llvm-svn: 195105

llvm-svn: 195096

llvm-svn: 195062

llvm-svn: 195051

llvm-svn: 194988

The maximum number of references the file with NativeReferenceIvarsV1 can
contain is 65534. If a file larger than that is converted to Native format,
the conversion will fail without any error message. This caused a subtle bug
that the LLD would produce a broken executable only when input files contain
too many references.

This issue exists since the RoundTripNativeTest is introduced in r193585. Since
then, it seems that nobody have linked any program having more than 65534
relocations with the LLD. Otherwise we would have found it earlier.

llvm-svn: 194987

llvm-svn: 194982

No functionality change.

llvm-svn: 194914

llvm-svn: 194913

llvm-svn: 194911

llvm-svn: 194909

llvm-svn: 194908

end() was evaluated every time through a loop. This patch eliminates it.

llvm-svn: 194894

llvm-svn: 194890

llvm-svn: 194887

llvm-svn: 194877

llvm-svn: 194866

This patch does not change the meaning of the program, but if something's wrong
in the linker or the compiler and the control reaches to the gap of imported
function table, it will stop immediately because of the presence of INT3. If
NOP, it'd fall through to the next call instruction, which is usually a
completely foreign function call.

llvm-svn: 194860

llvm-svn: 194851

llvm-svn: 194847

llvm-svn: 194793

llvm-svn: 194791

Also slightly reduces PECOFFLinkingContext's memory footprint (~128B).

llvm-svn: 194787

llvm-svn: 194784

We can add multiple undefined atoms having the same name to the symbol table.
If such atoms are added, the symbol table compares their canBeNull attributes,
and select one having a stronger constraint. If their canBeNulls are the same,
the choice is arbitrary. Currently it choose the existing one.

This patch changes the preference, so that the symbol table choose the new one
if the new atom has a greater canBeNull or a fallback atom. This shouldn't
change the behavior except the case described below.

A new undefined atom may have a new fallback atom attribute. By choosing the new
atom, we can update the fallback atom during Core Linking. PE/COFF actually need
that. For example, _lseek is an alias for __lseek on Windows. One of an object
file in OLDNAMES.LIB has an undefined atom for _lseek with the fallback to
__lseek. When the linker tries to resolve _read, it supposed to read the file
from OLDNAMES.LIB and use the new fallback from the file. Currently LLD cannot
handle such case because duplicate undefined atoms with the same attributes are
ignored.

Differential Revision: http://llvm-reviews.chandlerc.com/D2161

llvm-svn: 194777

llvm-svn: 194776

llvm-svn: 194768

llvm-svn: 194757

llvm-svn: 194754

llvm-svn: 194746

Writing arguments after the redirection of input ("< somefile") seems a bit
strange. Changes the order.

llvm-svn: 194727

llvm-svn: 194723

llvm-svn: 194722

llvm-svn: 194721

llvm-svn: 194677

llvm-svn: 194675

llvm-svn: 194671

llvm-svn: 194668

YAML files tend to be very large compared to binary formats because of ASCII
format inefficiency. And the YAML reader consumes an excessively large amount
of memory when parsing a large file. It's very slow too.

For example, I observed that 6MB executable became 120MB YAML file, and the
YAML reader consumed more than 1.5GB memory to load it. The YAML reader even
caused OOM error on 32 bit, causing the entire process to fail.

This patch sets the limit on the YAML file size the linker will try to load in
the RoundTripYAML test as a safeguard.

llvm-svn: 194666

llvm-svn: 194643