This API is proposed by Nick Kledzik. The semantic is:
--------------------------------------------------------------------------
Generate code for merged module into an array of native object files. On
success returns a pointer to an array of NativeObjectFile. The count
parameter returns the number of elements in the array. Each element is
a pointer/length for a generated mach-o/ELF buffer. The buffer is owned
by the lto_code_gen_t and will be freed when lto_codegen_dispose() is called,
or lto_codegen_compile() is called again. On failure, returns NULL
(check lto_get_error_message() for details).
extern const struct NativeObjectFile*
lto_codegen_compile_parallel(lto_code_gen_t cg, size_t *count);
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This API is currently only called on OSX platform. Linux or other Unixes
using GNU gold are not supposed to call this function, because on these systems,
object files are fed back to linker via disk file instead of memory buffer.
In this commit, lto_codegen_compile_parallel() simply calls
lto_codegen_compile() to return a single object file. In the near future,
this function is the entry point for compilation with partition. Linker can
blindly call this function even if partition is turned off; in this case,
compiler will return only one object file.
llvm-svn: 189297
In order to appease people (in Apple) who accuse me for committing "huge change" (?) without proper review.
Thank Eric for fixing a compile-warning.
llvm-svn: 188204
1. Add some helper classes for partitions. They are designed in a
way such that the top-level LTO driver will not see much difference
with or without partitioning.
2. Introduce work-dir. Now all intermediate files generated during
LTO phases will be saved under work-dir. User can specify the workdir
via -lto-workdir=/path/to/dir. By default the work-dir will be
erased before linker exit. To keep the workdir, do -lto-keep, or -lto-keep=1.
TODO: Erase the workdir, if the linker exit prematurely.
We are currently not able to remove directory on signal. The support
routines simply ignore directory.
3. Add one new API lto_codegen_get_files_need_remove().
Linker and LTO plugin will communicate via this API about which files
(including directories) need to removed before linker exit.
llvm-svn: 188188
Currently, when an invalid attribute is encountered on processing a .s file,
clang will abort due to llvm_unreachable. Invalid user input should not cause
an abnormal termination of the compiler. Change the interface to return a
boolean to indicate the failure as a first step towards improving hanlding of
malformed user input to clang.
Signed-off-by: Saleem Abdulrasool <compnerd@compnerd.org>
llvm-svn: 188047
Function attributes are the future! So just query whether we want to realign the
stack directly from the function instead of through a random target options
structure.
llvm-svn: 187618
Merge consecutive if-regions if they contain identical statements.
Both transformations reduce number of branches. The transformation
is guarded by a target-hook, and is currently enabled only for +R600,
but the correctness has been tested on X86 target using a variety of
CPU benchmarks.
Patch by: Mei Ye
llvm-svn: 187278
There's no need to specify a flag to omit frame pointer elimination on non-leaf
nodes...(Honestly, I can't parse that option out.) Use the function attribute
stuff instead.
llvm-svn: 187093
The main observation is that we never need both the filesize and the map size.
When mapping a slice of a file, it doesn't make sense to request a null
terminator and that would be the only case where the filesize would be used.
There are other cleanups that should be done in this area:
* A client should not have to pass the size (even an explicit -1) to say if
it wants a null terminator or not, so we should probably swap the argument
order.
* The default should be to not require a null terminator. Very few clients
require this, but many end up asking for it just because it is the default.
llvm-svn: 186984
Use the function attributes to pass along the stack protector buffer size.
Now that we have robust function attributes, don't use a command line option to
specify the stack protecto buffer size.
llvm-svn: 186863
There already have two "dead" functions, initialize{IPO|IPA}, defined for
similar purpose. I decide not to call these two functions for two reasons:
o. they don't cover all LTO passes (which will soon be separated into IPO
and post-IPO passes)
o. We have not yet figured out the right passes and the ordering for IPO
and post-IPO stages, meaning this change is only for the time being.
Since LTO passes are registered, we are now able to print IR before and
after particular point.
For OSX users:
--------------
"...-Wl,-mllvm -Wl,-print-after=<pass-name>" will print IR after the
specified pass.
For Other UNIX with GNU gold linker:
------------------------------------
"-Wl,-plugin-opt=-print-after=<pass-name>" should work.
(NOTE: no need for "-Wl,-mllvm")
Strip "-Wl," if flags are fed directly to linker instead of clang/clang++.
llvm-svn: 186853
The problem with running internalize before we're ready to output an object file
is that it may change a 'weak' symbol into an internal one, but that symbol
could be needed by an external object file --- e.g. with arclite.
<rdar://problem/14334895>
llvm-svn: 185882
This is dead code since PIC16 was removed in 2010. The result was an odd mix,
where some parts would carefully pass it along and others would assert it was
zero (most of the object streamer for example).
llvm-svn: 185436
Specifying the load address for Darwin i386 dylibs was a performance
optimization for dyld that is not relevant for x86_64 or arm. We can just
remove this now.
llvm-svn: 183230
Move the processing of the command line options to right before we create the
TargetMachine instead of after.
<rdar://problem/13468287>
llvm-svn: 182611
Update comments, fix * placement, fix method names that are not
used in clang, add a linkInModule that takes a Mode and put it
in Linker.cpp.
llvm-svn: 181099
LTO was always creating an empty llvm.compiler.used. With this patch we
now first check if there is anything to be added first.
Unfortunately, there is no good way to test libLTO in isolation as it needs gold
or ld64, but there are bots doing LTO builds that found this problem.
llvm-svn: 180202
codegen passes. This brings it in to line with clang and llc's codegen setup,
and tidies up the code.
If I understand correctly, adding ModulePasses to a FunctionPassManager is
bogus. It only seems to explode if an added ModulePass depends on a
FunctionPass though, which might be why this code has survived so long.
Fixes <rdar://problem/13386816>.
llvm-svn: 176977
- Consistency with opt (which supports the same option with the same meaning and
description).
- Debugging gold plugin-based linking without optimizations getting in the way.
- Debugging programs linked with the gold plugin while preserving the original
debug info.
- Fine-grained control over LTO passes using the gold plugin in combination with
opt (or clang/dragonegg).
Patch by Cristiano Giuffrida!
llvm-svn: 176257
