Commit Graph

254 Commits

Author SHA1 Message Date
Rafael Espindola 089dac7be1 Make Ctx a plain pointer again.
If a struct has a std::unique_ptr member, the logical interpretation
is that that member will be destroyed with the struct.

That is not the case for Ctx. It is has to be deleted earlier and its
lifetime is defined by the functions where the AddressState is
created.

llvm-svn: 316378
2017-10-23 21:12:19 +00:00
Rafael Espindola 849d499e6d Don't call buildSectionOrder multiple times.
This takes linking the linux kernel from 1.52s to 0.58s.

llvm-svn: 316251
2017-10-21 00:05:01 +00:00
Rafael Espindola 3558e24ae8 Remove unused argument.
llvm-svn: 316248
2017-10-20 23:28:19 +00:00
George Rimar ee7c99b63a [ELF] - Make LinkerScript::assignOffsets private. NFC.
llvm-svn: 316073
2017-10-18 12:09:41 +00:00
Rui Ueyama 7ad1e3102a Split LinkerScript::computeInputSections into two functions.
llvm-svn: 315434
2017-10-11 04:50:30 +00:00
Rui Ueyama 722221f5a7 Swap parameters of getSymbolValue.
Usually, a function that does symbol lookup takes symbol name as
its first argument. Also, if a function takes a source location hint,
it is usually the last parameter. So the previous parameter order
was counter-intuitive.

llvm-svn: 315433
2017-10-11 04:34:34 +00:00
Rui Ueyama f0403c601a Rename BytesDataCommand -> ByteCommand.
llvm-svn: 315431
2017-10-11 04:22:09 +00:00
Rui Ueyama 0543343170 Use more precise type.
llvm-svn: 315426
2017-10-11 04:01:13 +00:00
Rui Ueyama 29b240c671 Rename CurAddressState -> Ctx.
We used CurAddressState to capture a dynamic context just like
we use lambdas to capture static contexts. So, CurAddressState
is used everywhere in LinkerScript.cpp. It is worth a shorter
name.

llvm-svn: 315418
2017-10-11 02:45:54 +00:00
Rui Ueyama 183aa2731e Make LinkerScript::addSymbol a private member function.
llvm-svn: 315416
2017-10-11 02:28:39 +00:00
Rui Ueyama 5908c2f877 Rename processCommands -> processSectionCommands.
llvm-svn: 315415
2017-10-11 02:28:28 +00:00
Rui Ueyama a80633ca14 Inline small functions.
llvm-svn: 315414
2017-10-11 02:20:00 +00:00
Rui Ueyama 6b394caaf1 Rename Commands -> SectionCommands.
"Commands" was ambiguous because in the linker script, everything is
a command. We used to handle only SECTIONS commands, and at the time,
it might make sense to call them the commands, but it is no longer
the case. We handle not only SECTIONS but also MEMORY, PHDRS, VERSION,
etc., and they are all commands.

llvm-svn: 315409
2017-10-11 01:50:56 +00:00
Rui Ueyama a323e2a722 Rename HasSections -> HasSectionsComand.
HasSections is true if there is at least one SECTIONS linker
script command, and it is not directly related to whether we have
section objects or not. So I think the new name is better.

llvm-svn: 315405
2017-10-11 01:34:51 +00:00
Rui Ueyama ac27de9dc7 Remove ScriptConfiguration class and move the members to LinkerScript class.
ScriptConfiguration was a class to contain parsed results of
linker scripts. LinkerScript is a class to interpret it.

That ditinction was needed because we haven't instantiated
LinkerScript early (because, IIRC, LinkerScript class was a
ELFT template function). So, when we parse linker scripts,
we couldn't directly store the result to a LinkerScript instance.

Now, that limitation is gone. We instantiate LinkerScript
at the very beginning of our main function. We can directly
store parse results to a LinkerScript instance.

llvm-svn: 315403
2017-10-11 01:19:33 +00:00
Rui Ueyama 18d19687c8 Inline addRegular into addSymbol.
Because addRegular's functionality is tightly coupled with
addSymbol, and the former is called only once, it makes sense
to merge the two functions. This patch also adds comments.

llvm-svn: 315401
2017-10-11 01:03:37 +00:00
Rui Ueyama 4fbe351817 Remove a constructor from ExprValue. NFC.
I think three ctors are too many for this simple class.

llvm-svn: 315394
2017-10-11 00:06:27 +00:00
Rui Ueyama 41ef17bb3c Add comments.
llvm-svn: 315393
2017-10-11 00:01:49 +00:00
Rui Ueyama e03ba02348 Rename ignoreInterpSection -> needsInterpSection.
This should improve consistency. Also added comment.

llvm-svn: 315169
2017-10-08 03:52:15 +00:00
Rui Ueyama 0ae2c24c5d Use llvm::Optional instead of UINT_MAX to represent a null value.
llvm-svn: 315168
2017-10-08 03:45:49 +00:00
Rui Ueyama 656be31174 Make a helper function a non-member function. NFC.
llvm-svn: 315167
2017-10-08 02:54:42 +00:00
Rui Ueyama 872235743d Use llvm::Optional instead of a magic number -1 to represent "no result".
llvm-svn: 315166
2017-10-08 02:44:08 +00:00
Rui Ueyama 9b18f50f79 Remove a trivial function.
llvm-svn: 315164
2017-10-08 02:06:03 +00:00
Rui Ueyama 3f851704c1 Move new lld's code to Common subdirectory.
New lld's files are spread under lib subdirectory, and it isn't easy
to find which files are actually maintained. This patch moves maintained
files to Common subdirectory.

Differential Revision: https://reviews.llvm.org/D37645

llvm-svn: 314719
2017-10-02 21:00:41 +00:00
Rafael Espindola a6acd23c53 Align addresses, not offsets.
This fixes two more cases where we were aligning the offset in a
section, instead of the final address.

llvm-svn: 312983
2017-09-12 00:06:00 +00:00
George Rimar 5f37541c73 [ELF] - Linkerscript: implement REGION_ALIAS.
REGION_ALIAS(alias, region)

Alias names can be added to existing memory regions created with
the MEMORY command. Each name corresponds to at most one
memory region.

Differential revision: https://reviews.llvm.org/D37477

llvm-svn: 312777
2017-09-08 08:23:15 +00:00
Rafael Espindola 8c022ca783 Merge OutputSectionCommand and OutputSection.
This is a bit of a hack, but it is *so* convenient.

Now that we create synthetic linker scripts when none is provided, we
always have to handle paired OutputSection and OutputsectionCommand and
keep a mapping from one to the other.

This patch simplifies things by merging them and creating what used to
be OutputSectionCommands really early.

llvm-svn: 309311
2017-07-27 19:22:43 +00:00
George Rimar aa3541875e [ELF] - Store PhdrEntry values by pointers instead of storing by value.
That is slightly more convinent as allows to store pointer on
program header entry in a more safe way.
 
Change was used in 2 patches currently on review.

Differential revision: https://reviews.llvm.org/D35832

llvm-svn: 309253
2017-07-27 07:46:50 +00:00
Petr Hosek 8b591f592b [ELF] Remove processNonSectionCommands
This method is no longer being used anywhere.

Differential Revision: https://reviews.llvm.org/D35706

llvm-svn: 308706
2017-07-21 01:02:30 +00:00
Peter Smith 906e9a1898 [ELF] Extract temporary state used in assignAddresses()
The assignAddresses() function accumulates state in the LinkerScript that
prevents it from being called multiple times. This change moves the state
into a separate structure AddressState that is created at the start of the
function and disposed of at the end.

CurAddressState is used rather than passing a reference to the state as a
parameter to the functions used by assignAddresses(). This is because the
getSymbolValue function needs to be executed in the context of AddressState
but it is stored in ScriptParser when AddressState is not available.

The AddressState is also used in a limited context by processCommands()

Differential Revision: https://reviews.llvm.org/D34345

llvm-svn: 307367
2017-07-07 09:11:27 +00:00
Rafael Espindola 2126334e08 Move fabricateDefaultCommands earlier.
It is now just after the OutputSections are created, which is as early
as it can possibly go.

llvm-svn: 307225
2017-07-05 23:36:24 +00:00
Rafael Espindola 9f9e99be20 Simplify. NFC.
llvm-svn: 307217
2017-07-05 22:30:04 +00:00
Rafael Espindola cf7347379f Remove a function that is now trivial.
llvm-svn: 307214
2017-07-05 22:25:38 +00:00
Rafael Espindola d7faa9165f Merge createOrphanCommands into addOrphanSections.
This is a bit simpler and avoids a walk over OutputSections.

llvm-svn: 307178
2017-07-05 17:50:43 +00:00
Peter Smith 5aedebff38 [ELF] Extract allocateHeaders() from assignAddresses()
The allocateHeaders() function is called at the end of assignAddresses(), it
decides whether the ELF header and program header table can be allocated to
a PT_LOAD program header. As the function alters state, it prevents
assignAddresses() from being called multiple times.

This change splits out the call to allocateHeaders() from assignAddresses()
this will permit assignAddresses() to be called while processing range
extension thunks without trying to allocateHeaders().

Differential Revision: https://reviews.llvm.org/D34344

llvm-svn: 307131
2017-07-05 09:12:54 +00:00
Rafael Espindola 383971d2a7 Move clearOutputSections before sortSections.
This is probably the main patch left in unifying our intermediary
representation.

It moves the creation of default commands before section sorting. This
has the nice effect that we now have one location where we decide
where an orphan section should be placed.

Before this patch sortSections would decide the relative location of
orphan sections to other sections, but it was up to placeOrphanSection
to decide on the exact location.

We now only sort sections we created since the linker script is
already in the correct order.

llvm-svn: 305512
2017-06-15 21:51:01 +00:00
Rafael Espindola f51c80559c Make OutputSections and OutputSectionCommands globals.
This is similar to what we do for InputSections and makes them easier
to access.

llvm-svn: 305337
2017-06-13 23:26:31 +00:00
Rafael Espindola 7ff9329b7c Move clearOutputSections before createPhdrs. NFC.
llvm-svn: 305156
2017-06-10 22:12:32 +00:00
George Rimar fbb0463f39 [ELF] - Linkerscript: implement NOLOAD section type.
This is PR32351

Each output section may have a type. The type is a keyword in parentheses.
(https://sourceware.org/binutils/docs/ld/Output-Section-Type.html#Output-Section-Type)
This patch support only one type, it is NOLOAD.
If output section has such type, we force it to be SHT_NOBITS. 

More details are available on a review page.

Differential revision: https://reviews.llvm.org/D33647

llvm-svn: 304925
2017-06-07 16:31:08 +00:00
Peter Smith 8e791463ef [ELF] Convert Thunks to use InputSectionDescriptions
Thunks are now generated per InputSectionDescription instead of per
OutputSection. This allows created ThunkSections to be inserted directly
into InputSectionDescription.

Changes in this patch:
- Loop over InputSectionDescriptions to find relocations to Thunks
- Generate a ThunkSection per InputSectionDescription
- Remove synchronize() as we no longer need it
- Move fabricateDefaultCommands() before createThunks

Differential Revision: https://reviews.llvm.org/D33835

llvm-svn: 304887
2017-06-07 09:35:14 +00:00
George Rimar 41c7ab4a3d [ELF] - Linkerscript: improved error reporting.
When linking linux kernel LLD currently reports next errors:

ld: error: unable to evaluate expression: input section .head.text has no output section assigned
ld: error: At least one side of the expression must be absolute
ld: error: At least one side of the expression must be absolute

That does not provide file/line information and overall looks unclear. 
Patch adds location information to ExprValue and that allows
to provide more clear error messages.

Differential revision: https://reviews.llvm.org/D33943

llvm-svn: 304881
2017-06-07 08:54:43 +00:00
Rafael Espindola 8c284acf14 Move finalize to OutputSectionCommands. NFC.
This removes a mapping from OutputSection to OutputSectionCommand and
is another step in moving clearOutputSections earlier.

llvm-svn: 304821
2017-06-06 19:40:01 +00:00
Rafael Espindola 6888072808 Move maybeCompress to OutputSectionCommand.
This removes a call to getCmd and allows us to move
clearOutputSections earlier.

llvm-svn: 304439
2017-06-01 16:57:48 +00:00
Rafael Espindola faf25a7216 Convert a few more uses of OutputSections. NFC.
Also needed to move clearOutputSections earlier.

llvm-svn: 304420
2017-06-01 16:26:28 +00:00
Rafael Espindola 05c4f67cf3 Move name lookup to script parsing time.
We were looking up sections by name during expression evaluation. By
keeping track of forward declarations we can do the lookup during
script parsing.

Doing the lookup earlier will be more efficient when assignAddresses
is run twice and removes two uses of OutputSections.

llvm-svn: 304381
2017-06-01 01:16:50 +00:00
Petr Hosek 3c6de1a66c [ELF] Use late evaluation for ALIGN in expression
While the following expression is handled fine:

  PROVIDE_HIDDEN(newsym = oldsym + address);

The following expression triggers an error because the expression
is evaluated as absolute:

  PROVIDE_HIDDEN(newsym = ALIGN(oldsym, CONSTANT(MAXPAGESIZE)) + address);

To avoid this error, we use late evaluation for ALIGN by making the
alignment an attribute of the expression itself.

Differential Revision: https://reviews.llvm.org/D33629

llvm-svn: 304185
2017-05-30 03:18:28 +00:00
Rafael Espindola 55b169bf5d Move writeTo to OutputSectionCommand.
This reduces how many times we have to map from OutputSection to
OutputSectionCommand. It is a required step to moving
clearOutputSections earlier.

In order to always use writeTo in OutputSectionCommand we have to call
fabricateDefaultCommands for -r links and move section compression
after it.

llvm-svn: 303784
2017-05-24 18:08:04 +00:00
Rafael Espindola 6a1aa8d9b4 Use more strict types. NFC.
By the time we get to linker scripts, all special InputSectionBase
should have been combined into synthetic sections, which are a type of
InputSection. The net result is that we can use InputSection in a few
places that were using InputSectionBase.

llvm-svn: 303702
2017-05-23 22:47:31 +00:00
Rafael Espindola d7dc225888 Use a DenseMap in LinkerScript::getCmd.
This improves many-sections.s with a linker script from 22s to 0.9s.

llvm-svn: 302708
2017-05-10 19:13:38 +00:00
Rafael Espindola fa948c724a Refactor OutputSection to OutputSectionCommand mapping.
We now always use getCmd. I will optimize it in a followup commit.

llvm-svn: 302706
2017-05-10 19:00:23 +00:00