When generating XCOFF, the compiler generates a csect with an internal
name. Each function results in a label within the csect. This patch
replaces the internal name ".text" with an empty string "". This avoids
adding special code to handle a function text() in the source file, and
works better with some XCOFF tools that are confused when the csect and
the first function have the same address.
Reviewed By: hubert.reinterpretcast
Differential Revision: https://reviews.llvm.org/D154854
'?' is a valid token in our downstream target. There seem to be no way
to do target-specific lexing, so just add make AsmParser recognize it.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D154202
Annotation attributes may be attached to a function to mark it with
custom data that will be contained in the final Wasm file. The
annotation causes a custom section named
"func_attr.annotate.<name>.<arg0>.<arg1>..." to be created that will
contain each function's index value that was marked with the annotation.
A new patchable relocation type for function indexes had to be created so
the custom section could be updated during linking.
Reviewed By: sbc100
Differential Revision: https://reviews.llvm.org/D150803
I found that the newly added member variables, "EmitCompactUnwindNonCanonical" were not initialized in the constructor, but other member variables were initialized. The behavior seems to need to be consistent to improve code.
Reviewed By: oontvoo
Differential Revision: https://reviews.llvm.org/D154472
This patch extends support of the option `-frecord-command-line` to XCOFF. XCOFF doesn’t have custom sections like ELF, so the command line data is emitted to a .info section instead. A C_INFO symbol is generated with the .info section to preserve the command line data past the link step. Multiple command lines are separated by newlines and null bytes. The command line data can be retrieved on AIX with command `what file_name`.
Reviewed By: scott.linder
Differential Revision: https://reviews.llvm.org/D153600
IAS was enabled on AIX in Clang. Also make sure to follow up with the part of the
diff (https://reviews.llvm.org/D150758) that was removed to enable support in the
backend as well.
Reviewed By: shchenz
Differential Revision: https://reviews.llvm.org/D154686
There was a bug in a code that pre-populated line string for a case where parts
of .debug_line are not processed by BOLT, but copied as raw data. We were not
switching sections. This resulted in parts of the binary being over-written with
debug data.
Reviewed By: maksfb
Differential Revision: https://reviews.llvm.org/D154544
This patch adds support for the ADA (associated data area), doing the following:
-Creates the ADA table to handle displacements
-Emits the ADA section in the SystemZAsmPrinter
-Lowers the ADA_ENTRY node into the appropriate load instruction
Differential Revision: https://reviews.llvm.org/D153788
Summary: Currently, if there are multiple definitions of the same symbol declared has weak linkage, the linker may choose the wrong one when they are compiled with integrated-as. This patch fixes the issue. If the target symbol is a weak label we must not attempt to resolve the fixup directly. Emit a relocation and leave resolution of the final target address to the linker.
Reviewed By: shchenz
Differential Revision: https://reviews.llvm.org/D153839
Conventionally, parsing methods return false on success and true on
error. However, directive parsing methods need a third state: the
directive is not target specific. AsmParser::parseStatement detected
this case by using a fragile heuristic: if the target parser did not
consume any tokens, the directive is assumed to be not target-specific.
Some targets fail to follow the convention: they return success after
emitting an error or do not consume the entire line and return failure
on successful parsing. This was partially worked around by checking for
pending errors in parseStatement.
This patch tries to improve the situation by introducing parseDirective
method that returns ParseStatus -- three-state class. The new method
should eventually replace the old one returning bool.
ParseStatus is intentionally implicitly constructible from bool to allow
uses like `return Error(Loc, "message")`. It also has a potential to
replace OperandMatchResulTy as it is more convenient to use due to the
implicit construction from bool and more type safe.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D154101
`MCExpr::evaluateAsAbsolute` has a longstanding bug. When the MCAssembler is
non-null and the MCAsmLayout is null, it may incorrectly fold A-B even if A and
B are separated by a linker-relaxable instruction. This behavior can suppress
some ADD/SUB relocations and lead to wrong results if the linker performs
relaxation.
To fix the bug, ensure that linker-relaxable instructions only appear at the end
of an MCDataFragment, thereby making them terminate the fragment. When computing
A-B, suppress folding if A and B are separated by a linker-relaxable
instruction.
* `.subsection` now correctly give errors for non-foldable expressions.
* gen-dwarf.s will pass even if we add back the .debug_line or .eh_frame/.debug_frame code from D150004
* This will fix suppressed relocation when we add R_RISCV_SET_ULEB128/R_RISCV_SUB_ULEB128.
In the future, we should investigate the desired behavior for
`MCExpr::evaluateAsAbsolute` when both MCAssembler and MCAsmLayout are non-null.
(Note: MCRelaxableFragment is only for assembler-relaxation. If we ever need
linker-relaxable MCRelaxableFragment, we would need to adjust RISCVMCExpr.cpp
(D58943/D73211).)
Depends on D153096
Differential Revision: https://reviews.llvm.org/D153097
- Creates the ADA table to handle displacements
- Emits the ADA section in the SystemZAsmPrinter
- Lowers the ADA_ENTRY node into the appropriate load instruction
Differential Revision: https://reviews.llvm.org/D153788
to help debug and report better diagnostics for functions like
relaxDwarfCallFrameFragment (D153167).
In MCStreamer, some emitCFI* functions already take a SMLoc argument. Add a
SMLoc argument to the remaining functions that generate a MCCFIInstruction.
Due to Mach-O's .subsections_via_symbols mechanism, non-private labels cannot
appear between .cfi_startproc/.cfi_endproc. Compilers do not produce such
labels, but hand-written assembly may. Give an error. Unfortunately,
emitDwarfAdvanceFrameAddr generated MCExpr doesn't have location
informatin.
Note: evaluateKnownAbsolute is to force folding A-B to a constant even if A and
B are separate by a non-private label. The function is a workaround for some
Mach-O assembler issues and should generally be avoided.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D153167
When emitting a debug_frame section, it contains a named symbol.
> echo "void foo(void) {}" | clang -arch arm64 -ffreestanding -g -c -o \
/tmp/test.o -x c -
> nm /tmp/test.o -s __DWARF __debug_frame
0000000000000200 s ltmp1
There are no such symbols emitted in any of the other DWARF sections,
this is because when the __debug_frame section is created, it doesn't
get a `BeginSymName` and so it creates a named symbol, such as `ltmp1`
and emits it when we switch to the section in MCDwarf.cpp.
This patch fixes the above issue.
Differential Revision: https://reviews.llvm.org/D153484
When emitting a debug_frame section, it contains a named symbol.
> echo "void foo(void) {}" | clang -arch arm64 -ffreestanding -g -c -o \
/tmp/test.o -x c -
> nm /tmp/test.o -s __DWARF __debug_frame
0000000000000200 s ltmp1
There are no such symbols emitted in any of the other DWARF sections,
this is because when the __debug_frame section is created, it doesn't
get a `BeginSymName` and so it creates a named symbol, such as `ltmp1`
and emits it when we switch to the section in MCDwarf.cpp.
This patch fixes the above issue.
Differential Revision: https://reviews.llvm.org/D153484
SubtargetFeature.h is currently part of MC while it doesn't depend on
anything in MC. Since some LLVM components might have the need to work
with target features without necessarily needing MC, it might be
worthwhile to move SubtargetFeature.h to a different location. This will
reduce the dependencies of said components.
Note that I choose TargetParser as the destination because that's where
Triple lives and SubtargetFeatures feels related to that.
This issues came up during a JITLink review (D149522). JITLink would
like to avoid a dependency on MC while still needing to store target
features.
Reviewed By: MaskRay, arsenm
Differential Revision: https://reviews.llvm.org/D150549
In preparation for removing the `#include "llvm/ADT/StringExtras.h"`
from the header to source file of `llvm/Support/Error.h`, first add in
all the missing includes that were previously included transitively
through this header.
D152340 has split WinCOFFObjectWriter to WinCOFFWriter. This patch adds
another WinCOFFWriter as DwoWriter to write Dwo sections to dwo file.
Driver options are also updated accordingly to support -gsplit-dwarf in
CL mode.
e.g. $ clang-cl -c -gdwarf -gsplit-dwarf foo.c
Like what -gsplit-dwarf did in ELF, using this option will create DWARF object
(.dwo) file. DWARF debug info is split between COFF object and DWARF object
file. It can reduce the executable file size especially for large project.
Reviewed By: skan, MaskRay
Differential Revision: https://reviews.llvm.org/D152785
Compiler-generated static symbols, such as the global initializers, can shared the same name and can coexist in the binary. As a result, their pseudo probes are all kept in the binary too. This could cause multiple call probes decoded against one callsite, as probes are decoded against there owning functions by name. I'm temporarily disabling an assert to keep the debug build green until we have a better fix.
Reviewed By: wenlei
Differential Revision: https://reviews.llvm.org/D153588
On AArch64, object files may be greater than 2^32 bytes. If an
offset is greater than the max value of a 32-bit unsigned integer,
LLVM silently truncates the offset. Instead, make it return an
error.
Differential Revision: https://reviews.llvm.org/D153494
This workaround appears to apply with gold<2.34 -O2/-O3 (linker -O2, not
compiler driver -O2). This used to be more visible as we used -Wl,-O3 in
CMake, but the option is generally not recommended and has been removed
by d63016a86548e8231002a760bbe9eb817cd1eb00 (Dec 2021).
This finishes a workaround removal work started by D64327 (2019).
Link: https://github.com/llvm/llvm-project/issues/45269
When the MCAssembler is non-null and the MCAsmLayout is null, we can fold A-B
when
* A and B are in the same fragment, or
* A's fragment suceeds B's fragment, and they are not separated by non-data fragments (D69411)
This patch allows folding when A's fragment precedes B's fragment so
that `9997b - . == 0` below can be evaluated as true:
```
nop
.arch_extension sec
9997:nop
// old behavior: error: expected absolute expression
.if 9997b - . == 0
.endif
```
Add a case to llvm/test/MC/ARM/directive-if-subtraction.s.
Note: for MCAsmStreamer, we cannot evaluate `.if . - 9997b == 0` at parse
time due to MCAsmStreamer::getAssemblerPtr returning nullptr (D45164).
Some Darwin tests check that this folding does not work. Add `.p2align 2` to
block some label difference folding or adjust the tests.
Reviewed By: nickdesaulniers
Differential Revision: https://reviews.llvm.org/D153096
The COFFAsmParser (to my surprise) didn't support the .pushsection and
.popsection directives. These directives aren't directly useful, however for
frontends that have inline asm support this is really useful. Rust in
particular, has support for inline asm, which can be used together with these
directives to "emulate" features like static generics. This patch adds support
for the two mentioned directives.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D152085
As mentioned by commit c5d38924dc6688c15b3fa133abeb3626e8f0767c (Apr 2020),
PC-relative entries avoid dynamic relocations and can therefore make the
section read-only.
This is similar to D78082 and D78590. We cannot commit to support
compiler/runtime built at different versions, so just don't play with versions.
For Mach-O support (incomplete yet), we use non-temporary `lxray_fn_idx[0-9]+`
symbols. Label differences are represented as a pair of UNSIGNED and SUBTRACTOR
relocations. The SUBTRACTOR external relocation requires r_extern==1 (needs to
reference a symbol table entry) which can be satisfied by `lxray_fn_idx[0-9]+`.
A `lxray_fn_idx[0-9]+` symbol also serves as the atom for this dead-strippable
section (follow-up to commit b9a134aa629de23a1dcf4be32e946e4e308fc64d).
Differential Revision: https://reviews.llvm.org/D152661
This patch adds support for the TLS local-exec access model on AIX to allow
for the ability to generate the 64-bit (specifically, non-optimized) code sequence.
For this patch in particular, the sequence that is generated involves a load of the
variable offset, followed by an add of the loaded variable offset to r13 (which is
thread pointer, respectively). This code sequence looks like the following:
```
ld reg1,var[TC](2)
add reg2, reg1, r13 // r13 contains the thread pointer
```
The TOC (.tc pseudo-op) entries generated in the assembly files are also
changed where we add the @le relocation for the variable offset.
Differential Revision: https://reviews.llvm.org/D149722
Fixes: c26c5e47ab9ca60835f191c90fa751e9a7dd0f3d (essentially a no-op)
The newly created MCDataFragment should inherit Atom (see
MCMachOStreamer::finishImpl). To the best of my knowledge, this change cannot be
tested at present, but this is important to ensure
MCExpr.cpp:AttemptToFoldSymbolOffsetDifference gives the same result in case we
evaluate the expression again with a MCAsmLayout.
In the following case,
```
.section __DATA,xray_instr_map
lxray_sleds_start1:
.space 16
Lxray_sleds_end1:
.section __DATA,xray_fn_idx
.quad (Lxray_sleds_end1-lxray_sleds_start1)>>4 // can be folded without a MCAsmLayout
```
When we have a MCAsmLayout, without this change, evaluating
(Lxray_sleds_end1-lxray_sleds_start1)>>4 again will fail due to
`FA->getAtom() == nullptr && FB.getAtom() != nullptr` in
MachObjectWriter::isSymbolRefDifferenceFullyResolvedImpl, called by
AttemptToFoldSymbolOffsetDifference.
When the MCAssembler is non-null and the MCAsmLayout is null, we can fold A-B
in these additional cases:
* when A is a pending label (will be reassigned to a real fragment in flushPendingLabels())
* A and B are separated by a MCFillFragment with a constant size
If FA == FB, we can use SA.getOffset() - SB.getOffset() even if FA is
not a MCDataFragment, as the only case this can be problematic
(different offsets for a variable-size fragment) is invalid/unreachable.
If FA != FB, the `if (FI->getKind() != MCFragment::FT_Data)` check below
can bail out correctly.
This change will help Mach-O fold more expressions. For ELF this is NFC,
unless evaluateFixup has a bug that would evaluate an expression
differently.
The newly created MCDataFragment should inherit Atom (see
MCMachOStreamer::finishImpl). I cannot think of a case to test the
behavior, but this is one step towards folding the Mach-O label
difference below and making Mach-O more similar to ELF.
```
.section __DATA,xray_instr_map
lxray_sleds_start1:
.space 16
Lxray_sleds_end1:
.section __DATA,xray_fn_idx
.quad (Lxray_sleds_end1-lxray_sleds_start1)>>4 // error: expected relocatable expression // Mach-O
```
* Add the SHF_LINK_ORDER flag so that the .pseudo_probe section is discarded when the associated text section is discarded.
* Add unique ID so that with `clang -ffunction-sections -fno-unique-section-names`, there is one separate .pseudo_probe for each text section (disambiguated by `.section ....,unique,id` in assembly)
The changes allow .pseudo_probe GC even if we don't place instrumented functions
in an IR comdat (see `getOrCreateFunctionComdat` in SampleProfileProbe.cpp).
Reviewed By: hoy
Differential Revision: https://reviews.llvm.org/D153189
If `evaluateAsAbsolute(Value, Layout.getAssembler())` returns true, we
know the address delta is a constant and can suppress relocations
(usually SET6/SUB6).
While here, replace two evaluateKnownAbsolute calls (subtle; avoid if possible)
with evaluateAsAbsolute.
For the out-of-range error, MCConstantExpr doesn't have a location, so we
can only show "<unknown>:0:".
Also, allow subsection numbers up to 2147483647, which is the maximum value GNU
assembler supports. (GNU assembler also supports negative numbers.)
Summary: The FixupOffsetInCsect should be 0 for R_REF relocation since it specifies a nonrelocating reference. Otherwise liker would try to relocate the symbol through its address and an error like following occurred.
```
ld: 0711-547 SEVERE ERROR: Object /tmp/1-2a7ea1.o cannot be processed.
RLD address 0x65 for section 2 (.data) is
not contained in the section.
```
Reviewed By: shchenz
Differential Revision: https://reviews.llvm.org/D152777
Detail: Follow up to D144999, where we emitted DWARF for non-canonical personality.
Reviewed By: jyknight
Differential Revision: https://reviews.llvm.org/D152540
