Commit Graph

988 Commits

Author SHA1 Message Date
Daniel Sanders
11e78c2bff Bring back the ability opt out of padding zero-byte functions by not providing a nop instruction.
Summary: No test case since I'm not aware of an in-tree target that needs this.

Reviewers: hans

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32398

llvm-svn: 301311
2017-04-25 14:27:27 +00:00
Adrian Prantl
083e6a5b5c Don't emit CFI instructions at the end of a function
When functions are terminated by unreachable instructions, the last
instruction might trigger a CFI instruction to be generated. However,
emitting it would be be illegal since the function (and thus the FDE
the CFI is in) has already ended with the previous instruction.

Darwin's dwarfdump --verify --eh-frame complains about this and the
specification supports this.
Relevant bits from the DWARF 5 standard (6.4 Call Frame Information):

"[The] address_range [field in an FDE]: The number of bytes of
 program instructions described by this entry."

"Row creation instructions: [...]
 The new location value is always greater than the current one."
The first quotation implies that a CFI cannot describe a target
address outside of the enclosing FDE's range.

rdar://problem/26244988

Differential Revision: https://reviews.llvm.org/D32246

llvm-svn: 301219
2017-04-24 18:45:59 +00:00
Adrian Prantl
283833d022 Add a testcase for DIExpression(DW_OP_stack_value)
and relax the assertion that prohibited its emission.

This fixes the assertion failure uncovered by r301093.

llvm-svn: 301209
2017-04-24 18:11:38 +00:00
Hans Wennborg
9b9a5358dd Re-commit r301040 "X86: Don't emit zero-byte functions on Windows"
In addition to the original commit, tighten the condition for when to
pad empty functions to COFF Windows.  This avoids running into problems
when targeting e.g. Win32 AMDGPU, which caused test failures when this
was committed initially.

llvm-svn: 301047
2017-04-21 21:48:41 +00:00
Hans Wennborg
04593000d8 Revert r301040 "X86: Don't emit zero-byte functions on Windows"
This broke almost all bots. Reverting while fixing.

llvm-svn: 301041
2017-04-21 21:10:37 +00:00
Hans Wennborg
cb3e810714 X86: Don't emit zero-byte functions on Windows
Empty functions can lead to duplicate entries in the Guard CF Function
Table of a binary due to multiple functions sharing the same RVA,
causing the kernel to refuse to load that binary.

We had a terrific bug due to this in Chromium.

It turns out we were already doing this for Mach-O in certain
situations. This patch expands the code for that in
AsmPrinter::EmitFunctionBody() and renames
TargetInstrInfo::getNoopForMachoTarget() to simply getNoop() since it
seems it was used for not just Mach-O anyway.

Differential Revision: https://reviews.llvm.org/D32330

llvm-svn: 301040
2017-04-21 20:58:12 +00:00
Craig Topper
fc947bcfba [APInt] Use lshrInPlace to replace lshr where possible
This patch uses lshrInPlace to replace code where the object that lshr is called on is being overwritten with the result.

This adds an lshrInPlace(const APInt &) version as well.

Differential Revision: https://reviews.llvm.org/D32155

llvm-svn: 300566
2017-04-18 17:14:21 +00:00
Adrian Prantl
6825fb64e9 PR32382: Fix emitting complex DWARF expressions.
The DWARF specification knows 3 kinds of non-empty simple location
descriptions:
1. Register location descriptions
  - describe a variable in a register
  - consist of only a DW_OP_reg
2. Memory location descriptions
  - describe the address of a variable
3. Implicit location descriptions
  - describe the value of a variable
  - end with DW_OP_stack_value & friends

The existing DwarfExpression code is pretty much ignorant of these
restrictions. This used to not matter because we only emitted very
short expressions that we happened to get right by accident.  This
patch makes DwarfExpression aware of the rules defined by the DWARF
standard and now chooses the right kind of location description for
each expression being emitted.

This would have been an NFC commit (for the existing testsuite) if not
for the way that clang describes captured block variables. Based on
how the previous code in LLVM emitted locations, DW_OP_deref
operations that should have come at the end of the expression are put
at its beginning. Fixing this means changing the semantics of
DIExpression, so this patch bumps the version number of DIExpression
and implements a bitcode upgrade.

There are two major changes in this patch:

I had to fix the semantics of dbg.declare for describing function
arguments. After this patch a dbg.declare always takes the *address*
of a variable as the first argument, even if the argument is not an
alloca.

When lowering a DBG_VALUE, the decision of whether to emit a register
location description or a memory location description depends on the
MachineLocation — register machine locations may get promoted to
memory locations based on their DIExpression. (Future) optimization
passes that want to salvage implicit debug location for variables may
do so by appending a DW_OP_stack_value. For example:
  DBG_VALUE, [RBP-8]                        --> DW_OP_fbreg -8
  DBG_VALUE, RAX                            --> DW_OP_reg0 +0
  DBG_VALUE, RAX, DIExpression(DW_OP_deref) --> DW_OP_reg0 +0

All testcases that were modified were regenerated from clang. I also
added source-based testcases for each of these to the debuginfo-tests
repository over the last week to make sure that no synchronized bugs
slip in. The debuginfo-tests compile from source and run the debugger.

https://bugs.llvm.org/show_bug.cgi?id=32382
<rdar://problem/31205000>

Differential Revision: https://reviews.llvm.org/D31439

llvm-svn: 300522
2017-04-18 01:21:53 +00:00
Konstantin Zhuravlyov
dc77b2e960 Distinguish between code pointer size and DataLayout::getPointerSize() in DWARF info generation
llvm-svn: 300463
2017-04-17 17:41:25 +00:00
Andrew V. Tischenko
75745d0c3e This patch closes PR#32216: Better testing of schedule model instruction latencies/throughputs.
The details are here: https://reviews.llvm.org/D30941

llvm-svn: 300311
2017-04-14 07:44:23 +00:00
Peter Collingbourne
2e0ffe9858 Move llvm::canBeOmittedFromSymbolTable() to Analysis.
llvm-svn: 299182
2017-03-31 04:46:31 +00:00
Peter Collingbourne
d44a01aae6 CodeGen: Use the source filename as the argument to .file, rather than the module ID.
Using the module ID here is wrong for a couple of reasons:
1) The module ID is not persisted, so we can end up with different
   object file contents given the same input file (for example if the same
   file is accessed via different paths).
2) With ThinLTO the module ID field may contain the path to a bitcode file,
   which is incorrect, as the .file argument is supposed to contain the path to
   a source file.

Differential Revision: https://reviews.llvm.org/D30584

llvm-svn: 297853
2017-03-15 16:24:52 +00:00
Peter Collingbourne
7f6e2c97b8 Ensure that prefix data is preserved with subsections-via-symbols
On MachO platforms that use subsections-via-symbols dead code stripping will
drop prefix data. Unfortunately there is no great way to convey the relationship
between a function and its prefix data to the linker. We are forced to use a bit
of a hack: we give the prefix data it’s own symbol, and mark the actual function
entry an .alt_entry.

Patch by Moritz Angermann!

Differential Revision: https://reviews.llvm.org/D30770

llvm-svn: 297804
2017-03-15 04:18:16 +00:00
Dean Michael Berris
7e8eea429f [XRay] Allow logging the first argument of a function call.
Summary:
Functions with the "xray-log-args" attribute will have a special XRay sled kind
emitted, for compiler-rt to copy any call arguments to your logging handler.

For practical and performance reasons, only the first argument is supported, and
only up to 64 bits.

Reviewers: dberris

Reviewed By: dberris

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29702

llvm-svn: 296998
2017-03-06 06:48:56 +00:00
Justin Bogner
369ba753aa OptDiag: Summarize the instruction count in asm-printer
Add an optimization remark to asm-printer that summarizes the number
of instructions emitted per function.

llvm-svn: 296053
2017-02-24 00:19:22 +00:00
Eugene Zelenko
d96089b248 [MC] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
Same changes in files affected by reduced MC headers dependencies.

llvm-svn: 295009
2017-02-14 00:33:36 +00:00
Simon Dardis
2e8cdbd795 [DebugInfo] Rename EmitDebugValue to EmitDebugThreadLocal (NFC)
As pointed out by David Blaikie in the post commit review of
r292624, EmitDebugValue should be called EmitDebugThreadLocal.

llvm-svn: 294500
2017-02-08 19:03:46 +00:00
Petar Jovanovic
dbb39356b4 [mips] Fix debug information for __thread variable
This patch fixes debug information for __thread variable on Mips
using .dtprelword and .dtpreldword directives.

Patch by Aleksandar Beserminji.

Differential Revision: http://reviews.llvm.org/D28770

llvm-svn: 292624
2017-01-20 17:53:30 +00:00
Teresa Johnson
2d384ac381 Don't create a comdat group for a dropped def with initializer
Non-prevailing weak/linkonce odr symbols will be dropped by ThinLTO to
available_externally when possible. If they had an initializer in the
global_ctors list, a comdat group was being created. This code
already had logic to skip available_externally defs, but now the
EliminateAvailableExternally pass will drop these symbols to
declarations earlier. Change the check to skip all declarations for
linker (which includes available_externally along with declarations).

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28737

llvm-svn: 292408
2017-01-18 16:58:43 +00:00
Joerg Sonnenberger
83963995c6 PR 31534: When emitting both DWARF unwind tables and debug information,
do not use .cfi_sections. This requires checking if any non-declaration
function in the module needs an unwind table.

llvm-svn: 291172
2017-01-05 20:55:28 +00:00
Dean Michael Berris
f7e7b938ea [XRay] Merge instrumentation point table emission code into AsmPrinter.
Summary:
No need to have this per-architecture.  While there, unify 32-bit ARM's
behaviour with what changed elsewhere and start function names lowercase
as per the coding standards.  Individual entry emission code goes to the
entry's own class.

Fully tested on amd64, cross-builds on both ARMs and PowerPC.

Reviewers: dberris

Subscribers: aemerson, llvm-commits

Differential Revision: https://reviews.llvm.org/D28209

llvm-svn: 290858
2017-01-03 04:30:21 +00:00
Keno Fischer
f7d84ee6ff Reapply "[CodeGen] Fix invalid DWARF info on Win64"
This reapplies rL289013 (reverted in rL289014) with the fixes identified
in D21731. Should hopefully pass the buildbots this time.

llvm-svn: 290809
2017-01-02 03:00:19 +00:00
Adrian Prantl
49797ca6be Refactor the DIExpression fragment query interface (NFC)
... so it becomes available to DIExpressionCursor.

llvm-svn: 290322
2016-12-22 05:27:12 +00:00
Stephan Bergmann
17c7f70362 Replace APFloatBase static fltSemantics data members with getter functions
At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.

Differential Revision: https://reviews.llvm.org/D26671

llvm-svn: 289647
2016-12-14 11:57:17 +00:00
Keno Fischer
d4ea4c18f1 Revert "[CodeGen] Fix invalid DWARF info on Win64"
Appears to break on build bots. Reverting pending investigation.

llvm-svn: 289014
2016-12-08 01:56:23 +00:00
Keno Fischer
460218fb7d [CodeGen] Fix invalid DWARF info on Win64
The relocations for `DIEEntry::EmitValue` were wrong for Win64
(emitting FK_Data_4 instead of FK_SecRel_4). This corrects that
oversight so that the DWARF data is correct in Win64 COFF files.

Fixes PR15393.

Patch by Jameson Nash <jameson@juliacomputing.com> based on a patch
by David Majnemer.

Differential Revision: https://reviews.llvm.org/D21731

llvm-svn: 289013
2016-12-08 01:40:21 +00:00
Adrian Prantl
941fa7588b [DIExpression] Introduce a dedicated DW_OP_LLVM_fragment operation
so we can stop using DW_OP_bit_piece with the wrong semantics.

The entire back story can be found here:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20161114/405934.html

The gist is that in LLVM we've been misinterpreting DW_OP_bit_piece's
offset field to mean the offset into the source variable rather than
the offset into the location at the top the DWARF expression stack. In
order to be able to fix this in a subsequent patch, this patch
introduces a dedicated DW_OP_LLVM_fragment operation with the
semantics that we used to apply to DW_OP_bit_piece, which is what we
actually need while inside of LLVM. This patch is complete with a
bitcode upgrade for expressions using the old format. It does not yet
fix the DWARF backend to use DW_OP_bit_piece correctly.

Implementation note: We discussed several options for implementing
this, including reserving a dedicated field in DIExpression for the
fragment size and offset, but using an custom operator at the end of
the expression works just fine and is more efficient because we then
only pay for it when we need it.

Differential Revision: https://reviews.llvm.org/D27361
rdar://problem/29335809

llvm-svn: 288683
2016-12-05 18:04:47 +00:00
Dan Gohman
734c59d501 [MC] Refactor emitELFSize to make usage more consistent. NFC.
Move the cast<MCSymbolELF> inside emitELFSize, so that: 
 - it's done in one place instead of at each call
 - it's more consistent with similar functions like EmitCOFFSafeSEH
 - ambiguity between cast<> and dyn_cast<> is avoided (which also
   eliminates an unnecessary dyn_cast call)

This also makes it easier to experiment with using ".size" directives on
non-ELF targets.

llvm-svn: 288437
2016-12-01 23:39:08 +00:00
Matthias Braun
d0ee66c2e9 Move most EH from MachineModuleInfo to MachineFunction
Recommitting r288293 with some extra fixes for GlobalISel code.

Most of the exception handling members in MachineModuleInfo is actually
per function data (talks about the "current function") so it is better
to keep it at the function instead of the module.

This is a necessary step to have machine module passes work properly.

Also:
- Rename TidyLandingPads() to tidyLandingPads()
- Use doxygen member groups instead of "//===- EH ---"... so it is clear
  where a group ends.
- I had to add an ugly const_cast at two places in the AsmPrinter
  because the available MachineFunction pointers are const, but the code
  wants to call tidyLandingPads() in between
  (markFunctionEnd()/endFunction()).

Differential Revision: https://reviews.llvm.org/D27227

llvm-svn: 288405
2016-12-01 19:32:15 +00:00
Eric Christopher
e70b7c3dfb Temporarily Revert "Move most EH from MachineModuleInfo to MachineFunction"
This apprears to have broken the global isel bot:
http://lab.llvm.org:8080/green/job/clang-stage1-cmake-RA-globalisel_build/5174/console

This reverts commit r288293.

llvm-svn: 288322
2016-12-01 07:50:12 +00:00
Matthias Braun
ed14cb0604 Move most EH from MachineModuleInfo to MachineFunction
Most of the exception handling members in MachineModuleInfo is actually
per function data (talks about the "current function") so it is better
to keep it at the function instead of the module.

This is a necessary step to have machine module passes work properly.

Also:
- Rename TidyLandingPads() to tidyLandingPads()
- Use doxygen member groups instead of "//===- EH ---"... so it is clear
  where a group ends.
- I had to add an ugly const_cast at two places in the AsmPrinter
  because the available MachineFunction pointers are const, but the code
  wants to call tidyLandingPads() in between
  (markFunctionEnd()/endFunction()).

Differential Revision: https://reviews.llvm.org/D27227

llvm-svn: 288293
2016-11-30 23:49:01 +00:00
Matthias Braun
f23ef437cc Move FrameInstructions from MachineModuleInfo to MachineFunction
This is per function data so it is better kept at the function instead
of the module.

This is a necessary step to have machine module passes work properly.

Differential Revision: https://reviews.llvm.org/D27185

llvm-svn: 288291
2016-11-30 23:48:42 +00:00
Greg Clayton
e65439797a Rely on a single DWARF version instead of having two copies
This patch makes AsmPrinter less reliant on DwarfDebug by relying on the DWARF version in the AsmPrinter's MCStreamer's MCContext. This allows us to remove the redundant DWARF version from DwarfDebug. It also lets us change code that used to access the AsmPrinter's DwarfDebug just to get to the DWARF version by changing the DWARF version accessor on AsmPrinter so that it grabs the version from its MCStreamer's MCContext.

Differential Revision: https://reviews.llvm.org/D27032

llvm-svn: 287839
2016-11-23 23:30:37 +00:00
Tim Northover
b64fb453ea CodeGen: simplify TargetMachine::getSymbol interface. NFC.
No-one actually had a mangler handy when calling this function, and
getSymbol itself went most of the way towards getting its own mangler
(with a local TLOF variable) so forcing all callers to supply one was
just extra complication.

llvm-svn: 287645
2016-11-22 16:17:20 +00:00
Shoaib Meenai
106e05a0e8 [AsmPrinter] Enable codeview for windows-itanium
Enable codeview emission for windows-itanium targets. Co-opt an existing
test (which is derived from a C source file and should therefore be
identical across the Itanium and MS ABIs).

Differential Revision: https://reviews.llvm.org/D26693

llvm-svn: 287567
2016-11-21 20:13:32 +00:00
Matthias Braun
9f15a79e5d Timer: Track name and description.
The previously used "names" are rather descriptions (they use multiple
words and contain spaces), use short programming language identifier
like strings for the "names" which should be used when exporting to
machine parseable formats.

Also removed a unused TimerGroup from Hexxagon.

Differential Revision: https://reviews.llvm.org/D25583

llvm-svn: 287369
2016-11-18 19:43:18 +00:00
Eric Christopher
445c952bd0 Tidy the calls to getCurrentSection().first -> getCurrentSectionOnly to help
readability a bit.

llvm-svn: 284202
2016-10-14 05:47:37 +00:00
Reid Kleckner
f9dddec21c Improve DEBUG_VALUE assembly comments for spilled bitpieces
Previously we would give up when we saw the bitpiece DWARF expression
and print "[complex expression]" when actually we handled bitpiece
expressions outside the loop.

llvm-svn: 283355
2016-10-05 18:36:02 +00:00
Mehdi Amini
7410717a62 Use StringRef in Registry API (NFC)
llvm-svn: 283039
2016-10-01 15:44:54 +00:00
Eric Christopher
e8d141c675 Remove getTargetTriple and update all uses to use the Triple off
of the TargetMachine. NFC.

llvm-svn: 283002
2016-10-01 01:50:33 +00:00
Dean Michael Berris
4640154446 [XRay] ARM 32-bit no-Thumb support in LLVM
This is a port of XRay to ARM 32-bit, without Thumb support yet. The XRay instrumentation support is moving up to AsmPrinter.
This is one of 3 commits to different repositories of XRay ARM port. The other 2 are:

https://reviews.llvm.org/D23932 (Clang test)
https://reviews.llvm.org/D23933 (compiler-rt)

Differential Revision: https://reviews.llvm.org/D23931

llvm-svn: 281878
2016-09-19 00:54:35 +00:00
Eric Christopher
4367c7fb9a Move the Mangler from the AsmPrinter down to TLOF and clean up the
TLOF API accordingly.

llvm-svn: 281708
2016-09-16 07:33:15 +00:00
Renato Golin
049f387112 Revert "[XRay] ARM 32-bit no-Thumb support in LLVM"
And associated commits, as they broke the Thumb bots.

This reverts commit r280935.
This reverts commit r280891.
This reverts commit r280888.

llvm-svn: 280967
2016-09-08 17:10:39 +00:00
Dean Michael Berris
17d94e279e [XRay] ARM 32-bit no-Thumb support in LLVM
This is a port of XRay to ARM 32-bit, without Thumb support yet. The XRay instrumentation support is moving up to AsmPrinter.
This is one of 3 commits to different repositories of XRay ARM port. The other 2 are:

1. https://reviews.llvm.org/D23932 (Clang test)
2. https://reviews.llvm.org/D23933 (compiler-rt)

Differential Revision: https://reviews.llvm.org/D23931

llvm-svn: 280888
2016-09-08 00:19:04 +00:00
Richard Smith
8c3fbdc6c4 Revert r279564. It introduces undefined behavior (binding a reference to a
dereferenced null pointer) in MachineModuleInfo::MachineModuleInfo that causes
-Werror builds (including several buildbots) to fail.

llvm-svn: 279580
2016-08-23 22:08:27 +00:00
Matthias Braun
4c1f1f120c CodeGen: Remove MachineFunctionAnalysis => Enable (Machine)ModulePasses
Re-apply this commit with the deletion of a MachineFunction delegated to
a separate pass to avoid use after free when doing this directly in
AsmPrinter.

This patch removes the MachineFunctionAnalysis. Instead we keep a
map from IR Function to MachineFunction in the MachineModuleInfo.

This allows the insertion of ModulePasses into the codegen pipeline
without breaking it because the MachineFunctionAnalysis gets dropped
before a module pass.

Peak memory should stay unchanged without a ModulePass in the codegen
pipeline: Previously the MachineFunction was freed at the end of a codegen
function pipeline because the MachineFunctionAnalysis was dropped; With
this patch the MachineFunction is freed after the AsmPrinter has
finished.

Differential Revision: http://reviews.llvm.org/D23736

llvm-svn: 279564
2016-08-23 20:58:29 +00:00
Matthias Braun
7f66202d38 Revert "(HEAD -> master, origin/master, origin/HEAD) CodeGen: Remove MachineFunctionAnalysis => Enable (Machine)ModulePasses"
Reverting while tracking down a use after free.

This reverts commit r279502.

llvm-svn: 279503
2016-08-23 05:17:11 +00:00
Matthias Braun
fd936841eb CodeGen: Remove MachineFunctionAnalysis => Enable (Machine)ModulePasses
This patch removes the MachineFunctionAnalysis. Instead we keep a
map from IR Function to MachineFunction in the MachineModuleInfo.

This allows the insertion of ModulePasses into the codegen pipeline
without breaking it because the MachineFunctionAnalysis gets dropped
before a module pass.

Peak memory should stay unchanged without a ModulePass in the codegen
pipeline: Previously the MachineFunction was freed at the end of a codegen
function pipeline because the MachineFunctionAnalysis was dropped; With
this patch the MachineFunction is freed after the AsmPrinter has
finished.

Differential Revision: http://reviews.llvm.org/D23736

llvm-svn: 279502
2016-08-23 03:20:09 +00:00
Justin Bogner
cd1d5aaf2e Replace a few more "fall through" comments with LLVM_FALLTHROUGH
Follow up to r278902. I had missed "fall through", with a space.

llvm-svn: 278970
2016-08-17 20:30:52 +00:00
Davide Italiano
151e5be5ea [MC] Delete use of *structors_used.
Jim Grosbach and Kevin Enderby think those are not used anymore.
Originally submitted by: Rafael Espindola

llvm-svn: 277973
2016-08-08 03:30:01 +00:00
David Majnemer
d536f2328e [ConstnatFolding] Teach the folder how to fold ConstantVector
A ConstantVector can have ConstantExpr operands and vice versa.
However, the folder had no ability to fold ConstantVectors which, in
some cases, was an optimization barrier.

Instead, rephrase the folder in terms of Constants instead of
ConstantExprs and teach callers how to deal with failure.

llvm-svn: 277099
2016-07-29 03:27:26 +00:00
Matthias Braun
941a705b7b MachineFunction: Return reference for getFrameInfo(); NFC
getFrameInfo() never returns nullptr so we should use a reference
instead of a pointer.

llvm-svn: 277017
2016-07-28 18:40:00 +00:00
Matthias Braun
07985809ab AsmPrinter: Fix emitKill() not flush()ing a raw_string_ostream
llvm-svn: 274951
2016-07-09 00:18:43 +00:00
Eric Christopher
0b6537e6e5 80-column and comment fixups.
llvm-svn: 274335
2016-07-01 06:07:31 +00:00
Duncan P. N. Exon Smith
9cfc75c214 CodeGen: Use MachineInstr& in TargetInstrInfo, NFC
This is mostly a mechanical change to make TargetInstrInfo API take
MachineInstr& (instead of MachineInstr* or MachineBasicBlock::iterator)
when the argument is expected to be a valid MachineInstr.  This is a
general API improvement.

Although it would be possible to do this one function at a time, that
would demand a quadratic amount of churn since many of these functions
call each other.  Instead I've done everything as a block and just
updated what was necessary.

This is mostly mechanical fixes: adding and removing `*` and `&`
operators.  The only non-mechanical change is to split
ARMBaseInstrInfo::getOperandLatencyImpl out from
ARMBaseInstrInfo::getOperandLatency.  Previously, the latter took a
`MachineInstr*` which it updated to the instruction bundle leader; now,
the latter calls the former either with the same `MachineInstr&` or the
bundle leader.

As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.

Note: I updated WebAssembly, Lanai, and AVR (despite being
off-by-default) since it turned out to be easy.  I couldn't run tests
for AVR since llc doesn't link with it turned on.

llvm-svn: 274189
2016-06-30 00:01:54 +00:00
Rafael Espindola
b1556c42ce Use isPositionIndependent in a few more places.
I think this converts all the simple cases that really just care about
the generated code being position independent or not. The remaining
uses are a bit more complicated and are checking things like "is this
a library or executable" or "can this symbol be preempted".

llvm-svn: 274055
2016-06-28 20:13:36 +00:00
Rafael Espindola
0db11db560 Move isPositionIndependent up to AsmPrinter.
Use it in ppc too.

llvm-svn: 273877
2016-06-27 14:19:45 +00:00
Peter Collingbourne
6d88fde3af IR: Introduce Module::global_objects().
This is a convenience iterator that allows clients to enumerate the
GlobalObjects within a Module.

Also start using it in a few places where it is obviously the right thing
to use.

Differential Revision: http://reviews.llvm.org/D21580

llvm-svn: 273470
2016-06-22 20:29:42 +00:00
Joerg Sonnenberger
2298203056 doesSetDirectiveSuppressesReloc -> doesSetDirectiveSuppressReloc, the
former is grammatically incorrect.

llvm-svn: 273100
2016-06-18 23:25:37 +00:00
Peter Collingbourne
96efdd6107 IR: Introduce local_unnamed_addr attribute.
If a local_unnamed_addr attribute is attached to a global, the address
is known to be insignificant within the module. It is distinct from the
existing unnamed_addr attribute in that it only describes a local property
of the module rather than a global property of the symbol.

This attribute is intended to be used by the code generator and LTO to allow
the linker to decide whether the global needs to be in the symbol table. It is
possible to exclude a global from the symbol table if three things are true:
- This attribute is present on every instance of the global (which means that
  the normal rule that the global must have a unique address can be broken without
  being observable by the program by performing comparisons against the global's
  address)
- The global has linkonce_odr linkage (which means that each linkage unit must have
  its own copy of the global if it requires one, and the copy in each linkage unit
  must be the same)
- It is a constant or a function (which means that the program cannot observe that
  the unique-address rule has been broken by writing to the global)

Although this attribute could in principle be computed from the module
contents, LTO clients (i.e. linkers) will normally need to be able to compute
this property as part of symbol resolution, and it would be inefficient to
materialize every module just to compute it.

See:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160509/356401.html
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160516/356738.html
for earlier discussion.

Part of the fix for PR27553.

Differential Revision: http://reviews.llvm.org/D20348

llvm-svn: 272709
2016-06-14 21:01:22 +00:00
Nirav Dave
f8d00d5cac Fix BSS global handling in AsmPrinter
Change EmitGlobalVariable to check final assembler section is in BSS
before using .lcomm/.comm directive. This prevents globals from being
put into .bss erroneously when -data-sections is used.

This fixes PR26570.

Reviewers: echristo, rafael

Subscribers: llvm-commits, mehdi_amini

Differential Revision: http://reviews.llvm.org/D21146

llvm-svn: 272674
2016-06-14 15:09:30 +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
Peter Collingbourne
5973bc8a82 CodeGen: Move the call to DwarfDebug::beginModule() out of the constructor.
This gives AsmPrinter a chance to initialize its DD field before
we call beginModule(), which is about to start using it.

Differential Revision: http://reviews.llvm.org/D20413

llvm-svn: 270258
2016-05-20 19:35:35 +00:00
Rafael Espindola
e64619ce6e Fail early on unknown appending linkage variables.
In practice only a few well known appending linkage variables work.

Currently if codegen sees an unknown appending linkage variable it will
just print it as a regular global. That is wrong as the symbol in the
produced object file has different semantics as the one provided by the
appending linkage.

This just errors early instead of producing a broken .o.

llvm-svn: 269706
2016-05-16 21:14:24 +00:00
Rafael Espindola
83658d6e7a Return a StringRef from getSection.
This is similar to how getName is handled.

llvm-svn: 269218
2016-05-11 18:21:59 +00:00
Rafael Espindola
610a4e916e Merge two unreachable cases.
llvm-svn: 269189
2016-05-11 14:41:30 +00:00
Peter Collingbourne
265ebd7d70 CodeGen: Use PLT relocations for relative references to unnamed_addr functions.
The relative vtable ABI (PR26723) needs PLT relocations to refer to virtual
functions defined in other DSOs. The unnamed_addr attribute means that the
function's address is not significant, so we're allowed to substitute it
with the address of a PLT entry.

Also includes a bonus feature: addends for COFF image-relative references.

Differential Revision: http://reviews.llvm.org/D17938

llvm-svn: 267211
2016-04-22 20:40:10 +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
Dmitry Polukhin
a1feff7024 [GCC] Attribute ifunc support in llvm
This patch add support for GCC attribute((ifunc("resolver"))) for
targets that use ELF as object file format. In general ifunc is a
special kind of function alias with type @gnu_indirect_function. Patch
for Clang http://reviews.llvm.org/D15524

Differential Revision: http://reviews.llvm.org/D15525

llvm-svn: 265667
2016-04-07 12:32:19 +00:00
Dmitry Polukhin
a3d5b0b218 [IFUNC] Use GlobalIndirectSymbol when aliases and ifuncs have something similar
Second part extracted from http://reviews.llvm.org/D15525

Use GlobalIndirectSymbol in all cases when aliases and ifuncs have
something in common.

Differential Revision: http://reviews.llvm.org/D18754

llvm-svn: 265382
2016-04-05 08:47:51 +00:00
Tim Shen
800ed436e5 [AsmPrinter] Print aliases in topological order
Print aliases in topological order, that is, for any alias a = b,
b must be printed before a. This is because on some targets (e.g. PowerPC)
linker expects aliases in such an order to generate correct TOC information.

GCC also prints aliases in topological order.

llvm-svn: 265064
2016-03-31 22:08:19 +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
Duncan P. N. Exon Smith
f9ab416d70 WIP: CodeGen: Use MachineInstr& in MachineInstrBundle.h, NFC
Update APIs in MachineInstrBundle.h to take and return MachineInstr&
instead of MachineInstr* when the instruction cannot be null.  Besides
being a nice cleanup, this is tacking toward a fix for PR26753.

llvm-svn: 262141
2016-02-27 17:05:33 +00:00
David Majnemer
a3ea407d48 [X86] Use the correct alignment for COMDAT constant pool entries
COFF doesn't have sections with mergeable contents.  Instead, each
constant pool entry ends up in a COMDAT section.  The linker, when
choosing between COMDAT sections, doesn't choose the max alignment of
the two sections.  You just get whatever alignment was on the section.

If one constant needed a higher alignment in one object file from
another one, then we will get into trouble if the linker chooses the
lower alignment one.

Instead, lets promote the alignment of the constant pool entry to make
sure we don't use an under aligned constant with an instruction which
assumed otherwise.

This fixes PR26680.

llvm-svn: 261462
2016-02-21 01:30:30 +00:00
Reid Kleckner
70f5bc99b6 Rename WinCodeViewLineTables to CodeViewDebug, similar to DwarfDebug
Soon it will be responsible for more than line tables.

Reviewers: majnemer

Differential Revision: http://reviews.llvm.org/D16199

llvm-svn: 257792
2016-01-14 19:25:04 +00:00
Chih-Hung Hsieh
578864007b [TLS] New lower emutls pass, fix linkage bugs.
Previous implementation in http://reviews.llvm.org/D10522
created external references to __emutls_v.* variables.
Such references are inaccurate and cannot be handled by
all linkers, e.g. Android dynamic and gold linkers for aarch64.

Now a new LowerEmuTLS pass to go through all global variables,
and add emutls_v.* and emutls_t.* variables.
These __emutls* variables have the same linkage and
visibility as the associated user defined TLS variable.

Also removed old code that dump __emutls* variables in AsmPrinter.cpp,
and updated TLS unit tests.

Differential Revision: http://reviews.llvm.org/D15300

llvm-svn: 257718
2016-01-13 23:56:37 +00:00
Matthias Braun
4cc3421a24 AsmPrinter: Fix wrong OS X versions being emitted for darwin triples
The version numbers of the darwin kernel are different from the version
numbers of OS X, so we need adjustments if we had "*-*-darwin" triples.
Use the existing utility functions in TargetTriple for this.

Fixes rdar://22056966

Differential Revision: http://reviews.llvm.org/D14601

llvm-svn: 257555
2016-01-13 01:18:13 +00:00
David Majnemer
11234ed7d3 [CodeGen] Use generic printAsOperand machinery instead of hand rolling it
We already know how to properly print out basic blocks in
printAsOperand, we should not roll it ourselves in
AsmPrinter::EmitBasicBlockStart.  No functionality change is intended.

llvm-svn: 256413
2015-12-25 09:37:26 +00:00
Keno Fischer
4eccf11373 [ASMPrinter] Fix missing handling of DW_OP_bit_piece
In r256077, I added printing for DIExpressions in DEBUG_VALUE comments,
but neglected to handle DW_OP_bit_piece operands. Thanks to
Mikael Holmen and Joerg Sonnenberger for spotting this.

llvm-svn: 256236
2015-12-22 07:14:50 +00:00
Keno Fischer
00cbf9a69a Clean up the processing of dbg.value in various places
Summary:
First up is instcombine, where in the dbg.declare -> dbg.value conversion,
the llvm.dbg.value needs to be called on the actual loaded value, rather
than the address (since the whole point of this transformation is to be
able to get rid of the alloca). Further, now that that's cleaned up, we
can remove a hack in the backend, that would add an implicit OP_deref if
the argument to dbg.value was an alloca. This stems from before the
existence of DIExpression and is no longer necessary since the deref can
be expressed explicitly.

Now, in order to make sure that the tests pass with this change, we need to
correct the printing of DEBUG_VALUE comments to take into account the
expression, which wasn't taken into account before.

Unfortunately, for both these changes, there were a number of incorrect
test cases (mostly the wrong number of DW_OP_derefs, but also a couple
where the test itself was broken more badly). aprantl and I have gone
through and adjusted these test case in order to make them pass with
these fixes and in some cases to make sure they're actually testing
what they are meant to test.

Reviewers: aprantl

Subscribers: dsanders

Differential Revision: http://reviews.llvm.org/D14186

llvm-svn: 256077
2015-12-19 02:02:44 +00:00
Justin Bogner
3135ba9b38 AsmPrinter: Use emitGlobalConstantFP to emit elements of constant data
It's strange to duplicate the logic for emitting FP values into
emitGlobalConstantDataSequential, and it's even stranger that we end
up printing the verbose assembly comments differently between the two
paths. Just call into emitGlobalConstantFP rather than crudely
duplicating its logic.

llvm-svn: 254988
2015-12-08 02:37:48 +00:00
Evgeniy Stepanov
2bb9c5ca22 Emit function alias to data as a function symbol.
CFI emits jump slots for indirect functions as a byte array
constant, and declares function-typed aliases to these constants.

This change fixes AsmPrinter to emit these aliases as function
symbols and not data symbols.

llvm-svn: 254674
2015-12-04 00:45:43 +00:00
Justin Bogner
8d6f4e36e8 AsmPrinter: Simplify emitting FP elements in sequential data. NFC
Use APFloat APIs here Rather than manually type-punning through
unions.

llvm-svn: 254664
2015-12-03 23:28:35 +00:00
Rafael Espindola
449711cb36 Stop producing .data.rel sections.
If a section is rw, it is irrelevant if the dynamic linker will write to
it or not.

It looks like llvm implemented this because gcc was doing it. It looks
like gcc implemented this in the hope that it would put all the
relocated items close together and speed up the dynamic linker.

There are two problem with this:
* It doesn't work. Both bfd and gold will map .data.rel to .data and
  concatenate the input sections in the order they are seen.
* If we want a feature like that, it can be implemented directly in the
  linker since it knowns where the dynamic relocations are.

llvm-svn: 253436
2015-11-18 06:02:15 +00:00
Dan Gohman
7aa4abac24 Use TargetRegisterInfo for printing MachineOperand register comments
Several places in AsmPrinter.cpp print comments describing MachineOperand
registers using MCRegisterInfo, which uses MCOperand-oriented names. This
doesn't work for targets that use virtual registers exclusively, as
WebAssembly does, since virtual registers are represented and printed
differently.

This patch preserves what seems to be the spirit of r229978, avoiding the
use of TM.getSubtargetImpl(), while still using MachineOperand-oriented
printing for MachineOperands.

Differential Revision: http://reviews.llvm.org/D14709

llvm-svn: 253338
2015-11-17 16:01:28 +00:00
Rafael Espindola
65e4902156 Drop prelink support.
The way prelink used to work was

* The compiler decides if a given section only has relocations that
are know to point to the same DSO. If so, it names it
.data.rel.ro.local<something>.
* The static linker puts all of these together.
* The prelinker program assigns addresses to each library and resolves
the local relocations.

There are many problems with this:
* It is incompatible with address space randomization.
* The information passed by the compiler is redundant. The linker
knows if a given relocation is in the same DSO or not. If could sort
by that if so desired.
* There are newer ways of speeding up DSO (gnu hash for example).
* Even if we want to implement this again in the compiler, the previous
  implementation is pretty broken. It talks about relocations that are
  "resolved by the static linker". If they are resolved, there are none
  left for the prelinker. What one needs to track is if an expression
  will require only dynamic relocations that point to the same DSO.

At this point it looks like the prelinker is an historical curiosity.
For example, fedora has retired it because it failed to build for two
releases
(http://pkgs.fedoraproject.org/cgit/prelink.git/commit/?id=eb43100a8331d91c801ee3dcdb0a0bb9babfdc1f)

This patch removes support for it. That is, it stops printing the
".local" sections.

llvm-svn: 253280
2015-11-17 00:51:23 +00:00
Akira Hatanaka
b11ef0897c Reduce the size of MCRelaxableFragment.
MCRelaxableFragment previously kept a copy of MCSubtargetInfo and
MCInst to enable re-encoding the MCInst later during relaxation. A copy
of MCSubtargetInfo (instead of a reference or pointer) was needed
because the feature bits could be modified by the parser.

This commit replaces the MCSubtargetInfo copy in MCRelaxableFragment
with a constant reference to MCSubtargetInfo. The copies of
MCSubtargetInfo are kept in MCContext, and the target parsers are now
responsible for asking MCContext to provide a copy whenever the feature
bits of MCSubtargetInfo have to be toggled.
 
With this patch, I saw a 4% reduction in peak memory usage when I
compiled verify-uselistorder.lto.bc using llc.

rdar://problem/21736951

Differential Revision: http://reviews.llvm.org/D14346

llvm-svn: 253127
2015-11-14 06:35:56 +00:00
Rafael Espindola
43e2e251ea Delete dead code.
llvm-svn: 251960
2015-11-03 18:55:58 +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
Joseph Tremoulet
3d0fbf1d74 [CodeGen] Mark setjmp/catchret MBBs address-taken
Summary:
This ensures that BranchFolding (and similar) won't remove these blocks.

Also allow AsmPrinter::EmitBasicBlockStart to process MBBs which are
address-taken but do not have BBs that are address-taken, since otherwise
its call to getAddrLabelSymbolTableToEmit would fail an assertion on such
blocks.  I audited the other callers of getAddrLabelSymbolTableToEmit
(and getAddrLabelSymbol); they all have BBs known to be address-taken
except for the call through getAddrLabelSymbol from
WinException::create32bitRef; that call is actually now unreachable, so
I've removed it and updated the signature of create32bitRef.

This fixes PR25168.

Reviewers: majnemer, andrew.w.kaylor, rnk

Subscribers: pgavlin, llvm-commits

Differential Revision: http://reviews.llvm.org/D13774

llvm-svn: 251113
2015-10-23 15:06:05 +00:00
David Majnemer
a80c151286 [WinEH] Teach AsmPrinter about funclets
Summary:
Funclets have been turned into functions by the time they hit the object
file.  Make sure that they have decent names for the symbol table and
CFI directives explaining how to reason about their prologues.

Differential Revision: http://reviews.llvm.org/D13261

llvm-svn: 248824
2015-09-29 20:12:33 +00:00
Reid Kleckner
c71d6275ca [WinEH] Fix ip2state table emission with funclets
Previously we were hijacking the old LandingPadInfo data structures to
communicate our state numbers. Now we don't need that anymore.

llvm-svn: 248763
2015-09-28 23:56:30 +00:00
Reid Kleckner
0e2882345d [WinEH] Add some support for code generating catchpad
We can now run 32-bit programs with empty catch bodies.  The next step
is to change PEI so that we get funclet prologues and epilogues.

llvm-svn: 246235
2015-08-27 23:27:47 +00:00
John Brawn
75fc09ddba Redo "Make global aliases have symbol size equal to their type"
r242520 was reverted in r244313 as the expected behaviour of the alias
attribute in C is that the alias has the same size as the aliasee. However
we can re-introduce adding the size on the alias when the aliasee does not,
from a source code or object perspective, exist as a discrete entity. This
happens when the aliasee is not a symbol, or when that symbol is private.

Differential Revision: http://reviews.llvm.org/D11943

llvm-svn: 244752
2015-08-12 15:05:39 +00:00
John Brawn
64e5a66794 Revert "Make global aliases have symbol size equal to their type"
This reverts r242520, as it caused pr24379. Also removes part of the test added
by r243874 that checks the size of alias symbols.

llvm-svn: 244313
2015-08-07 10:56:21 +00:00
Reid Kleckner
12d2c12023 If the "CodeView" module flag is set, emit codeview instead of DWARF
Summary:
Emit both DWARF and CodeView if "CodeView" and "Dwarf Version" module
flags are set.

Reviewers: majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11756

llvm-svn: 244158
2015-08-05 22:26:20 +00:00
Chih-Hung Hsieh
1e859582d6 Implement target independent TLS compatible with glibc's emutls.c.
The 'common' section TLS is not implemented.
Current C/C++ TLS variables are not placed in common section.
DWARF debug info to get the address of TLS variables is not generated yet.

clang and driver changes in http://reviews.llvm.org/D10524

  Added -femulated-tls flag to select the emulated TLS model,
  which will be used for old targets like Android that do not
  support ELF TLS models.

Added TargetLowering::LowerToTLSEmulatedModel as a target-independent
function to convert a SDNode of TLS variable address to a function call
to __emutls_get_address.

Added into lib/Target/*/*ISelLowering.cpp to call LowerToTLSEmulatedModel
for TLSModel::Emulated. Although all targets supporting ELF TLS models are
enhanced, emulated TLS model has been tested only for Android ELF targets.
Modified AsmPrinter.cpp to print the emutls_v.* and emutls_t.* variables for
emulated TLS variables.
Modified DwarfCompileUnit.cpp to skip some DIE for emulated TLS variabls.

TODO: Add proper DIE for emulated TLS variables.
      Added new unit tests with emulated TLS.

Differential Revision: http://reviews.llvm.org/D10522

llvm-svn: 243438
2015-07-28 16:24:05 +00:00
Mehdi Amini
26d481311a Remove access to the DataLayout in the TargetMachine
Summary:
Replace getDataLayout() with a createDataLayout() method to make
explicit that it is intended to create a DataLayout only and not
accessing it for other purpose.

This change is the last of a series of commits dedicated to have a
single DataLayout during compilation by using always the one owned
by the module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren

Differential Revision: http://reviews.llvm.org/D11103

(cherry picked from commit 5609fc56bca971e5a7efeaa6ca4676638eaec5ea)

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 243114
2015-07-24 16:04:22 +00:00
Mehdi Amini
5d8e569926 Revert "Remove access to the DataLayout in the TargetMachine"
This reverts commit 0f720d984f419c747709462f7476dff962c0bc41.

It breaks clang too badly, I need to prepare a proper patch for clang
first.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 243089
2015-07-24 03:36:55 +00:00
Mehdi Amini
b4bc424c9a Remove access to the DataLayout in the TargetMachine
Summary:
Replace getDataLayout() with a createDataLayout() method to make
explicit that it is intended to create a DataLayout only and not
accessing it for other purpose.

This change is the last of a series of commits dedicated to have a
single DataLayout during compilation by using always the one owned
by the module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren

Differential Revision: http://reviews.llvm.org/D11103

(cherry picked from commit 5609fc56bca971e5a7efeaa6ca4676638eaec5ea)

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 243083
2015-07-24 01:44:39 +00:00