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.
The situation with inline asm/MC error reporting is kind of messy at the
moment. The errors from MC layout are not reliably propagated and users
have to specify an inlineasm handler separately to get inlineasm
diagnose. The latter issue is not a correctness issue but could be improved.
* Kill LLVMContext inlineasm diagnose handler and migrate it to use
DiagnoseInfo/DiagnoseHandler.
* Introduce `DiagnoseInfoSrcMgr` to diagnose SourceMgr backed errors. This
covers use cases like inlineasm, MC, and any clients using SourceMgr.
* Move AsmPrinter::SrcMgrDiagInfo and its instance to MCContext. The next step
is to combine MCContext::SrcMgr and MCContext::InlineSrcMgr because in all
use cases, only one of them is used.
* If LLVMContext is available, let MCContext uses LLVMContext's diagnose
handler; if LLVMContext is not available, MCContext uses its own default
diagnose handler which just prints SMDiagnostic.
* Change a few clients(Clang, llc, lldb) to use the new way of reporting.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D97449
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.
Without `-dwarf-version`, llvm-mc uses the default `MCContext::DwarfVersion` 4.
Without `-gdwarf-N`, Clang cc1as uses `clang::driver::ToolChain::GetDefaultDwarfVersion`
which is 4 on many toolchains. Note: `clang -c` can synthesize .debug_info without -g.
There is currently a MCParser warning upon `.file 0` and MCParser errors upon
`.loc 0` if the DWARF version is less than 5. This causes friction to the
following usage:
```
clang -S -g -gdwarf-5 a.c
// MC warning due to .file 0, MC error due to .loc 0
clang -c a.s
llvm-mc -filetype=obj a.s
```
My idea is that we can just upgrade `MCContext::DwarfVersion` to 5 upon
`.file 0` to make the above commands work.
The downside is that for an explicit version `clang -c -gdwarf-4 a.s`, it can be
argued that the new behavior drops the probably intended diagnostic. I think the
downside is small because in most cases DWARF version for an assembly action
should either match the original compile action or be omitted.
Ongoing discussion taking a similar action for GNU as: https://sourceware.org/pipermail/binutils/2021-January/114980.html
Differential Revision: https://reviews.llvm.org/D94882
Currently the integrated assembler only allows commas as the separator
between string arguments in .ascii. This patch adds support to using
space as separators and make IAS consistent with GNU assembler.
Link: https://github.com/ClangBuiltLinux/linux/issues/1196
Reviewed By: nickdesaulniers, jrtc27
Differential Revision: https://reviews.llvm.org/D91460
This is consistent with the resolution to power-of-2 alignments.
Otherwise, emitCodeAlignment and emitValueToAlignment cannot handle alignments
larger than 2**32 and will trigger assertion failure (PR35218).
Note: GNU as as of 2.35 will use 1 for such a large byte `.align`
This change implements pseudo probe encoding and emission for CSSPGO. Please see RFC here for more context: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s
Pseudo probes are in the form of intrinsic calls on IR/MIR but they do not turn into any machine instructions. Instead they are emitted into the binary as a piece of data in standalone sections. The probe-specific sections are not needed to be loaded into memory at execution time, thus they do not incur a runtime overhead.
**ELF object emission**
The binary data to emit are organized as two ELF sections, i.e, the `.pseudo_probe_desc` section and the `.pseudo_probe` section. The `.pseudo_probe_desc` section stores a function descriptor for each function and the `.pseudo_probe` section stores the actual probes, each fo which corresponds to an IR basic block or an IR function callsite. A function descriptor is stored as a module-level metadata during the compilation and is serialized into the object file during object emission.
Both the probe descriptors and pseudo probes can be emitted into a separate ELF section per function to leverage the linker for deduplication. A `.pseudo_probe` section shares the same COMDAT group with the function code so that when the function is dead, the probes are dead and disposed too. On the contrary, a `.pseudo_probe_desc` section has its own COMDAT group. This is because even if a function is dead, its probes may be inlined into other functions and its descriptor is still needed by the profile generation tool.
The format of `.pseudo_probe_desc` section looks like:
```
.section .pseudo_probe_desc,"",@progbits
.quad 6309742469962978389 // Func GUID
.quad 4294967295 // Func Hash
.byte 9 // Length of func name
.ascii "_Z5funcAi" // Func name
.quad 7102633082150537521
.quad 138828622701
.byte 12
.ascii "_Z8funcLeafi"
.quad 446061515086924981
.quad 4294967295
.byte 9
.ascii "_Z5funcBi"
.quad -2016976694713209516
.quad 72617220756
.byte 7
.ascii "_Z3fibi"
```
For each `.pseudoprobe` section, the encoded binary data consists of a single function record corresponding to an outlined function (i.e, a function with a code entry in the `.text` section). A function record has the following format :
```
FUNCTION BODY (one for each outlined function present in the text section)
GUID (uint64)
GUID of the function
NPROBES (ULEB128)
Number of probes originating from this function.
NUM_INLINED_FUNCTIONS (ULEB128)
Number of callees inlined into this function, aka number of
first-level inlinees
PROBE RECORDS
A list of NPROBES entries. Each entry contains:
INDEX (ULEB128)
TYPE (uint4)
0 - block probe, 1 - indirect call, 2 - direct call
ATTRIBUTE (uint3)
reserved
ADDRESS_TYPE (uint1)
0 - code address, 1 - address delta
CODE_ADDRESS (uint64 or ULEB128)
code address or address delta, depending on ADDRESS_TYPE
INLINED FUNCTION RECORDS
A list of NUM_INLINED_FUNCTIONS entries describing each of the inlined
callees. Each record contains:
INLINE SITE
GUID of the inlinee (uint64)
ID of the callsite probe (ULEB128)
FUNCTION BODY
A FUNCTION BODY entry describing the inlined function.
```
To support building a context-sensitive profile, probes from inlinees are grouped by their inline contexts. An inline context is logically a call path through which a callee function lands in a caller function. The probe emitter builds an inline tree based on the debug metadata for each outlined function in the form of a trie tree. A tree root is the outlined function. Each tree edge stands for a callsite where inlining happens. Pseudo probes originating from an inlinee function are stored in a tree node and the tree path starting from the root all the way down to the tree node is the inline context of the probes. The emission happens on the whole tree top-down recursively. Probes of a tree node will be emitted altogether with their direct parent edge. Since a pseudo probe corresponds to a real code address, for size savings, the address is encoded as a delta from the previous probe except for the first probe. Variant-sized integer encoding, aka LEB128, is used for address delta and probe index.
**Assembling**
Pseudo probes can be printed as assembly directives alternatively. This allows for good assembly code readability and also provides a view of how optimizations and pseudo probes affect each other, especially helpful for diff time assembly analysis.
A pseudo probe directive has the following operands in order: function GUID, probe index, probe type, probe attributes and inline context. The directive is generated by the compiler and can be parsed by the assembler to form an encoded `.pseudoprobe` section in the object file.
A example assembly looks like:
```
foo2: # @foo2
# %bb.0: # %bb0
pushq %rax
testl %edi, %edi
.pseudoprobe 837061429793323041 1 0 0
je .LBB1_1
# %bb.2: # %bb2
.pseudoprobe 837061429793323041 6 2 0
callq foo
.pseudoprobe 837061429793323041 3 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
.LBB1_1: # %bb1
.pseudoprobe 837061429793323041 5 1 0
callq *%rsi
.pseudoprobe 837061429793323041 2 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
# -- End function
.section .pseudo_probe_desc,"",@progbits
.quad 6699318081062747564
.quad 72617220756
.byte 3
.ascii "foo"
.quad 837061429793323041
.quad 281547593931412
.byte 4
.ascii "foo2"
```
With inlining turned on, the assembly may look different around %bb2 with an inlined probe:
```
# %bb.2: # %bb2
.pseudoprobe 837061429793323041 3 0
.pseudoprobe 6699318081062747564 1 0 @ 837061429793323041:6
.pseudoprobe 837061429793323041 4 0
popq %rax
retq
```
**Disassembling**
We have a disassembling tool (llvm-profgen) that can display disassembly alongside with pseudo probes. So far it only supports ELF executable file.
An example disassembly looks like:
```
00000000002011a0 <foo2>:
2011a0: 50 push rax
2011a1: 85 ff test edi,edi
[Probe]: FUNC: foo2 Index: 1 Type: Block
2011a3: 74 02 je 2011a7 <foo2+0x7>
[Probe]: FUNC: foo2 Index: 3 Type: Block
[Probe]: FUNC: foo2 Index: 4 Type: Block
[Probe]: FUNC: foo Index: 1 Type: Block Inlined: @ foo2:6
2011a5: 58 pop rax
2011a6: c3 ret
[Probe]: FUNC: foo2 Index: 2 Type: Block
2011a7: bf 01 00 00 00 mov edi,0x1
[Probe]: FUNC: foo2 Index: 5 Type: IndirectCall
2011ac: ff d6 call rsi
[Probe]: FUNC: foo2 Index: 4 Type: Block
2011ae: 58 pop rax
2011af: c3 ret
```
Reviewed By: wmi
Differential Revision: https://reviews.llvm.org/D91878
This change implements pseudo probe encoding and emission for CSSPGO. Please see RFC here for more context: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s
Pseudo probes are in the form of intrinsic calls on IR/MIR but they do not turn into any machine instructions. Instead they are emitted into the binary as a piece of data in standalone sections. The probe-specific sections are not needed to be loaded into memory at execution time, thus they do not incur a runtime overhead.
**ELF object emission**
The binary data to emit are organized as two ELF sections, i.e, the `.pseudo_probe_desc` section and the `.pseudo_probe` section. The `.pseudo_probe_desc` section stores a function descriptor for each function and the `.pseudo_probe` section stores the actual probes, each fo which corresponds to an IR basic block or an IR function callsite. A function descriptor is stored as a module-level metadata during the compilation and is serialized into the object file during object emission.
Both the probe descriptors and pseudo probes can be emitted into a separate ELF section per function to leverage the linker for deduplication. A `.pseudo_probe` section shares the same COMDAT group with the function code so that when the function is dead, the probes are dead and disposed too. On the contrary, a `.pseudo_probe_desc` section has its own COMDAT group. This is because even if a function is dead, its probes may be inlined into other functions and its descriptor is still needed by the profile generation tool.
The format of `.pseudo_probe_desc` section looks like:
```
.section .pseudo_probe_desc,"",@progbits
.quad 6309742469962978389 // Func GUID
.quad 4294967295 // Func Hash
.byte 9 // Length of func name
.ascii "_Z5funcAi" // Func name
.quad 7102633082150537521
.quad 138828622701
.byte 12
.ascii "_Z8funcLeafi"
.quad 446061515086924981
.quad 4294967295
.byte 9
.ascii "_Z5funcBi"
.quad -2016976694713209516
.quad 72617220756
.byte 7
.ascii "_Z3fibi"
```
For each `.pseudoprobe` section, the encoded binary data consists of a single function record corresponding to an outlined function (i.e, a function with a code entry in the `.text` section). A function record has the following format :
```
FUNCTION BODY (one for each outlined function present in the text section)
GUID (uint64)
GUID of the function
NPROBES (ULEB128)
Number of probes originating from this function.
NUM_INLINED_FUNCTIONS (ULEB128)
Number of callees inlined into this function, aka number of
first-level inlinees
PROBE RECORDS
A list of NPROBES entries. Each entry contains:
INDEX (ULEB128)
TYPE (uint4)
0 - block probe, 1 - indirect call, 2 - direct call
ATTRIBUTE (uint3)
reserved
ADDRESS_TYPE (uint1)
0 - code address, 1 - address delta
CODE_ADDRESS (uint64 or ULEB128)
code address or address delta, depending on ADDRESS_TYPE
INLINED FUNCTION RECORDS
A list of NUM_INLINED_FUNCTIONS entries describing each of the inlined
callees. Each record contains:
INLINE SITE
GUID of the inlinee (uint64)
ID of the callsite probe (ULEB128)
FUNCTION BODY
A FUNCTION BODY entry describing the inlined function.
```
To support building a context-sensitive profile, probes from inlinees are grouped by their inline contexts. An inline context is logically a call path through which a callee function lands in a caller function. The probe emitter builds an inline tree based on the debug metadata for each outlined function in the form of a trie tree. A tree root is the outlined function. Each tree edge stands for a callsite where inlining happens. Pseudo probes originating from an inlinee function are stored in a tree node and the tree path starting from the root all the way down to the tree node is the inline context of the probes. The emission happens on the whole tree top-down recursively. Probes of a tree node will be emitted altogether with their direct parent edge. Since a pseudo probe corresponds to a real code address, for size savings, the address is encoded as a delta from the previous probe except for the first probe. Variant-sized integer encoding, aka LEB128, is used for address delta and probe index.
**Assembling**
Pseudo probes can be printed as assembly directives alternatively. This allows for good assembly code readability and also provides a view of how optimizations and pseudo probes affect each other, especially helpful for diff time assembly analysis.
A pseudo probe directive has the following operands in order: function GUID, probe index, probe type, probe attributes and inline context. The directive is generated by the compiler and can be parsed by the assembler to form an encoded `.pseudoprobe` section in the object file.
A example assembly looks like:
```
foo2: # @foo2
# %bb.0: # %bb0
pushq %rax
testl %edi, %edi
.pseudoprobe 837061429793323041 1 0 0
je .LBB1_1
# %bb.2: # %bb2
.pseudoprobe 837061429793323041 6 2 0
callq foo
.pseudoprobe 837061429793323041 3 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
.LBB1_1: # %bb1
.pseudoprobe 837061429793323041 5 1 0
callq *%rsi
.pseudoprobe 837061429793323041 2 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
# -- End function
.section .pseudo_probe_desc,"",@progbits
.quad 6699318081062747564
.quad 72617220756
.byte 3
.ascii "foo"
.quad 837061429793323041
.quad 281547593931412
.byte 4
.ascii "foo2"
```
With inlining turned on, the assembly may look different around %bb2 with an inlined probe:
```
# %bb.2: # %bb2
.pseudoprobe 837061429793323041 3 0
.pseudoprobe 6699318081062747564 1 0 @ 837061429793323041:6
.pseudoprobe 837061429793323041 4 0
popq %rax
retq
```
**Disassembling**
We have a disassembling tool (llvm-profgen) that can display disassembly alongside with pseudo probes. So far it only supports ELF executable file.
An example disassembly looks like:
```
00000000002011a0 <foo2>:
2011a0: 50 push rax
2011a1: 85 ff test edi,edi
[Probe]: FUNC: foo2 Index: 1 Type: Block
2011a3: 74 02 je 2011a7 <foo2+0x7>
[Probe]: FUNC: foo2 Index: 3 Type: Block
[Probe]: FUNC: foo2 Index: 4 Type: Block
[Probe]: FUNC: foo Index: 1 Type: Block Inlined: @ foo2:6
2011a5: 58 pop rax
2011a6: c3 ret
[Probe]: FUNC: foo2 Index: 2 Type: Block
2011a7: bf 01 00 00 00 mov edi,0x1
[Probe]: FUNC: foo2 Index: 5 Type: IndirectCall
2011ac: ff d6 call rsi
[Probe]: FUNC: foo2 Index: 4 Type: Block
2011ae: 58 pop rax
2011af: c3 ret
```
Reviewed By: wmi
Differential Revision: https://reviews.llvm.org/D91878
Previously these directives were always interpreted as having an extra
blank line after them.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D92612
I was trying to add .cfi_ annotations to assembly code in the FreeBSD
kernel and changed a macro that then resulted in incorrectly nested
directives. However, clang's diagnostics said the error was happening at
<unknown>:0. This addresses one of the TODOs added in D51695.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D89787
A SMLoc allows MCStreamer to report location-aware diagnostics, which
were previously done by adding SMLoc to various methods (e.g. emit*) in an ad-hoc way.
Since the file:line is most important, the column is less important and
the start token location suffices in many cases, this patch reverts
b7e7131af2
```
// old
symbol-binding-changed.s:6:8: error: local changed binding to STB_GLOBAL
.globl local
^
// new
symbol-binding-changed.s:6:1: error: local changed binding to STB_GLOBAL
.globl local
^
```
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D90511
For `.reloc offset, *, *`, currently offset can be a constant or symbol.
This patch makes it support any expression which can be folded to sym+constant.
Reviewed By: stefanp
Differential Revision: https://reviews.llvm.org/D83751
Compiling assembly files when newlines are reduced to line markers within a `.macro` context will generate wrong information in `.debug_line` section.
This patch fixes this issue by evaluating line markers within the macro scope but not when they are used and evaluated.
Reviewed By: probinson
Differential Revision: https://reviews.llvm.org/D80381
According to DWARF standard, is_stmt is a global flag; when set or cleared it should affect subsequent .loc directives.
However llvm assembler handled is_stmt differently: it forced all locations to have is_stmt=1 unless is_stmt was specified explicitly as 0.
The fix utilizes current DWARF state flags to compute correct is_stmt values.
See https://bugs.llvm.org/show_bug.cgi?id=45529 for a detailed issue description.
Reviewers: arsenm, probinson, enderby
Differential Revision: https://reviews.llvm.org/D78102
* Reorganize tests and add coverage
* Improve diagnostic testing
* Make assert() tests more relevant
* Rename tests to macro-* or altmacro-*
This is not NFC because a (previously untested) diagnostic message is changed.
Summary:
Dollar signed prefixed integers were not allowed by the AsmParser to be
used as Identifiers, differing from the GNU assembler behavior.
This patch updates the parsing of Identifiers to consider such cases as
valid, where the identifier string includes the $ prefix itself. As the
Lexer currently splits these occurrences into separate tokens, those
need to be combined by the AsmParser itself.
Reviewers: efriedma, chill
Reviewed By: efriedma
Subscribers: sdardis, hiraditya, jrtc27, atanasyan, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75111
Summary: ParsingInlineAsm was a misleading name. These values are only set for MS-style inline assembly.
Reviewed By: rnk
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D75198
Summary:
Many directives are unavailable, and support for others may be limited.
This first draft has preliminary support for:
- conditional directives (including errors),
- data allocation (unsigned types up to 8 bytes, and ALIGN),
- equates/variables (numeric and text),
- and procedure directives (without parameters),
as well as COMMENT, ECHO, INCLUDE, INCLUDELIB, PUBLIC, and EXTERN. Text variables (aka text macros) are expanded in-place wherever the identifier occurs.
We deliberately ignore all ml.exe processor directives.
Prominent features not yet supported:
- structs
- macros (both procedures and functions)
- procedures (with specified parameters)
- substitution & expansion operators
Conditional directives are complicated by the fact that "ifdef rax" is a valid way to check if a file is being assembled for a 64-bit x86 processor; we add support for "ifdef <register>" in general, which requires adding a tryParseRegister method to all MCTargetAsmParsers. (Some targets require backtracking in the non-register case.)
Reviewers: rnk, thakis
Reviewed By: thakis
Subscribers: kerbowa, merge_guards_bot, wuzish, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, mgorny, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Jim, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72680
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
GCC will accept any case for assembler directives.
For example ".abort" and ".ABORT" (even ".aBoRt")
are equivalent.
https://sourceware.org/binutils/docs/as/Pseudo-Ops.html#Pseudo-Ops
"The names are case insensitive for most targets,
and usually written in lower case."
Change llvm-mc to accept any case for generic directives
or aliases of those directives.
This for Bugzilla #39527.
Differential Revision: https://reviews.llvm.org/D72686
Summary:
Extend D71677 to apply to all branch-target operands, rather than special-casing call instructions.
Also add a regression test for llvm.org/PR44272, since this finishes fixing it.
Reviewers: thakis, rnk
Reviewed By: thakis
Subscribers: merge_guards_bot, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D72417
`APFLoat::convertFromString` returns `Expected` result, which must be
"checked" if the LLVM_ENABLE_ABI_BREAKING_CHECKS preprocessor flag is
set.
To mark an `Expected` result as "checked" we must consume the `Error`
within.
In many cases, we are only interested in knowing if an error occured,
without the need to examine the error info. This is achieved, easily,
with the `errorToBool()` API.
Summary:
Amend MS offset operator implementation, to more closely fit with its MS counterpart:
1. InlineAsm: evaluate non-local source entities to their (address) location
2. Provide a mean with which one may acquire the address of an assembly label via MS syntax, rather than yielding a memory reference (i.e. "offset asm_label" and "$asm_label" should be synonymous
3. address PR32530
Based on http://llvm.org/D37461
Fix broken test where the break appears unrelated.
- Set up appropriate memory-input rewrites for variable references.
- Intel-dialect assembly printing now correctly handles addresses by adding "offset".
- Pass offsets as immediate operands (using "r" constraint for offsets of locals).
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D71436
Summary:
This is documented as the appropriate template modifier for call operands.
Fixes PR44272, and adds a regression test.
Also adds support for operand modifiers in Intel-style inline assembly.
Reviewers: rnk
Reviewed By: rnk
Subscribers: merge_guards_bot, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D71677
Summary:
Implement support for hexadecimal escape sequences to match how GNU 'as'
handles them. I.e., read all hexadecimal characters and truncate to the
lower 16 bits.
Reviewers: nickdesaulniers, jcai19
Subscribers: llvm-commits, hiraditya
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68598
llvm-svn: 374018
It broke MC/AsmParser/directive_ascii.s on all bots:
Assertion failed: (Index < Length && "Invalid index!"), function operator[],
file ../../llvm/include/llvm/ADT/StringRef.h, line 243.
llvm-svn: 373898
Summary:
Implement support for hexadecimal escape sequences to match how GNU 'as'
handles them. I.e., read all hexadecimal characters and truncate to the
lower 16 bits.
Reviewers: nickdesaulniers
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68483
llvm-svn: 373888
Summary:
This patch keeps track of MCSymbols created for blocks that were
referenced in inline asm. It prevents creating a new symbol which
doesn't refer to the block.
Inline asm may have a reference to a label. The asm parser however
doesn't recognize it as a label and tries to create a new symbol. The
result being that instead of the original symbol (e.g. ".Ltmp0") the
parser replaces it in the inline asm with the new one (e.g. ".Ltmp00")
without updating it in the symbol table. So the machine basic block
retains the "old" symbol (".Ltmp0"), but the inline asm uses the new one
(".Ltmp00").
Reviewers: nickdesaulniers, craig.topper
Subscribers: nathanchance, javed.absar, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65304
llvm-svn: 368477
This patch replaces a TODO comment with a call to `report_fatal_error`.
The path that reaches the added call to `report_fatal_error` manifestly
dereferences a null pointer.
llvm-svn: 368048
llvm-mc or clang with -g normally produces debug info describing the
assembler source itself; however, if that source already contains some
.file/.loc directives, we should instead emit the debug info described
by those directives. For certain assembler sources seen in the wild
(particularly in the Chrome build) this was causing a crash due to
incorrect assumptions about legal sequences of assembler source text.
Fixes PR38994.
Differential Revision: https://reviews.llvm.org/D63573
llvm-svn: 364039
This provides the correct file path for the original source, rather
than the preprocessed source.
Part of the fix for PR41839.
Differential Revision: https://reviews.llvm.org/D62074
llvm-svn: 361248
This patch adds an XCOFF triple object format type into LLVM.
This XCOFF triple object file type will be used later by object file and assembly generation for the AIX platform.
Differential Revision: https://reviews.llvm.org/D58930
llvm-svn: 355989
This was sometimes causing clang or llvm-mc to crash, and in other
cases could emit a bogus DWARF line-table header. I did an interim
patch in r352541; this patch should be a cleaner and more complete
fix, and retains the test.
Addresses PR40538.
Differential Revision: https://reviews.llvm.org/D58750
llvm-svn: 355226
Summary:
Before r349976, MC ignored such directives when producing an object file
and asserted when re-producing textual assembly output. I turned this
assertion into a hard error in both cases in r349976, but this makes it
unnecessarily difficult to write a single assembly file that supports
both MachO and other object formats that support .file. A user reported
this as PR40578, and we decided to go back to ignoring the directive.
Fixes PR40578
Reviewers: mstorsjo
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57772
llvm-svn: 353218
N_FUNC_COLD is a new MachO symbol attribute. It's a hint to the linker
to order a symbol towards the end of its section, to improve locality.
Example:
```
void a1() {}
__attribute__((cold)) void a2() {}
void a3() {}
int main() {
a1();
a2();
a3();
return 0;
}
```
A linker that supports N_FUNC_COLD will order _a2 to the end of the text
section. From `nm -njU` output, we see:
```
_a1
_a3
_main
_a2
```
Differential Revision: https://reviews.llvm.org/D57190
llvm-svn: 352227
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary:
It does so using a simple nesting stack, and gives clear errors upon
violation. This is unique to wasm, since most CPUs do not have
any nested constructs.
Had to add an end of file check to the general assembler for this.
Note: if/else/end instructions are not currently supported in our
tablegen defs, so these tests will be enabled in a follow-up.
They already pass the nesting check.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55797
llvm-svn: 350078
Summary:
The "single parameter" .file directive appears to be an ELF-only feature
that is intended to insert the main source filename into the string
table table.
I noticed that if you assemble an ELF .s file for COFF, typically it
will assert right away on a .file directive near the top of the file. My
first change was to make this emit a proper error in the asm parser so
that we don't assert so easily.
However, COFF actually does have some support for this directive, and if
you emit an object file, llvm-mc does not assert. When emitting a COFF
object, MC will take those file names and create "debug" symbol table
entries for them. I'm not familiar with these kinds of symbol table
entries, and I'm not aware of any users of them, but @compnerd added
them a while ago. They don't introduce absolute paths, and most main
source file paths are short enough that this extra entry shouldn't cause
any problems, so I enabled the flag in MCAsmInfoCOFF that indicates that
it's supported.
This has the side effect of adding an extra debug symbol to every object
produced by clang, which is a pretty big functional change. My question
is, should we keep the functionality or remove it in the name of symbol
table minimalism?
Reviewers: mstorsjo, compnerd
Subscribers: hiraditya, compnerd, llvm-commits
Differential Revision: https://reviews.llvm.org/D55900
llvm-svn: 349976
- When signing return addresses with -msign-return-address=<scope>{+<key>},
either the A key instructions or the B key instructions can be used. To
correctly authenticate the return address, the unwinder/debugger must know
which key was used to sign the return address.
- When and exception is thrown or a break point reached, it may be necessary to
unwind the stack. To accomplish this, the unwinder/debugger must be able to
first authenticate an the return address if it has been signed.
- To enable this, the augmentation string of CIEs has been extended to allow
inclusion of a 'B' character. Functions that are signed using the B key
variant of the instructions should have and FDE whose associated CIE has a 'B'
in the augmentation string.
- One must also be able to preserve these semantics when first stepping from a
high level language into assembly and then, as a second step, into an object
file. To achieve this, I have introduced a new assembly directive
'.cfi_b_key_frame ', that tells the assembler the current frame uses return
address signing with the B key.
- This ensures that the FDE is associated with a CIE that has 'B' in the
augmentation string.
Differential Revision: https://reviews.llvm.org/D51798
llvm-svn: 349895
Currently, expressions like
.reloc 1f, R_MIPS_JALR, foo
1: nop
are not allowed, ie. an offset in .reloc can only be absolute value.
This patch adds support for labels as offsets.
If offset is a forward declared label, MCObjectStreamer keeps the fixup locally
and adds it to the fixups vector after the label (and its offset) is defined.
label+number is not supported yet.
Differential revision: https://reviews.llvm.org/D53990
llvm-svn: 347397
Summary:
This is to replace the ELFAsmParser that WebAssembly was using, which
so far was a stub that didn't do anything, and couldn't work correctly
with wasm.
This new class is there to implement generic directives related to
wasm as a binary format. Wasm target specific directives are still
parsed in WebAssemblyAsmParser as before. The two classes now
cooperate more correctly too.
Also implemented .result which was missing. Any unknown directives
will now result in errors.
Reviewers: dschuff, sbc100
Subscribers: mgorny, jgravelle-google, eraman, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54360
llvm-svn: 346700
Summary:
This renames the IsParsingMSInlineAsm member variable of AsmLexer to
LexMasmIntegers and moves it up to MCAsmLexer. This is the only behavior
controlled by that variable. I added a public setter, so that it can be
set from outside or from the llvm-mc command line. We may need to
arrange things so that users can get this behavior from clang, but
that's future work.
I also put additional hex literal lexing functionality under this flag
to fix PR32973. It appears that this hex literal parsing wasn't intended
to be enabled in non-masm-style blocks.
Now, masm integers (0b1101 and 0ABCh) work in __asm blocks from clang,
but 0b label references work when using .intel_syntax in standalone .s
files.
However, 0b label references will *not* work from __asm blocks in clang.
They will work from GCC inline asm blocks, which it sounds like is
important for Crypto++ as mentioned in PR36144.
Essentially, we only lex masm literals for inline asm blobs that use
intel syntax. If the .intel_syntax directive is used inside a gnu-style
inline asm statement, masm literals will not be lexed, which is
compatible with gas and llvm-mc standalone .s assembly.
This fixes PR36144 and PR32973.
Reviewers: Gerolf, avt77
Subscribers: eraman, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D53535
llvm-svn: 345189
This avoids a crash (with asserts) or bad codegen (without asserts)
in Dwarf streamer later on. This patch fixes this condition in
MCStreamer and propogates SMLoc down when it's available with an
added bonus of source locations for those specific types of errors.
Further patches could use similar improvements as currently most
non-Windows CFI directives lack an SMLoc parameter.
Modified an existing test to verify source location propogation and
added an object-file version of it to verify that it does not crash in
addition to a standalone test to only ensure it does not crash.
Differential Revision: https://reviews.llvm.org/D51695
llvm-svn: 344781
The following instruction:
> str q28, [x0, #1*6*4*@]
contains a @ which is parsed as an empty symbol. The parser returns true
but has no error, so the assembler continues by ignoring the
instruction.
Differential Revision: https://reviews.llvm.org/D52645
llvm-svn: 343961
The Lexer doesn't use this state itself. It is only set and used by AsmParser so it seems like it should just be part of AsmParser.
Differential Revision: https://reviews.llvm.org/D52515
llvm-svn: 343027
The main use case for this directive is to allow assembly writers to
write their own FPO data strings without going through the .cv_fpo*
directive family.
I'm experimenting with different RPN programs to fix PR38857, and I
figured I should go ahead and make this directive permanent.
llvm-svn: 341712
Summary:
For assembly input files, generate debug info even when the .file
directive is present, provided it does not include a file-number
argument. Fixes PR38695.
Reviewers: probinson, sidneym
Subscribers: aprantl, hiraditya, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D51315
llvm-svn: 340839
Summary:
Handle the case IDVal is an empty string.
This bug was uncovered by a LLVM MC Assembler Protocol Buffer
Fuzzer for the RISC-V assembly language.
Reviewers: rnk
Reviewed By: rnk
Subscribers: rnk, niravd, pcc, peter.smith, asb, grosbach, llvm-commits, bcain, kito-cheng, shiva0217, rogfer01, PkmX
Differential Revision: https://reviews.llvm.org/D50808
llvm-svn: 340678
Allow the comparison of x86 registers in the evaluation of assembler
directives. This generalizes and simplifies the extension from r334022
to catch another case found in the Linux kernel.
Reviewers: rnk, void
Reviewed By: rnk
Subscribers: hiraditya, nickdesaulniers, llvm-commits
Differential Revision: https://reviews.llvm.org/D50795
llvm-svn: 339895
This support was partial and temporary. Now that we have
wasm object file support its no longer needed.
Differential Revision: https://reviews.llvm.org/D48744
llvm-svn: 337222
DWARF v5 explicitly represents file #0 in the line table. Prior
versions did not, so ".loc 0" is still an error in those cases.
Differential Revision: https://reviews.llvm.org/D48452
llvm-svn: 335350
In some cases, for example when compiling a preprocessed file, the
front-end is not able to provide an MD5 checksum for all files. When
that happens, omit the MD5 checksums from the final DWARF, because
DWARF doesn't have a way to indicate that some but not all files have
a checksum.
When assembling a .s file, and some but not all .file directives
provide an MD5 checksum, issue a warning and don't emit MD5 into the
DWARF.
Fixes PR37623.
Differential Revision: https://reviews.llvm.org/D48135
llvm-svn: 334710
On targets like Arm some relaxations may only be performed when certain
architectural features are available. As functions can be compiled with
differing levels of architectural support we must make a judgement on
whether we can relax based on the MCSubtargetInfo for the function. This
change passes through the MCSubtargetInfo for the function to
fixupNeedsRelaxation so that the decision on whether to relax can be made
per function. In this patch, only the ARM backend makes use of this
information. We must also pass the MCSubtargetInfo to applyFixup because
some fixups skip error checking on the assumption that relaxation has
occurred, to prevent code-generation errors applyFixup must see the same
MCSubtargetInfo as fixupNeedsRelaxation.
Differential Revision: https://reviews.llvm.org/D44928
llvm-svn: 334078
Summary:
Allow extended parsing of variable assembler assignment syntax and modify X86 to permit
VAR = register assignment. As we emit these as .set directives when possible, we inline
such expressions in output assembly.
Fixes PR37425.
Reviewers: rnk, void, echristo
Reviewed By: rnk
Subscribers: nickdesaulniers, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D47545
llvm-svn: 334022
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46290
llvm-svn: 331272
Teach AsmParser to check with Assembler for when evaluating constant
expressions. This improves the handing of preprocessor expressions
that must be resolved at parse time. This idiom can be found as
assembling-time assertion checks in source-level assemblers. Note that
this relies on the MCStreamer to keep sufficient tabs on Section /
Fragment information which the MCAsmStreamer does not. As a result the
textual output may fail where the equivalent object generation would
pass. This can most easily be resolved by folding the MCAsmStreamer
and MCObjectStreamer together which is planned for in a separate
patch.
Currently, this feature is only enabled for assembly input, keeping IR
compilation consistent between assembly and object generation.
Reviewers: echristo, rnk, probinson, espindola, peter.smith
Reviewed By: peter.smith
Subscribers: eraman, peter.smith, arichardson, jyknight, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D45164
llvm-svn: 331218
Fangrui Song