.
Differential Revision: https://reviews.llvm.org/D87022
The transition is done by using methods of AsmPrinter which
automatically emit values in compliance with the selected DWARF format.
Differential Revision: https://reviews.llvm.org/D87013
Fangrui Song