Commit Graph

77 Commits

Author SHA1 Message Date
Victor Huang 652a8f150d [PowerPC][PCRelative] Thread Local Storage Support for Local Dynamic
This patch is the initial support for the Local Dynamic Thread Local Storage
model to produce code sequence and relocation correct to the ABI for the model
when using PC relative memory operations.

Differential Revision: https://reviews.llvm.org/D87721
2020-09-23 13:48:06 -05:00
Kamau Bridgeman c0f199e566 [PowerPC] Implement Thread Local Storage Support for Local Exec
This patch is the initial support for the Local Exec Thread Local
Storage model to produce code sequence and relocations correct
to the ABI for the model when using PC relative memory operations.

Patch by: Kamau Bridgeman

Differential Revision: https://reviews.llvm.org/D83404
2020-09-14 14:16:28 -05:00
Kamau Bridgeman 365f861c45 [PowerPC][PCRelative] Thread Local Storage Support for Initial Exec
This patch is the initial support for the Intial Exec Thread Local
Local Storage model to produce code sequence and relocations correct
to the ABI for the model when using PC relative memory operations.

Reviewed By: stefanp

Differential Revision: https://reviews.llvm.org/D81947
2020-08-21 10:13:11 -05:00
Kamau Bridgeman b74b80bb2d [PowerPC][PCRelative] Thread Local Storage Support for General Dynamic
This patch is the initial support for the General Dynamic Thread Local
Local Storage model to produce code sequence and relocations correct
to the ABI for the model when using PC relative memory operations.

Patch by: NeHuang

Reviewed By: stefanp

Differential Revision: https://reviews.llvm.org/D82315
2020-08-20 15:08:13 -05:00
Stefan Pintilie a60251d739 [PowerPC] Add linker opt for PC Relative GOT indirect accesses
A linker optimization is available on PowerPC for GOT indirect PCRelative loads.

The idea is that we can mark a usual GOT indirect load:

pld 3, vec@got@pcrel(0), 1
lwa 3, 4(3)

With a relocation to say that if we don't need to go through the GOT we can let
the linker further optimize this and replace a load with a nop.

  pld 3, vec@got@pcrel(0), 1
.Lpcrel1:
.reloc .Lpcrel1-8,R_PPC64_PCREL_OPT,.-(.Lpcrel1-8)
  lwa 3, 4(3)

This patch adds the logic that allows the compiler to add the R_PPC64_PCREL_OPT.

Reviewers: nemanjai, lei, hfinkel, sfertile, efriedma, tstellar, grosbach

Reviewed By: nemanjai

Differential Revision: https://reviews.llvm.org/D79864
2020-07-22 09:08:23 -05:00
Stefan Pintilie 1354a03e74 [PowerPC][Future] Implement PC Relative Tail Calls
Tail Calls were initially disabled for PC Relative code because it was not safe
to make certain assumptions about the tail calls (namely that all compiled
functions no longer used the TOC pointer in R2). However, once all of the
TOC pointer references have been removed it is safe to tail call everything
that was tail called prior to the PC relative additions as well as a number of
new cases.
For example, it is now possible to tail call indirect functions as there is no
need to save and restore the TOC pointer for indirect functions if the caller
is marked as may clobber R2 (st_other=1). For the same reason it is now also
possible to tail call functions that are external.

Differential Revision: https://reviews.llvm.org/D77788
2020-04-27 12:55:08 -05:00
Stefan Pintilie b771c4a842 [PowerPC][Future] More support for PCRel addressing for global values
Add initial support for PC Relative addressing for global values that
require GOT indirect addressing. This patch adds PCRelative support for
global addresses that may not be known at link time and may require
access through the GOT.

Differential Revision: https://reviews.llvm.org/D76064
2020-04-17 11:06:13 -05:00
Kang Zhang 513976df2e [PowerPC] Ignore implicit register operands for MCInst
Summary:
When doing the conversion: MachineInst -> MCInst, we should ignore the
implicit operands, it will expose more opportunity for InstiAlias.

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D77118
2020-04-16 16:22:43 +00:00
Stefan Pintilie 75828ef615 [PowerPC][Future] Initial support for PCRel addressing for constant pool loads
Add initial support for PC Relative addressing for constant pool loads.
This includes adding a new relocation for @pcrel and adding a new PowerPC flag
to identify PC relative addressing.

Differential Revision: https://reviews.llvm.org/D74486
2020-04-09 11:17:23 -05:00
Stefan Pintilie 6c4b40def7 [PowerPC][Future] Add Support For Functions That Do Not Use A TOC.
On PowerPC most functions require a valid TOC pointer.

This is the case because either the function itself needs to use this
pointer to access the TOC or because other functions that are called
from that function expect a valid TOC pointer in the register R2.
The main exception to this is leaf functions that do not access the TOC
since they are guaranteed not to need a valid TOC pointer.

This patch introduces a feature that will allow more functions to not
require a valid TOC pointer in R2.

Differential Revision: https://reviews.llvm.org/D73664
2020-04-08 08:07:35 -05:00
Fangrui Song 253379a56f [PowerPC] Delete IsDarwin from AsmPrinter functions 2020-01-24 00:22:24 -08:00
Fangrui Song a50567a31c [PowerPC][MC] Delete PPCMCExpr::IsDarwin 2020-01-23 22:30:08 -08:00
Fangrui Song 8e1f0974c2 [PowerPC] Delete PPCSubtarget::isDarwin and isDarwinABI
http://lists.llvm.org/pipermail/llvm-dev/2018-August/125614.html developers have agreed to remove Darwin support from POWER backends.

Reviewed By: sfertile

Differential Revision: https://reviews.llvm.org/D72067
2020-01-21 09:54:44 -08:00
Xiangling Liao ee68f1ec67 [NFC] Replace 'isDarwin' with 'IsDarwin'
Summary: Replace 'isDarwin' with 'IsDarwin' based on LLVM naming convention.

Differential Revision: https://reviews.llvm.org/D68336

llvm-svn: 373852
2019-10-06 14:44:22 +00:00
Sean Fertile 9df6177d38 [PowerPC][AIX]Add lowering of MCSymbol MachineOperand.
Adds machine operand lowering for MCSymbolSDNodes to the PowerPC
backend. This is needed to produce call instructions in assembly for AIX
because the callee operand is a MCSymbolSDNode. The test is XFAIL'ed for
asserts due to a (valid) assertion in PEI that the AIX ABI isn't supported yet.

Differential Revision: https://reviews.llvm.org/D63738

llvm-svn: 367133
2019-07-26 17:25:27 +00:00
Fangrui Song 96a192ea53 [PPC32] Support PLT calls for -msecure-plt -fpic
Summary:
In Secure PLT ABI, -fpic is similar to -fPIC. The differences are that:

* -fpic stores the address of _GLOBAL_OFFSET_TABLE_ in r30, while -fPIC stores .got2+0x8000.
* -fpic uses an addend of 0 for R_PPC_PLTREL24, while -fPIC uses 0x8000.

Reviewers: hfinkel, jhibbits, joerg, nemanjai, spetrovic

Reviewed By: jhibbits

Subscribers: adalava, kbarton, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63563

llvm-svn: 364324
2019-06-25 15:56:32 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +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
Strahinja Petrovic 06cf6a6490 [PowerPC] Secure PLT support
This patch supports secure PLT mode for PowerPC 32 architecture.

Differential Revision: https://reviews.llvm.org/D42112

llvm-svn: 328617
2018-03-27 11:23:53 +00:00
David Blaikie 6054e650ff Move TargetLoweringObjectFile from CodeGen to Target to fix layering
It's implemented in Target & include from other Target headers, so the
header should be in Target.

llvm-svn: 328392
2018-03-23 23:58:19 +00:00
David Blaikie b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
Tim Shen cee7536188 [XRay] support conditional return on PPC.
Summary: Conditional returns were not taken into consideration at all. Implement them by turning them into jumps and normal returns. This means there is a slightly higher performance penalty for conditional returns, but this is the best we can do, and it still disturbs little of the rest.

Reviewers: dberris, echristo

Subscribers: sanjoy, nemanjai, hiraditya, kbarton, llvm-commits

Differential Revision: https://reviews.llvm.org/D38102

llvm-svn: 314005
2017-09-22 18:30:02 +00:00
Chandler Carruth 6bda14b313 Sort the remaining #include lines in include/... and lib/....
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.

I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.

This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.

Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).

llvm-svn: 304787
2017-06-06 11:49:48 +00:00
Matthias Braun 8c209aa877 Cleanup dump() functions.
We had various variants of defining dump() functions in LLVM. Normalize
them (this should just consistently implement the things discussed in
http://lists.llvm.org/pipermail/cfe-dev/2014-January/034323.html

For reference:
- Public headers should just declare the dump() method but not use
  LLVM_DUMP_METHOD or #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
- The definition of a dump method should look like this:
  #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
  LLVM_DUMP_METHOD void MyClass::dump() {
    // print stuff to dbgs()...
  }
  #endif

llvm-svn: 293359
2017-01-28 02:02:38 +00:00
Eric Christopher dd7d68da58 Fix a hidden use of grabbing the Mangler from the AsmPrinter and update
accordingly.

llvm-svn: 281748
2016-09-16 17:07:13 +00:00
Rafael Espindola a99ccfce1a Drop support for creating $stubs.
They are created by ld64 since OS X 10.5.

llvm-svn: 274130
2016-06-29 14:59:50 +00:00
Rafael Espindola 8571aa3d5d Simplify handling of hidden stubs on PowerPC.
We now handle them just like non hidden ones. This was already the case
on x86 (r207518) and arm (r207517).

llvm-svn: 270205
2016-05-20 12:00:52 +00:00
Mehdi Amini bd7287ebe5 Move most user of TargetMachine::getDataLayout to the Module one
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

This patch is quite boring overall, except for some uglyness in
ASMPrinter which has a getDataLayout function but has some clients
that use it without a Module (llmv-dsymutil, llvm-dwarfdump), so
some methods are taking a DataLayout as parameter.

Reviewers: echristo

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

Differential Revision: http://reviews.llvm.org/D11090

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 242386
2015-07-16 06:11:10 +00:00
Rafael Espindola c233f74e6e Simplify the Mangler interface now that DataLayout is mandatory.
We only need to pass in a DataLayout when mangling a raw string, not when
constructing the mangler.

llvm-svn: 240405
2015-06-23 13:59:29 +00:00
Daniel Sanders c81f450f1a Clean up redundant copies of Triple objects. NFC
Summary:

Reviewers: rengolin

Reviewed By: rengolin

Subscribers: llvm-commits, rengolin, jholewinski

Differential Revision: http://reviews.llvm.org/D10382

llvm-svn: 239823
2015-06-16 15:44:21 +00:00
Jim Grosbach 13760bd152 MC: Clean up MCExpr naming. NFC.
llvm-svn: 238634
2015-05-30 01:25:56 +00:00
Jim Grosbach 6f482000e9 MC: Clean up method names in MCContext.
The naming was a mish-mash of old and new style. Update to be consistent
with the new. NFC.

llvm-svn: 237594
2015-05-18 18:43:14 +00:00
Jim Grosbach e9119e41ef MC: Modernize MCOperand API naming. NFC.
MCOperand::Create*() methods renamed to MCOperand::create*().

llvm-svn: 237275
2015-05-13 18:37:00 +00:00
Yaron Keren 75e0c4b060 Remove superfluous .str() and replace std::string concatenation with Twine.
llvm-svn: 233392
2015-03-27 17:51:30 +00:00
Samuel Antao 0d59f31d12 Add assertion to detect invalid registers in the PowerPC MC instruction lowering.
We have observed that noreg was being generated due to a bug in FastIsel and was not being detected during emission. It happens that in the Asm emission there is an assertion that detects this in getRegisterName() from the tbl-generated file PPCGenAsmWriter.inc. However, when emitting an Obj file, invalid registers can be emitted given that no check are made in getBinaryCodeFromInstr() from PPCGenMCCodeEmitter.inc. In order to cover all cases this adds an assertion for reg operands in LowerPPCMachineInstrToMCInst.

llvm-svn: 232525
2015-03-17 19:31:19 +00:00
Bill Schmidt 82f1c775a0 [PowerPC] Fix reverted patch r227976 to avoid register assignment issues
See full discussion in http://reviews.llvm.org/D7491.

We now hide the add-immediate and call instructions together in a
separate pseudo-op, which is tagged to define GPR3 and clobber the
call-killed registers.  The PPCTLSDynamicCall pass prior to RA now
expands this op into the two separate addi and call ops, with explicit
definitions of GPR3 on both instructions, and explicit clobbers on the
call instruction.  The pass is now marked as requiring and preserving
the LiveIntervals and SlotIndexes analyses, and fixes these up after
the replacement sequences are introduced.

Self-hosting has been verified on LE P8 and BE P7 with various
optimization levels, etc.  It has also been verified with the
--no-tls-optimize flag workaround removed.

llvm-svn: 228725
2015-02-10 19:09:05 +00:00
Hal Finkel 0d2a1515d5 Revert "r227976 - [PowerPC] Yet another approach to __tls_get_addr" and related fixups
Unfortunately, even with the workaround of disabling the linker TLS
optimizations in Clang restored (which has already been done), this still
breaks self-hosting on my P7 machine (-O3 -DNDEBUG -mcpu=native).

Bill is currently working on an alternate implementation to address the TLS
issue in a way that also fully elides the linker bug (which, unfortunately,
this approach did not fully), so I'm reverting this now.

llvm-svn: 228460
2015-02-06 23:07:40 +00:00
Bill Schmidt 685aa8b0c5 [PowerPC] Yet another approach to __tls_get_addr
This patch is a third attempt to properly handle the local-dynamic and
global-dynamic TLS models.

In my original implementation, calls to __tls_get_addr were hidden
from view until the asm-printer phase, at which point the underlying
branch-and-link instruction was created with proper relocations.  This
mostly worked well, but I used some repellent techniques to ensure
that the TLS_GET_ADDR nodes at the SD and MI levels correctly received
input from GPR3 and produced output into GPR3.  This proved to work
badly in the presence of multiple TLS variable accesses, with the
copies to and from GPR3 being scheduled incorrectly and generally
creating havoc.

In r221703, I addressed that problem by representing the calls to
__tls_get_addr as true calls during instruction lowering.  This had
the advantage of removing all of the bad hacks and relying on the
existing call machinery to properly glue the copies in place. It
looked like this was going to be the right way to go.

However, as a side effect of the recent discovery of problems with
linker optimizations for TLS, we discovered cases of suboptimal code
generation with this strategy.  The problem comes when tls_get_addr is
called for the same address, and there is a resulting CSE
opportunity.  It turns out that in such cases MachineCSE will common
the addis/addi instructions that set up the input value to
tls_get_addr, but will not common the calls themselves.  MachineCSE
does not have any machinery to common idempotent calls.  This is
perfectly sensible, since presumably this would be done at the IR
level, and introducing calls in the back end isn't commonplace.  In
any case, we end up with two calls to __tls_get_addr when one would
suffice, and that isn't good.

I presumed that the original design would have allowed commoning of
the machine-specific nodes that hid the __tls_get_addr calls, so as
suggested by Ulrich Weigand, I went back to that design and cleaned it
up so that the copies were properly held together by glue
nodes.  However, it turned out that this didn't work either...the
presence of copies to physical registers kept the machine-specific
nodes from being commoned also.

All of which leads to the design presented here.  This is a return to
the original design, except that no attempt is made to introduce
copies to and from GPR3 during instruction lowering.  Virtual registers
are used until prior to register allocation.  At that point, a special
pass is run that identifies the machine-specific nodes that hide the
tls_get_addr calls and introduces the copies to and from GPR3 around
them.  The register allocator then coalesces these copies away.  With
this design, MachineCSE succeeds in commoning tls_get_addr calls where
possible, and we get nice optimal code generation (better than GCC at
the moment, which does not common these calls).

One additional problem must be dealt with:  After introducing the
mentions of the physical register GPR3, the aggressive anti-dependence
breaker sees opportunities to improve scheduling by selecting a
different register instead.  Flags must be used on the instruction
descriptions to tell the anti-dependence breaker to keep its hands in
its pockets.

One thing missing from the original design was recording a definition
of the link register on the GET_TLS_ADDR nodes.  Doing this was found
to be insufficient to force a stack frame to be created, which led to
looping behavior because two different LR values were stored at the
same address.  This appears to have been an oversight in
PPCFrameLowering::determineFrameLayout(), which is repaired here.

Because MustSaveLR() returns true for calls to builtin_return_address,
this changed the expected behavior of
test/CodeGen/PowerPC/retaddr2.ll, which now stacks a frame but
formerly did not.  I've fixed the test case to reflect this.

There are existing TLS tests to catch regressions; the checks in
test/CodeGen/PowerPC/tls-store2.ll proved to be too restrictive in the
face of instruction scheduling with these changes, so I fixed that
up.

I've added a new test case based on the PrettyStackTrace module that
demonstrated the original problem. This checks that we get correct
code generation and that CSE of the calls to __get_tls_addr has taken
place.

llvm-svn: 227976
2015-02-03 16:16:01 +00:00
Eric Christopher 8b7706517c Move DataLayout back to the TargetMachine from TargetSubtargetInfo
derived classes.

Since global data alignment, layout, and mangling is often based on the
DataLayout, move it to the TargetMachine. This ensures that global
data is going to be layed out and mangled consistently if the subtarget
changes on a per function basis. Prior to this all targets(*) have
had subtarget dependent code moved out and onto the TargetMachine.

*One target hasn't been migrated as part of this change: R600. The
R600 port has, as a subtarget feature, the size of pointers and
this affects global data layout. I've currently hacked in a FIXME
to enable progress, but the port needs to be updated to either pass
the 64-bitness to the TargetMachine, or fix the DataLayout to
avoid subtarget dependent features.

llvm-svn: 227113
2015-01-26 19:03:15 +00:00
Chandler Carruth d9903888d9 [cleanup] Re-sort all the #include lines in LLVM using
utils/sort_includes.py.

I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.

llvm-svn: 225974
2015-01-14 11:23:27 +00:00
Bill Schmidt 3d9674cfb1 [PowerPC] Replace foul hackery with real calls to __tls_get_addr
My original support for the general dynamic and local dynamic TLS
models contained some fairly obtuse hacks to generate calls to
__tls_get_addr when lowering a TargetGlobalAddress.  Rather than
generating real calls, special GET_TLS_ADDR nodes were used to wrap
the calls and only reveal them at assembly time.  I attempted to
provide correct parameter and return values by chaining CopyToReg and
CopyFromReg nodes onto the GET_TLS_ADDR nodes, but this was also not
fully correct.  Problems were seen with two back-to-back stores to TLS
variables, where the call sequences ended up overlapping with unhappy
results.  Additionally, since these weren't real calls, the proper
register side effects of a call were not recorded, so clobbered values
were kept live across the calls.

The proper thing to do is to lower these into calls in the first
place.  This is relatively straightforward; see the changes to
PPCTargetLowering::LowerGlobalTLSAddress() in PPCISelLowering.cpp.
The changes here are standard call lowering, except that we need to
track the fact that these calls will require a relocation.  This is
done by adding a machine operand flag of MO_TLSLD or MO_TLSGD to the
TargetGlobalAddress operand that appears earlier in the sequence.

The calls to LowerCallTo() eventually find their way to
LowerCall_64SVR4() or LowerCall_32SVR4(), which call FinishCall(),
which calls PrepareCall().  In PrepareCall(), we detect the calls to
__tls_get_addr and immediately snag the TargetGlobalTLSAddress with
the annotated relocation information.  This becomes an extra operand
on the call following the callee, which is expected for nodes of type
tlscall.  We change the call opcode to CALL_TLS for this case.  Back
in FinishCall(), we change it again to CALL_NOP_TLS for 64-bit only,
since we require a TOC-restore nop following the call for the 64-bit
ABIs.

During selection, patterns in PPCInstrInfo.td and PPCInstr64Bit.td
convert the CALL_TLS nodes into BL_TLS nodes, and convert the
CALL_NOP_TLS nodes into BL8_NOP_TLS nodes.  This replaces the code
removed from PPCAsmPrinter.cpp, as the BL_TLS or BL8_NOP_TLS
nodes can now be emitted normally using their patterns and the
associated printTLSCall print method.

Finally, as a result of these changes, all references to get-tls-addr
in its various guises are no longer used, so they have been removed.

There are existing TLS tests to verify the changes haven't messed
anything up).  I've added one new test that verifies that the problem
with the original code has been fixed.

llvm-svn: 221703
2014-11-11 20:44:09 +00:00
Eric Christopher da84e33791 Use the triple to figure out if this is a darwin target, not
the subtarget.

llvm-svn: 219673
2014-10-14 08:25:26 +00:00
Eric Christopher d913448b38 Remove the TargetMachine forwards for TargetSubtargetInfo based
information and update all callers. No functional change.

llvm-svn: 214781
2014-08-04 21:25:23 +00:00
Hal Finkel 3ee2af7d1c [PowerPC] 32-bit ELF PIC support
This adds initial support for PPC32 ELF PIC (Position Independent Code; the
-fPIC variety), thus rectifying a long-standing deficiency in the PowerPC
backend.

Patch by Justin Hibbits!

llvm-svn: 213427
2014-07-18 23:29:49 +00:00
Craig Topper 062a2baef0 [C++] Use 'nullptr'. Target edition.
llvm-svn: 207197
2014-04-25 05:30:21 +00:00
Rafael Espindola a3ad4e693c move getNameWithPrefix and getSymbol to TargetMachine.
TargetLoweringBase is implemented in CodeGen, so before this patch we had
a dependency fom Target to CodeGen. This would show up as a link failure of
llvm-stress when building with -DBUILD_SHARED_LIBS=ON.

This fixes pr18900.

llvm-svn: 201711
2014-02-19 20:30:41 +00:00
Rafael Espindola daeafb4c2a Add back r201608, r201622, r201624 and r201625
r201608 made llvm corretly handle private globals with MachO. r201622 fixed
a bug in it and r201624 and r201625 were changes for using private linkage,
assuming that llvm would do the right thing.

They all got reverted because r201608 introduced a crash in LTO. This patch
includes a fix for that. The issue was that TargetLoweringObjectFile now has
to be initialized before we can mangle names of private globals. This is
trivially true during the normal codegen pipeline (the asm printer does it),
but LTO has to do it manually.

llvm-svn: 201700
2014-02-19 17:23:20 +00:00
Daniel Jasper 7e198ad862 Revert r201622 and r201608.
This causes the LLVMgold plugin to segfault. More information on the
replies to r201608.

llvm-svn: 201669
2014-02-19 12:26:01 +00:00
Rafael Espindola 09dcc6a536 Fix PR18743.
The IR
@foo = private constant i32 42

is valid, but before this patch we would produce an invalid MachO from it. It
was invalid because it would use an L label in a section where the liker needs
the labels in order to atomize it.

One way of fixing it would be to just reject this IR in the backend, but that
would not be very front end friendly.

What this patch does is use an 'l' prefix in sections that we know the linker
requires symbols for atomizing them. This allows frontends to just use
private and not worry about which sections they go to or how the linker handles
them.

One small issue with this strategy is that now a symbol name depends on the
section, which is not available before codegen. This is not a problem in
practice. The reason is that it only happens with private linkage, which will
be ignored by the non codegen users (llvm-nm and llvm-ar).

llvm-svn: 201608
2014-02-18 22:24:57 +00:00
Rafael Espindola 894843cb4e Move the llvm mangler to lib/IR.
This makes it available to tools that don't link with target (like llvm-ar).

llvm-svn: 198708
2014-01-07 21:19:40 +00:00