Commit Graph

678 Commits

Author SHA1 Message Date
Fangrui Song d797c2ffdb [DebugInfo] -fdebug-prefix-map: handle '#line "file"' for asm source
`getContext().setMCLineTableRootFile` (from D62074) sets `RootFile.Name` to
`FirstCppHashFilename`. `RootFile.Name` is not processed by -fdebug-prefix-map
and will go to DW_TAG_compile_unit's DT_AT_name and DW_TAG_label's
DW_AT_decl_file. Remap `RootFile.Name`.

Fix another issue reported by https://github.com/llvm/llvm-project/issues/56609

Reviewed By: #debug-info, dblaikie, raj.khem

Differential Revision: https://reviews.llvm.org/D131848
2022-08-14 20:58:23 -07:00
Fangrui Song 3329cec2f7 [DebugInfo] Don't join DW_AT_comp_dir and directories[0] for DWARF v5 line tables
DWARF v5 6.2.4 The Line Number Program Header says:

> The first entry is the current directory of the compilation. Each additional
> path entry is either a full path name or is relative to the current directory of
> the compilation.

When forming a path, relative DW_AT_comp_dir and directories[0] are not supposed
to be joined together. Fix getFileNameByIndex to special case DWARF v5 DirIdx == 0.

Reviewed By: #debug-info, dblaikie

Differential Revision: https://reviews.llvm.org/D131804
2022-08-12 14:01:52 -07:00
Fangrui Song f62e60fb23 [MCDwarf] Respect -fdebug-prefix-map= for generated assembly debug info (DWARF v5)
For generated assembly debug info, MCDwarfLineTableHeader::CompilationDir is an
unmapped path set in MCContext::setGenDwarfRootFile. Remap it.

A relative destination path of -fdebug-prefix-map= exposes a llvm-dwarfdump bug
which joins relative DW_AT_comp_dir and directories[0].

Fix https://github.com/llvm/llvm-project/issues/56609

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D131749
2022-08-12 12:52:36 -07:00
Fangrui Song d561907f27 [MCDwarf][test] Improve debug-prefix-map.s 2022-08-11 22:40:31 -07:00
Fangrui Song 9f0d5330bd [MC][test] Rename two --compress-debug-sections=zlib tests
To be clearer when zstd support is added.
2022-07-28 10:57:56 -07:00
David Blaikie 61891748f5 Remove testing for zlib-gnu llvm-mc support in the absence of zlib 2022-07-14 22:55:47 +00:00
David Blaikie d63ec445ca Remove zlibgnu support in llvm-mc
The feature's been removed from most other tools in LLVM at this point.
2022-07-14 22:38:59 +00:00
Fangrui Song e07dfa5328 [MC][ELF] Improve st_size propagation rule
`.symver foo, foo@ver` creates the MCSymbolELF `foo@ver` whose almost all
attributes (including st_size) should inherit from `foo` (GNU as behavior).

a041ef1bd8 added st_size propagation which works
for many cases but fails for the following one:

```
.set __GLIBC_2_12_sys_errlist, _sys_errlist_internal
.type   __GLIBC_2_12_sys_errlist,@object
.size   __GLIBC_2_12_sys_errlist, 1080
.symver __GLIBC_2_12_sys_errlist, sys_errlist@GLIBC_2.12
...
_sys_errlist_internal:
.size   _sys_errlist_internal, 1072
```

`sys_errlist@GLIBC_2.12`'s st_size is 1072 (incorrect), which does not match
`__GLIBC_2_12_sys_errlist`'s st_size: 1080.

The problem is that `Base` is (the final) `_sys_errlist_internal` while we want
to respect (the intermediate) `__GLIBC_2_12_sys_errlist`'s st_size.
Fix this by following the MCSymbolRefExpr assignment chain and finding
the closest non-null `getSize()`, which covers most needs. Notably MCBinaryExpr
is not handled, but it is rare enough to matter.

Reviewed By: peter.smith

Differential Revision: https://reviews.llvm.org/D123283
2022-04-08 10:06:44 -07:00
Fangrui Song 67acc34e2a [MC][test] Improve offset.s 2022-04-08 09:58:04 -07:00
Fangrui Song 6bdad85b26 [MC] Fix llvm_unreachable when a STB_GNU_UNIQUE symbol needs a relocation
STB_GNU_UNIQUE should be treated in a way similar to STB_GLOBAL.
This fixes an "Invalid Binding" failure in an LLVM_ENABLE_ASSERTIONS=on build
for source files like glibc elf/tst-unique1mod1.c .

This bug has been benign so far because (a) Clang does not produce
%gnu_unique_object by itself (b) a non-assertion build likely picks the
STB_GLOBAL code path anyway.
2022-03-28 13:40:48 -07:00
Igor Kudrin c344d97a12 [NVPTX][tests] Do not run tests that require direct object generation
NVPTX does not support generating binary files, which is required for
these tests.

The majority of tests in 'DebugInfo/Generic' also require emitting
object files, so they all are disabled for NVPTX.

Differential Revision: https://reviews.llvm.org/D121996
2022-03-22 16:46:48 +04:00
Fangrui Song 1caee67dac [MC][test] Add more .loc directives to improve portability with older zlib
Make .debug_line so larger so that MC will more assuredly compress .debug_line
(it doesn't compress a section if compressed content is not smaller).
2022-03-14 22:33:08 -07:00
Fangrui Song 6ca22623c9 [MC][test] Improve compression.s
* Actually test compressed .debug_line for 32-bit
* Test .debug_frame can be compressed
* Test a section not named .debug_* is not compressed
2022-03-11 14:42:07 -08:00
Martin Storsjö 9e2236fb7b Reapply [lit] Read command stdout/stderr as text on Windows
This takes care of normalizing newlines back to single LF instead
of CRLF.

Fix up a couple tests that accidentally pass binary data to stdout.

Differential Revision: https://reviews.llvm.org/D120623
2022-03-03 13:31:31 +02:00
Martin Storsjö f570da28e6 Revert "[lit] Read command stdout/stderr as text on Windows"
This reverts commit 640e45b9b2.

That commit seemed to quite conclusively break a number of buildbots.
2022-03-01 14:43:55 +02:00
Martin Storsjö 640e45b9b2 [lit] Read command stdout/stderr as text on Windows
This takes care of normalizing newlines back to single LF instead
of CRLF.

This on itself breaks on a couple tests that accidentally seem to
be writing binary data to stdout; make sure those cases are piped
to /dev/null instead of actually written to a terminal.

Differential Revision: https://reviews.llvm.org/D120623
2022-03-01 14:24:02 +02:00
Rainer Orth 365be7ac72 [MC][ELF] Use SHF_SUNW_NODISCARD instead of SHF_GNU_RETAIN on Solaris
As requested in D107955 <https://reviews.llvm.org/D107955>, this patch
splits off the `MC` and `CodeGen` parts and adds a testcase.

Tested on `sparcv9-sun-solaris2.11`, `amd64-pc-solaris2.11`, and
`x86_64-pc-linux-gnu`.

Differential Revision: https://reviews.llvm.org/D120318
2022-02-23 15:43:12 +01:00
Fangrui Song 426437d1fe [MC] Add MCAsmParser::parseRParen to improve consistency and simplify code
Some diagnostics are more verbose but they don't seem to be more useful than
simple `expected ')'`
2022-01-27 00:37:49 -08:00
Igor Kudrin 75184f14ae [DebugInfo] Fix handling '# line "file"' for DWARFv5
`CppHashInfo.Filename` is a `StringRef` that references a part of the
source file and it is not null-terminated at the end of the file name.
`AsmParser::parseAndMatchAndEmitTargetInstruction()` passes it to
`getStreamer().emitDwarfFileDirective()`, and it eventually comes to
`isRootFile()`. The comparison fails because `FileName.data()` is not
properly terminated.

In addition, the old code might cause a significant speed degradation
for long source files. The `operator!=()` for `std::string` and
`const char *` can be implemented in a way that it finds the length of
the second argument first, which slows the comparison for long data.
`parseAndMatchAndEmitTargetInstruction()` calls
`emitDwarfFileDirective()` every time if `CppHashInfo.Filename` is not
empty. As a result, the longer the source file is, the slower the
compilation wend, and for a very long file, it might take hours instead
of a couple of seconds normally.

Differential Revision: https://reviews.llvm.org/D117785
2022-01-21 13:52:10 +07:00
Sami Tolvanen 9a74c753fe [ThinLTO][MC] Use conditional assignments for promotion aliases
Inline assembly refererences to static functions with ThinLTO+CFI were
fixed in D104058 by creating aliases for promoted functions. Creating
the aliases unconditionally resulted in an unexpected size increase in
a Chrome helper binary:

https://bugs.chromium.org/p/chromium/issues/detail?id=1261715

This is caused by the compiler being unable to drop unused code now
referenced by the alias in module-level inline assembly. This change
adds a .set_conditional assembly extension, which emits an assignment
only if the target symbol is also emitted, avoiding phantom references
to functions that could have otherwise been dropped.

This is an alternative to the solution proposed in D112761.

Reviewed By: pcc, nickdesaulniers, MaskRay

Differential Revision: https://reviews.llvm.org/D113613
2021-12-10 12:21:37 -08:00
Tobias Burnus c01c62c76c [MC][ELF] Fix accepting abbreviated form with Type change
Follow up to D92052 and D94072, exposed due to D107707

Many assemblers to permit that only the first .section contains all
the attributes like '.lds_bss,"w",@nobits' and later section only
use the name ('.lds_bss') inheriting those attributes from the first
section.  I turned out that the case that Type changed was missed
when implementing it - and D107707 make it much more likely to hit
that issue. That's fixed by this commit.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D114717
2021-11-30 14:45:26 +00:00
Jake Egan fa1dd5fdee [AIX] Disable cfi-version test on AIX
`.debug_frame` is not emitted on AIX, so this patch disables the test.

Reviewed By: shchenz, jsji

Differential Revision: https://reviews.llvm.org/D112593
2021-10-31 09:33:13 -04:00
Jake Egan ff3b542e7c [AIX] Disable tests failing due to lack of .loc and .file directive support
The following tests explicitly check for .loc and .file directives, which is not currently supported. Disable these tests on AIX for now.

Reviewed By: shchenz

Differential Revision: https://reviews.llvm.org/D111346
2021-10-08 11:55:12 -04:00
Fangrui Song dfb7518df1 [MC] Set SHF_INFO_LINK on SHT_REL/SHT_RELA sections
sh_info links to a section, therefore SHF_INFO_LINK should be set as GNU as
does. The issue has been benign because linkers kindly combines relocation
sections w/ and w/o the flag.
2021-09-02 01:00:51 -07:00
Fangrui Song 83dfa0d098 [MC] Change ELFOSABI_NONE to ELFOSABI_GNU for STB_GNU_UNIQUE
Similar to D97976.
On Linux, most GCC installations are configured with
`--enable-gnu-unique-object` and such GCC emits `@gnu_unique_object` assembly.

The feature is highly controversial and disliked by many folks.
(On glibc DF_1_NODELETE is implicitly enabled and makes dlclose a no-op).

In llvm-project STB_GNU_UNIQUE is assembly only. Clang does not use STB_GNU_UNIQUE.

Use ELFOSABI_GNU to match GNU as behavior and avoid collision with other
OSABI binding values.

Reviewed By: jrtc27

Differential Revision: https://reviews.llvm.org/D107861
2021-08-27 08:53:55 -07:00
Rainer Orth 8738c5b0fe [MC][ELF] Mark Solaris objects as ELFOSABI_SOLARIS
Prompted by D107747 <https://reviews.llvm.org/D107747>, it seems prudent to
mark objects as `ELFOSABI_SOLARIS` on Solaris.

Tested on `amd64-pc-solaris2.11`, `sparcv9-sun-solaris2.11`, and
`x86_64-pc-linux-gnu`.

Differential Revision: https://reviews.llvm.org/D107748
2021-08-13 14:31:32 +02:00
David Spickett 6f8c4340c2 [llvm][MC] Disable cfi-version test for Windows on Arm
Like Windows on x86-64, Windows on arm64 uses structured
exception handling, so we don't emit .debug_frame.

See:
https://docs.microsoft.com/en-us/cpp/build/arm64-exception-handling?view=msvc-160

Reviewed By: ostannard

Differential Revision: https://reviews.llvm.org/D107440
2021-08-04 11:18:05 +00:00
Fangrui Song aa3df8ddcd [test] Avoid llvm-readelf/llvm-readobj one-dash long options and deprecated aliases (e.g. --file-headers) 2021-07-15 10:26:21 -07:00
Anirudh Prasad 7bc1baea6e [MCParser][z/OS] Mark a few tests as unsupported for the z/OS Target
- Background here is that that these sets of tests are "invalid" to be run on z/OS
- The reason is because these test constructs that HLASM never supports (HLASM doesn't support GNU style directives)
- Usually tests are geared towards a particular target via the use of a triple that targets just that platform, but these tests require the use of a "default triple"
- Thus, we mark these tests as "UNSUPPORTED" for z/OS since we don't want to run these for z/OS

Reviewed By: yusra.syeda, abhina.sreeskantharajan

Differential Revision: https://reviews.llvm.org/D105204
2021-07-05 11:06:52 -04:00
Fangrui Song a9854045f6 [test] Change -t to --syms and -s to -S for llvm-readobj RUN lines
-s and -t will be changed to improve consistency with llvm-readelf.
The inconsistency issue regularly contributes to confusion using the two tools.
2021-06-29 11:50:31 -07:00
Fangrui Song ca3bdb57fa [MC][ELF] Change SHT_LLVM_CALL_GRAPH_PROFILE relocations from SHT_RELA to SHT_REL
... even on targets preferring RELA. The section is only consumed by ld.lld
which can handle REL.

Follow-up to D104080 as I explained in the review. There are two advantages:

* The D104080 code only handles RELA, so arm/i386/mips32 etc may warn for -fprofile-use=/-fprofile-sample-use= usage.
* Decrease object file size for RELA targets

While here, change the relocation to relocate weights, instead of 0,1,2,3,..
I failed to catch the issue during review.
2021-06-24 21:35:48 -07:00
Alexander Yermolovich a224c5199b [LLD][LLVM] CG Graph profile using relocations
Currently when .llvm.call-graph-profile is created by llvm it explicitly encodes the symbol indices. This section is basically a black box for post processing tools. For example, if we run strip -s on the object files the symbol table changes, but indices in that section do not. In non-visible behavior indices point to wrong symbols. The visible behavior indices point outside of Symbol table: "invalid symbol index".

This patch changes the format by using R_*_NONE relocations to indicate the from/to symbols. The Frequency (Weight) will still be in the .llvm.call-graph-profile, but symbol information will be in relocation section. In LLD information from both sections is used to reconstruct call graph profile. Relocations themselves will never be applied.

With this approach post processing tools that handle relocations correctly work for this section also. Tools can add/remove symbols and as long as they handle relocation sections with this approach information stays correct.

Doing a quick experiment with clang-13.
The size went up from 107KB to 322KB, aggregate of all the input sections. Size of clang-13 binary is ~118MB. For users of -fprofile-use/-fprofile-sample-use the size of object files will go up slightly, it will not impact final binary size.

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D104080
2021-06-24 09:09:33 -07:00
RamNalamothu 167e7afcd5 Implement DW_CFA_LLVM_* for Heterogeneous Debugging
Add support in MC/MIR for writing/parsing, and DebugInfo.

This is part of the Extensions for Heterogeneous Debugging defined at
https://llvm.org/docs/AMDGPUDwarfExtensionsForHeterogeneousDebugging.html

Specifically the CFI instructions implemented here are defined at
https://llvm.org/docs/AMDGPUDwarfExtensionsForHeterogeneousDebugging.html#cfa-definition-instructions

Reviewed By: clayborg

Differential Revision: https://reviews.llvm.org/D76877
2021-06-14 08:51:50 +05:30
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
RamNalamothu 41f8b8e807 [MCAsmInfo] Support UsesCFIForDebug for targets with no exception handling
This change enables emitting CFI unwind information for debugging purpose
for targets with MCAsmInfo::ExceptionsType == ExceptionHandling::None.

Currently generating CFI unwind information is entangled with supporting
the exceptions, even when AsmPrinter explicitly recognizes that the unwind
tables are being generated as debug information.

In fact, the unwind information is not generated even if we specify
--force-dwarf-frame-section, unless exceptions are enabled. The LIT test
llvm/test/CodeGen/AMDGPU/debug_frame.ll demonstrates this behavior.

Enable this option for AMDGPU to prepare for future patches which add
complete CFI support.

Reviewed By: dblaikie, MaskRay

Differential Revision: https://reviews.llvm.org/D78778
2021-05-06 04:53:45 +05:30
Fangrui Song 7cac6a9d7a [MC] Add MCAsmParser::parseComma to improve diagnostics
llvm-mc will error "expected comma" instead of "unexpected token".
2021-05-04 14:13:19 -07:00
Fangrui Song 3d473ae72e [MC] Remove unneeded "in '.xxx' directive" from diagnostics
The directive name is not useful because the next line replicates the error line
which includes the directive.
2021-05-04 13:30:29 -07:00
Yuanfang Chen 80df56f7f9 Fix test case in b4a8c0ebb6 2021-03-18 15:55:48 -07:00
Yuanfang Chen b4a8c0ebb6 [LTO][MC] Discard non-prevailing defined symbols in module-level assembly
This is the alternative approach to D96931.

In LTO, for each module with inlineasm block, prepend directive ".lto_discard <sym>, <sym>*" to the beginning of the inline
asm.  ".lto_discard" is both a module inlineasm block marker and (optionally) provides a list of symbols to be discarded.

In MC while emitting for inlineasm, discard symbol binding & symbol
definitions according to ".lto_disard".

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D98762
2021-03-18 15:33:42 -07:00
Douglas Yung 6a7a208357 Add requirement for aarch64-registered-target to test change added in 42e3f97a9d. 2021-03-09 12:26:15 -08:00
Fangrui Song 42e3f97a9d [MC] Change ELFOSABI_NONE to ELFOSABI_GNU for SHF_GNU_RETAIN
GNU ld does not give SHF_GNU_RETAIN GC root semantics for ELFOSABI_NONE.
(https://sourceware.org/pipermail/binutils/2021-March/115581.html)

This allows GNU ld to interpret SHF_GNU_RETAIN and avoids a gold quirk
https://sourceware.org/bugzilla/show_bug.cgi?id=27490

Because ELFObjectWriter is in an anonymous namespace, I have to place
`markGnuAbi` in the parent MCObjectWriter.

Differential Revision: https://reviews.llvm.org/D97976
2021-03-09 09:59:47 -08:00
John Brawn bf3a271960 [CodeGen] Report a normal instead of fatal error for label redefinition
A symbol being redefined as a label is something that can happen as a result of
ordinary input, so it shouldn't cause a fatal error. Also adjust the error
message to match the one you get when a symbol is redefined as a variable.

Differential Revision: https://reviews.llvm.org/D98181
2021-03-09 10:54:41 +00:00
Fangrui Song bb6732cf62 [MC] Add parseEOL() overload and migrate some parseToken(AsmToken::EndOfStatement) to parseEOL()
For many directives, the following diagnostics

* `error: unexpected token`
* `error: unexpected token in '.abort' directive"`

are replaced with `error: expected newline`.

`unexpected token` may make the user think a different token is needed.
`expected newline` is clearer about the expected token.

For `in '...' directive`, the directive name is not useful because the next line
replicates the error line which includes the directive.
2021-03-06 17:45:23 -08:00
Fangrui Song e5eb3e3836 [MC] Parse end-of-line for .addrsig & .addrsig_sym 2021-03-06 16:26:27 -08:00
Fangrui Song fd785f98aa [MC] Parse end-of-line for .cfi_* directives
Otherwise MCAsmStreamer will emit duplicate newlines.
2021-03-06 16:20:55 -08:00
Fangrui Song d96af2ed2d [MC] Support .symver *, *, remove
As a resolution to https://sourceware.org/bugzilla/show_bug.cgi?id=25295 , GNU as
from binutils 2.35 supports the optional third argument for the .symver directive.

'remove' for a non-default version is useful:
`.symver def_v1, def@v1, remove` => def_v1 is not retained in the symbol table.
Previously the user has to strip the original symbol or specify a `local:`
version node in a version script to localize the symbol.

`.symver def, def@@v1, remove` and `.symver def, def@@@v1, remove` are supported
as well, though they are identical to `.symver def, def@@@v1`.

local/hidden are not useful so this patch does not implement them.
2021-03-06 15:23:02 -08:00
Fangrui Song 880c9c56c1 [MC] Allow .cfi_sections with empty section list
GNU as supports this. This mode silently ignores
.cfi_startproc/.cfi_endproc and .cfi_* in between.

Also drop a diagnostic `in '.cfi_sections' directive`: the diagnostic
already includes the line and it is clear the line is a `.cfi_sections` directive.
2021-02-25 22:29:49 -08:00
Fangrui Song 962b29d716 ELFObjectWriter: Don't sort non-local symbols
As we don't sort local symbols, don't sort non-local symbols.  This makes
non-local symbols appear in their register order, which matches GNU as. The
register order is nice in that you can write tests with interleaved CHECK
prefixes, e.g.

```
// CHECK: something about foo
.globl foo
foo:
// CHECK: something about bar
.globl bar
bar:
```

With the lexicographical order, the user needs to place lexicographical smallest
symbol first or keep CHECK prefixes in one place.
2021-02-13 10:32:27 -08:00
Fangrui Song 1f69355802 [test] Make ELF tests amenable to the order of non-local symbols 2021-02-12 21:00:42 -08:00