This is apparently a bit of a white lie (they can affect DSPControl for
overflow etc) but similar to how we currently handle floating-point operations.
When it becomes relevant the whole lot can be reviewed properly.
llvm-svn: 199718
Add support to llvm-readobj to decode the actual opcodes. The ARM EHABI opcodes
are a variable length instruction set that describe the operations required for
properly unwinding stack frames.
The primary motivation for this change is to ease the creation of tests for the
ARM EHABI object emission as well as the unwinding directive handling in the ARM
IAS.
Thanks to Logan Chien for an extra test case!
llvm-svn: 199708
This implements the unwind_raw directive for the ARM IAS. The unwind_raw
directive takes the form of a stack offset value followed by one or more bytes
representing the opcodes to be emitted. The opcode emitted will interpreted as
if it were assembled by the opcode assembler via the standard unwinding
directives.
Thanks to Logan Chien for an extra test!
llvm-svn: 199707
The .personalityindex directive is equivalent to the .personality directive with
the ARM EABI personality with the specific index (0, 1, 2). Both of these
directives indicate personality routines, so enhance the personality directive
handling to take into account personalityindex.
Bonus fix: flush the UnwindContext at the beginning of a new function.
Thanks to Logan Chien for additional tests!
llvm-svn: 199706
It was commited as r199628 but reverted in r199628 as causing
regression test failed. It's because of old vervsion of patch
I used to commit. Sorry for mistake.
llvm-svn: 199704
to not guess at a symbol name in some cases.
The problem is that in object files assembled starting at address 0, when
trying to symbolicate something that starts like this:
% cat x.s
_t1:
vpshufd $0x0, %xmm1, %xmm0
the symbolic disassembly can end up like this:
% otool -tV x.o
x.o:
(__TEXT,__text) section
_t1:
0000000000000000 vpshufd $_t1, %xmm1, %xmm0
Which is in this case produced incorrect symbolication.
But it is useful in some cases to use the SymbolLookUp() call back
to guess at some immediate values. For example one like this
that does not have an external relocation entry:
% cat y.s
_t1:
movl $_d1, %eax
.data
_d1: .long 0
% clang -c -arch i386 y.s
% otool -tV y.o
y.o:
(__TEXT,__text) section
_t1:
0000000000000000 movl $_d1, %eax
% otool -rv y.o
y.o:
Relocation information (__TEXT,__text) 1 entries
address pcrel length extern type scattered symbolnum/value
00000001 False long False VANILLA False 2 (__DATA,__data)
So the change is based on it is not likely that an immediate Value
coming from an instruction field of a width of 1 byte, other than branches
and items with relocation, are not likely symbol addresses.
With the change the first case above simply becomes:
% otool -tV x.o
x.o:
(__TEXT,__text) section
_t1:
0000000000000000 vpshufd $0x0, %xmm1, %xmm0
and the second case continues to work as expected.
rdar://14863405
llvm-svn: 199698
when used with symbolic disassembly, add a check that the operand
is an immediate and has not been symbolicated to MCExpr operand.
I’m trying to enable the ‘C’ disassembly API option
LLVMDisassembler_Option_SetInstrComments for darwin’s
otool(1) that uses the llvm disassembler API. The problem is
that the disassembler API can change an immediate operand to
an MCExpr operand if it symbolicates it with the call backs.
And if it does the code in llvm::EmitAnyX86InstComments()
will crash when it assumes these operands are immediates.
The fix for this is very straight forward to just protect the call
to getImm() with a check of isImm(). So if the immediate for
an instruction is symbolicated it simply doesn’t get the X86
verbose assembly comments:
% otool -tV test_asm.o
test_asm.o:
(__TEXT,__text) section
_t1:
0000000000000000 vpshufd $_t1, %xmm1, %xmm0
0000000000000005 retq
0000000000000006 nopw %cs:_t1(%rax,%rax)
_t2:
0000000000000010 vpshufd $-0x1, %xmm0, %xmm0 ## xmm0 = xmm0[3,3,3,3]
0000000000000015 retq
0000000000000016 nopw %cs:_t1(%rax,%rax)
_t3:
0000000000000020 vpshufd $_t1, %xmm1, %xmm0
0000000000000025 retq
0000000000000026 nopw %cs:_t1(%rax,%rax)
_t4:
0000000000000030 vpshufd $0x2d, %xmm0, %xmm0 ## xmm0 = xmm0[1,3,2,0]
0000000000000035 retq
The fact that the immediate $0x0 is being symbolicated at
all in this case is a different problem which my next patch
will address.
rdar://10989286
llvm-svn: 199697
StackProtector keeps a ValueMap of alloca instructions to layout kind tags for
use by PEI and other later passes. When stack coloring replaces one alloca with
a bitcast to another one, the key replacement in this map does not work.
Instead, provide an interface to manage this updating directly. This seems like
an improvement over the old behavior, where the layout map would not get
updated at all when the stack slots were merged. In practice, however, there is
likely no observable difference because PEI only did anything special with
'large array' kinds, and if one large array is merged with another, than the
replacement should already have been a large array.
This is an attempt to unbreak the clang-x86_64-darwin11-RA builder.
llvm-svn: 199684
Add target specific rules for combining vselect dag nodes into movss/movsd
when possible.
If the vector type of the vselect dag node in input is either MVT::v4i13 or
MVT::v4f32, then try to fold according to rules:
1) fold (vselect (build_vector (0, -1, -1, -1)), A, B) -> (movss A, B)
2) fold (vselect (build_vector (-1, 0, 0, 0)), A, B) -> (movss B, A)
If the vector type of the vselect dag node in input is either MVT::v2i64 or
MVT::v2f64 (and we have SSE2), then try to fold according to rules:
3) fold (vselect (build_vector (0, -1)), A, B) -> (movsd A, B)
4) fold (vselect (build_vector (-1, 0)), A, B) -> (movsd B, A)
llvm-svn: 199683
optional DWARF sections, so compiling with -g does not result in
different code being generated for PC-relative loads.
This is reapplying a diet r197922 (__TEXT-only).
llvm-svn: 199681
The way that stack coloring updated MMOs when merging stack slots, while
correct, is suboptimal, and is incompatible with the use of AA during
instruction scheduling. The solution, which involves the use of const_cast (and
more importantly, updating the IR from within an MI-level pass), obviously
requires some explanation:
When the stack coloring pass was originally committed, the code in
ScheduleDAGInstrs::buildSchedGraph tracked possible alias sets by using
GetUnderlyingObject, and all load/store and store/store memory control
dependencies where added between SUs at the object level (where only one
object, that returned by GetUnderlyingObject, was used to identify the object
associated with each MMO). When stack coloring merged stack slots, it would
replace MMOs derived from the remapped alloca with the alloca with which the
remapped alloca was being replaced. Because ScheduleDAGInstrs only used single
objects, and tracked alias sets at the object level, this was a fine solution.
In r169744, (Andy and) I updated the code in ScheduleDAGInstrs to use
GetUnderlyingObjects, and track alias sets using, potentially, multiple
underlying objects for each MMO. This was done, primarily, to provide the
ability to look through PHIs, and provide better scheduling for
induction-variable-dependent loads and stores inside loops. At this point, the
MMO-updating code in stack coloring became suboptimal, because it would clear
the MMOs for (i.e. completely pessimize) all instructions for which r169744
might help in scheduling. Updating the IR directly is the simplest fix for this
(and the one with, by far, the least compile-time impact), but others are
possible (we could give each MMO a small vector of potential values, or make
use of a remapping table, constructed from MFI, inside ScheduleDAGInstrs).
Unfortunately, replacing all MMO values derived from the remapped alloca with
the base replacement alloca fundamentally breaks our ability to use AA during
instruction scheduling (which is critical to performance on some targets). The
reason is that the original MMO might have had an offset (either constant or
dynamic) from the base remapped alloca, and that offset is not present in the
updated MMO. One possible way around this would be to use
GetPointerBaseWithConstantOffset, and update not only the MMO's value, but also
its offset based on the original offset. Unfortunately, this solution would
only handle constant offsets, and for safety (because AA is not completely
restricted to deducing relationships with constant offsets), we would need to
clear all MMOs without constant offsets over the entire function. This would be
an even worse pessimization than the current single-object restriction. Any
other solution would involve passing around a vector of remapped allocas, and
teaching AA to use it, introducing additional complexity and overhead into AA.
Instead, when remapping an alloca, we replace all IR uses of that alloca as
well (optionally inserting a bitcast as necessary). This is even more efficient
that the old MMO-updating code in the stack coloring pass (because it removes
the need to call GetUnderlyingObject on all MMO values), removes the
single-object pessimization in the default configuration, and enables the
correct use of AA during instruction scheduling (all without any additional
overhead).
LLVM now no longer miscompiles itself on x86_64 when using -enable-misched
-enable-aa-sched-mi -misched-bottomup=0 -misched-topdown=0 -misched=shuffle!
Fixed PR18497.
Because the alloca replacement is now done at the IR level, unless the MMO
directly refers to the remapped alloca, the change cannot be seen at the MI
level. As a result, there is no good way to fix test/CodeGen/X86/pr14090.ll.
llvm-svn: 199658
When using AA to break false chain dependencies, we need to track multiple
stores per object in ScheduleDAGInstrs. Historically, we tracked potential alias
chains at the object level, and so all loads of an object would retain
dependencies on any store to that object. With AA, however, this is not
sufficient: non-overlapping stores and loads to the same object all need to be
tested for dependencies separately, we cannot only test all loads to an object
against only the last store (see PR18497 for an explicit example).
To mitigate any unwelcome compile-time impact when not using AA, only one store
is kept in the list per object when not using AA.
This, along with a stack coloring change to come shortly, will provide a test
case, fix PR18497 (and allow LLVM to compile itself using -enable-aa-sched-mi
on x86-64).
llvm-svn: 199657
The addition of IC_OPSIZE_ADSIZE in r198759 wasn't quite complete. It
also turns out to have been unnecessary. The disassembler handles the
AdSize prefix for itself, and doesn't care about the difference between
(e.g.) MOV8ao8 and MOB8ao8_16 definitions. So just let them coexist and
don't worry about it.
llvm-svn: 199654
The disassembler has a special case for 'L' vs. 'W' in its heuristic for
checking for 32-bit and 16-bit equivalents. We could expand the heuristic,
but better just to be consistent in using the 'L' suffix.
llvm-svn: 199652
When disassembling in 16-bit mode the meaning of the OpSize bit is
inverted. Instructions found in the IC_OPSIZE context will actually
*not* have the 0x66 prefix, and instructions in the IC context will
have the 0x66 prefix. Make use of the existing special-case handling
for the 0x66 prefix being in the wrong place, to cope with this.
llvm-svn: 199650
Aside from cleaning up the code, this also adds support for the -code16
environment and actually enables the MODE_16BIT mode that was previously
not accessible.
There is no point adding any testing for 16-bit yet though; basically
nothing will work because we aren't handling the OpSize prefix correctly
for 16-bit mode.
llvm-svn: 199649
various opt verifier commandline options.
Mostly mechanical wiring of the verifier to the new pass manager.
Exercises one of the more unusual aspects of it -- a pass can be either
a module or function pass interchangably. If this is ever problematic,
we can make things more constrained, but for things like the verifier
where there is an "obvious" applicability at both levels, it seems
convenient.
This is the next-to-last piece of basic functionality left to make the
opt commandline driving of the new pass manager minimally functional for
testing and further development. There is still a lot to be done there
(notably the factoring into .def files to kill the current boilerplate
code) but it is relatively uninteresting. The only interesting bit left
for minimal functionality is supporting the registration of analyses.
I'm planning on doing that on top of the .def file switch mostly because
the boilerplate for the analyses would be significantly worse.
llvm-svn: 199646
ADDITIONAL_HEADERS is intended to add header files for IDEs as hint.
For example:
add_llvm_library(LLVMSupport
Host.cpp
ADDITIONAL_HEADERS
Unix/Host.inc
Windows/Host.inc
)
llvm-svn: 199639
coding standards, and instead fix the existing section.
Thanks to Daniel Jasper for pointing out we already had a section
devoted to this topic. Instead of adding sections, just hack on this
section some. Also fix the example in the anonymous namespace section
below it to agree with the new advice.
As a re-cap, this switches the LLVM preferred style to never indent
namespaces. Having two approaches just led to endless (and utterly
pointless) debates about what was "small enough". This wasn't helping
anyone. The no-indent rule is easy to understand and doesn't really make
anything harder to read. Moreover, with tools like clang-format it is
considerably nicer to have simple consistent rules.
llvm-svn: 199637
