Commit Graph

435 Commits

Author SHA1 Message Date
Bill Wendling
a351b16758 Merging r214519:
------------------------------------------------------------------------
r214519 | rafael | 2014-08-01 07:57:05 -0700 (Fri, 01 Aug 2014) | 3 lines

Remove lto_codegen_set_attr.

It was never exported, so no functionality change.
------------------------------------------------------------------------


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@214682 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-04 04:21:04 +00:00
Gerolf Hoflehner
d94715e273 MergedLoadStoreMotion pass
Merges equivalent loads on both sides of a hammock/diamond
and hoists into into the header.
Merges equivalent stores on both sides of a hammock/diamond
and sinks it to the footer.
Can enable if conversion and tolerate better load misses
and store operand latencies.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213396 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 19:13:09 +00:00
Hal Finkel
11af4b49b2 Add a dereferenceable attribute
This attribute indicates that the parameter or return pointer is
dereferenceable. Practically speaking, loads from such a pointer within the
associated byte range are safe to speculatively execute. Such pointer
parameters are common in source languages (C++ references, for example).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213385 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 15:51:28 +00:00
Chandler Carruth
39ea80cc56 Re-apply r211287: Remove support for LLVM runtime multi-threading.
I'll fix the problems in libclang and other projects in ways that don't
require <mutex> until we sort out the cygwin situation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211900 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-27 15:13:01 +00:00
NAKAMURA Takumi
cdde33ebaa Revert r211287, "Remove support for LLVM runtime multi-threading."
libclang still requires it on cygming, lack of incomplete <mutex>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211592 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-24 13:36:31 +00:00
Zachary Turner
a4d0ff9cd1 Remove support for LLVM runtime multi-threading.
After a number of previous small iterations, the functions
llvm_start_multithreaded() and llvm_stop_multithreaded() have
been reduced essentially to no-ops.  This change removes them
entirely.

Reviewed by: rnk, dblaikie

Differential Revision: http://reviews.llvm.org/D4216

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211287 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-19 18:18:23 +00:00
Zachary Turner
5ea46694d0 Revert r211066, 211067, 211068, 211069, 211070.
These were committed accidentally from the wrong branch before having
a review sign-off.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211072 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-16 22:49:41 +00:00
Zachary Turner
aedb5523d2 Remove some more code out into a separate CL.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211067 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-16 22:40:17 +00:00
Richard Smith
f8f75df346 [modules] The LLVM C API does not require C++!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210842 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-12 22:09:39 +00:00
Zachary Turner
63ce00b72f Revert "Remove support for runtime multi-threading."
This reverts revision r210600.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210603 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-10 23:15:43 +00:00
Zachary Turner
529e9d307e Remove support for runtime multi-threading.
This patch removes the functions llvm_start_multithreaded() and
llvm_stop_multithreaded(), and changes llvm_is_multithreaded()
to return a constant value based on the value of the compile-time
definition LLVM_ENABLE_THREADS.

Previously, it was possible to have compile-time support for
threads on, and runtime support for threads off, in which case
certain mutexes were not allocated or ever acquired.  Now, if the
build is created with threads enabled, mutexes are always acquired.

A test before/after patch of compiling a very large TU showed no
noticeable performance impact of this change.

Reviewers: rnk

Differential Revision: http://reviews.llvm.org/D4076

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210600 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-10 23:01:20 +00:00
Tom Roeder
5d0f7af3dc Add a new attribute called 'jumptable' that creates jump-instruction tables for functions marked with this attribute.
It includes a pass that rewrites all indirect calls to jumptable functions to pass through these tables.

This also adds backend support for generating the jump-instruction tables on ARM and X86.
Note that since the jumptable attribute creates a second function pointer for a
function, any function marked with jumptable must also be marked with unnamed_addr.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210280 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-05 19:29:43 +00:00
Richard Smith
651f680b79 [modules] Add module maps for LLVM. These are not quite ready for prime-time
yet, but only a few more Clang patches need to land. (I have 'ninja check'
passing locally.)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209269 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-21 02:46:14 +00:00
Nick Lewycky
fe47ebfad3 Add 'nonnull', a new parameter and return attribute which indicates that the pointer is not null. Instcombine will elide comparisons between these and null. Patch by Luqman Aden!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209185 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-20 01:23:40 +00:00
Juergen Ributzka
9bc1b73c9e Add C API for thread yielding callback.
Sometimes a LLVM compilation may take more time then a client would like to
wait for. The problem is that it is not possible to safely suspend the LLVM
thread from the outside. When the timing is bad it might be possible that the
LLVM thread holds a global mutex and this would block any progress in any other
thread.

This commit adds a new yield callback function that can be registered with a
context. LLVM will try to yield by calling this callback function, but there is
no guaranteed frequency. LLVM will only do so if it can guarantee that
suspending the thread won't block any forward progress in other LLVM contexts
in the same process.

Once the client receives the call back it can suspend the thread safely and
resume it at another time.

Related to <rdar://problem/16728690>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208945 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-16 02:33:15 +00:00
Juergen Ributzka
218bad2bc5 Revert "[PM] Add pass run listeners to the pass manager."
Revert the current implementation and C API. New implementation and C APIs are
in the works.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208904 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-15 17:49:20 +00:00
Rafael Espindola
834384bf5b Split GlobalValue into GlobalValue and GlobalObject.
This allows code to statically accept a Function or a GlobalVariable, but
not an alias. This is already a cleanup by itself IMHO, but the main
reason for it is that it gives a lot more confidence that the refactoring to fix
the design of GlobalAlias is correct. That will be a followup patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208716 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-13 18:45:48 +00:00
Rafael Espindola
dd326086fc Move LTOModule and LTOCodeGenerator to the llvm namespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207911 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-03 14:59:52 +00:00
Rafael Espindola
fcee7227d5 Style update: don't duplicate comments, they were getting out of sync.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207909 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-03 14:34:48 +00:00
Juergen Ributzka
4e0cc51d79 [PM] Add pass run listeners to the pass manager.
This commit provides the necessary C/C++ APIs and infastructure to enable fine-
grain progress report and safe suspension points after each pass in the pass
manager.

Clients can provide a callback function to the pass manager to call after each
pass. This can be used in a variety of ways (progress report, dumping of IR
between passes, safe suspension of threads, etc).

The run listener list is maintained in the LLVMContext, which allows a multi-
threaded client to be only informed for it's own thread. This of course assumes
that the client created a LLVMContext for each thread.

This fixes <rdar://problem/16728690>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207430 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-28 18:19:25 +00:00
Tom Roeder
817f5e2fa1 Add an -mattr option to the gold plugin to support subtarget features in LTO
This adds support for an -mattr option to the gold plugin and to llvm-lto. This
allows the caller to specify details of the subtarget architecture, like +aes,
or +ssse3 on x86.  Note that this requires a change to the include/llvm-c/lto.h
interface: it adds a function lto_codegen_set_attr and it increments the
version of the interface.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207279 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-25 21:46:51 +00:00
Rafael Espindola
7426771280 Convert getFileOffset to getOffset and move it to its only user.
We normally don't drop functions from the C API's, but in this case I think we
can:

* The old implementation of getFileOffset was fairly broken
* The introduction of LLVMGetSymbolFileOffset was itself a C api breaking
  change as it removed LLVMGetSymbolOffset.
* It is an incredibly specialized use case. The only reason MCJIT needs it is
  because of its odd position of being a dynamic linker of .o files.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206750 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-21 13:45:32 +00:00
Tom Stellard
57f45392e2 Added new functionality to LLVM C API to use DiagnosticInfo to handle errors
Patch by: Darren Powell

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206407 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-16 17:45:04 +00:00
James Molloy
555f97f2bc Teach llvm-lto to respect the given RelocModel.
Patch by Nick Tomlinson!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206177 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-14 13:54:16 +00:00
Richard Smith
0bd8ea3823 The LLVM C API shouldn't be including a file from the C++ API. Especially not a
file that it doesn't use.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205755 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-08 10:47:04 +00:00
Duncan P. N. Exon Smith
3845c071a7 Revert "Reapply "LTO: add API to set strategy for -internalize""
This reverts commit r199244.

Conflicts:
	include/llvm-c/lto.h
	include/llvm/LTO/LTOCodeGenerator.h
	lib/LTO/LTOCodeGenerator.cpp

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205471 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-02 22:05:57 +00:00
Tim Northover
7b837d8c75 ARM64: initial backend import
This adds a second implementation of the AArch64 architecture to LLVM,
accessible in parallel via the "arm64" triple. The plan over the
coming weeks & months is to merge the two into a single backend,
during which time thorough code review should naturally occur.

Everything will be easier with the target in-tree though, hence this
commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205090 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-29 10:18:08 +00:00
Tim Northover
b7dec2139c llvm-c: expose unnamedaddr field of globals
Patch by Manuel Jacob.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203482 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-10 19:24:35 +00:00
Chandler Carruth
7c00d18607 [Modules] Fix a layering issue that is actually impacting the modules
selfhost.

The 'Core.h' C-API header is part of the IR LLVM library. (One might
even argue it should be called IR.h, but that's a separate point.) We
can't include it into a Support header without violating the layering,
and in a way that breaks modules. MemoryBuffer's opaque C type was being
defined in the Core.h C-API header despite being in the Support library,
and thus we ended up with this weird issue.

It turns out that there were other constructs from the Support library
in the Core.h header. This patch lifts all of them into Support.h and
then includes that into Core.h.

The only possible fallout is if someone was including Support.h and
relying on Core.h to be visible for their own uses. Considering the
narrow interface actually provided by the C-API for the Support library,
this seems a very, very unlikely mistake.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203071 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-06 04:13:12 +00:00
Peter Zotov
8a25ef92fb [C API] Implement LLVM{Get,Set}Alignment for AllocaInst.
Patch by Manuel Jacob.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202936 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-05 05:05:34 +00:00
Reid Kleckner
1372b78679 C API: Add functions to get or set a GlobalValue's DLLStorageClass
Patch by Manuel Jacob!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202928 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-05 02:34:23 +00:00
Tobias Grosser
72c42d9341 Add 'remark' diagnostic type in LLVM
A 'remark' is information that is not an error or a warning, but rather some
additional information provided to the user. In contrast to a 'note' a 'remark'
is an independent diagnostic, whereas a 'note' always depends on another
diagnostic.

A typical use case for remark nodes is information provided to the user, e.g.
information provided by the vectorizer about loops that have been vectorized.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202474 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-28 09:08:45 +00:00
Manman Ren
f3fc8c9d09 LTO API: add lto_module_create_from_memory_with_path.
This function adds an extra path argument to lto_module_create_from_memory.
The path argument will be passed to makeBuffer to make sure the MemoryBuffer
has a name and the created module has a module identifier.

This is mainly for emitting warning messages from the linker. When we emit
warning message on a module, we can use the module identifier.

rdar://15985737


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201114 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-10 23:26:14 +00:00
Alp Toker
ae43cab6ba Fix known typos
Sweep the codebase for common typos. Includes some changes to visible function
names that were misspelt.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200018 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 17:20:08 +00:00
Juergen Ributzka
9ce88db752 Add target analysis passes to the codegen pipeline for MCJIT.
This patch adds the target analysis passes (usually TargetTransformInfo) to the
codgen pipeline. We also expose now the AddAnalysisPasses method through the C
API, because the optimizer passes would also benefit from better target-specific
cost models.

Reviewed by Andrew Kaylor

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199926 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-23 19:23:28 +00:00
Yunzhong Gao
a747cf1c4d Adding new LTO APIs to parse metadata nodes and extract linker options and
dependent libraries from a bitcode module.

Differential Revision: http://llvm-reviews.chandlerc.com/D2343



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199759 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-21 18:31:27 +00:00
Duncan P. N. Exon Smith
7c41150e85 LTO: document LTO_API_VERSION for each API
Adding a doxygen comment for each bit of API to indicate at which
LTO_API_VERSION each was available, manually gleaned from successive
git-blames.  A few notes:

- LTO_API_VERSION was set to 3 at its introduction.
- I've indicated all the API introduced before LTO_API_VERSION was
  around as available "prior to LTO_API_VERSION=3".
- A number of API changes neglected to bump LTO_API_VERSION.  These I've
  indicated as available at the *next* bump of LTO_API_VERSION.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199429 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-16 21:37:17 +00:00
Quentin Colombet
4c831d97bf [LTO] Add a hook to map LLVM diagnostics into the clients of LTO.
Add a hook in the C API of LTO so that clients of the code generator can set
their own handler for the LLVM diagnostics.
The handler is defined like this:
typedef void (*lto_diagnostic_handler_t)(lto_codegen_diagnostic_severity_t
severity, const char *diag, void *ctxt)
- severity says how bad this is.
- diag is a string that contains the diagnostic message.
- ctxt is the registered context for this handler.

This hook is more general than the lto_get_error_message, since this function
keeps only the latest message and can only be queried when something went wrong
(no warning for instance).

<rdar://problem/15517596>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199338 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-15 22:04:35 +00:00
Duncan P. N. Exon Smith
3e4542b2ca Reapply "LTO: add API to set strategy for -internalize"
Reapply r199191, reverted in r199197 because it carelessly broke
Other/link-opts.ll.  The problem was that calling
createInternalizePass("main") would select
createInternalizePass(bool("main")) instead of
createInternalizePass(ArrayRef<const char *>("main")).  This commit
fixes the bug.

The original commit message follows.

Add API to LTOCodeGenerator to specify a strategy for the -internalize
pass.

This is a new attempt at Bill's change in r185882, which he reverted in
r188029 due to problems with the gold linker.  This puts the onus on the
linker to decide whether (and what) to internalize.

In particular, running internalize before outputting an object file may
change a 'weak' symbol into an internal one, even though that symbol
could be needed by an external object file --- e.g., with arclite.

This patch enables three strategies:

- LTO_INTERNALIZE_FULL: the default (and the old behaviour).
- LTO_INTERNALIZE_NONE: skip -internalize.
- LTO_INTERNALIZE_HIDDEN: only -internalize symbols with hidden
  visibility.

LTO_INTERNALIZE_FULL should be used when linking an executable.

Outputting an object file (e.g., via ld -r) is more complicated, and
depends on whether hidden symbols should be internalized.  E.g., for
ld -r, LTO_INTERNALIZE_NONE can be used when -keep_private_externs, and
LTO_INTERNALIZE_HIDDEN can be used otherwise.  However,
LTO_INTERNALIZE_FULL is inappropriate, since the output object file will
eventually need to link with others.

lto_codegen_set_internalize_strategy() sets the strategy for subsequent
calls to lto_codegen_write_merged_modules() and lto_codegen_compile*().

<rdar://problem/14334895>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199244 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-14 18:52:17 +00:00
Nico Rieck
38f68c5a2e Decouple dllexport/dllimport from linkage
Representing dllexport/dllimport as distinct linkage types prevents using
these attributes on templates and inline functions.

Instead of introducing further mixed linkage types to include linkonce and
weak ODR, the old import/export linkage types are replaced with a new
separate visibility-like specifier:

  define available_externally dllimport void @f() {}
  @Var = dllexport global i32 1, align 4

Linkage for dllexported globals and functions is now equal to their linkage
without dllexport. Imported globals and functions must be either
declarations with external linkage, or definitions with
AvailableExternallyLinkage.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199218 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-14 15:22:47 +00:00
Nico Rieck
55463f4ec1 Revert "Decouple dllexport/dllimport from linkage"
Revert this for now until I fix an issue in Clang with it.

This reverts commit r199204.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199207 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-14 12:38:32 +00:00
Nico Rieck
bce07a0c3b Decouple dllexport/dllimport from linkage
Representing dllexport/dllimport as distinct linkage types prevents using
these attributes on templates and inline functions.

Instead of introducing further mixed linkage types to include linkonce and
weak ODR, the old import/export linkage types are replaced with a new
separate visibility-like specifier:

  define available_externally dllimport void @f() {}
  @Var = dllexport global i32 1, align 4

Linkage for dllexported globals and functions is now equal to their linkage
without dllexport. Imported globals and functions must be either
declarations with external linkage, or definitions with
AvailableExternallyLinkage.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199204 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-14 11:55:03 +00:00
NAKAMURA Takumi
d13b9da1b6 Revert r199191, "LTO: add API to set strategy for -internalize"
Please update also Other/link-opts.ll, in next time.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199197 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-14 09:40:18 +00:00
Duncan P. N. Exon Smith
67af0456bc LTO: add API to set strategy for -internalize
Add API to LTOCodeGenerator to specify a strategy for the -internalize
pass.

This is a new attempt at Bill's change in r185882, which he reverted in
r188029 due to problems with the gold linker.  This puts the onus on the
linker to decide whether (and what) to internalize.

In particular, running internalize before outputting an object file may
change a 'weak' symbol into an internal one, even though that symbol
could be needed by an external object file --- e.g., with arclite.

This patch enables three strategies:

- LTO_INTERNALIZE_FULL: the default (and the old behaviour).
- LTO_INTERNALIZE_NONE: skip -internalize.
- LTO_INTERNALIZE_HIDDEN: only -internalize symbols with hidden
  visibility.

LTO_INTERNALIZE_FULL should be used when linking an executable.

Outputting an object file (e.g., via ld -r) is more complicated, and
depends on whether hidden symbols should be internalized.  E.g., for
ld -r, LTO_INTERNALIZE_NONE can be used when -keep_private_externs, and
LTO_INTERNALIZE_HIDDEN can be used otherwise.  However,
LTO_INTERNALIZE_FULL is inappropriate, since the output object file will
eventually need to link with others.

lto_codegen_set_internalize_strategy() sets the strategy for subsequent
calls to lto_codegen_write_merged_modules() and lto_codegen_compile*().

<rdar://problem/14334895>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199191 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-14 06:37:26 +00:00
NAKAMURA Takumi
095f4c451c Whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198934 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-10 11:12:01 +00:00
Kevin Enderby
284c8bc4b0 For the 'C' disassembler API, add a new ReferenceType for the
SymbolLookUp() call back to return a demangled C++ name to
be used as a comment.

For example darwin's otool(1) program the uses the llvm
disassembler now can produce disassembly like:

callq   __ZNK4llvm6Target20createMCDisassemblerERKNS_15MCSubtargetInfoE ## llvm::Target::createMCDisassembler(llvm::MCSubtargetInfo const&) const

Also fix a bug in LLVMDisasmInstruction() that was not flushing
the raw_svector_ostream for the disassembled instruction string
before copying it to the output buffer that was causing truncation
of the output.

rdar://10173828


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198637 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-06 22:08:08 +00:00
Reid Kleckner
4b70bfc905 Begin adding docs and IR-level support for the inalloca attribute
The inalloca attribute is designed to support passing C++ objects by
value in the Microsoft C++ ABI.  It behaves the same as byval, except
that it always implies that the argument is in memory and that the bytes
are never copied.  This attribute allows the caller to take the address
of an outgoing argument's memory and execute arbitrary code to store
into it.

This patch adds basic IR support, docs, and verification.  It does not
attempt to implement any lowering or fix any possibly broken transforms.

When this patch lands, a complete description of this feature should
appear at http://llvm.org/docs/InAlloca.html .

Differential Revision: http://llvm-reviews.chandlerc.com/D2173

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197645 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-19 02:14:12 +00:00
Richard Sandiford
0f778794c8 Add a Scalarizer pass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195471 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-22 16:58:05 +00:00
Filip Pizlo
d54beffaa3 Expose the fence instruction via the C API.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195173 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-20 00:07:49 +00:00
Hal Finkel
bebe48dbfe Add a loop rerolling pass
This adds a loop rerolling pass: the opposite of (partial) loop unrolling. The
transformation aims to take loops like this:

for (int i = 0; i < 3200; i += 5) {
  a[i]     += alpha * b[i];
  a[i + 1] += alpha * b[i + 1];
  a[i + 2] += alpha * b[i + 2];
  a[i + 3] += alpha * b[i + 3];
  a[i + 4] += alpha * b[i + 4];
}

and turn them into this:

for (int i = 0; i < 3200; ++i) {
  a[i] += alpha * b[i];
}

and loops like this:

for (int i = 0; i < 500; ++i) {
  x[3*i] = foo(0);
  x[3*i+1] = foo(0);
  x[3*i+2] = foo(0);
}

and turn them into this:

for (int i = 0; i < 1500; ++i) {
  x[i] = foo(0);
}

There are two motivations for this transformation:

  1. Code-size reduction (especially relevant, obviously, when compiling for
code size).

  2. Providing greater choice to the loop vectorizer (and generic unroller) to
choose the unrolling factor (and a better ability to vectorize). The loop
vectorizer can take vector lengths and register pressure into account when
choosing an unrolling factor, for example, and a pre-unrolled loop limits that
choice. This is especially problematic if the manual unrolling was optimized
for a machine different from the current target.

The current implementation is limited to single basic-block loops only. The
rerolling recognition should work regardless of how the loop iterations are
intermixed within the loop body (subject to dependency and side-effect
constraints), but the significant restriction is that the order of the
instructions in each iteration must be identical. This seems sufficient to
capture all current use cases.

This pass is not currently enabled by default at any optimization level.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194939 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-16 23:59:05 +00:00