This makes it a bit more like a 'real' iterator though I still haven't
gone through to make sure it meets the full requirements. Copy
assignability seems to be required by MSVC's std::find_if, which is its
right.
llvm-svn: 232097
The canonical LLVM directory arrangement places binaries in the 'utils/'
tree when they are used as part of building the project. For example,
the tblgen binaries are built out of 'utils/' trees.
Tools which are not used by any other part of the build, including
testing utilities, are just in the 'tools' directory. For example, in
Clang we have 'c-index-test' which is exactly the same kind of thing as
'linker-script-test'.
Differential Revision: http://reviews.llvm.org/D8269
llvm-svn: 231973
the spec required by std::sort and friends.
Ordering things this way also dramatically simplifies the code as
short-circuit ensures we can skip all of the negative tests.
I've left one FIXME where we're establishing a fairly arbitrary
ordering. Previously, the function compared all types as equal except
for the ones it explicitly handled, but it didn't delegate correctly to
the atomflags when doing so, and so it would fail to be a SWO. The two
possible fixes are to stop comparing the atom flags entirely, or to
establish some arbitrary ordering of the types.
Since it was pure luck which ordering of unequal types we ended up with
previously (the caller was std::sort, not std::stable_sort) I chose to
make the ordering explicit and guaranteed. This seems like the best
conservative approach as I suspect we would want to switch to
stable_sort otherwise in order to have deterministic output.
Differential Revision: http://reviews.llvm.org/D8266
llvm-svn: 231968
This patch implements parsing of the GNU ld MEMORY command [1].
The command and the memory block definitions are parsed as
specified (including the slightly strange "o" and "l" keywords).
Evaluation will be added at a later point in time.
[1] https://sourceware.org/binutils/docs-2.25/ld/MEMORY.html
llvm-svn: 231928
This will be replaced by a more generic class to handle
all the default symbols in an executable, e.g. __init_array.
Differential Revision: http://reviews.llvm.org/D8234
Reviewed by: shankare
llvm-svn: 231906
of the vector. For a vector 'v', '&v[v.size()]' isn't a valid way to
compute a pointer one-past-the-end of the vector. Instead, write the
loop in terms of iterators and save the beginning iterator. Once we have
that we can compute the beginning pointer from the beginning iterator,
and compute the distance which we should increment the beginning pointer
by subtracting the iterators.
What might be simpler would be to convert the function accepting a raw
pointer for begin and end to accept iterators or a range or some other
construct, but I wanted to keep this to a minimal bug-fix change.
This fixes a crash on any debug STL implementation which checks for
indexing out of bounds.
llvm-svn: 231765
The expression evaluation is needed when interpreting linker scripts, in order
to calculate the value for new symbols or to determine a new position to load
sections in memory. This commit extends Expression nodes from the linker script
AST with evaluation functions, and also contains a unit test.
http://reviews.llvm.org/D8156
llvm-svn: 231707
1. Move relocation addendum reading code to the MipsRelocationHandler
class to reduce code duplication.
2. Factor out the relocations calculation code into the separate
function to be ready to handle MIPS N64 ABI relocation chains.
No functional changes.
llvm-svn: 231641
We should not take in account a type of "source" symbol. Cross mode jump
adjustment is requred when target symbol and relocation belong to
different (regular/microMIPS) instruction sets.
llvm-svn: 231639
Previously, getEmptyKey and getTombstoneKey return the same value
in the sense of isEqual defined by the same class, although they
need to be distinct values. This could confuse DenseMap.
We didn't see any issue by this wrong code because we don't delete
elements from the symbol table. We only add or replace elements.
But this is a bug and needs to be fixed anyway.
llvm-svn: 231618
All readers except PE/COFF reader create layout-after edges to preserve
the original symbol order. PE/COFF uses layout-before edges as primary
edges for no reason.
This patch makes PE/COFF reader to create layout-after edges.
Resolver is updated to recognize reverse edges of layout-after edges
in the garbage collection pass.
Now we can retire layout-before edges. I don't do that in this patch
because if I do, I would have updated many tests to replace all
occurrrences of "layout-before" with "layout-after". So that's a TODO.
llvm-svn: 231615
If an output is large, its base relocation section can be also large.
For example, chrome.dll is almost 300 MB, and it has about 9 million
base relocations. Creating the section took 1.5 seconds on my machine.
This patch changes the way to create the section so that we can use
parallel_sort to group base relocations by high bits. This change
makes the linker almost 4% faster for the above test case on my machine.
If I replace parallel_sort with std::sort, performance remains the same,
so single thread performance should remain the same.
This has no functionality change. The output should be identical as
before.
llvm-svn: 231585
All defined symbols from all archive files are inserted to _archiveMap,
so performance of hash table matters here (I'm not trying to convert
all std::maps with DenseMaps). This change seems to make the linker
0.5% - 1% faster for my test case.
llvm-svn: 231584
This patch reverts r231545 "PECOFF: Do not add extraneous symbols
to the dead strip root." CrWinClangLLD buildbot is currently broken.
Since I can't reproduce the issue locally, I'm reverting the most
relevant change.
llvm-svn: 231582
Atoms with fallback atoms are never be added to the symbol table.
However, we added such atoms to _undefines array. We had to call
isCoalescedAway to identify and skip them. We should just stop
adding them in the first place.
This seems to make the linker ~1% faster in my test case.
llvm-svn: 231552
If an undefined symbol is added to the symbol table by the previous
call of SymbolTable::add, SymbolTable::isDefined will always return
false for the same symbol.
llvm-svn: 231551
This is yet another optimization patch. Previously we called
SymbolTable::isDefined() and SymbolTable::findByName() from a very
frequently executed function. Because isDefined calls findByName,
findByName is called twice on each iteration.
findByName is not a cheap function. It computes a hash value for a
given symbol name. When linking C++ programs, it can be expensive
because of C++ mangled long symbols.
This patch reduces the number of call from 2 to 1. Performance
improvements by this patch was larger than I expected. Linking time
of chrome.dll gets almost 5% shorter.
llvm-svn: 231549
Meador Inge