Commit Graph

391 Commits

Author SHA1 Message Date
Reid Kleckner a9f4cc9510 [codeview] Add new directives to record inlined call site line info
Summary:
Previously we were trying to represent this with the "contains" list of
the .cv_inline_linetable directive, which was not enough information.
Now we directly represent the chain of inlined call sites, so we know
what location to emit when we encounter a .cv_loc directive of an inner
inlined call site while emitting the line table of an outer function or
inlined call site. Fixes PR29146.

Also fixes PR29147, where we would crash when .cv_loc directives crossed
sections. Now we write down the section of the first .cv_loc directive,
and emit an error if any other .cv_loc directive for that function is in
a different section.

Also fixes issues with discontiguous inlined source locations, like in
this example:

  volatile int unlikely_cond = 0;
  extern void __declspec(noreturn) abort();
  __forceinline void f() {
    if (!unlikely_cond) abort();
  }
  int main() {
    unlikely_cond = 0;
    f();
    unlikely_cond = 0;
  }

Previously our tables gave bad location information for the 'abort'
call, and the debugger wouldn't snow the inlined stack frame for 'f'.
It is important to emit good line tables for this code pattern, because
it comes up whenever an asan bug occurs in an inlined function. The
__asan_report* stubs are generally placed after the normal function
epilogue, leading to discontiguous regions of inlined code.

Reviewers: majnemer, amccarth

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D24014

llvm-svn: 280822
2016-09-07 16:15:31 +00:00
Reid Kleckner a5b1eef846 [MC] Move .cv_loc management logic out of MCContext
MCContext already has many tasks, and separating CodeView out from it is
probably a good idea. The .cv_loc tracking was modelled on the DWARF
tracking which lived directly in MCContext.

Removes the inclusion of MCCodeView.h from MCContext.h, so now there are
only 10 build actions while I hack on CodeView support instead of 265.

llvm-svn: 279847
2016-08-26 17:58:37 +00:00
Simon Atanasyan eb9ed61021 [mips][ias] Support .dtprel[d]word and .tprel[d]word directives
Assembler directives .dtprelword, .dtpreldword, .tprelword, and
.tpreldword generates relocations R_MIPS_TLS_DTPREL32, R_MIPS_TLS_DTPREL64,
R_MIPS_TLS_TPREL32, and R_MIPS_TLS_TPREL64 respectively.

The main motivation for this patch is to be able to write test cases
for checking correctness of the LLD linker's behaviour.

Differential Revision: https://reviews.llvm.org/D23669

llvm-svn: 279439
2016-08-22 16:18:42 +00:00
Nirav Dave 8b3dc876ea [MC] When emitting output hash comments always use standard line comment seperator
llvm-svn: 277146
2016-07-29 14:42:00 +00:00
Nirav Dave a645433c5f [MC] Cleanup Error Handling in AsmParser
Add parseToken and compatriot functions to stitch error checks in
straight linear code. As part of this fix some erronous handling of
directives where the EndOfStatement token either was not checked or
Lexed on termination.

Reviewers: rnk, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D22312

llvm-svn: 275795
2016-07-18 15:24:03 +00:00
Nirav Dave 53a72f4d3c Provide support for preserving assembly comments
Preserve assembly comments from input in output assembly and flags to
toggle property. This is on by default for inline assembly and off in
llvm-mc.

Parsed comments are emitted immediately before an EOL which generally
places them on the expected line.

Reviewers: rtrieu, dwmw2, rnk, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D20020

llvm-svn: 275058
2016-07-11 12:42:14 +00:00
Benjamin Kramer 7b4658ff87 Apply clang-tidy's modernize-loop-convert to lib/MC.
Only minor manual fixes. No functionality change intended.

llvm-svn: 273814
2016-06-26 14:49:00 +00:00
Petr Hosek 17f7a24807 [MC] Check the upper bound in truncate assertion
The truncateToSize function already has assertion to check the
lower boundary for the number bytes, but it does not check the
upper boundary which could still lead to usage errors.

Differential Revision: http://reviews.llvm.org/D20755

llvm-svn: 271773
2016-06-04 04:02:18 +00:00
Petr Hosek faef3207de [MC] Rename EmitFill to emitFill
This is to match the overloaded variants as well as the new style.

Differential Revision: http://reviews.llvm.org/D20690

llvm-svn: 271359
2016-06-01 01:59:58 +00:00
Reid Kleckner fbdbe9e22b [codeview] Improve readability of type record assembly
Adds the method MCStreamer::EmitBinaryData, which is usually an alias
for EmitBytes. In the MCAsmStreamer case, it is overridden to emit hex
dump output like this:
        .byte   0x0e, 0x00, 0x08, 0x10
        .byte   0x03, 0x00, 0x00, 0x00
        .byte   0x00, 0x00, 0x00, 0x00
        .byte   0x00, 0x10, 0x00, 0x00

Also, when verbose asm comments are enabled, this patch prints the dump
output for each comment before its record, like this:
        # ArgList (0x1000) {
        #   TypeLeafKind: LF_ARGLIST (0x1201)
        #   NumArgs: 0
        #   Arguments [
        #   ]
        # }
        .byte   0x06, 0x00, 0x01, 0x12
        .byte   0x00, 0x00, 0x00, 0x00

This should make debugging easier and testing more convenient.

Reviewers: aaboud

Subscribers: majnemer, zturner, amccarth, aaboud, llvm-commits

Differential Revision: http://reviews.llvm.org/D20711

llvm-svn: 271313
2016-05-31 18:45:36 +00:00
Petr Hosek 67a94a795d [MC] Support symbolic expressions in assembly directives
This matches the behavior of GNU assembler which supports symbolic
expressions in absolute expressions used in assembly directives.

Differential Revision: http://reviews.llvm.org/D20752

llvm-svn: 271102
2016-05-28 05:57:48 +00:00
Petr Hosek 97859ccd51 Revert "[MC] Support symbolic expressions in assembly directives"
This reverts commit r271028, it causes the directive_fill.s to fail.

llvm-svn: 271038
2016-05-27 19:58:05 +00:00
Petr Hosek ec73d8b383 [MC] Support symbolic expressions in assembly directives
This matches the behavior of GNU assembler which supports symbolic
expressions in absolute expressions used in assembly directives.

Differential Revision: http://reviews.llvm.org/D20656

llvm-svn: 271028
2016-05-27 18:49:44 +00:00
Reid Kleckner 63d3d6df7d Revert "[MC] Support symbolic expressions in assembly directives"
This reverts commit r270786, it causes the directive_fill.s to fail.

llvm-svn: 270795
2016-05-25 23:29:08 +00:00
Petr Hosek e25837528b [MC] Support symbolic expressions in assembly directives
This matches the behavior of GNU assembler which supports symbolic
expressions in absolute expressions used in assembly directives.

Differential Revision: http://reviews.llvm.org/D20337

llvm-svn: 270786
2016-05-25 22:47:51 +00:00
Reid Kleckner 97837b7b09 [MC] Create unique .pdata sections for every .text section
Summary:
This adds a unique ID to the COFF section uniquing map, similar to the
one we have for ELF.  The unique id is not currently exposed via the
assembler because we don't have a use case for it yet. Users generally
create .pdata with the .seh_* family of directives, and the assembler
internally needs to produce .pdata and .xdata sections corresponding to
the code section.

The association between .text sections and the assembler-created .xdata
and .pdata sections is maintained as an ID field of MCSectionCOFF. The
CFI-related sections are created with the given unique ID, so if more
code is added to the same text section, we can find and reuse the CFI
sections that were already created.

Reviewers: majnemer, rafael

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D19376

llvm-svn: 268331
2016-05-02 23:22:18 +00:00
Mehdi Amini b550cb1750 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
Lang Hames 1b640e05ba [MachO] Add MachO alt-entry directive support.
This patch adds support for the MachO .alt_entry assembly directive, and uses
it for global aliases with non-zero GEP offsets. The alt_entry flag indicates
that a symbol should be layed out immediately after the preceding symbol.
Conceptually it introduces an alternate entry point for a function or data
structure. E.g.:

safe_foo:
  // check preconditions for foo
.alt_entry fast_foo
fast_foo:
  // body of foo, can assume preconditions.

The .alt_entry flag is also implicitly set on assembly aliases of the form:

a = b + C

where C is a non-zero constant, since these have the same effect as an
alt_entry symbol: they introduce a label that cannot be moved relative to the
preceding one. Setting the alt_entry flag on aliases of this form fixes
http://llvm.org/PR25381.

llvm-svn: 263521
2016-03-15 01:43:05 +00:00
David Majnemer 408b5e6603 [MC] Add support for encoding CodeView variable definition ranges
CodeView, like most other debug formats, represents the live range of a
variable so that debuggers might print them out.

They use a variety of records to represent how a particular variable
might be available (in a register, in a frame pointer, etc.) along with
a set of ranges where this debug information is relevant.

However, the format only allows us to use ranges which are limited to a
maximum of 0xF000 in size.  This means that we need to split our debug
information into chunks of 0xF000.

Because the layout of code is not known until *very* late, we must use a
new fragment to record the information we need until we can know
*exactly* what the range is.

llvm-svn: 259868
2016-02-05 01:55:49 +00:00
David Majnemer c9911f28e5 [codeview] Correctly handle inlining functions post-dominated by unreachable
CodeView requires us to accurately describe the extent of the inlined
code.  We did this by grabbing the next debug location in source order
and using *that* to denote where we stopped inlining.  However, this is
not sufficient or correct in instances where there is no next debug
location or the next debug location belongs to the start of another
function.

To get this correct, use the end symbol of the function to denote the
last possible place the inlining could have stopped at.

llvm-svn: 259548
2016-02-02 19:22:34 +00:00
Reid Kleckner 1fcd610c94 [codeview] Wire up the .cv_inline_linetable directive
This directive emits the binary annotations that describe line and code
deltas in inlined call sites. Single-stepping through inlined frames in
windbg now works.

llvm-svn: 259535
2016-02-02 17:41:18 +00:00
Rafael Espindola 52570ea2a2 Fix infinite recursion in MCAsmStreamer::EmitValueImpl.
If a target can only emit 8-bits data, we would loop in EmitValueImpl
since it will try to split a 32-bits data in 1 chunk of 32-bits.

No test since all current targets can emit 32bits at a time.

Patch by Alexandru Guduleasa!

llvm-svn: 259399
2016-02-01 20:36:49 +00:00
David Majnemer 6fcbd7e909 [CodeView] Implement .cv_inline_linetable
This support is _very_ rudimentary, just enough to get some basic data
into the CodeView debug section.

Left to do is:
- Use the combined opcodes to save space.
- Do something about code offsets.

llvm-svn: 259230
2016-01-29 19:24:12 +00:00
Reid Kleckner 2214ed8937 Reland "[CodeView] Use assembler directives for line tables"
This reverts commit r259126 and relands r259117.

This time with updated library dependencies.

llvm-svn: 259130
2016-01-29 00:49:42 +00:00
Reid Kleckner 00d9639c24 Revert "[CodeView] Use assembler directives for line tables"
This reverts commit r259117.

The LineInfo constructor is defined in the codeview library and we have
to link against it now. Doing that isn't trivial, so reverting for now.

llvm-svn: 259126
2016-01-29 00:13:28 +00:00
Reid Kleckner c62e379d22 [CodeView] Use assembler directives for line tables
Adds a new family of .cv_* directives to LLVM's variant of GAS syntax:

- .cv_file: Similar to DWARF .file directives

- .cv_loc: Similar to the DWARF .loc directive, but starts with a
  function id. CodeView line tables are emitted by function instead of
  by compilation unit, so we needed an extra field to communicate this.
  Rather than overloading the .loc direction further, we decided it was
  better to have our own directive.

- .cv_stringtable: Emits the codeview string table at the current
  position. Currently this just contains the filenames as
  null-terminated strings.

- .cv_filechecksums: Emits the file checksum table for all files used
  with .cv_file so far. There is currently no support for emitting
  actual checksums, just filenames.

This moves the line table emission code down into the assembler.  This
is in preparation for implementing the inlined call site line table
format. The inline line table format encoding algorithm requires knowing
the absolute code offsets, so it must run after the assembler has laid
out the code.

David Majnemer collaborated on this patch.

llvm-svn: 259117
2016-01-28 23:31:52 +00:00
Dan Gohman 61d15ae4f5 [MC] Use .p2align instead of .align
For historic reasons, the behavior of .align differs between targets.
Fortunately, there are alternatives, .p2align and .balign, which make the
interpretation of the parameter explicit, and which behave consistently across
targets.

This patch teaches MC to use .p2align instead of .align, so that people reading
code for multiple architectures don't have to remember which way each platform
does its .align directive.

Differential Revision: http://reviews.llvm.org/D16549

llvm-svn: 258750
2016-01-26 00:03:25 +00:00
Daniel Sanders 9f6ad49740 Implement .reloc (constant offset only) with support for R_MIPS_NONE and R_MIPS_32.
Summary:
Support for R_MIPS_NONE allows us to parse MIPS16's usage of .reloc.
R_MIPS_32 was included to be able to better test the directive.

Targets can add their relocations by overriding MCAsmBackend::getFixupKind().

Subscribers: grosbach, rafael, majnemer, dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D13659

llvm-svn: 252888
2015-11-12 13:33:00 +00:00
Rafael Espindola 7ae65d87cf Simplify now that emitValueToOffset always returns false.
llvm-svn: 252102
2015-11-04 23:59:18 +00:00
Eugene Zelenko ffec81ca00 Fix some Clang-tidy modernize warnings, other minor fixes.
Fixed warnings are: modernize-use-override, modernize-use-nullptr and modernize-redundant-void-arg.

Differential revision: http://reviews.llvm.org/D14312

llvm-svn: 252087
2015-11-04 22:32:32 +00:00
Tim Northover 2d4d161519 ARM: support .watchos_version_min and .tvos_version_min.
These MachO file directives are used by linkers and other tools to provide
compatibility information, much like the existing .ios_version_min and
.macosx_version_min.

llvm-svn: 251569
2015-10-28 22:36:05 +00:00
Michael Kuperstein 259f1508f0 [X86] Emit .cfi_escape GNU_ARGS_SIZE when adjusting the stack before calls
When outgoing function arguments are passed using push instructions, and EH
is enabled, we may need to indicate to the stack unwinder that the stack
pointer was adjusted before the call.

This should fix the exception handling issues in PR24792.

Differential Revision: http://reviews.llvm.org/D13132

llvm-svn: 249522
2015-10-07 07:01:31 +00:00
Rafael Espindola e3a20f57d9 Fix pr24486.
This extends the work done in r233995 so that now getFragment (in addition to
getSection) also works for variable symbols.

With that the existing logic to decide if a-b can be computed works even if
a or b are variables. Given that, the expression evaluation can avoid expanding
variables as aggressively and that in turn lets the relocation code see the
original variable.

In order for this to work with the asm streamer, there is now a dummy fragment
per section. It is used to assign a section to a symbol when no other fragment
exists.

This patch is a joint work by Maxim Ostapenko andy myself.

llvm-svn: 249303
2015-10-05 12:07:05 +00:00
Rafael Espindola 2f834372f4 Disallow assigning symbol a null section.
They are constructed without one and they can't go back, so this was
effectively dead code.

llvm-svn: 249220
2015-10-03 00:18:14 +00:00
Craig Topper 3c76c523e1 Cleanup places that passed SMLoc by const reference to pass it by value instead. NFC
llvm-svn: 248135
2015-09-20 23:35:59 +00:00
Yaron Keren 556b21aa10 Remove and forbid raw_svector_ostream::flush() calls.
After r244870 flush() will only compare two null pointers and return,
doing nothing but wasting run time. The call is not required any more
as the stream and its SmallString are always in sync.

Thanks to David Blaikie for reviewing.

llvm-svn: 244928
2015-08-13 18:12:56 +00:00
Yaron Keren a3668a3fcd Remove raw_svector_ostream::resync and users. It's no-op after r244870.
llvm-svn: 244888
2015-08-13 12:42:25 +00:00
Chandler Carruth 6fb9c087cb Fix a -Winconsistent-missing-override failure in the .intel_syntax
patch.

llvm-svn: 242890
2015-07-22 11:22:29 +00:00
Michael Kuperstein 23d952b611 [X86] Add .intel_syntax noprefix directive to intel-syntax x86 asm output
Patch by: michael.zuckerman@intel.com
Differential Revision: http://reviews.llvm.org/D11223

llvm-svn: 242886
2015-07-22 10:49:44 +00:00
David Majnemer 1305e2c0f5 [MC] Correctly escape .safeseh's symbol
This fixes PR24107.

llvm-svn: 242050
2015-07-13 18:51:15 +00:00
Colin LeMahieu 48a9b71f4a [MC] Adding prettyPrintAsm to MCTargetStreamer to allow targets to specialize how instructions are printed to asm.
llvm-svn: 240050
2015-06-18 20:43:22 +00:00
Matt Arsenault 8b643559d4 MC: Add target hook to control symbol quoting
llvm-svn: 239370
2015-06-09 00:31:39 +00:00
Rafael Espindola a869576008 Create a MCSymbolELF.
This create a MCSymbolELF class and moves SymbolSize since only ELF
needs a size expression.

This reduces the size of MCSymbol from 56 to 48 bytes.

llvm-svn: 238801
2015-06-02 00:25:12 +00:00
David Majnemer 4eecd30d19 [WinCOFF] Add support for the .safeseh directive
.safeseh adds an entry to the .sxdata section to register all the
appropriate functions which may handle an exception.  This entry is not
a relocation to the symbol but instead the symbol table index of the
function.

llvm-svn: 238641
2015-05-30 04:56:02 +00:00
Jim Grosbach 13760bd152 MC: Clean up MCExpr naming. NFC.
llvm-svn: 238634
2015-05-30 01:25:56 +00:00
Reid Kleckner 1d3d4adbb9 [WinEH] Emit EH tables for __CxxFrameHandler3 on 32-bit x86
Small (really small!) C++ exception handling examples work on 32-bit x86
now.

This change disables the use of .seh_* directives in WinException when
CFI is not in use. It also uses absolute symbol references in the tables
instead of imagerel32 relocations.

Also fixes a cache invalidation bug in MMI personality classification.

llvm-svn: 238575
2015-05-29 17:00:57 +00:00
Rafael Espindola 691a5adbdb We always have an InstPrinter.
llvm-svn: 238311
2015-05-27 12:13:06 +00:00
Rafael Espindola 0709a7bd1a Move alignment from MCSectionData to MCSection.
This starts merging MCSection and MCSectionData.

There are a few issues with the current split between MCSection and
MCSectionData.

* It optimizes the the not as important case. We want the production
of .o files to be really fast, but the split puts the information used
for .o emission in a separate data structure.

* The ELF/COFF/MachO hierarchy is not represented in MCSectionData,
leading to some ad-hoc ways to represent the various flags.

* It makes it harder to remember where each item is.

The attached patch starts merging the two by moving the alignment from
MCSectionData to MCSection.

Most of the patch is actually just dropping 'const', since
MCSectionData is mutable, but MCSection was not.

llvm-svn: 237936
2015-05-21 19:20:38 +00:00
Jim Grosbach 91df21f740 MC: Update MCCodeEmitter naming. NFC.
s/EncodeInstruction/encodeInstruction/

llvm-svn: 237469
2015-05-15 19:13:16 +00:00
Rafael Espindola 5682ce2ceb Simplify use of formatted_raw_ostream.
formatted_raw_ostream is a wrapper over another stream to add column and line
number tracking.

It is used only for asm printing.

This patch moves the its creation down to where we know we are printing
assembly. This has the following advantages:

* Simpler lifetime management: std::unique_ptr
* We don't compute column and line number of object files :-)

llvm-svn: 234535
2015-04-09 21:06:08 +00:00