Commit Graph

189 Commits

Author SHA1 Message Date
Roman Lebedev 7850ab2112
[NFC] Port an assortment of tests that invoke SROA to new pass manager 2022-12-01 21:17:18 +03:00
Archibald Elliott d59ce7d0ea [ARM] Specify Triple in DebugInfo Tests
When the host's target triple ends in `-windows-msvc`, `%llc_dwarf`
contains an explicit `-windows-gnu` triple which ensures that dwarf will
be used. This is useful in target-independent tests, where no triple is
specified, and no target-specific features are used. However, this is
not compatible with target-dependent tests (such as those in
llvm/test/DebugInfo/ARM), as the command-line triple will override the
triple in the LLVM IR program, causing test issues on windows.

This change switches these tests to use an explicit triple, so the tests
test what was expected, and there is no flakiness on windows.

Fixes #58053

Differential Revision: https://reviews.llvm.org/D136066
2022-11-01 14:55:33 +00:00
Muhammad Omair Javaid 4dcf7b5c89 [LLVM][DebugInfo] Disable split-complex.ll for aarch64-pc-windows-msvc
This patch disables split-complex.ll for aarch64-pc-windows-msvc.
split-complex.ll fails with a crash when run on AArch64/Windows.
I have reported following issue: llvm-project/issues/58053
2022-09-29 16:35:04 +05:00
Nikita Popov 4bb7b6fae3 [IR] Remove support for float binop constant expressions
As part of https://discourse.llvm.org/t/rfc-remove-most-constant-expressions/63179,
this removes support for the floating-point binop constant expressions
fadd, fsub, fmul, fdiv and frem.

As part of this change, the C APIs LLVMConstFAdd, LLVMConstFSub,
LLVMConstFMul, LLVMConstFDiv and LLVMConstFRem are removed.
The LLVMBuild APIs should be used instead.

Differential Revision: https://reviews.llvm.org/D129478
2022-07-12 09:40:49 +02:00
Keith Walker 94fac097ad [DebugInfo][ARM] Not readonly check for RWPI globals
When compiling for the RWPI relocation model [1], the debug information
is wrong for readonly global variables.

Writable global variables are accessed by the static base register (R9
on ARM) in the RWPI relocation model.  This is being correctly generated

Readonly global variables are not accessed by the static base register
in the RWPI relocation model. This case is incorrectly generating the
same debugging information as for writable global variables.

References:
[1] ARM Read-Write Position Independence: https://github.com/ARM-software/abi-aa/blob/main/aapcs32/aapcs32.rst#read-write-position-independence-rwpi

Differential Revision: https://reviews.llvm.org/D126361
2022-06-15 11:52:12 +01:00
David Green a86cfaea54 [ARM] Add register-mask for tail returns
The TC_RETURN/TCRETURNdi under Arm does not currently add the
register-mask operand when tail folding, which leads to the register
(like LR) not being 'used' by the return. This changes the code to
unconditionally set the register mask on the call, as opposed to
skipping it for tail calls.

I don't believe this will currently alter any codegen, but should glue
things together better post-frame lowering. It matches the AArch64 code
better.

Differential Revision: https://reviews.llvm.org/D125906
2022-05-21 15:28:24 +01:00
Jeremy Morse 920de9c94c Revert "[DebugInfo] Correctly recognize bitfields when emitting dwarf"
This reverts commit 059d1f84d2.

Some tests on green dragon failed as a result of this -- see notes on D96334.
2022-04-04 17:14:58 +01:00
Jeremy Morse 059d1f84d2 [DebugInfo] Correctly recognize bitfields when emitting dwarf
Use the "isBitfield" flag for debug types to determine whether something is
a bitfield, rather than trying to guess from it's layout. Fixes
https://bugs.llvm.org/show_bug.cgi?id=44601

Patch by: mahkoh

Differential Revision: https://reviews.llvm.org/D96334
2022-04-04 11:14:13 +01:00
Dávid Bolvanský fb65aaf0be [NFCI] Fixed missing colon in CHECK directives - part 2 2022-04-03 14:42:59 +02:00
Alexandros Lamprineas 04dc68710a [DebugInfo][ARM] Fix incorrect debug information for RWPI accessed globals
When compiling for the RWPI relocation model the debug information is wrong:

* the debug location is described as { DW_OP_addr Var }
  instead of { DW_OP_constNu Var DW_OP_bregX 0 DW_OP_plus }
* the relocation type is R_ARM_ABS32 instead of R_ARM_SBREL32

Differential Revision: https://reviews.llvm.org/D111404
2021-10-18 21:29:46 +01:00
Jeremy Morse c4ede6d608 [DebugInfo][InstrRef] Avoid a crash during DBG_PHI maintenence
With D110105, the isDebug flag for register uses is now a proxy for whether
the instruction is a debug instruction; that causes DBG_PHIs to have their
operands updated by calls to updateDbgUsersToReg, which is the correct
behaviour. However: that function only expects to receive DBG_VALUE
instructions and asserts such.

This patch splits the updating-action into a lambda, and applies it to the
appropriate operands for each kind of debug instruction. Tested with an
ARM test that stimulates this function: I've added some DBG_PHI
instructions that should be updated in the same way as DBG_VALUEs.

Differential Revision: https://reviews.llvm.org/D108641
2021-10-18 11:52:45 +01:00
Jeremy Morse 8612417e5a [DebugInfo][InstrRef] Don't break up ret-sequences on debug-info instrs
When we have a terminator sequence (i.e. a tailcall or return),
MIIsInTerminatorSequence is used to work out where the preceding ABI-setup
instructions end, i.e. the parts that were glued to the terminator
instruction. This allows LLVM to split blocks safely without having to
worry about ABI stuff.

The function only ignores DBG_VALUE instructions, meaning that the two
debug instructions I recently added can end terminator sequences early,
causing various MachineVerifier errors. This patch promotes the test for
debug instructions from "isDebugValue" to "isDebugInstr", thus avoiding any
debug-info interfering with this function.

Differential Revision: https://reviews.llvm.org/D106660
2021-07-28 15:56:00 +01:00
Wolfgang Pieb d1116697be [ARM] Fix RELA relocations for 32bit ARM.
RELA relocations for 32 bit ARM ignored the addend. Some tools generate
them instead of REL type relocations. This fixes PR50473.

    Reviewed By: MaskRay, peter.smith

    Differential Revision: https://reviews.llvm.org/D105214
2021-07-14 14:27:15 -07:00
Jeremy Morse 1575583f2a [LiveDebugValues][InstrRef][2/2] Emit entry value variable locations
This patch adds support to the instruction-referencing LiveDebugValues
implementation for emitting entry values. The instruction referencing
implementations tracking by value rather than location means that we can
get around two of the issues with VarLocs. DBG_VALUE instructions that
re-assign the same value to a variable are no longer a problem, because we
can "see through" to the value being assigned. We also don't need to do
anything special during the dataflow stages: the "variable value problem"
doesn't need to know whether a value is available most of the time, and the
times it deoes need to know are always when entry values need to be
terminated.

The patch modifies the "TransferTracker" class, adding methods to identify
when a variable ias an entry value candidate, and when a machine value is
an entry value. recoverAsEntryValue tests these two things and emits an
entry-value expression if they're true. It's used when we clobber or
otherwise lose a value and can't find a replacement location for the value
it contained.

Differential Revision: https://reviews.llvm.org/D88406
2021-06-30 23:07:39 +01:00
Matt Arsenault fae05692a3 CodeGen: Print/parse LLTs in MachineMemOperands
This will currently accept the old number of bytes syntax, and convert
it to a scalar. This should be removed in the near future (I think I
converted all of the tests already, but likely missed a few).

Not sure what the exact syntax and policy should be. We can continue
printing the number of bytes for non-generic instructions to avoid
test churn and only allow non-scalar types for generic instructions.

This will currently print the LLT in parentheses, but accept parsing
the existing integers and implicitly converting to scalar. The
parentheses are a bit ugly, but the parser logic seems unable to deal
without either parentheses or some keyword to indicate the start of a
type.
2021-06-30 16:54:13 -04:00
serge-sans-paille 4ab3041acb Revert "[NFC] remove explicit default value for strboolattr attribute in tests"
This reverts commit bda6e5bee0.

See https://lab.llvm.org/buildbot/#/builders/109/builds/15424 for instance
2021-05-24 19:43:40 +02:00
serge-sans-paille bda6e5bee0 [NFC] remove explicit default value for strboolattr attribute in tests
Since d6de1e1a71, no attributes is quivalent to
setting attribute to false.

This is a preliminary commit for https://reviews.llvm.org/D99080
2021-05-24 19:31:04 +02:00
Stephen Tozer fdb055f4f1 Reapply "[DebugInfo] Fix updateDbgUsersToReg to support DBG_VALUE_LIST"
Previous crashes caused by this patch were the result of machine
subregisters being incorrectly handled in updateDbgUsersToReg; this has
been fixed by using RegUnits to determine overlapping registers, instead
of using the register values directly.

Differential Revision: https://reviews.llvm.org/D101523

This reverts commit 7ca26c5fa2.
2021-05-12 10:19:57 +01:00
Arthur Eubanks 7ca26c5fa2 Revert "[DebugInfo] Fix updateDbgUsersToReg to support DBG_VALUE_LIST"
This reverts commit 0791f968fe.

Causing crashes: https://crbug.com/1206764
2021-05-07 12:05:16 -07:00
Stephen Tozer 0791f968fe [DebugInfo] Fix updateDbgUsersToReg to support DBG_VALUE_LIST
This patch modifies updateDbgUsersToReg to properly handle
DBG_VALUE_LIST instructions, by replacing the hard-coded operand indices
(i.e. getOperand(0)) with the more general getDebugOperandsForReg(), and
updating the register for all matching operands.

Differential Revision: https://reviews.llvm.org/D101523
2021-05-07 11:47:50 +01:00
Pavel Labath bce2ac9f6d Revert "[DebugInfo] Refactor code for emitting DWARF expressions for FP constants"
The commit introduced a crash when emitting (debug info for) complex
floats (pr48277).
2020-11-24 09:11:33 +01:00
Pavel Labath 6ef7835afc [DebugInfo] Refactor code for emitting DWARF expressions for FP constants
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
2020-11-23 09:59:07 +01:00
Matt Arsenault 20c43d6bd5 OpaquePtr: Bulk update tests to use typed sret 2020-11-20 17:58:26 -05:00
Roman Lebedev 7fa503ef4a
[SROA] rewritePartition()/findCommonType(): if uses have conflicting type, try getTypePartition() before falling back to largest integral use type (PR47592)
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
2020-10-07 09:20:19 +03:00
Matt Arsenault 89baeaef2f Reapply "RegAllocFast: Rewrite and improve"
This reverts commit 73a6a164b8.
2020-09-30 10:35:25 -04:00
Muhammad Omair Javaid 73a6a164b8 Revert "Reapply Revert "RegAllocFast: Rewrite and improve""
This reverts commit 55f9f87da2.

Breaks following buildbots:
http://lab.llvm.org:8011/builders/lldb-arm-ubuntu/builds/4306
http://lab.llvm.org:8011/builders/lldb-aarch64-ubuntu/builds/9154
2020-09-22 14:40:06 +05:00
Matt Arsenault 55f9f87da2 Reapply Revert "RegAllocFast: Rewrite and improve"
This reverts commit dbd53a1f0c.

Needed lldb test updates
2020-09-21 15:45:27 -04:00
Eric Christopher dbd53a1f0c Temporarily Revert "RegAllocFast: Rewrite and improve"
as it's breaking a few tests in the lldb test suite.

Bot: http://lab.llvm.org:8011/builders/lldb-arm-ubuntu/builds/4226/steps/test/logs/stdio

This reverts commit c8757ff3aa.
2020-09-18 18:11:21 -07:00
Matt Arsenault c8757ff3aa RegAllocFast: Rewrite and improve
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
2020-09-18 14:05:18 -04:00
OCHyams ce6de3747b [DebugInfo] Drop location ranges for variables which exist entirely outside the variable's scope
Summary:
This patch reduces file size in debug builds by dropping variable locations a
debugger user will not see.

After building the debug entity history map we loop through it. For each
variable we look at each entry. If the entry opens a location range which does
not intersect any of the variable's scope's ranges then we mark it for removal.
After visiting the entries for each variable we also mark any clobbering
entries which will no longer be referenced for removal, and then finally erase
the marked entries. This all requires the ability to query the order of
instructions, so before this runs we number them.

Tests:
Added llvm/test/DebugInfo/X86/trim-var-locs.mir

Modified llvm/test/DebugInfo/COFF/register-variables.ll
  Branch folding merges the tails of if.then and if.else into if.else. Each
  blocks' debug-locations point to different scopes so when they're merged we
  can't use either. Because of this the variable 'c' ends up with a location
  range which doesn't cover any instructions in its scope; with the patch
  applied the location range is dropped and its flag changes to IsOptimizedOut.

Modified llvm/test/DebugInfo/X86/live-debug-variables.ll
Modified llvm/test/DebugInfo/ARM/PR26163.ll
  In both tests an out of scope location is now removed. The remaining location
  covers the entire scope of the variable allowing us to emit it as a single
  location.

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D82129
2020-07-22 12:45:21 +01:00
Yvan Roux bd069ad39c [ARM] Move ConstantIsland and LowOverheadLoops Passes.
Move ARM ConstantIsland and LowOverheadLopps passes later in the pipeline
such that they will be run after the upcoming Machine Outlining pass.

Differential Revision: https://reviews.llvm.org/D76065
2020-03-25 16:49:21 +01:00
Fangrui Song 536ba6373f [Object] Change ELFObjectFile<ELFT>::getFileFormatName() to use BFD names
Follow-up for D74433

What the function returns are almost standard BFD names, except that "ELF" is
in uppercase instead of lowercase.

This patch changes "ELF" to "elf" and changes ARM/AArch64 to use their BFD names.
MIPS and PPC64 have endianness differences as well, but this patch does not intend to address them.

Advantages:

* llvm-objdump: the "file format " line matches GNU objdump on ARM/AArch64 objects
* "file format " line can be extracted and fed into llvm-objcopy -O literally.
  (https://github.com/ClangBuiltLinux/linux/issues/779 has such a use case)

Affected tools: llvm-readobj, llvm-objdump, llvm-dwarfdump, MCJIT (internal implementation detail, not exposed)

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D76046
2020-03-16 07:42:04 -07:00
Djordje Todorovic c15c68abdc [CallSiteInfo] Enable the call site info only for -g + optimizations
Emit call site info only in the case of '-g' + 'O>0' level.

Differential Revision: https://reviews.llvm.org/D75175
2020-03-09 12:12:44 +01:00
Djordje Todorovic 2f215cf36a Revert "Reland "[DebugInfo] Enable the debug entry values feature by default""
This reverts commit rGfaff707db82d.
A failure found on an ARM 2-stage buildbot.
The investigation is needed.
2020-02-20 14:41:39 +01:00
Djordje Todorovic faff707db8 Reland "[DebugInfo] Enable the debug entry values feature by default"
Differential Revision: https://reviews.llvm.org/D73534
2020-02-19 11:12:26 +01:00
Djordje Todorovic 2bf44d11cb Revert "Reland "[DebugInfo] Enable the debug entry values feature by default""
This reverts commit rGa82d3e8a6e67.
2020-02-18 16:38:11 +01:00
Djordje Todorovic a82d3e8a6e Reland "[DebugInfo] Enable the debug entry values feature by default"
This patch enables the debug entry values feature.

  - Remove the (CC1) experimental -femit-debug-entry-values option
  - Enable it for x86, arm and aarch64 targets
  - Resolve the test failures
  - Leave the llc experimental option for targets that do not
    support the CallSiteInfo yet

Differential Revision: https://reviews.llvm.org/D73534
2020-02-18 14:41:08 +01:00
Djordje Todorovic 97ed706a96 Revert "[DebugInfo] Enable the debug entry values feature by default"
This reverts commit rG9f6ff07f8a39.

Found a test failure on clang-with-thin-lto-ubuntu buildbot.
2020-02-12 11:59:04 +01:00
Djordje Todorovic 9f6ff07f8a [DebugInfo] Enable the debug entry values feature by default
This patch enables the debug entry values feature.

  - Remove the (CC1) experimental -femit-debug-entry-values option
  - Enable it for x86, arm and aarch64 targets
  - Resolve the test failures
  - Leave the llc experimental option for targets that do not
    support the CallSiteInfo yet

Differential Revision: https://reviews.llvm.org/D73534
2020-02-12 10:25:14 +01:00
Ted Woodward 7683a084de Remove lit feature object-emission
Summary: The lit feature object-emission was added because Hexagon did not support the integrated assembler, so some tests needed to be turned off with a Hexagon target. Hexagon now supports the integrated assembler, so this feature can be removed.

Reviewers: bcain, kparzysz, jverma, whitequark, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: mehdi_amini, hiraditya, steven_wu, dexonsmith, arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73568
2020-02-10 15:57:56 -06:00
Jeremy Morse 6531a78ac4 Revert "[DebugInfo] Remove some users of DBG_VALUEs IsIndirect field"
This reverts commit ed29dbaafa.

I'm backing out D68945, which as the discussion for D73526 shows, doesn't
seem to handle the -O0 path through the codegen backend correctly. I'll
reland the patch when a fix is worked out, apologies for all the churn.
The two parent commits are part of this revert too.

Conflicts:
	llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
	llvm/test/DebugInfo/X86/dbg-addr-dse.ll

SelectionDAGBuilder conflict is due to a nearby change in e39e2b4a79
that's technically unrelated. dbg-addr-dse.ll conflicted because
41206b61e3 (legitimately) changes the order of two lines.

There are further modifications to dbg-value-func-arg.ll: it landed after
the patch being reverted, and I've converted indirection to be represented
by the isIndirect field rather than DW_OP_deref.
2020-02-06 14:41:40 +00:00
Fangrui Song 26ba1f77b5 [DebugInfo][test] Change two MIR tests to use -start-before=livedebugvalues instead of -start-after=patchable-function
To break order dependency between livedebugvalues and patchable-function.
2020-01-19 00:09:46 -08:00
Fangrui Song a36ddf0aa9 Migrate function attribute "no-frame-pointer-elim"="false" to "frame-pointer"="none" as cleanups after D56351 2019-12-24 16:27:51 -08:00
Fangrui Song 502a77f125 Migrate function attribute "no-frame-pointer-elim" to "frame-pointer"="all" as cleanups after D56351 2019-12-24 15:57:33 -08:00
Djordje Todorovic 979592a6f7 [DebugInfo] Remove the DIFlagArgumentNotModified debug info flag
Due to changes in D68206, we remove the DIFlagArgumentNotModified
and its usage.

Differential Revision: https://reviews.llvm.org/D68207
2019-11-20 13:18:40 +01:00
Pavel Labath dca2b36ba0 Re-commit "DWARF location lists: Add section index dumping"
This reapplies c0f6ad7d1f with an
additional fix in test/DebugInfo/X86/constant-loclist.ll, which had a
slightly different output on windows targets. The test now accounts for
this difference.

The original commit message follows.

Summary:
As discussed in D70081, this adds the ability to dump section
names/indices to the location list dumper. It does this by moving the
range specific logic from DWARFDie.cpp:dumpRanges into the
DWARFAddressRange class.

The trickiest part of this patch is the backflip in the meanings of the
two dump flags for the location list sections.

The dumping of "raw" location list data is now controlled by
"DisplayRawContents" flag. This frees up the "Verbose" flag to be used
to control whether we print the section index. Additionally, the
DisplayRawContents flag is set for section-based dumps whenever the
--verbose option is passed, but this is not done for the "inline" dumps.

Also note that the index dumping currently does not work for the DWARF
v5 location lists, as the parser does not fill out the appropriate
fields. This will be done in a separate patch.

Reviewers: dblaikie, probinson, JDevlieghere, SouraVX

Subscribers: sdardis, hiraditya, jrtc27, atanasyan, arphaman, aprantl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70227
2019-11-18 15:30:10 +01:00
Simon Pilgrim c070a27acc Revert rGc0f6ad7d1f3c : "DWARF location lists: Add section index dumping"
This reverts commit c0f6ad7d1f to fix the buildbots.
2019-11-18 13:26:51 +00:00
Pavel Labath c0f6ad7d1f DWARF location lists: Add section index dumping
Summary:
As discussed in D70081, this adds the ability to dump section
names/indices to the location list dumper. It does this by moving the
range specific logic from DWARFDie.cpp:dumpRanges into the
DWARFAddressRange class.

The trickiest part of this patch is the backflip in the meanings of the
two dump flags for the location list sections.

The dumping of "raw" location list data is now controlled by
"DisplayRawContents" flag. This frees up the "Verbose" flag to be used
to control whether we print the section index. Additionally, the
DisplayRawContents flag is set for section-based dumps whenever the
--verbose option is passed, but this is not done for the "inline" dumps.

Also note that the index dumping currently does not work for the DWARF
v5 location lists, as the parser does not fill out the appropriate
fields. This will be done in a separate patch.

Reviewers: dblaikie, probinson, JDevlieghere, SouraVX

Subscribers: sdardis, hiraditya, jrtc27, atanasyan, arphaman, aprantl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70227
2019-11-18 10:50:22 +01:00
David Stenberg 1ae2d9a2bd [DebugInfo] Add a DW_OP_LLVM_entry_value operation
Summary:
Internally in LLVM's metadata we use DW_OP_entry_value operations with
the same semantics as DWARF; that is, its operand specifies the number
of bytes that the entry value covers.

At the time of emitting entry values we don't know the emitted size of
the DWARF expression that the entry value will cover. Currently the size
is hardcoded to 1 in DIExpression, and other values causes the verifier
to fail. As the size is 1, that effectively means that we can only have
valid entry values for registers that can be encoded in one byte, which
are the registers with DWARF numbers 0 to 31 (as they can be encoded as
single-byte DW_OP_reg0..DW_OP_reg31 rather than a multi-byte
DW_OP_regx). It is a bit confusing, but it seems like llvm-dwarfdump
will print an operation "correctly", even if the byte size is less than
that, which may make it seem that we emit correct DWARF for registers
with DWARF numbers > 31. If you instead use readelf for such cases, it
will interpret the number of specified bytes as a DWARF expression. This
seems like a limitation in llvm-dwarfdump.

As suggested in D66746, a way forward would be to add an internal
variant of DW_OP_entry_value, DW_OP_LLVM_entry_value, whose operand
instead specifies the number of operations that the entry value covers,
and we then translate that into the byte size at the time of emission.

In this patch that internal operation is added. This patch keeps the
limitation that a entry value can only be applied to simple register
locations, but it will fix the issue with the size operand being
incorrect for DWARF numbers > 31.

Reviewers: aprantl, vsk, djtodoro, NikolaPrica

Reviewed By: aprantl

Subscribers: jyknight, fedor.sergeev, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D67492

llvm-svn: 374881
2019-10-15 11:31:21 +00:00
Jeremy Morse ed29dbaafa [DebugInfo] Remove some users of DBG_VALUEs IsIndirect field
This patch kills off a significant user of the "IsIndirect" field of
DBG_VALUE machine insts. Brought up in in PR41675, IsIndirect is
techncally redundant as it can be expressed by the DIExpression of a
DBG_VALUE inst, and it isn't helpful to have two ways of expressing
things.

Rather than setting IsIndirect, have DBG_VALUE creators add an extra deref
to the insts DIExpression. There should now be no appearences of
IsIndirect=True from isel down to LiveDebugVariables / VirtRegRewriter,
which is ensured by an assertion in LDVImpl::handleDebugValue. This means
we also get to delete the IsIndirect handling in LiveDebugVariables. Tests
can be upgraded by for example swapping the following IsIndirect=True
DBG_VALUE:

  DBG_VALUE $somereg, 0, !123, !DIExpression(DW_OP_foo)

With one where the indirection is in the DIExpression, by _appending_
a deref:

  DBG_VALUE $somereg, $noreg, !123, !DIExpression(DW_OP_foo, DW_OP_deref)

Which both mean the same thing. 

Most of the test changes in this patch are updates of that form; also some
changes in how the textual assembly printer handles these insts.

Differential Revision: https://reviews.llvm.org/D68945

llvm-svn: 374877
2019-10-15 10:46:24 +00:00