Unfortunately, the PowerPC instruction definitions make heavy use of the
positional operand encoding heuristic to map operands onto bitfield variables
in the instruction definitions. Changing this to use name-based mapping is not
trivial, however, because additional infrastructure needs to be designed to
handle mapping of complex operands (with multiple suboperands) onto multiple
bitfield variables.
In the mean time, this adds support for positionally encoded operands to
FixedLenDecoderEmitter, so that we can generate a disassembler for the PowerPC
backend. To prevent an accidental reliance on this feature, and to prevent an
undesirable interaction with existing disassemblers, a backend must opt-in to
this support by setting the new decodePositionallyEncodedOperands
instruction-set bit to true.
When enabled, this iterates the variables that contribute to the instruction
encoding, just as the encoder does, and emulates the procedure the encoder uses
to map "numbered" operands to variables. The bit range for each variable is
also determined as the encoder determines them. This map is then consulted
during the decoder-generator's loop over operands to decode, allowing the
decoder to understand both position-based and name-based operand-to-variable
mappings.
As noted in the comment on the decodePositionallyEncodedOperands definition,
this support should be removed once it is no longer needed. There should be no
change to existing disassemblers.
llvm-svn: 197691
This is more prep for adding the PowerPC disassembler. FixedLenDecoderEmitter
should recognize PointerLikeRegClass operands as register types, and generate
register-like decoding calls instead of treating them like immediates.
llvm-svn: 197680
Currently SplitBlockAndInsertIfThen requires that branch condition is an
Instruction itself, which is very inconvenient, because it is sometimes an
Operator, or even a Constant.
llvm-svn: 197677
Although --system-libs is expected to use after --libs, it can be used alone.
$ bin/llvm-config --ldflags
-L/path/to/llvm/objroot/lib
$ bin/llvm-config --libs object
-lLLVMObject -lLLVMSupport
$ bin/llvm-config --system-libs
(Blank line. "all" is assumed but nothing is printed.)
-lrt -ldl -ltinfo -lpthread -lz
$ bin/llvm-config --ldflags --libs --system-libs object
-L/path/to/llvm/objroot/lib
-lLLVMObject -lLLVMSupport
-lrt -ldl -ltinfo -lpthread -lz
It is reimplementation of r197380, and workaround for PR3347 and PR8449.
FIXME: Each LLVM component may have its dependent system libs.
llvm-svn: 197664
Stray *Tests might stay after reverting.
FIXME: Could we apply this feature to clang/unittests?
FIXME: Implement this feature to CMake.
llvm-svn: 197661
Different sized address spaces should theoretically work
most of the time now, and since 64-bit add is currently
disabled, using more 32-bit pointers fixes some cases.
llvm-svn: 197659
This adds support for the .inst directive. This is an ARM specific directive to
indicate an instruction encoded as a constant expression. The major difference
between .word, .short, or .byte and .inst is that the latter will be
disassembled as an instruction since it does not get flagged as data.
llvm-svn: 197657
In those set of patches, Ashok changed Module::ResolveSymbolContextForAddress
so that if it failed to find a symbol for a pc, it could back up
the pc value by 1 and re-search for a symbol.
His change to RegisterContextLLDB.cpp partially duplicates that
behavior but it also removes the separate case where we find a
Symbol for the pc address but it's the wrong symbol -- we need to
handle this as well as the lookup-by-pc-finds-no-symbol case.
The most obvious fallout from this regression was that lldb on
Mac OS X couldn't backtrace past __assert_rtn() which tail-calls
abort(). e.g.
(lldb) bt
* thread #1: tid = 0x5d6ea1, 0x00007fff8ee80866 libsystem_kernel.dylib`__pthread_kill + 10, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
* frame #0: 0x00007fff8ee80866 libsystem_kernel.dylib`__pthread_kill + 10
frame #1: 0x00007fff8eb5835c libsystem_pthread.dylib`pthread_kill + 92
frame #2: 0x00007fff8852ab1a libsystem_c.dylib`abort + 125
frame #3: 0x00007fff884f49bf libsystem_c.dylib`__assert_rtn + 321
frame #4: 0x0000000100000f2c a.out`main + 124
(lldb) dis -c 3 -s 0x7fff884f49b3
libsystem_c.dylib`__assert_rtn + 309:
0x7fff884f49b3: movq %rax, -0x11b96242(%rip) ; gCRAnnotations + 8
0x7fff884f49ba: callq 0x7fff8854fd2c ; symbol stub for: abort
libsystem_c.dylib`basename:
0x7fff884f49bf: pushq %rbp
(lldb)
in this case, __assert_rtn() is immediately followed by basename() and
the changes in r190812 didn't back up the pc value to get the correct
function name / unwind info.
<rdar://problem/15367233>
llvm-svn: 197655
This changes the MachineFrameInfo API to use the new SSPLayoutKind information
produced by the StackProtector pass (instead of a boolean flag) and updates a
few pass dependencies (to preserve the SSP analysis).
The stack layout follows the same approach used prior to this change - i.e.,
only LargeArray stack objects will be placed near the canary and everything
else will be laid out normally. After this change, structures containing large
arrays will also be placed near the canary - a case previously missed by the
old implementation.
Out of tree targets will need to update their usage of
MachineFrameInfo::CreateStackObject to remove the MayNeedSP argument.
The next patch will implement the rules for sspstrong and sspreq. The end goal
is to support ssp-strong stack layout rules.
WIP.
Differential Revision: http://llvm-reviews.chandlerc.com/D2158
llvm-svn: 197653
This matches the data in clang which was added by Jakob Stoklund Olesen in
r179596.
Thanks for erikjv on irc for pointing me to the relevant documents:
http://sparc.com/standards/64.psabi.1.35.ps.Z
page 25: Every stack frame must be 16-byte aligned.
http://sparc.com/standards/psABI3rd.pdf
page 3-10: Although the architecture requires only word alignment, software convention and the operating system require every stack frame to be doubleword aligned.
I tried to add a test, but it looks like sparc doesn't implement dynamic stack
realignment. This will be tested in clang shortly.
llvm-svn: 197646
The inalloca attribute is designed to support passing C++ objects by
value in the Microsoft C++ ABI. It behaves the same as byval, except
that it always implies that the argument is in memory and that the bytes
are never copied. This attribute allows the caller to take the address
of an outgoing argument's memory and execute arbitrary code to store
into it.
This patch adds basic IR support, docs, and verification. It does not
attempt to implement any lowering or fix any possibly broken transforms.
When this patch lands, a complete description of this feature should
appear at http://llvm.org/docs/InAlloca.html .
Differential Revision: http://llvm-reviews.chandlerc.com/D2173
llvm-svn: 197645
We started by trying to deserialize decltype(func-param) in a trailing return
type, which causes the function parameter decl to be deserialized, which pulls
in the function decl, which pulls the function type, which pulls the same
decltype() in the return type, and then we crashed.
llvm-svn: 197644