Commit Graph

28 Commits

Author SHA1 Message Date
Teresa Johnson 388497e8be [ThinLTO] Handle an external call from an import to an alias in dest
The findExternalCalls routine ignores calls to functions already
defined in the dest module. This was not handling the case where
the definition in the current module is actually an alias to a
function call.

llvm-svn: 257493
2016-01-12 17:48:44 +00:00
Teresa Johnson 1b00f2d99a [ThinLTO] Use new in-place symbol changes for exporting module
Due to the new in-place ThinLTO symbol handling support added in
r257174, we now invoke renameModuleForThinLTO on the current
module from within the FunctionImport pass.

Additionally, renameModuleForThinLTO no longer needs to return the
Module as it is performing the renaming in place on the one provided.

This commit will be immediately preceeded by a companion clang patch to
remove its invocation of renameModuleForThinLTO.

llvm-svn: 257181
2016-01-08 17:06:29 +00:00
Teresa Johnson a1080ee6f0 [ThinLTO] Delay metadata materializtion in function importer
The function importer was still materializing metadata when modules were
loaded for function importing. We only want to materialize it when we
are going to invoke the metadata linking postpass. Materializing it
before function importing is not only unnecessary, but also causes
metadata referenced by imported functions to be mapped in early, and
then not connected to the rest of the module level metadata when it is
ultimately linked in.

Augmented the test case to specifically check for the metadata being
properly connected, which it wasn't before this fix.

llvm-svn: 257171
2016-01-08 14:17:41 +00:00
Benjamin Kramer fe2b541546 [FunctionImport] Move pass into anonymous namespace.
No functional change.

llvm-svn: 256374
2015-12-24 10:03:35 +00:00
Teresa Johnson e5a6191732 [ThinLTO] Metadata linking for imported functions
Summary:
Second patch split out from http://reviews.llvm.org/D14752.

Maps metadata as a post-pass from each module when importing complete,
suturing up final metadata to the temporary metadata left on the
imported instructions.

This entails saving the mapping from bitcode value id to temporary
metadata in the importing pass, and from bitcode value id to final
metadata during the metadata linking postpass.

Depends on D14825.

Reviewers: dexonsmith, joker.eph

Subscribers: davidxl, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D14838

llvm-svn: 255909
2015-12-17 17:14:09 +00:00
Rafael Espindola 434e956181 Change linkInModule to take a std::unique_ptr.
Passing in a std::unique_ptr should help find errors when the module
is used after being linked into another module.

llvm-svn: 255842
2015-12-16 23:16:33 +00:00
Rafael Espindola 19ed1951f6 A better attempt to add a missing include
llvm-svn: 255578
2015-12-14 23:34:35 +00:00
Rafael Espindola 42d04b4e29 Trying to fix the build in a bot.
llvm-svn: 255577
2015-12-14 23:31:08 +00:00
Rafael Espindola 9d2bfc4874 Use diagnostic handler in the LLVMContext
This patch converts code that has access to a LLVMContext to not take a
diagnostic handler.

This has a few advantages

* It is easier to use a consistent diagnostic handler in a single program.
* Less clutter since we are not passing a handler around.

It does make it a bit awkward to implement some C APIs that return a
diagnostic string. I will propose new versions of these APIs and
deprecate the current ones.

llvm-svn: 255571
2015-12-14 23:17:03 +00:00
Teresa Johnson 9f2ff9c669 [ThinLTO] Debug message cleanup (NFC)
Added some missing spaces between the module identifier and the start of
the debug message. Also added a ":" after the module identifier to make
this look a little nicer.

llvm-svn: 255259
2015-12-10 16:39:07 +00:00
Rafael Espindola 9edc3b8403 Don't assign a temporary string to a StringRef.
Should fix the windows debug and asan bots.

llvm-svn: 255149
2015-12-09 20:41:10 +00:00
Teresa Johnson 7f961e14d3 [ThinLTO] FunctionImport pass can take a const index pointer (NFC)
llvm-svn: 255140
2015-12-09 19:39:47 +00:00
Mehdi Amini 7e88d0da38 The current importing scheme is processing one function at a time,
loading the source Module, linking the function in the destination
module, and destroying the source Module before repeating with the
next function to import (potentially from the same Module).

Ideally we would keep the source Module alive and import the next
Function needed from this Module. Unfortunately this is not possible
because the linker does not leave it in a usable state.

However we can do better by first computing the list of all candidates
per Module, and only then load the source Module and import all the
function we need for it.

The trick to process callees is to materialize function in the source
module when building the list of function to import, and inspect them
in their source module, collecting the list of callees for each
callee.

When we move the the actual import, we will import from each source
module exactly once. Each source module is loaded exactly once.
The only drawback it that it requires to have all the lazy-loaded
source Module in memory at the same time.

Currently this patch already improves considerably the link time,
a multithreaded link of llvm-dis on my laptop was:

  real  1m12.175s  user  6m32.430s sys  0m10.529s

and is now:

  real  0m40.697s  user  2m10.237s sys  0m4.375s

Note: this is the full link time (linker+Import+Optimizer+CodeGen)

Differential Revision: http://reviews.llvm.org/D15178

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 255100
2015-12-09 08:17:35 +00:00
Mehdi Amini 5411d0510c Fix/Improve Debug print in FunctionImport pass
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 255071
2015-12-08 23:04:19 +00:00
Mehdi Amini d16c8065ff Remove caching in FunctionImport: a Module can't be reused after being linked from
The Linker destroys the source module (API change coming to make it explicit)

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 255064
2015-12-08 22:39:40 +00:00
Teresa Johnson 5fcbdb717c [ThinLTO] Support for specifying function index from pass manager
Summary:
Add a field on the PassManagerBuilder that clang or gold can use to pass
down a pointer to the function index in memory to use for importing when
the ThinLTO backend is triggered. Add support to supply this to the
function import pass.

Reviewers: joker.eph, dexonsmith

Subscribers: davidxl, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D15024

llvm-svn: 254926
2015-12-07 19:21:11 +00:00
Mehdi Amini 311fef6ea5 clang-format FunctionImport after refactoring (NFC)
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254585
2015-12-03 02:58:14 +00:00
Mehdi Amini c8c551701e Refactor FunctionImporter::importFunctions with a helper function to process the Worklist (NFC)
This precludes some more functional changes to perform bulk imports.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254583
2015-12-03 02:37:33 +00:00
Mehdi Amini ffe2e4aae0 Change ModuleLinker to take a set of GlobalValues to import instead of a single one
For efficiency reason, when importing multiple functions for the same Module,
we can avoid reparsing it every time.

Differential Revision: http://reviews.llvm.org/D15102

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254486
2015-12-02 04:34:28 +00:00
Mehdi Amini a11bdc8ef7 Modify FunctionImport to take a callback to load modules
When linking static archive, there is no individual module files to
load. Instead they can be mmap'ed and could be initialized from a
buffer directly. The callback provide flexibility to override the
scheme for loading module from the summary.

Differential Revision: http://reviews.llvm.org/D15101

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254479
2015-12-02 02:00:29 +00:00
Rafael Espindola 0e309fe860 Use references now that it is natural to do so.
The linker never takes ownership of a module or changes which module it
is refering to, making it natural to use references.

llvm-svn: 254449
2015-12-01 19:50:54 +00:00
Teresa Johnson 430110cc0b [ThinLTO] Wrap dbgs() output in DEBUG macro
Missed in a couple places.

llvm-svn: 254422
2015-12-01 17:12:10 +00:00
Teresa Johnson d582f5b3f8 [ThinLTO] Remove stale comment (NFC)
Stale as of r254036 which added basic profitability check.

llvm-svn: 254421
2015-12-01 16:45:23 +00:00
Teresa Johnson 3930361969 [ThinLTO] Add option to limit importing based on instruction count
Add a simple initial heuristic to control importing based on the number
of instructions recorded in the function's summary. Add option to
control the limit, and test using option.

llvm-svn: 254036
2015-11-24 22:55:46 +00:00
Teresa Johnson d450da3281 [ThinLTO] Refactor function body scan during importing into helper (NFC)
llvm-svn: 254020
2015-11-24 21:15:19 +00:00
Teresa Johnson 130de7af7f [ThinLTO] Enable iterative importing in FunctionImport pass
Analyze imported function bodies and add any new external calls to
the worklist for importing. Currently no controls on the importing
so this will end up importing everything possible in the call tree
below the importing module. Basic profitability checks coming next.

Update test to check for iteratively inlined functions.

llvm-svn: 254011
2015-11-24 19:55:04 +00:00
Teresa Johnson 17626654fd [ThinLTO] Fix FunctionImport alias checking and test
Skip imports for weak_any aliases as well. Fix the test to check
non-import of weak aliases and functions, and import of normal alias.

llvm-svn: 253991
2015-11-24 16:10:43 +00:00
Mehdi Amini 42418aba58 Add a FunctionImporter helper to perform summary-based cross-module function importing
Summary:
This is a helper to perform cross-module import for ThinLTO. Right now
it is importing naively every possible called functions.

Reviewers: tejohnson

Subscribers: dexonsmith, llvm-commits

Differential Revision: http://reviews.llvm.org/D14914

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 253954
2015-11-24 06:07:49 +00:00