Commit Graph

2081 Commits

Author SHA1 Message Date
Adhemerval Zanella
7b449889e7 PowerPC: Fix eh_frame relocation for PIC
This patch fixes the PPC eh_frame definitions for the personality and 
frame unwinding for PIC objects. It makes PIC build correctly creates
relative relocations in the '.rela.eh_frame' segments and thus avoiding
a text relocation that generates a DT_TEXTREL segments in link phase.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171506 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-04 19:08:13 +00:00
NAKAMURA Takumi
1eae141f19 Compiler.h: Leave LLVM_BUILTIN_UNREACHABLE undefined if it is unavailable in host compiler.
Users of LLVM_BUILTIN_UNREACHABLE should be responsible in the case when LLVM_BUILTIN_UNREACHABLE is undefined.

Actually, (0, (p)) in LLVM_ASSUME_ALIGNED(p, a) caused thousands of warnings on g++-4.4. It was a motivation in this commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171455 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-03 03:30:22 +00:00
Michael J. Spencer
3922757824 Restrict __builtin_assume_aligned to gcc 4.7+
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171408 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 20:23:49 +00:00
Michael J. Spencer
c8b18df9a7 [Support][Endian] Add support for specifying the alignment and native unaligned types.
* Add support for specifying the alignment to use.
* Add the concept of native endianness. Used for unaligned native types.

The native alignment and read/write simplification is based on a patch by Richard Smith.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171406 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 20:14:11 +00:00
Argyrios Kyrtzidis
8da72f82be Don't #include stuff outside the include guards.
This defeats the include-guard optimization when parsing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171405 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 19:42:53 +00:00
Chandler Carruth
0b8c9a80f2 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 11:36:10 +00:00
Chandler Carruth
eda54e193e Make it explicit that the only entry points to the Program object are
through the static helper functions. This is already true throughout the
codebase.

Slowly, I'm going to re-implement these static helpers in terms of a new
process based interface which can expose more information, and remove
the program object entirely.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171335 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 23:44:49 +00:00
Chandler Carruth
a0d8f28a9c Remove an unused method on Program.
I'm simplifying this interface as much as I can before merging it with
the new process interface.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171334 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 23:44:47 +00:00
Chandler Carruth
2bbe466475 Remove an unused method on the Program class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171332 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 23:38:28 +00:00
Chandler Carruth
f5867ab717 Go ahead and get rid of the old page size interface and convert all the
users over to the new one. No sense maintaining this "compatibility"
layer it seems.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171331 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 23:31:56 +00:00
Chandler Carruth
814afe91cc Flesh out a page size accessor in the new API.
Implement the old API in terms of the new one. This simplifies the
implementation on Windows which can now re-use the self_process's once
initialization.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171330 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 23:23:35 +00:00
Chandler Carruth
02d75477cd Remove the declspecs from small alignments that we can force with
a union. These don't actually work for by-value function arguments, and
MSVC warns if they exist even while (we hope) it aligns the argument
correctly due to the other union member.

This means MSVC will miss out on optimizations based on the alignment of
the buffer, but really, there aren't that many for x86 and MSVC is
likely not doing a great job of optimizing LLVM and Clang anyways.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171328 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 22:18:01 +00:00
Chandler Carruth
e0e1985b3b Remove an unused function in the old Process interface.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171327 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 22:17:59 +00:00
Michael J. Spencer
3c6f89aa2e [AlignOf] Add AlignedCharArray and refactor AlignedCharArrayUnion.
This adds AlignedCharArray<Alignment, Size>. A templated struct that contains
a member named buffer of type char[Size] that is aligned to Alignment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171319 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 19:54:45 +00:00
Chandler Carruth
0184a841d3 Begin sketching out the process interface.
The coding style used here is not LLVM's style because this is modeled
after a Boost interface and thus done in the style of a candidate C++
standard library interface. I'll probably end up proposing it as
a standard C++ library if it proves to be reasonably portable and
useful.

This is just the most basic parts of the interface -- getting the
process ID out of it. However, it helps sketch out some of the boiler
plate such as the base class, derived class, shared code, and static
factory function. It also introduces a unittest so that I can
incrementally ensure this stuff works.

However, I've not even compiled this code for Windows yet. I'll try to
fix any Windows fallout from the bots, and if I can't fix it I'll revert
and get someone on Windows to help out. There isn't a lot more that is
mandatory, so soon I'll switch to just stubbing out the Windows side and
get Michael Spencer to help with implementation as he can test it
directly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171289 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 11:17:50 +00:00
Chandler Carruth
dac1eeb4b7 Start sketching out a roadmap for better subprocess management in the
LLVM libraries. Also, clean up the doxygen and formatting of the
existing interfaces.

With this change I'm calling the existing interface "legacy" because I'd
like to replace it with something much better. My end goal is to expose
a common set of interfaces for inspecting various properties of
a process, and implementations to expose those both for the current
process and for child processes. This will also expose more rich
interfaces for spawning and controling a subprocess, notably to use
system calls like wait3 and wait4 where available and gather detailed
resource usage stats about the subprocess.

My plan (discussed with Michael Spencer on IRC) is to base this loosely
around the proposed Boost.Process interface, but to implement
a relatively small subset of that functionality based around the needs
of LLVM, Clang, the Clang driver, etc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171285 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 09:29:16 +00:00
Bill Wendling
629fb82419 Change 'AttrVal' to 'AttrKind' to better reflect that it's a kind of attribute instead of the value of the attribute.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170972 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-22 00:37:52 +00:00
Richard Smith
9679a04da6 Fix some undefined behavior when parsing YAML input: don't try to compare an
uninitialized value against a default value. Found by -fsanitize=enum.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170970 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-22 00:31:54 +00:00
Roman Divacky
6af228a92a Remove MCTargetAsmLexer and its derived classes now that edis,
its only user, is gone.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170699 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 14:43:30 +00:00
Bill Wendling
034b94b170 Rename the 'Attributes' class to 'Attribute'. It's going to represent a single attribute in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170502 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-19 07:18:57 +00:00
Eric Christopher
6c583141bf Add support for passing -main-file-name all the way through to
the assembler.

Part of PR14624

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170390 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-18 00:31:01 +00:00
Nick Kledzik
fbc8a73e0c Use different trait techniques to be compatible with g++
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170355 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-17 19:02:05 +00:00
Bill Schmidt
b453e16855 This patch improves the 64-bit PowerPC InitialExec TLS support by providing
for a wider range of GOT entries that can hold thread-relative offsets.
This matches the behavior of GCC, which was not documented in the PPC64 TLS
ABI.  The ABI will be updated with the new code sequence.

Former sequence:

  ld 9,x@got@tprel(2)
  add 9,9,x@tls

New sequence:

  addis 9,2,x@got@tprel@ha
  ld 9,x@got@tprel@l(9)
  add 9,9,x@tls

Note that a linker optimization exists to transform the new sequence into
the shorter sequence when appropriate, by replacing the addis with a nop
and modifying the base register and relocation type of the ld.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170209 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-14 17:02:38 +00:00
Michael Ilseman
8ad435fa48 Pattern matching code for intrinsics.
Provides m_Argument that allows matching against a CallSite's specified argument. Provides m_Intrinsic pattern that can be templatized over the intrinsic id and bind/match arguments similarly to other pattern matchers. Implementations provided for 0 to 4 arguments, though it's very simple to extend for more. Also provides example template specialization for bswap (m_BSwap) and example of code cleanup for its use.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170091 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-13 03:13:36 +00:00
Michael Ilseman
8961924022 m_CombineOr and m_CombineAnd pattern combinators
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170086 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-13 02:55:53 +00:00
Benjamin Kramer
ae3ce26f99 YAMLIO: Remove all of the template instantiation hacks, I don't see why they're necessary and it breaks linking of the unit tests.
Also comes with a clang-format run on the cpp file, it had major style violations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170036 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 22:40:02 +00:00
Nick Kledzik
df2f74fa41 AlignedCharArrayUnion is erroring with non-clang compilers
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170031 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 22:03:57 +00:00
Nick Kledzik
8ceb8b764f Initial implementation of a utility for converting native data
structures to and from YAML using traits.  The first client will
be the test suite of lld.  The documentation will show up at:

   http://llvm.org/docs/YamlIO.html




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170019 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 20:46:15 +00:00
Bill Schmidt
349c2787cf This patch implements local-dynamic TLS model support for the 64-bit
PowerPC target.  This is the last of the four models, so we now have 
full TLS support.

This is mostly a straightforward extension of the general dynamic model.
I had to use an additional Chain operand to tie ADDIS_DTPREL_HA to the
register copy following ADDI_TLSLD_L; otherwise everything above the
ADDIS_DTPREL_HA appeared dead and was removed.

As before, there are new test cases to test the assembly generation, and
the relocations output during integrated assembly.  The expected code
gen sequence can be read in test/CodeGen/PowerPC/tls-ld.ll.

There are a couple of things I think can be done more efficiently in the
overall TLS code, so there will likely be a clean-up patch forthcoming;
but for now I want to be sure the functionality is in place.

Bill


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170003 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 19:29:35 +00:00
Michael Ilseman
1d4b150704 Pattern matchers for floating point values
m_ConstantFP - match and bind a float constant
m_SpecificConstantFP - match a specific floating point value or vector of floats of that value
m_FPOne - match a floating point 1.0 or vector of 1.0s
m_NegZero - match -0.0
m_AnyZero - match 0 or -0.0



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169939 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 00:23:43 +00:00
Michael Ilseman
08b25ce0a1 Remove FIXMEs surrounding Constant[Data]Vectors, instead
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169938 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 00:21:43 +00:00
Bill Schmidt
57ac1f458a This patch implements the general dynamic TLS model for 64-bit PowerPC.
Given a thread-local symbol x with global-dynamic access, the generated
code to obtain x's address is:

     Instruction                            Relocation            Symbol
  addis ra,r2,x@got@tlsgd@ha           R_PPC64_GOT_TLSGD16_HA       x
  addi  r3,ra,x@got@tlsgd@l            R_PPC64_GOT_TLSGD16_L        x
  bl __tls_get_addr(x@tlsgd)           R_PPC64_TLSGD                x
                                       R_PPC64_REL24           __tls_get_addr
  nop
  <use address in r3>

The implementation borrows from the medium code model work for introducing
special forms of ADDIS and ADDI into the DAG representation.  This is made
slightly more complicated by having to introduce a call to the external
function __tls_get_addr.  Using the full call machinery is overkill and,
more importantly, makes it difficult to add a special relocation.  So I've
introduced another opcode GET_TLS_ADDR to represent the function call, and
surrounded it with register copies to set up the parameter and return value.

Most of the code is pretty straightforward.  I ran into one peculiarity
when I introduced a new PPC opcode BL8_NOP_ELF_TLSGD, which is just like
BL8_NOP_ELF except that it takes another parameter to represent the symbol
("x" above) that requires a relocation on the call.  Something in the 
TblGen machinery causes BL8_NOP_ELF and BL8_NOP_ELF_TLSGD to be treated
identically during the emit phase, so this second operand was never
visited to generate relocations.  This is the reason for the slightly
messy workaround in PPCMCCodeEmitter.cpp:getDirectBrEncoding().

Two new tests are included to demonstrate correct external assembly and
correct generation of relocations using the integrated assembler.

Comments welcome!

Thanks,
Bill


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169910 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-11 20:30:11 +00:00
Bill Wendling
99faa3b4ec s/AttrListPtr/AttributeSet/g to better label what this class is going to be in the near future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169651 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-07 23:16:57 +00:00
Michael Ilseman
829c8bd98d Remove trailing whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169637 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-07 21:41:53 +00:00
Michael J. Spencer
717a142823 Updates to Win64EH.h structures.
Change member types of RuntimeFunction and UnwindInfo from uint64_t to
uint32_t:
These members represent addresses. According to MSDN, they are image
relative, that is, they are 32-bit offsets from the starting address
of the image that contains the function table entry.
See MSDN for more information:
RUNTIME_FUNCTION: http://msdn.microsoft.com/en-us/library/ft9x1kdx.aspx
UNWIND_INFO: http://msdn.microsoft.com/en-us/library/ddssxxy8.aspx

Make Win64.h platform-neutral:
The standard types unit8_t, uint16_t and uint32_t are replaced with
their counterparts from Endian.h. Accessor functions are introduced to
replace bit fields.

Patch by João Matos and Kai Nacke.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169414 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-05 20:12:13 +00:00
Bill Schmidt
d7802bf0dd This patch introduces initial-exec model support for thread-local storage
on 64-bit PowerPC ELF.

The patch includes code to handle external assembly and MC output with the
integrated assembler.  It intentionally does not support the "old" JIT.

For the initial-exec TLS model, the ABI requires the following to calculate
the address of external thread-local variable x:

 Code sequence            Relocation                  Symbol
  ld 9,x@got@tprel(2)      R_PPC64_GOT_TPREL16_DS      x
  add 9,9,x@tls            R_PPC64_TLS                 x

The register 9 is arbitrary here.  The linker will replace x@got@tprel
with the offset relative to the thread pointer to the generated GOT
entry for symbol x.  It will replace x@tls with the thread-pointer
register (13).

The two test cases verify correct assembly output and relocation output
as just described.

PowerPC-specific selection node variants are added for the two
instructions above:  LD_GOT_TPREL and ADD_TLS.  These are inserted
when an initial-exec global variable is encountered by
PPCTargetLowering::LowerGlobalTLSAddress(), and later lowered to
machine instructions LDgotTPREL and ADD8TLS.  LDgotTPREL is a pseudo
that uses the same LDrs support added for medium code model's LDtocL,
with a different relocation type.

The rest of the processing is straightforward.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169281 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-04 16:18:08 +00:00
Michael J. Spencer
6bc86018d1 [Support] Make FileOutputBuffer work on Windows.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169167 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-03 22:09:52 +00:00
Chandler Carruth
255f89faee Sort the #include lines for the include/... tree with the script.
AKA: Recompile *ALL* the source code!

This one went much better. No manual edits here. I spot-checked for
silliness and grep-checked for really broken edits and everything seemed
good. It all still compiles. Yell if you see something that looks goofy.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169133 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-03 17:02:12 +00:00
Chandler Carruth
4334dd96a9 Switch LLVM_USE_RVALUE_REFERENCES to LLVM_HAS_RVALUE_REFERENCES.
Rationale:
1) This was the name in the comment block. ;]
2) It matches Clang's __has_feature naming convention.
3) It matches other compiler-feature-test conventions.

Sorry for the noise. =]

I've also switch the comment block to use a \brief tag and not duplicate
the name.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168996 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-30 11:45:22 +00:00
Chandler Carruth
a5bf44b0b3 Separate out the tests for whether the compiler suports R-value
references from whether it supports an R-value reference *this. No
version of GCC today supports the latter, which breaks GCC C++11
compiles of LLVM and Clang now.

Also add doxygen comments clarifying what's going on here, and update
the usage in Optional. I'll update the usages in Clang next.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168993 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-30 11:04:18 +00:00
Chandler Carruth
84bcf93e0f Move the InstVisitor utility into VMCore where it belongs. It heavily
depends on the IR infrastructure, there is no sense in it being off in
Support land.

This is in preparation to start working to expand InstVisitor into more
special-purpose visitors that are still generic and can be re-used
across different passes. The expansion will go into the Analylis tree
though as nothing in VMCore needs it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168972 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-30 03:08:41 +00:00
Jordan Rose
adf0c3d82d Add a new C++11 compatibility macro, LLVM_LVALUE_FUNCTION.
This expands to '&', and is intended to be used when an /optional/ rvalue
override is available.

Before:
  void foo() const { ... }

After:
  void foo() const LLVM_LVALUE_FUNCTION { ... }
  void foo() && { ... }

This is used to allow moving the contents of an Optional.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168963 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-30 00:38:53 +00:00
Eli Bendersky
6b731486d4 Add backreference matching capabilities to Support/Regex, with
appropriate unit tests. This change in itself is not expected to
affect any functionality at this point, but it will serve as a
stepping stone to improve FileCheck's variable matching capabilities.

Luckily, our regex implementation already supports backreferences,
although a bit of hacking is required to enable it. It supports both
Basic Regular Expressions (BREs) and Extended Regular Expressions
(EREs), without supporting backrefs for EREs, following POSIX strictly
in this respect. And EREs is what we actually use (rightly). This is
contrary to many implementations (including the default on Linux) of
POSIX regexes, that do allow backrefs in EREs.

Adding backref support to our EREs is a very simple change in the
regcomp parsing code. I fail to think of significant cases where it
would clash with existing things, and can bring more versatility to
the regexes we write. There's always the danger of a backref in a
specially crafted regex causing exponential matching times, but since
we mainly use them for testing purposes I don't think it's a big
problem. [it can also be placed behind a flag specific to FileCheck,
if needed].

For more details, see:

* http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-November/055840.html
* http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20121126/156878.html



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168802 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-28 19:00:02 +00:00
Bill Schmidt
34a9d4b3b9 This patch implements medium code model support for 64-bit PowerPC.
The default for 64-bit PowerPC is small code model, in which TOC entries
must be addressable using a 16-bit offset from the TOC pointer.  Additionally,
only TOC entries are addressed via the TOC pointer.

With medium code model, TOC entries and data sections can all be addressed
via the TOC pointer using a 32-bit offset.  Cooperation with the linker
allows 16-bit offsets to be used when these are sufficient, reducing the
number of extra instructions that need to be executed.  Medium code model
also does not generate explicit TOC entries in ".section toc" for variables
that are wholly internal to the compilation unit.

Consider a load of an external 4-byte integer.  With small code model, the
compiler generates:

	ld 3, .LC1@toc(2)
	lwz 4, 0(3)

	.section	.toc,"aw",@progbits
.LC1:
	.tc ei[TC],ei

With medium model, it instead generates:

	addis 3, 2, .LC1@toc@ha
	ld 3, .LC1@toc@l(3)
	lwz 4, 0(3)

	.section	.toc,"aw",@progbits
.LC1:
	.tc ei[TC],ei

Here .LC1@toc@ha is a relocation requesting the upper 16 bits of the
32-bit offset of ei's TOC entry from the TOC base pointer.  Similarly,
.LC1@toc@l is a relocation requesting the lower 16 bits.  Note that if
the linker determines that ei's TOC entry is within a 16-bit offset of
the TOC base pointer, it will replace the "addis" with a "nop", and
replace the "ld" with the identical "ld" instruction from the small
code model example.

Consider next a load of a function-scope static integer.  For small code
model, the compiler generates:

	ld 3, .LC1@toc(2)
	lwz 4, 0(3)

	.section	.toc,"aw",@progbits
.LC1:
	.tc test_fn_static.si[TC],test_fn_static.si
	.type	test_fn_static.si,@object
	.local	test_fn_static.si
	.comm	test_fn_static.si,4,4

For medium code model, the compiler generates:

	addis 3, 2, test_fn_static.si@toc@ha
	addi 3, 3, test_fn_static.si@toc@l
	lwz 4, 0(3)

	.type	test_fn_static.si,@object
	.local	test_fn_static.si
	.comm	test_fn_static.si,4,4

Again, the linker may replace the "addis" with a "nop", calculating only
a 16-bit offset when this is sufficient.

Note that it would be more efficient for the compiler to generate:

	addis 3, 2, test_fn_static.si@toc@ha
        lwz 4, test_fn_static.si@toc@l(3)

The current patch does not perform this optimization yet.  This will be
addressed as a peephole optimization in a later patch.

For the moment, the default code model for 64-bit PowerPC will remain the
small code model.  We plan to eventually change the default to medium code
model, which matches current upstream GCC behavior.  Note that the different
code models are ABI-compatible, so code compiled with different models will
be linked and execute correctly.

I've tested the regression suite and the application/benchmark test suite in
two ways:  Once with the patch as submitted here, and once with additional
logic to force medium code model as the default.  The tests all compile
cleanly, with one exception.  The mandel-2 application test fails due to an
unrelated ABI compatibility with passing complex numbers.  It just so happens
that small code model was incredibly lucky, in that temporary values in 
floating-point registers held the expected values needed by the external
library routine that was called incorrectly.  My current thought is to correct
the ABI problems with _Complex before making medium code model the default,
to avoid introducing this "regression."

Here are a few comments on how the patch works, since the selection code
can be difficult to follow:

The existing logic for small code model defines three pseudo-instructions:
LDtoc for most uses, LDtocJTI for jump table addresses, and LDtocCPT for
constant pool addresses.  These are expanded by SelectCodeCommon().  The
pseudo-instruction approach doesn't work for medium code model, because
we need to generate two instructions when we match the same pattern.
Instead, new logic in PPCDAGToDAGISel::Select() intercepts the TOC_ENTRY
node for medium code model, and generates an ADDIStocHA followed by either
a LDtocL or an ADDItocL.  These new node types correspond naturally to
the sequences described above.

The addis/ld sequence is generated for the following cases:
 * Jump table addresses
 * Function addresses
 * External global variables
 * Tentative definitions of global variables (common linkage)

The addis/addi sequence is generated for the following cases:
 * Constant pool entries
 * File-scope static global variables
 * Function-scope static variables

Expanding to the two-instruction sequences at select time exposes the
instructions to subsequent optimization, particularly scheduling.

The rest of the processing occurs at assembly time, in
PPCAsmPrinter::EmitInstruction.  Each of the instructions is converted to
a "real" PowerPC instruction.  When a TOC entry needs to be created, this
is done here in the same manner as for the existing LDtoc, LDtocJTI, and
LDtocCPT pseudo-instructions (I factored out a new routine to handle this).

I had originally thought that if a TOC entry was needed for LDtocL or
ADDItocL, it would already have been generated for the previous ADDIStocHA.
However, at higher optimization levels, the ADDIStocHA may appear in a 
different block, which may be assembled textually following the block
containing the LDtocL or ADDItocL.  So it is necessary to include the
possibility of creating a new TOC entry for those two instructions.

Note that for LDtocL, we generate a new form of LD called LDrs.  This
allows specifying the @toc@l relocation for the offset field of the LD
instruction (i.e., the offset is replaced by a SymbolLo relocation).
When the peephole optimization described above is added, we will need
to do similar things for all immediate-form load and store operations.

The seven "mcm-n.ll" test cases are kept separate because otherwise the
intermingling of various TOC entries and so forth makes the tests fragile
and hard to understand.

The above assumes use of an external assembler.  For use of the
integrated assembler, new relocations are added and used by
PPCELFObjectWriter.  Testing is done with "mcm-obj.ll", which tests for
proper generation of the various relocations for the same sequences
tested with the external assembler.






git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168708 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 17:35:46 +00:00
Craig Topper
7279809d97 Add an extra slash so doxygen comments will be properly recognized.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168554 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-25 00:59:59 +00:00
Sean Silva
525398e137 Allow using MemoryBuffers with yaml::Stream directly.
The rationale is to get YAML filenames in diagnostics from
yaml::Stream::printError -- currently the filename is hard-coded as
"YAML" because there's no buffer information available.

Patch by Kim Gräsman!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168341 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-19 23:21:47 +00:00
Eric Christopher
5094c0c2de Add constant definitions for fission dwarf attributes, forms, etc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168218 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-16 23:04:31 +00:00
Dmitri Gribenko
79c07d2a36 Use empty parens for empty function parameter list instead of '(void)'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168049 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-15 16:51:49 +00:00
Ulrich Weigand
ba6086818d Add (some) PowerPC TLS relocation types to ELF.h and
generate them from PPCELFObjectWriter::getRelocTypeInner
as appropriate.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167864 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-13 19:24:36 +00:00
Duncan Sands
707276d415 Fix the instcombine GEP index widening transform to work correctly for vector
getelementptrs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167829 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-13 13:01:00 +00:00