Commit Graph

3880 Commits

Author SHA1 Message Date
Nicholas Wilson e408a89a3a [WebAssembly] Cleanup of the way globals and global flags are handled
Differential Revision: https://reviews.llvm.org/D44030

llvm-svn: 338894
2018-08-03 14:33:37 +00:00
Simon Pilgrim 25b15f1026 Fix "not all control paths return a value" MSVC warning.
llvm-svn: 338529
2018-08-01 13:00:11 +00:00
Jonas Devlieghere 8acb74e01f [MC] Report fatal error for DWARF types for non-ELF object files
Getting the DWARF types section is only implemented for ELF object
files. We already disabled emitting debug types in clang (r337717), but
now we also report an fatal error (rather than crashing) when trying to
obtain this section in MC. Additionally we ignore the generate debug
types flag for unsupported target triples.

See PR38190 for more information.

Differential revision: https://reviews.llvm.org/D50057

llvm-svn: 338527
2018-08-01 12:53:06 +00:00
Hsiangkai Wang 2089e4c8f1 [DebugInfo] Fix build failed in clang-x86_64-linux-selfhost-modules.
Only generate symbol difference expression if needed.

llvm-svn: 338484
2018-08-01 04:17:41 +00:00
Hsiangkai Wang 5c63af0d04 [DebugInfo] Generate fixups as emitting DWARF .debug_line.
It is necessary to generate fixups in .debug_line as relaxation is
enabled due to the address delta may be changed after relaxation.

DWARF will record the mappings of lines and addresses in
.debug_line section. It will encode the information using special
opcodes, standard opcodes and extended opcodes in Line Number
Program. I use DW_LNS_fixed_advance_pc to encode fixed length
address delta and DW_LNE_set_address to encode absolute address
to make it possible to generate fixups in .debug_line section.

Differential Revision: https://reviews.llvm.org/D46850

llvm-svn: 338477
2018-08-01 02:18:06 +00:00
Andrea Di Biagio a1852b6194 [llvm-mca][BtVer2] Teach how to identify dependency-breaking idioms.
This patch teaches llvm-mca how to identify dependency breaking instructions on
btver2.

An example of dependency breaking instructions is the zero-idiom XOR (example:
`XOR %eax, %eax`), which always generates zero regardless of the actual value of
the input register operands.
Dependency breaking instructions don't have to wait on their input register
operands before executing. This is because the computation is not dependent on
the inputs.

Not all dependency breaking idioms are also zero-latency instructions. For
example, `CMPEQ %xmm1, %xmm1` is independent on
the value of XMM1, and it generates a vector of all-ones.
That instruction is not eliminated at register renaming stage, and its opcode is
issued to a pipeline for execution. So, the latency is not zero. 

This patch adds a new method named isDependencyBreaking() to the MCInstrAnalysis
interface. That method takes as input an instruction (i.e. MCInst) and a
MCSubtargetInfo.
The default implementation of isDependencyBreaking() conservatively returns
false for all instructions. Targets may override the default behavior for
specific CPUs, and return a value which better matches the subtarget behavior.

In future, we should teach to Tablegen how to automatically generate the body of
isDependencyBreaking from scheduling predicate definitions. This would allow us
to expose the knowledge about dependency breaking instructions to the machine
schedulers (and, potentially, other codegen passes).

Differential Revision: https://reviews.llvm.org/D49310

llvm-svn: 338372
2018-07-31 13:21:43 +00:00
Fangrui Song f78650a8de Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

llvm-svn: 338293
2018-07-30 19:41:25 +00:00
Martin Storsjo 390bce4322 [MC] Add support for the .rva assembler directive for COFF targets
Even though gas doesn't document it, it has been supported there for
a very long time.

This produces the 32 bit relative virtual address (aka image relative
address) for a given symbol. ".rva foo" is essentially equal to
".long foo@imgrel".

Differential Revision: https://reviews.llvm.org/D49821

llvm-svn: 338063
2018-07-26 20:11:26 +00:00
Michael Kruse 6f1da6e345 [ADT] Replace std::isprint by llvm::isPrint.
The standard library functions ::isprint/std::isprint have platform-
and locale-dependent behavior which makes LLVM's output less
predictable. In particular, regression tests my fail depending on the
implementation of these functions.

Implement llvm::isPrint in StringExtras.h with a standard behavior and
replace all uses of ::isprint/std::isprint by a call it llvm::isPrint.
The function is inlined and does not look up language settings so it
should perform better than the standard library's version.

Such a replacement has already been done for isdigit, isalpha, isxdigit
in r314883. gtest does the same in gtest-printers.cc using the following
justification:

    // Returns true if c is a printable ASCII character.  We test the
    // value of c directly instead of calling isprint(), which is buggy on
    // Windows Mobile.
    inline bool IsPrintableAscii(wchar_t c) {
      return 0x20 <= c && c <= 0x7E;
    }

Similar issues have also been encountered by Julia:
https://github.com/JuliaLang/julia/issues/7416

I noticed the problem myself when on Windows isprint('\t') started to
evaluate to true (see https://stackoverflow.com/questions/51435249) and
thus caused several unit tests to fail. The result of isprint doesn't
seem to be well-defined even for ASCII characters. Therefore I suggest
to replace isprint by a platform-independent version.

Differential Revision: https://reviews.llvm.org/D49680

llvm-svn: 338034
2018-07-26 15:31:41 +00:00
Martin Storsjo 9dafd6f6d9 Revert "[COFF] Use comdat shared constants for MinGW as well"
This reverts commit r337951.

While that kind of shared constant generally works fine in a MinGW
setting, it broke some cases of inline assembly that worked before:

$ cat const-asm.c
int MULH(int a, int b) {
    int rt, dummy;
    __asm__ (
        "imull %3"
        :"=d"(rt), "=a"(dummy)
        :"a"(a), "rm"(b)
    );
    return rt;
}
int func(int a) {
    return MULH(a, 1);
}
$ clang -target x86_64-win32-gnu -c const-asm.c -O2
const-asm.c:4:9: error: invalid variant '00000001'
        "imull %3"
        ^
<inline asm>:1:15: note: instantiated into assembly here
        imull __real@00000001(%rip)
                     ^

A similar error is produced for i686 as well. The same test with a
target of x86_64-win32-msvc or i686-win32-msvc works fine.

llvm-svn: 338018
2018-07-26 10:48:20 +00:00
Martin Storsjo ff33a95ed4 [COFF] Use comdat shared constants for MinGW as well
GNU binutils tools have no problems with this kind of shared constants,
provided that we actually hook it up completely in AsmPrinter and
produce a global symbol.

This effectively reverts SVN r335918 by hooking the rest of it up
properly.

This feature was implemented originally in SVN r213006, with no reason
for why it can't be used for MinGW other than the fact that GCC doesn't
do it while MSVC does.

Differential Revision: https://reviews.llvm.org/D49646

llvm-svn: 337951
2018-07-25 18:35:42 +00:00
Martin Storsjo db42d51ee3 [MC] Add a separate flag for skipping comdat constant sections for MinGW. NFC.
This actually has nothing to do with the associative comdat sections
that aren't supported by GNU binutils ld.

Clarify the comments from SVN r335918 and use a separate flag for it.

Differential Revision: https://reviews.llvm.org/D49645

llvm-svn: 337757
2018-07-23 22:15:25 +00:00
Martin Storsjo 100fc97051 [COFF] Fix assembly output of comdat sections without an attached symbol
Since SVN r335286, the .xdata sections are produced without an attached
symbol, which requires using a different syntax when printing assembly
output.

Instead of the usual syntax of '.section <name>,"dr",discard,<symbol>',
use '.section <name>,"dr"' + '.linkonce discard' (which is what GCC
uses for all assembly output).

This fixes PR38254.

Differential Revision: https://reviews.llvm.org/D49651

llvm-svn: 337756
2018-07-23 22:15:19 +00:00
Nirav Dave e24fcd5382 [MC] Fix nested macro body parsing
Add missing .rep case in nestlevel checking for macro body parsing.

llvm-svn: 337398
2018-07-18 16:17:03 +00:00
Peter Collingbourne 3e22733698 MC: Implement support for new .addrsig and .addrsig_sym directives.
Part of the address-significance tables proposal:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123514.html

Differential Revision: https://reviews.llvm.org/D47744

llvm-svn: 337328
2018-07-17 22:17:18 +00:00
Sam Clegg cf2a9e28b1 [WebAssembly] Remove ELF file support.
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
2018-07-16 23:09:29 +00:00
Wolfgang Pieb fcf3810cf7 [DWARF v5] Generate range list tables into the .debug_rnglists section. No support for split DWARF
and no use of DW_FORM_rnglistx with the DW_AT_ranges attribute.

Reviewer: aprantl

Differential Revision: https://reviews.llvm.org/D49214

llvm-svn: 336927
2018-07-12 18:18:21 +00:00
Jonas Devlieghere 26ddf274d7 Use debug-prefix-map for AT_NAME
AT_NAME was being emitted before the directory paths were remapped. This
ensures that all paths are remapped before anything is emitted.

An additional test case has been added.

Note that this only works if the replacement string is an absolute path.
If not, then AT_decl_file believes the new path is a relative path, and
joins that path with the compilation directory. I do not know of a good
way to resolve this.

Patch by: Siddhartha Bagaria (starsid)

Differential revision: https://reviews.llvm.org/D49169

llvm-svn: 336793
2018-07-11 12:30:35 +00:00
Jonas Devlieghere e13e6dbe40 [MC] Add interface to finish pending labels.
When manually finishing the object writer in dsymutil, it's possible
that there are pending labels that haven't been resolved. This results
in an assertion when the assembler tries to fixup a label that doesn't
have an address yet.

Differential revision: https://reviews.llvm.org/D49131

llvm-svn: 336688
2018-07-10 15:32:17 +00:00
Paul Robinson c17c8bf749 Support -fdebug-prefix-map in llvm-mc. This is useful to omit the
debug compilation dir when compiling assembly files with -g.
Part of PR38050.

Patch by Siddhartha Bagaria!

Differential Revision: https://reviews.llvm.org/D48988

llvm-svn: 336680
2018-07-10 14:41:54 +00:00
Francis Visoiu Mistrih 4d5b1073ba [MC] Error on a .zerofill directive in a non-virtual section
On darwin, all virtual sections have zerofill type, and having a
.zerofill directive in a non-virtual section is not allowed. Instead of
asserting, show a nicer error.

In order to use the equivalent of .zerofill in a non-virtual section,
the usage of .zero of .space is required.

This patch replaces the assert with an error.

Differential Revision: https://reviews.llvm.org/D48517

llvm-svn: 336127
2018-07-02 17:29:43 +00:00
Eric Christopher 53054141a7 Add an entry for rodata constant merge sections to the default
section flags in the ELF assembler. This matches the defaults
given in the rest of MC.

Fixes PR37997 where we couldn't assemble our own assembly output
without warnings.

llvm-svn: 336072
2018-07-02 00:16:39 +00:00
Eric Christopher b7a52bb28a Add a warning if someone attempts to add extra section flags to sections
with well defined semantics like .rodata.

llvm-svn: 335558
2018-06-25 23:53:54 +00:00
Alexander Richardson 85e200e934 Add Triple::isMIPS()/isMIPS32()/isMIPS64(). NFC
There are quite a few if statements that enumerate all these cases. It gets
even worse in our fork of LLVM where we also have a Triple::cheri (which
is mips64 + CHERI instructions) and we had to update all if statements that
check for Triple::mips64 to also handle Triple::cheri. This patch helps to
reduce our diff to upstream and should also make some checks more readable.

Reviewed By: atanasyan

Differential Revision: https://reviews.llvm.org/D48548

llvm-svn: 335493
2018-06-25 16:49:20 +00:00
Paul Robinson 11539b0969 [DWARFv5] Allow ".loc 0" to refer to the root file.
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
2018-06-22 14:16:11 +00:00
George Rimar dcf59c5480 Recommit r335333 "[MC] - Add .stack_size sections into groups and link them with .text"
With compilation fix.

Original commit message:

D39788 added a '.stack-size' section containing metadata on function stack sizes
to output ELF files behind the new -stack-size-section flag.

This change does following two things on top:

1) Imagine the case when there are -ffunction-sections flag given and there are text sections in COMDATs. 
    The patch adds a '.stack-size' section into corresponding COMDAT group, so that linker will be able to
    eliminate them fast during resolving the COMDATs.
2) Patch sets a SHF_LINK_ORDER flag and links '.stack-size' with the corresponding .text.
   With that linker will be able to do -gc-sections on dead stack sizes sections.

Differential revision: https://reviews.llvm.org/D46874

llvm-svn: 335336
2018-06-22 10:53:47 +00:00
George Rimar 6d448da1be Revert r335332 "[MC] - Add .stack_size sections into groups and link them with .text"
It broke bots.

http://lab.llvm.org:8011/builders/clang-ppc64le-linux-lnt/builds/12891
http://lab.llvm.org:8011/builders/clang-cmake-x86_64-sde-avx512-linux/builds/9443
http://lab.llvm.org:8011/builders/lldb-x86_64-ubuntu-14.04-buildserver/builds/25551

llvm-svn: 335333
2018-06-22 10:27:33 +00:00
George Rimar e14485a0c6 [MC] - Add .stack_size sections into groups and link them with .text
D39788 added a '.stack-size' section containing metadata on function stack sizes
to output ELF files behind the new -stack-size-section flag.

This change does following two things on top:

1) Imagine the case when there are -ffunction-sections flag given and there are text sections in COMDATs. 
    The patch adds a '.stack-size' section into corresponding COMDAT group, so that linker will be able to
    eliminate them fast during resolving the COMDATs.
2) Patch sets a SHF_LINK_ORDER flag and links '.stack-size' with the corresponding .text.
   With that linker will be able to do -gc-sections on dead stack sizes sections.

Differential revision: https://reviews.llvm.org/D46874

llvm-svn: 335332
2018-06-22 10:10:53 +00:00
Reid Kleckner 13c9ee684c [mingw] Fix GCC ABI compatibility for comdat things
Summary:
GCC and the binutils COFF linker do comdats differently from MSVC.
If we want to be ABI compatible, we have to do what they do, which is to
emit unique section names like ".text$_Z3foov" instead of short section
names like ".text". Otherwise, the binutils linker gets confused and
reports multiple definition errors when two object files from GCC and
Clang containing the same inline function are linked together.

The best description of the issue is probably at
https://github.com/Alexpux/MINGW-packages/issues/1677, we don't seem to
have a good one in our tracker.

I fixed up the .pdata and .xdata sections needed everywhere other than
32-bit x86. GCC doesn't use associative comdats for those, it appears to
rely on the section name.

Reviewers: smeenai, compnerd, mstorsjo, martell, mati865

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D48402

llvm-svn: 335286
2018-06-21 20:27:38 +00:00
Paul Robinson 547adcaaac [DWARF] Warn on and ignore ".file 0" for DWARF v4 and earlier.
This had been messing with the directory table for prior versions, and
also could induce a crash when generating asm output.

llvm-svn: 335254
2018-06-21 16:42:03 +00:00
Eric Christopher 12e221d9b9 Remove FIXME comment about WIP.
This is the only line other than the function signature remaining
of the original patch.

llvm-svn: 335208
2018-06-21 07:15:19 +00:00
Paul Robinson 8e3e374e5f [DWARF] Don't keep a ref to possibly stack allocated data.
llvm-svn: 335146
2018-06-20 17:08:46 +00:00
Paul Robinson 37fbb92652 Remove a redundant initialization. NFC
llvm-svn: 335143
2018-06-20 16:12:03 +00:00
Andrea Di Biagio 2145b13fc9 [llvm-mca][X86] Teach how to identify register writes that implicitly clear the upper portion of a super-register.
This patch teaches llvm-mca how to identify register writes that implicitly zero
the upper portion of a super-register.

On X86-64, a general purpose register is implemented in hardware as a 64-bit
register. Quoting the Intel 64 Software Developer's Manual: "an update to the
lower 32 bits of a 64 bit integer register is architecturally defined to zero
extend the upper 32 bits".  Also, a write to an XMM register performed by an AVX
instruction implicitly zeroes the upper 128 bits of the aliasing YMM register.

This patch adds a new method named clearsSuperRegisters to the MCInstrAnalysis
interface to help identify instructions that implicitly clear the upper portion
of a super-register.  The rest of the patch teaches llvm-mca how to use that new
method to obtain the information, and update the register dependencies
accordingly.

I compared the kernels from tests clear-super-register-1.s and
clear-super-register-2.s against the output from perf on btver2.  Previously
there was a large discrepancy between the estimated IPC and the measured IPC.
Now the differences are mostly in the noise.

Differential Revision: https://reviews.llvm.org/D48225

llvm-svn: 335113
2018-06-20 10:08:11 +00:00
Nirav Dave b35f9e1459 Fix typoed cast to avoid assertion in MCFragment::dump.
llvm-svn: 334959
2018-06-18 16:26:11 +00:00
Sean Fertile cac28aeb3f [PowerPC] Add support for high and higha symbol modifiers on tls modifers.
Enables using the high and high-adjusted symbol modifiers on thread local
storage modifers in powerpc assembly. Needed to be able to support 64 bit
thread-pointer and dynamic-thread-pointer access sequences.

Differential Revision: https://reviews.llvm.org/D47754

llvm-svn: 334856
2018-06-15 19:47:16 +00:00
Sean Fertile 80b8f82f17 [PPC64] Support "symbol@high" and "symbol@higha" symbol modifers.
Add support for the "@high" and "@higha" symbol modifiers in powerpc64 assembly.
The modifiers represent accessing the segment consiting of bits 16-31 of a
64-bit address/offset.

Differential Revision: https://reviews.llvm.org/D47729

llvm-svn: 334855
2018-06-15 19:47:11 +00:00
Peter Smith 1503fc0fd0 [MC] Move bundling and MCSubtargetInfo to MCEncodedFragment [NFC]
Instruction bundling is only supported on descendants of the
MCEncodedFragment type. By moving the bundling functionality and
MCSubtargetInfo to this class it makes it easier to set and extract the
MCSubtargetInfo when it is necessary.

This is a refactoring change that will make it easier to pass the
MCSubtargetInfo through to writeNops when nop padding is required.

Differential Revision: https://reviews.llvm.org/D45959

llvm-svn: 334814
2018-06-15 09:48:18 +00:00
Sam Clegg c0dba0af01 Revert "[MC] Factor MCObjectStreamer::addFragmentAtoms out of MachO streamer."
This reverts rL331412.  We didn't up using fragment atoms
in the wasm object writer after all.

Differential Revision: https://reviews.llvm.org/D48173

llvm-svn: 334734
2018-06-14 17:11:19 +00:00
Sam Clegg 8c32e913b5 [MC] Move MCAssembler::dump into the correct cpp file. NFC
Differential Revision: https://reviews.llvm.org/D46556

llvm-svn: 334713
2018-06-14 14:04:23 +00:00
Paul Robinson cc7344aae3 [DWARFv5] Tolerate files not all having an MD5 checksum.
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
2018-06-14 13:38:20 +00:00
Paul Robinson f69316c617 [DWARFv5] llvm-mc -dwarf-version does not imply -g.
Don't provide the assembler source as the "root file" unless the user
asked to have debug info for the assembler source (with -g).

If the source doesn't provide an explicit ".file 0" then (a) use the
compilation directory as directory #0, and (b) use the file #1 info
for file #0 also.

Differential Revision: https://reviews.llvm.org/D48055

llvm-svn: 334512
2018-06-12 16:09:03 +00:00
Konstantin Zhuravlyov 3e5d66ac66 AMDGPU: Add 64-bit relative variant kind
Differential Revision: https://reviews.llvm.org/D47601

llvm-svn: 334443
2018-06-11 21:37:57 +00:00
Peter Smith 57f661bd7d [MC] Pass MCSubtargetInfo to fixupNeedsRelaxation and applyFixup
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
2018-06-06 09:40:06 +00:00
Sanjay Patel 59313be8d3 [CodeGen] assume max/default throughput for unspecified instructions
This is a fix for the problem arising in D47374 (PR37678):
https://bugs.llvm.org/show_bug.cgi?id=37678

We may not have throughput info because it's not specified in the model 
or it's not available with variant scheduling, so assume that those
instructions can execute/complete at max-issue-width.

Differential Revision: https://reviews.llvm.org/D47723

llvm-svn: 334055
2018-06-05 23:34:45 +00:00
Nirav Dave 05b589101e [MC][X86] Allow assembler variable assignment to register name.
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
2018-06-05 15:13:39 +00:00
Michael J. Spencer ae6eeaea92 [MC] Add assembler support for .cg_profile.
Object FIle Representation
At codegen time this is emitted into the ELF file a pair of symbol indices and a weight. In assembly it looks like:

.cg_profile a, b, 32
.cg_profile freq, a, 11
.cg_profile freq, b, 20

When writing an ELF file these are put into a SHT_LLVM_CALL_GRAPH_PROFILE (0x6fff4c02) section as (uint32_t, uint32_t, uint64_t) tuples as (from symbol index, to symbol index, weight).

Differential Revision: https://reviews.llvm.org/D44965

llvm-svn: 333823
2018-06-02 16:33:01 +00:00
Andrea Di Biagio be8616f5f2 [MCSchedule] Add the ability to compute the latency and throughput information for MCInst.
This patch extends the MCSchedModel API with new methods that can be used to
obtain the latency and reciprocal througput information for an MCInst.

Scheduling models have recently gained the ability to resolve variant scheduling
classes associated with MCInst objects. Before, models were only able to resolve
a variant scheduling class from a MachineInstr object.

This patch is mainly required by D47374 to avoid regressing a pair of x86
specific -print-schedule tests for btver2. Patch D47374 introduces a new variant
class to teach the btver scheduling model (x86 target) how to correctly compute
the latency profile for some zero-idioms using the new scheduling predicates.

The new methods added by this patch would be mainly used by llc when flag
-print-schedule is specified. In particular, tests that contain inline assembly
require that code is parsed at code emission stage into a sequence of MCInst.
That forces the print-schedule functionality to query the latency/rthroughput
information for MCInst instructions too. If we don't expose this new API, then
we lose "-print-schedule" test coverage as soon as variant scheduling classes
are added to the x86 models.

The tablegen SubtargetEmitter changes teaches how to query latency profile
information using a object that derives from TargetSubtargetInfo. Note that this
should really have been part of r333286. To avoid code duplication, the logic
that "resolves" variant scheduling classes for MCInst, has been moved to a
common place in MC. That logic is used by the "resolveVariantSchedClass" methods
redefined in override by the tablegen'd GenSubtargetInfo classes.

Differential Revision: https://reviews.llvm.org/D47536

llvm-svn: 333650
2018-05-31 13:30:42 +00:00
Sam Clegg 105bdc2557 [WebAssembly] MC: Add compile-twice test and fix corresponding bug
Differential Revision: https://reviews.llvm.org/D47398

llvm-svn: 333494
2018-05-30 02:57:20 +00:00
Alex Bradbury 257d5b5639 [RISCV] Add symbol diff relocation support for RISC-V
For RISC-V it is desirable to have relaxation happen in the linker once 
addresses are known, and as such the size between two instructions/byte 
sequences in a section could change.

For most assembler expressions, this is fine, as the absolute address results 
in the expression being converted to a fixup, and finally relocations. 
However, for expressions such as .quad .L2-.L1, the assembler folds this down 
to a constant once fragments are laid out, under the assumption that the 
difference can no longer change, although in the case of linker relaxation the 
differences can change at link time, so the constant is incorrect. One place 
where this commonly appears is in debug information, where the size of a 
function expression is in a form similar to the above.

This patch extends the assembler to allow an AsmBackend to declare that it 
does not want the assembler to fold down this expression, and instead generate 
a pair of relocations that allow the linker to carry out the calculation. In 
this case, the expression is not folded, but when it comes to emitting a 
fixup, the generic FK_Data_* fixups are converted into a pair, one for the 
addition half, one for the subtraction, and this is passed to the relocation 
generating methods as usual. I have named these FK_Data_Add_* and 
FK_Data_Sub_* to indicate which half these are for.

For RISC-V, which supports this via e.g. the R_RISCV_ADD64, R_RISCV_SUB64 pair 
of relocations, these are also set to always emit relocations relative to 
local symbols rather than section offsets. This is to deal with the fact that 
if relocations were calculated on e.g. .text+8 and .text+4, the result 12 
would be stored rather than 4 as both addends are added in the linker.

Differential Revision: https://reviews.llvm.org/D45181
Patch by Simon Cook.

llvm-svn: 333079
2018-05-23 12:36:18 +00:00
Peter Collingbourne 2d3eaeb2d4 MC: Remove dead code. NFCI.
This code appears to have been copied from the mach-o streamer. It has
no effect in ELF because indirect symbols are specific to mach-o.

llvm-svn: 332926
2018-05-22 01:20:46 +00:00
Peter Collingbourne 63062d9d0f MC: Introduce an ELF dwo object writer and teach llvm-mc about it.
Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47051

llvm-svn: 332875
2018-05-21 19:44:54 +00:00
Peter Collingbourne f0226e62a8 MC: Extract a derived class from ELFObjectWriter. NFCI.
This class will be used to create regular, non-split ELF files.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47049

llvm-svn: 332870
2018-05-21 19:30:59 +00:00
Peter Collingbourne dcd7d6c331 MC: Separate creating a generic object writer from creating a target object writer. NFCI.
With this we gain a little flexibility in how the generic object
writer is created.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47045

llvm-svn: 332868
2018-05-21 19:20:29 +00:00
Peter Collingbourne a29fe579f4 MC: Extract ELFObjectWriter's ELF writing functionality into an ELFWriter class. NFCI.
The idea is that we will be able to use this class to create multiple
files.

Differential Revision: https://reviews.llvm.org/D47048

llvm-svn: 332867
2018-05-21 19:18:28 +00:00
Peter Collingbourne 59a6fc469f MC: Remove stream and output functions from MCObjectWriter. NFCI.
Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47043

llvm-svn: 332864
2018-05-21 18:28:57 +00:00
Peter Collingbourne 438390fae1 MC: Have the object writers return the number of bytes written. NFCI.
This removes the last external use of the stream.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47042

llvm-svn: 332863
2018-05-21 18:23:50 +00:00
Peter Collingbourne f17b149d8c MC: Change object writers to use endian::Writer. NFCI.
Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47040

llvm-svn: 332861
2018-05-21 18:17:42 +00:00
Peter Collingbourne 147db3e628 MC: Change MCAssembler::writeSectionData and writeFragmentPadding to take a raw_ostream. NFCI.
Also clean up a couple of hacks where we were writing the section
contents to another stream by setting the object writer's stream,
writing and setting it back.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47038

llvm-svn: 332858
2018-05-21 18:11:35 +00:00
Peter Collingbourne 571a3301ae MC: Change MCAsmBackend::writeNopData() to take a raw_ostream instead of an MCObjectWriter. NFCI.
To make this work I needed to add an endianness field to MCAsmBackend
so that writeNopData() implementations know which endianness to use.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47035

llvm-svn: 332857
2018-05-21 17:57:19 +00:00
Peter Collingbourne e3f652973e Support: Simplify endian stream interface. NFCI.
Provide some free functions to reduce verbosity of endian-writing
a single value, and replace the endianness template parameter with
a field.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47032

llvm-svn: 332757
2018-05-18 19:46:24 +00:00
Peter Collingbourne f7b81db715 MC: Change the streamer ctors to take an object writer instead of a stream. NFCI.
The idea is that a client that wants split dwarf would create a
specific kind of object writer that creates two files, and use it to
create the streamer.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47050

llvm-svn: 332749
2018-05-18 18:26:45 +00:00
Nirav Dave 588fad4d3b [MC] Relax .fill size requirements
Avoid requirement that number of values must be known at assembler
time.

Fixes PR33586.

Reviewers: rnk, peter.smith, echristo, jyknight

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D46703

llvm-svn: 332741
2018-05-18 17:45:48 +00:00
Shiva Chen 6e07dfb148 [RISCV] Add WasForced parameter to MCAsmBackend::fixupNeedsRelaxationAdvanced
For RISCV branch instructions, we need to preserve relocation types when linker
relaxation enabled, so then linker could modify offset when the branch offsets
changed.

We preserve relocation types by define shouldForceRelocation.
IsResolved return by evaluateFixup will always false when shouldForceRelocation
return true. It will make RISCV MC Branch Relaxation always relax 16-bit
branches to 32-bit form, even if the symbol actually could be resolved.

To avoid 16-bit branches always relax to 32-bit form when linker relaxation
enabled, we add a new parameter WasForced to indicate that the symbol actually
couldn't be resolved and not forced by shouldForceRelocation return true.

RISCVAsmBackend::fixupNeedsRelaxationAdvanced could relax branches with
unresolved symbols by (!IsResolved && !WasForced).

RISCV MC Branch Relaxation is needed because RISCV could perform 32-bit
to 16-bit transformation in MC layer.

Differential Revision: https://reviews.llvm.org/D46350

llvm-svn: 332696
2018-05-18 06:42:21 +00:00
Sam Clegg c0d41195b5 [WebAssembly] MC: Fix typo in comment
llvm-svn: 332632
2018-05-17 17:15:15 +00:00
Sam Clegg 6a32560886 [WebAssembly] Remove unused headers in MCWasmObjectWriter
Differential Revision: https://reviews.llvm.org/D46969

llvm-svn: 332535
2018-05-16 22:13:18 +00:00
Sam Clegg 6ccb59b3e9 [WebAssembly] MC: Ensure that FUNCTION_OFFSET relocations are always against function symbols.
The getAtom() method wasn't doing what we needed in all cases. We want
the symbols for the function which defines that section. We can compute
this easily enough and we know that we have at most one function in each
section.

Once this lands I will revert rL331412 which is no longer needed.

Fixes PR37409

Differential Revision: https://reviews.llvm.org/D46970

llvm-svn: 332517
2018-05-16 20:09:05 +00:00
Sam Clegg 5f87ab336e [WebAssembly] Move toString helpers to BinaryFormat
Subscribers: dschuff, mgorny, jgravelle-google, aheejin, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D46847

llvm-svn: 332305
2018-05-14 22:42:07 +00:00
Nicola Zaghen d34e60ca85 Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624

llvm-svn: 332240
2018-05-14 12:53:11 +00:00
Bill Wendling 2a302210d0 Correct compatibility with the GNU Assembler's handling of comparison ops
GAS returns -1 for a comparison operator if the result is true and 0 if false.

  https://www.sourceware.org/binutils/docs-2.12/as.info/Infix-Ops.html#Infix%20Ops

llvm-svn: 332215
2018-05-14 05:25:36 +00:00
Sam Clegg b210c64b28 [WebAssembly] Create section start symbols automatically for all sections
These symbols only get included in the output symbols table if
they are used in a relocation.

This behaviour matches more closely the ELF object writer.

Differential Revision: https://reviews.llvm.org/D46561

llvm-svn: 332005
2018-05-10 17:38:35 +00:00
Peter Collingbourne 8e173e1189 MC: Remove dead code. NFCI.
We should never emit an SHT_DYNSYM into an object file.

llvm-svn: 331821
2018-05-08 22:59:05 +00:00
Sam Clegg 25d8e68b87 [WebAssembly] MC: Use existing MCSymbol.Index field rather than inventing extra mapping
MCSymbol has getIndex/setIndex which are implementation defined
and on other platforms are used to store the symbol table
index.  It makes sense to use this rather than invent a new
mapping.

Differential Revision: https://reviews.llvm.org/D46555

llvm-svn: 331705
2018-05-08 00:08:21 +00:00
Sam Clegg 22c568ba73 [MC] ELFObjectWriter: Removing unneeded variable and cast
Differential Revision: https://reviews.llvm.org/D46289

llvm-svn: 331704
2018-05-07 23:52:17 +00:00
Sam Clegg fb807d4dd4 [WebAssembly] Ensure all .debug_XXX section has proper symbol names
Updated wasm section symbols names to match section name, and ensure all
referenced sections will have a symbol (per DWARF spec v3, Figure 43)

Patch by Yury Delendik!

Differential Revision: https://reviews.llvm.org/D46543

llvm-svn: 331664
2018-05-07 19:40:50 +00:00
Sam Clegg 4d57fbd02a [WebAssembly] MC: Create and use first class section symbols
Differential Revision: https://reviews.llvm.org/D46335

llvm-svn: 331413
2018-05-02 23:11:38 +00:00
Sam Clegg 87cc4dbde7 [MC] Factor MCObjectStreamer::addFragmentAtoms out of MachO streamer.
This code previously existed only in MCMachOStreamer but is
useful for WebAssembly too.  See: D46335

Differential Revision: https://reviews.llvm.org/D46297

llvm-svn: 331412
2018-05-02 23:01:10 +00:00
Sam Clegg d1f0910a54 Fix release build breakage
This function was added in rL331220 but wasn't
testing in release configurations.

llvm-svn: 331320
2018-05-02 00:10:28 +00:00
Adrian Prantl 5f8f34e459 Remove \brief commands from doxygen comments.
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
2018-05-01 15:54:18 +00:00
Florian Hahn ba4d85ee3f [MC] Add llvm_unreachable to toString to fix compile time warning.
Without this change, GCC 7 raises the warning below:
        control reaches end of non-void function

Reviewers: sbc100, andreadb

Reviewed By: andreadb

Differential Revision: https://reviews.llvm.org/D46304

llvm-svn: 331255
2018-05-01 11:18:31 +00:00
Gabor Buella 0537fdbcab NFC, Avoid a warning in WasmObjectWriter
The warning was (introduced in r331220):

lib/MC/WasmObjectWriter.cpp:51:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

llvm-svn: 331251
2018-05-01 10:21:10 +00:00
Sam Clegg a165f2d60d [WebAssembly] MC: Improve debug output
llvm-svn: 331220
2018-04-30 19:40:57 +00:00
Nirav Dave 6c0665e221 [MC] Change AsmParser to leverage Assembler during evaluation
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
2018-04-30 19:22:40 +00:00
Nico Weber 432a38838d IWYU for llvm-config.h in llvm, additions.
See r331124 for how I made a list of files missing the include.
I then ran this Python script:

    for f in open('filelist.txt'):
        f = f.strip()
        fl = open(f).readlines()

        found = False
        for i in xrange(len(fl)):
            p = '#include "llvm/'
            if not fl[i].startswith(p):
                continue
            if fl[i][len(p):] > 'Config':
                fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
                found = True
                break
        if not found:
            print 'not found', f
        else:
            open(f, 'w').write(''.join(fl))

and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.

No intended behavior change.

llvm-svn: 331184
2018-04-30 14:59:11 +00:00
Vlad Tsyrklevich 201a1086cf ELFObjectWriter: Allow one unique symver per symbol
Summary:
Only allow a single unique .symver alias per symbol. This matches the
behavior of gas. I noticed that we ignored multiple mismatched symver
directives looking at https://reviews.llvm.org/D45798

Reviewers: pcc, tejohnson, espindola

Reviewed By: pcc

Subscribers: emaste, arichardson, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D45845

llvm-svn: 331078
2018-04-27 20:32:34 +00:00
Nirav Dave 6b01b88012 [MC] Undo spurious commit added into r331052.
llvm-svn: 331055
2018-04-27 16:16:06 +00:00
Nirav Dave 38b4b54a2c [MC] Provide default value for IsResolved.
llvm-svn: 331052
2018-04-27 16:11:24 +00:00
Nirav Dave 1b5533c9e8 [MC] Modify MCAsmStreamer to always build MCAssembler. NFCI.
llvm-svn: 331048
2018-04-27 15:45:54 +00:00
Nirav Dave 8728e097df [MC] Allow MCAssembler to be constructed without all subcomponents. NFCI.
llvm-svn: 331047
2018-04-27 15:45:27 +00:00
Sam Clegg d5504a0a62 [WebAssembly] Section symbols must have local binding
Summary: Also test for symbols information in test/MC/WebAssembly/debug-info.ll.

Subscribers: jfb, dschuff, jgravelle-google, aheejin, sunfish, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D46160

llvm-svn: 331005
2018-04-27 00:17:21 +00:00
Sam Clegg 6a31a0d694 [WebAssembly] Write DWARF data into wasm object file
- Writes ".debug_XXX" into corresponding custom sections.
- Writes relocation records into "reloc.debug_XXX" sections.

Patch by Yury Delendik!

Differential Revision: https://reviews.llvm.org/D44184

llvm-svn: 330982
2018-04-26 19:27:28 +00:00
Sam Clegg 6bb5a41f99 [WebAssembly] Add version to object file metadata
Summary: See https://github.com/WebAssembly/tool-conventions/issues/54

Subscribers: jfb, dschuff, jgravelle-google, aheejin, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D46069

llvm-svn: 330969
2018-04-26 18:15:32 +00:00
Reid Kleckner 2c6430fe3c [codeview] Ignore .cv_loc directives at the end of a function
If no data or instructions are emitted after a location directive, we
should clear the cv_loc when we change sections, or it will be emitted
at the beginning of the next section. This violates our invariant that
all .cv_loc directives belong to the same section. Add clearer
assertions for this.

llvm-svn: 330884
2018-04-25 23:34:15 +00:00
Chandler Carruth 7e1c3345a0 [wasm] Fix uninitialized memory introduced in r330749.
Found with MSan. This was causing all the WASM MC tests to fail about
10% of the time.

llvm-svn: 330764
2018-04-24 20:30:56 +00:00
Sam Clegg 6f08c84ae5 [WebAssembly] Use section index in relocation section header
Rather than referring to sections my their code, use the
absolute index of the target section within the module.

See https://github.com/WebAssembly/tool-conventions/issues/52

Differential Revision: https://reviews.llvm.org/D45980

llvm-svn: 330749
2018-04-24 18:11:36 +00:00
Eric Christopher 24004d65a5 Reflow formatting after previous NFC commit.
llvm-svn: 330676
2018-04-24 01:57:03 +00:00
Eric Christopher 29ff50454c Change if-conditionals to else-if as they should all be mutually exclusive.
No functional change intended.

llvm-svn: 330675
2018-04-24 01:57:02 +00:00
Sam Clegg 2322a93709 [WebAssembly] MC: Refactor section creation code
Remove the use of default argument in favor of a separate
startCustomSection method.

Differential Revision: https://reviews.llvm.org/D45794

llvm-svn: 330632
2018-04-23 19:16:19 +00:00
Sam Clegg f009da2448 [WebAssembly] Enabled -triple=wasm32-unknown-unknown-wasm path using ELF directive parser.
This is a temporary solution until a proper WASM implementation of
MCAsmParserExtension is in place, but at least for now will unblock this
path.

Added test to make sure this path works with the WASM Assembler.

Patch By Wouter van Oortmerssen!

Differential Revision: https://reviews.llvm.org/D45386

llvm-svn: 330370
2018-04-19 22:00:53 +00:00
Andrea Di Biagio b9acf13907 [MC] Moved all the remaining logic that computed instruction latency and reciprocal throughput from TargetSchedModel to MCSchedModel.
TargetSchedModel now always delegates to MCSchedModel the computation of
instruction latency and reciprocal throughput.
No functional change intended.

llvm-svn: 330099
2018-04-15 17:32:17 +00:00