This helps the instruction selector to lower an i64 * i64 -> i128
multiplication into a single instruction on targets which support it.
Patch by Manuel Jacob.
llvm-svn: 203230
Summary:
llvm/MC/MCSectionMachO.h and llvm/Support/MachO.h both had the same
definitions for the section flags. Instead, grab the definitions out of
support.
No functionality change.
Reviewers: grosbach, Bigcheese, rafael
Reviewed By: rafael
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D2998
llvm-svn: 203211
The old system was fairly convoluted:
* A temporary label was created.
* A single PROLOG_LABEL was created with it.
* A few MCCFIInstructions were created with the same label.
The semantics were that the cfi instructions were mapped to the PROLOG_LABEL
via the temporary label. The output position was that of the PROLOG_LABEL.
The temporary label itself was used only for doing the mapping.
The new CFI_INSTRUCTION has a 1:1 mapping to MCCFIInstructions and points to
one by holding an index into the CFI instructions of this function.
I did consider removing MMI.getFrameInstructions completelly and having
CFI_INSTRUCTION own a MCCFIInstruction, but MCCFIInstructions have non
trivial constructors and destructors and are somewhat big, so the this setup
is probably better.
The net result is that we don't create temporary labels that are never used.
llvm-svn: 203204
This patch teaches the DAGCombiner how to fold a binary OR between two
shufflevector into a single shuffle vector when possible.
The rules are:
1. fold (or (shuf A, V_0, MA), (shuf B, V_0, MB)) -> (shuf A, B, Mask1)
2. fold (or (shuf A, V_0, MA), (shuf B, V_0, MB)) -> (shuf B, A, Mask2)
The DAGCombiner can take advantage of the fact that OR is commutative and
compute two possible shuffle masks (Mask1 and Mask2) for the resulting
shuffle node.
Before folding a dag according to either rule 1 or 2, DAGCombiner verifies
that the resulting shuffle mask is legal for the target.
DAGCombiner would firstly try to fold according to 1.; If not possible
then it will try to fold according to 2.
If both Mask1 and Mask2 are illegal then we conservatively don't fold
the OR instruction.
llvm-svn: 203156
This compiles with no changes to clang/lld/lldb with MSVC and includes
overloads to various functions which are used by those projects and llvm
which have OwningPtr's as parameters. This should allow out of tree
projects some time to move. There are also no changes to libs/Target,
which should help out of tree targets have time to move, if necessary.
llvm-svn: 203083
This is consistent with GDB ToT and reduces the number of relocations in
(type and compile) units, substantially reducing relocations and debug
size in fission + type units builds.
llvm-svn: 203082
pointed to by the attribute, rather than the form as a first
step to determining how to hash the values. No functional change
intended.
llvm-svn: 203044
This works by moving the existing code into the DIEValue hierarchy
and using the DwarfDebug pointer off of the AsmPrinter to access
any global information we need.
llvm-svn: 203033
This enables us to figure out where in the debug_loc section our
locations are so that we can eventually hash them. It also helps
remove some special case code in emission. No functional change.
llvm-svn: 203018
Before llvm-mc would print it, but llc was assuming that it would produce
another section changing directive before one was needed. That assumption is
false with inline asm.
Fixes PR19049.
Another option would be to always create the section, but in the asm printer
avoid printing sections changes during initialization. That would work, but
* We do use the fact that llvm-mc prints it in testing. The tests can be changed
if needed.
* A quick poll on IRC suggest that most developers prefer the implicit .text to
be printed.
llvm-svn: 203001
already lived there and it is where it belongs -- this is the in-memory
debug location representation.
This is just cleanup -- Modules can actually cope with this, but that
doesn't make it right. After chatting with folks that have out-of-tree
stuff, going ahead and moving the rest of the headers seems preferable.
llvm-svn: 202960
Patchpoints already did this. Doing it for stackmaps is a convenience
for the runtime in the event that it needs to scratch register to
patch or perform a runtime call thunk.
Unlike patchpoints, we just assume the AnyRegCC calling
convention. This is the only language and target independent calling
convention specific to stackmaps so makes sense. Although the calling
convention is not currently used to select the scratch registers.
llvm-svn: 202943
selection dag (PR19012)
In X86SelectionDagInfo::EmitTargetCodeForMemcpy we check with MachineFrameInfo
to make sure that ESI isn't used as a base pointer register before we choose to
emit rep movs (which clobbers esi).
The problem is that MachineFrameInfo wouldn't know about dynamic allocas or
inline asm that clobbers the stack pointer until SelectionDAGBuilder has
encountered them.
This patch fixes the problem by checking for such things when building the
FunctionLoweringInfo.
Differential Revision: http://llvm-reviews.chandlerc.com/D2954
llvm-svn: 202930
using a full uint16_t with the flag value... which happens to be
0 or 1. Update the class for bool values and rename functions slightly.
llvm-svn: 202921
Currently this code is duplicated across visitSHL, visitSRA and visitSRL. The
plan is to add rotates as clients to this new function.
There is no functional change intended here.
llvm-svn: 202908
source file had already been moved. Also move the unittest into the IR
unittest library.
This may seem an odd thing to put in the IR library but we only really
use this with instructions and it needs the LLVM context to work, so it
is intrinsically tied to the IR library.
llvm-svn: 202842
directly care about the Value class (it is templated so that the key can
be any arbitrary Value subclass), it is in fact concretely tied to the
Value class through the ValueHandle's CallbackVH interface which relies
on the key type being some Value subclass to establish the value handle
chain.
Ironically, the unittest is already in the right library.
llvm-svn: 202824
Move the test for this class into the IR unittests as well.
This uncovers that ValueMap too is in the IR library. Ironically, the
unittest for ValueMap is useless in the Support library (honestly, so
was the ValueHandle test) and so it already lives in the IR unittests.
Mmmm, tasty layering.
llvm-svn: 202821
name might indicate, it is an iterator over the types in an instruction
in the IR.... You see where this is going.
Another step of modularizing the support library.
llvm-svn: 202815
Inside iterate, we scan backwards then scan forwards in a loop. When iteration
is not zero, the last node was just updated so we can skip it. But when
iteration is zero, we can't skip the last node.
For the testing case, fixing this will save a spill and move register copies
from hot path to cold path.
llvm-svn: 202557
The previous PBQP solver was very robust but consumed a lot of memory,
performed a lot of redundant computation, and contained some unnecessarily tight
coupling that prevented experimentation with novel solution techniques. This new
solver is an attempt to address these shortcomings.
Important/interesting changes:
1) The domain-independent PBQP solver class, HeuristicSolverImpl, is gone.
It is replaced by a register allocation specific solver, PBQP::RegAlloc::Solver
(see RegAllocSolver.h).
The optimal reduction rules and the backpropagation algorithm have been extracted
into stand-alone functions (see ReductionRules.h), which can be used to build
domain specific PBQP solvers. This provides many more opportunities for
domain-specific knowledge to inform the PBQP solvers' decisions. In theory this
should allow us to generate better solutions. In practice, we can at least test
out ideas now.
As a side benefit, I believe the new solver is more readable than the old one.
2) The solver type is now a template parameter of the PBQP graph.
This allows the graph to notify the solver of any modifications made (e.g. by
domain independent rules) without the overhead of a virtual call. It also allows
the solver to supply policy information to the graph (see below).
3) Significantly reduced memory overhead.
Memory management policy is now an explicit property of the PBQP graph (via
the CostAllocator typedef on the graph's solver template argument). Because PBQP
graphs for register allocation tend to contain many redundant instances of
single values (E.g. the value representing an interference constraint between
GPRs), the new RASolver class uses a uniquing scheme. This massively reduces
memory consumption for large register allocation problems. For example, looking
at the largest interference graph in each of the SPEC2006 benchmarks (the
largest graph will always set the memory consumption high-water mark for PBQP),
the average memory reduction for the PBQP costs was 400x. That's times, not
percent. The highest was 1400x. Yikes. So - this is fixed.
"PBQP: No longer feasting upon every last byte of your RAM".
Minor details:
- Fully C++11'd. Never copy-construct another vector/matrix!
- Cute tricks with cost metadata: Metadata that is derived solely from cost
matrices/vectors is attached directly to the cost instances themselves. That way
if you unique the costs you never have to recompute the metadata. 400x less
memory means 400x less cost metadata (re)computation.
Special thanks to Arnaud de Grandmaison, who has been the source of much
encouragement, and of many very useful test cases.
This new solver forms the basis for future work, of which there's plenty to do.
I will be adding TODO notes shortly.
- Lang.
llvm-svn: 202551
This extract-and-trunc vector optimization cannot work for i1 values as
currently implemented, and so I'm disabling this for now for i1 values. In the
future, this can be fixed properly.
Soon I'll commit support for i1 CR bit tracking in the PowerPC backend, and
this will be covered by one of the existing regression tests.
llvm-svn: 202449
This is a temporary workaround for native arm linux builds:
PR18996: Changing regalloc order breaks "lencod" on native arm linux builds.
llvm-svn: 202433
scan the register file for sub- and super-registers.
No functionality change intended.
(Tests are updated because the comments in the assembler output are
different.)
llvm-svn: 202416
any ranges - this includes CU ranges where we were previously emitting an
end list marker even if we didn't have a list.
Testcase includes a test for line table only code emission as the problem
was noticed while writing this test.
llvm-svn: 202357
any ranges to the list of ranges for the CU as we don't want to emit
them anyway. This ensures that we will still emit ranges if we have
a compile unit compiled with only line tables and one compiled with
full debug info requested (we'll emit for the one with full debug info).
Update testcase metadata accordingly to continue emitting ranges.
llvm-svn: 202333
This handles pathological cases in which we see 2x increase in spill
code for large blocks (~50k instructions). I don't have a unit test
for this behavior.
Fixes rdar://16072279.
llvm-svn: 202304
The aggressive anti-dependency breaker scans instructions, bottom-up, within the
scheduling region in order to find opportunities where register renaming can
be used to break anti-dependencies.
Unfortunately, the aggressive anti-dep breaker was treating a register definition
as defining all of that register's aliases (including super registers). This behavior
is incorrect when the super register is live and there are other definitions of
subregisters of the super register.
For example, given the following sequence:
%CR2EQ<def> = CROR %CR3UN, %CR3UN<kill>
%CR2GT<def> = IMPLICIT_DEF
%X4<def> = MFOCRF8 %CR2
the analysis of the first subregister definition would work as expected:
Anti: %CR2GT<def> = IMPLICIT_DEF
Def Groups: CR2GT=g194->g0(via CR2)
Antidep reg: CR2GT (zero group)
Use Groups:
but the analysis of the second one would not:
Anti: %CR2EQ<def> = CROR %CR3UN, %CR3UN<kill>
Def Groups: CR2EQ=g195
Antidep reg: CR2EQ
Rename Candidates for Group g195: ...
because, when processing the %CR2GT<def>, we'd mark all super registers of
%CR2GT (%CR2 in this case) as defined. As a result, when processing
%CR2EQ<def>, %CR2 no longer appears to be live, and %CR2EQ<def>'s group is not
%unioned with the %CR2 group.
I don't have an in-tree test case for this yet (and even if I did, I don't have
a small one).
llvm-svn: 202294
Variadic functions have an unspecified parameter tag after the last
argument. In IR this is represented as an unspecified parameter in the
subroutine type.
Paired commit with CFE r202185.
rdar://problem/13690847
This re-applies r202184 + a bugfix in DwarfDebug's argument handling.
llvm-svn: 202188
Variadic functions have an unspecified parameter tag after the last
argument. In IR this is represented as an unspecified parameter in the
subroutine type.
Paired commit with CFE.
rdar://problem/13690847
llvm-svn: 202184
The function with uwtable attribute might be visited by the
stack unwinder, thus the link register should be considered
as clobbered after the execution of the branch and link
instruction (i.e. the definition of the machine instruction
can't be ignored) even when the callee function are marked
with noreturn.
llvm-svn: 202165
After this I will set the default back to F_None. The advantage is that
before this patch forgetting to set F_Binary would corrupt a file on windows.
Forgetting to set F_Text produces one that cannot be read in notepad, which
is a better failure mode :-)
llvm-svn: 202052
This commit moves getSLEB128Size() and getULEB128Size() from
MCAsmInfo to LEB128.h and removes some copy-and-paste code.
Besides, this commit also adds some unit tests for the LEB128
functions.
llvm-svn: 201937
CodeGenPrepare uses extensively TargetLowering which is part of libLLVMCodeGen.
This is a layer violation which would introduce eventually a dependence on
CodeGen in ScalarOpts.
Move CodeGenPrepare into libLLVMCodeGen to avoid that.
Follow-up of <rdar://problem/15519855>
llvm-svn: 201912
shifted mask rather than masking and shifting separately.
The patch adds this transformation to the DAGCombiner:
(shl (and (setcc:i8v16 ...) N01C) N1C) -> (and (setcc:i8v16 ...) N01C<<N1C)
<rdar://problem/16054492>
Patch by Adam Nemet <anemet@apple.com>
llvm-svn: 201906
The lowering of the frame index for stackmaps and patchpoints requires some
target-specific magic and should therefore be handled in the target-specific
eliminateFrameIndex method.
This is related to <rdar://problem/16106219>
llvm-svn: 201904
We were just emitting a label for this section for no real reason - this
caused us to emit the section even though we never put anything in it.
Not bothering with a test (though not adamantly anti-test) because it
seems somewhat arbitrary to test for the absence of this section anymore
than the absence of any other section.
llvm-svn: 201876
This replaces the old NoIntegratedAssembler with at TargetOption. This is
more flexible and will be used to forward clang's -no-integrated-as option.
llvm-svn: 201836
passing down an AsmPrinter instance so we could compute the size of
the block which could be target specific. All of the test cases in
the unittest don't have any target specific data so we can use a NULL
AsmPrinter there. This also depends upon block data being added as
integers.
We can now hash the entire fission-cu.ll compile unit so turn the
flag on there with the hash value.
llvm-svn: 201752
TargetLoweringBase is implemented in CodeGen, so before this patch we had
a dependency fom Target to CodeGen. This would show up as a link failure of
llvm-stress when building with -DBUILD_SHARED_LIBS=ON.
This fixes pr18900.
llvm-svn: 201711
r201608 made llvm corretly handle private globals with MachO. r201622 fixed
a bug in it and r201624 and r201625 were changes for using private linkage,
assuming that llvm would do the right thing.
They all got reverted because r201608 introduced a crash in LTO. This patch
includes a fix for that. The issue was that TargetLoweringObjectFile now has
to be initialized before we can mangle names of private globals. This is
trivially true during the normal codegen pipeline (the asm printer does it),
but LTO has to do it manually.
llvm-svn: 201700
When outputting an object we check its section to find its name, but when
looking for the section with -ffunction-section we look for the symbol name.
Break the loop by requesting a name with the private prefix when constructing
the section name. This matches the behavior before r201608.
llvm-svn: 201622
The IR
@foo = private constant i32 42
is valid, but before this patch we would produce an invalid MachO from it. It
was invalid because it would use an L label in a section where the liker needs
the labels in order to atomize it.
One way of fixing it would be to just reject this IR in the backend, but that
would not be very front end friendly.
What this patch does is use an 'l' prefix in sections that we know the linker
requires symbols for atomizing them. This allows frontends to just use
private and not worry about which sections they go to or how the linker handles
them.
One small issue with this strategy is that now a symbol name depends on the
section, which is not available before codegen. This is not a problem in
practice. The reason is that it only happens with private linkage, which will
be ignored by the non codegen users (llvm-nm and llvm-ar).
llvm-svn: 201608
alongside DIEBlock and replace uses accordingly. Use DW_FORM_exprloc
in DWARF4 and later code. Update testcases.
Adding a DIELoc instead of using extra forms inside DIEBlock so
that we can keep location expressions separate from other uses. No
direct use at the moment, however, it's not a lot of code and
using a separately named class keeps it somewhat more obvious
what's going on in various locations.
llvm-svn: 201481
This broke in r185459 while TLS support was being generalized to handle
non-symbol TLS representations.
I thought about/tried having an enum rather than a bool to track the
TLS-ness of the address table entry, but namespaces and naming seemed
more hassle than it was worth for only one caller that needed to specify
this.
llvm-svn: 201469
Type units will share the statement list of their defining compile unit.
This is a tradeoff that reduces .o debug info size at the cost of some
linked debug info size (since the contents of those string tables won't
be deduplicated along with the type unit) which seems right for now.
llvm-svn: 201445
These types have an out of line virtual function each (emitHeader at
least) so they won't have weak vtables - no need for more than that.
llvm-svn: 201444
This probably also addresses the FIXME in the fission case regarding
multiple compile units, though I haven't tested that.
This code still confuses me (the literal zero offset makes little sense,
the limitations surrounding asm output I'm not sure about either - but
perhaps we should just always emit one line table? Or should we not rely
on .loc/.file even in assembly so we can produce the same output between
asm and object output?) but this maintains the existing functionality.
llvm-svn: 201441
Recommitting r201380 (reverted in r201389)
Recommitting r201351 and r201355 (reverted in r201351 and r201355)
We weren't emitting the an empty (header only) line table when the line
table was empty - this made the DWARF invalid (the compile unit would
point to the zero-size debug_lines section where there should've been an
empty line table but there was nothing at all). Fix that, and as a
consequence this works around/addresses PR18809.
Also, we emit a non-empty line table to workaround a darwin linker bug,
so XFAILing on darwin too.
Also, mark the test as 'REQUIRES: object-emission' because it does.
llvm-svn: 201429
Recommitting r201351 and r201355 (reverted in r201351 and r201355)
We weren't emitting the an empty (header only) line table when the line
table was empty - this made the DWARF invalid (the compile unit would
point to the zero-size debug_lines section where there should've been an
empty line table but there was nothing at all). Fix that, and as a
consequence this works around/addresses PR18809.
llvm-svn: 201380
Summary:
AsmPrinter::EmitInlineAsm() will no longer use the EmitRawText() call for
targets with mature MC support. Such targets will always parse the inline
assembly (even when emitting assembly). Targets without mature MC support
continue to use EmitRawText() for assembly output.
The hasRawTextSupport() check in AsmPrinter::EmitInlineAsm() has been replaced
with MCAsmInfo::UseIntegratedAs which when true, causes the integrated assembler
to parse inline assembly (even when emitting assembly output). UseIntegratedAs
is set to true for targets that consider any failure to parse valid assembly
to be a bug. Target specific subclasses generally enable the integrated
assembler in their constructor. The default value can be overridden with
-no-integrated-as.
All tests that rely on inline assembly supporting invalid assembly (for example,
those that use mnemonics such as 'foo' or 'hello world') have been updated to
disable the integrated assembler.
Changes since review (and last commit attempt):
- Fixed test failures that were missed due to configuration of local build.
(fixes crash.ll and a couple others).
- Fixed tests that happened to pass because the local build was on X86
(should fix 2007-12-17-InvokeAsm.ll)
- mature-mc-support.ll's should no longer require all targets to be compiled.
(should fix ARM and PPC buildbots)
- Object output (-filetype=obj and similar) now forces the integrated assembler
to be enabled regardless of default setting or -no-integrated-as.
(should fix SystemZ buildbots)
Reviewers: rafael
Reviewed By: rafael
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D2686
llvm-svn: 201333
This fix checks the original LLVM IR node to identify opaque constants by
looking for the bitcast-constant pattern. Originally we looked at the generated
SDNode, but this might lead to incorrect results. The SDNode could have been
generated by an constant expression that was folded to a constant.
This fixes <rdar://problem/16050719>
llvm-svn: 201291
We are now no longer relying on the target-specific call lowering implementation
to lower a stackmap intrinsic call. Instead we perform the call lowering in a
target-independent way directly in the stackmap lowering code. This simplifies
the code and removes the need to fixup the code after the target-specific call
lowering.
llvm-svn: 201263
The ID type for the stackmap and patchpoint intrinsics are in both cases i64.
This fixes an zero extend in the SelectionDAGBuilder that still used i32. This
also updates the target independent instructions STACKMAP and PATCHPOINT to use
the correct type.
llvm-svn: 201262
Summary:
AsmPrinter::EmitInlineAsm() will no longer use the EmitRawText() call for targets with mature MC support. Such targets will always parse the inline assembly (even when emitting assembly). Targets without mature MC support continue to use EmitRawText() for assembly output.
The hasRawTextSupport() check in AsmPrinter::EmitInlineAsm() has been replaced with MCAsmInfo::UseIntegratedAs which when true, causes the integrated assembler to parse inline assembly (even when emitting assembly output). UseIntegratedAs is set to true for targets that consider any failure to parse valid assembly to be a bug. Target specific subclasses generally enable the integrated assembler in their constructor. The default value can be overridden with -no-integrated-as.
All tests that rely on inline assembly supporting invalid assembly (for example, those that use mnemonics such as 'foo' or 'hello world') have been updated to disable the integrated assembler.
Reviewers: rafael
Reviewed By: rafael
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D2686
llvm-svn: 201237
There's still one piece missing here, which is adding the
DW_AT_stmt_list to the type unit that refer's to the compile unit's line
table. Working on that.
llvm-svn: 201198
This is preliminary work to fix type unit file strings so they appear in
their originating CU's line table - but it's also just good/simple
cleanup, so I'm committing it ahead of time.
llvm-svn: 201195
We used to be pretty vague about what debug entities were what, with
many conditionals to silently drop/skip/accept things. These don't seem
to be relevant anymore.
llvm-svn: 201194
Debug info: Emit values in subregisters that do not have a separate
DWARF register number by emitting a super-register + DW_OP_bit_piece.
This is necessary because on x86_64, there are no DWARF register numbers
for i386-style subregisters.
Fixes a bunch of FIXMEs.
rdar://problem/16015314
llvm-svn: 201190
This comes up in empty files or files containing #file directives that
never reference the actual source file name. Came up in a small test of
line tables I was playing with.
llvm-svn: 201187
DWARF register number by emitting a super-register + DW_OP_bit_piece.
This is necessary because on x86_64, there are no DWARF register numbers
for i386-style subregisters.
Fixes a bunch of FIXMEs.
rdar://problem/16015314
llvm-svn: 201180
BUILD_VECTOR nodes, e.g.:
(concat_vectors (BUILD_VECTOR a1, a2, a3, a4), (BUILD_VECTOR b1, b2, b3, b4))
->
(BUILD_VECTOR a1, a2, a3, a4, b1, b2, b3, b4)
This fixes an issue with AVX, where a sequence was not recognized as a 256-bit
vbroadcast due to the concat_vectors.
llvm-svn: 201158
These methods normally call each other and it is really annoying if the
arguments are in different order. The more common rule was that the arguments
specific to call are first (GV, Encoding, Suffix) and the auxiliary objects
(Mang, TM) come after. This patch changes the exceptions.
llvm-svn: 201044
This solves a problem where a def machine operand has no uses but has
not been marked dead. In this case, the initial RP analysis was being
extra precise and determining from LiveIntervals the the register was
actually dead. This caused us to omit the register from the RP
tracker's block live out. That's all good, but the per-instruction
summary still accounted for it as a valid def. This could cause an
assertion in the tracker later when we underflow pressure.
This is from a bug report on an out-of-tree target. It is not
reproducible on well-behaved targets. I'm just making an obvious fix
without unit test.
llvm-svn: 200941
In a previous commit (r199818) we added a const_cast to an existing
subtarget info instead of creating a new one so that we could reuse
it when creating the TargetAsmParser for parsing inline assembly.
This cast was necessary because we needed to reuse the existing STI
to avoid generating incorrect code when the inline asm contained
mode-switching directives (e.g. .code 16).
The root cause of the failure was that there was an implicit sharing
of the STI between the parser and the MCCodeEmitter. To fix a
different but related issue, we now explicitly pass the STI to the
MCCodeEmitter (see commits r200345-r200351).
The const_cast is no longer necessary and we can now create a fresh
STI for the inline asm parser to use.
Differential Revision: http://llvm-reviews.chandlerc.com/D2709
llvm-svn: 200929
The aim in this patch is to reduce work that VirtRegRewriter needs to do when
telling MachineRegisterInfo which physregs are in use. Up until now
VirtRegRewriter::rewrite has been doing rewriting and populating def info and
then proceeding to set whether a physreg is used based this info for every
physreg that the target provides. This can be expensive when a target has an
unusually high number of supported physregs, and is a noticeable chunk of
compile time for small programs on such targets.
So to reduce compile time, this patch simply adds the use of a SparseSet to the
rewrite function that is used to flag each physreg that is encountered in a
MachineFunction. Afterward, rather than iterating over the set of all physregs
for a given target to set the physregs used in MachineRegisterInfo, the new way
is to iterate over the set of physregs that were actually encountered and set
in the SparseSet. This improves compile time because the existing rewrite
function was iterating over all MachineOperands already, and because the
iterations afterward to setPhysRegUsed is reduced by use of the SparseSet data.
llvm-svn: 200919
programs on targets with large register files. The root of the compile time
overhead was in the use of llvm::SmallVector to hold PhysRegEntries, which
resulted in slow-down from calling llvm::SmallVector::assign(N, 0). In contrast
std::vector uses the faster __platform_bzero to zero out primitive buffers when
assign is called, while SmallVector uses an iterator.
The fix for this was simply to replace the SmallVector with a dynamically
allocated buffer and to initialize or reinitialize the buffer based on the
total registers that the target architecture requires. The changes support
cases where a pass manager may be reused for different targets, and note that
the PhysRegEntries is allocated using calloc mainly for good for, and also to
quite tools like Valgrind (see comments for more info on this).
There is an rdar to track the fact that SmallVector doesn't have platform
specific speedup optimizations inside of it for things like this, and I'll
create a bugzilla entry at some point soon as well.
TL;DR: This fix replaces the expensive llvm::SmallVector<unsigned
char>::assign(N, 0) with a call to calloc for N bytes which is much faster
because SmallVector's assign uses iterators.
llvm-svn: 200917
large register files. The omission of Queries.clear() is perfectly safe because
LiveIntervalUnion::Query doesn't contain any data that needs freeing and
because LiveRegMatrix::runOnFunction happens to reset the OwningArrayPtr
holding Queries every time it is run, so there's no need to zero out the
queries either. Not having to do this for very large numbers of physregs
is a noticeable constant cost reduction in compilation of small programs.
llvm-svn: 200913
During DAGCombine visitShiftByConstant assumes that certain binary operations
with only constant operands can always be folded successfully. This is no longer
true when the constant is opaque. This commit fixes visitShiftByConstant by not
performing the optimization for opaque constants. Otherwise we would end up in
an infinite DAGCombine loop.
llvm-svn: 200900
find a register.
The idea is to choose a color for the variable that cannot be allocated and
recolor its interferences around. Unlike the current register allocation scheme,
it is allowed to change the color of an already assigned (but maybe not
splittable or spillable) live interval while propagating this change to its
neighbors.
In other word, there are two things that may help finding an available color:
- Already assigned variables (RS_Done) can be recolored to different color.
- The recoloring allows to catch solutions that needs to touch more that just
the neighbors of the current allocated variable.
E.g.,
vA can use {R1, R2 }
vB can use { R2, R3}
vC can use {R1 }
Where vA, vB, and vC cannot be split anymore (they are reloads for instance) and
they all interfere.
vA is assigned R1
vB is assigned R2
vC tries to evict vA but vA is already done.
=> Regular register allocation heuristic fails.
Last chance recoloring kicks in:
vC does as if vA was evicted => vC uses R1.
vC is marked as fixed.
vA needs to find a color.
None are available.
vA cannot evict vC: vC is a fixed virtual register now.
vA does as if vB was evicted => vA uses R2.
vB needs to find a color.
R3 is available.
Recoloring => vC = R1, vA = R2, vB = R3.
<rdar://problem/15947839>
llvm-svn: 200883
A bunch of test cases needed to be cleaned up for this, many my fault -
when implementid imported modules I updated test cases by simply
duplicating the prior metadata field - which wasn't always the empty
metadata entry.
llvm-svn: 200731
This changes the PrologueEpilogInserter and LocalStackSlotAllocation passes to
follow the extended stack layout rules for sspstrong and sspreq.
The sspstrong layout rules are:
1. Large arrays and structures containing large arrays (>= ssp-buffer-size)
are closest to the stack protector.
2. Small arrays and structures containing small arrays (< ssp-buffer-size) are
2nd closest to the protector.
3. Variables that have had their address taken are 3rd closest to the
protector.
Differential Revision: http://llvm-reviews.chandlerc.com/D2546
llvm-svn: 200601
Calls with inalloca are lowered by skipping all stores for arguments
passed in memory and the initial stack adjustment to allocate argument
memory.
Now the frontend is responsible for the memory layout, and the backend
doesn't have to do any work. As a result these changes are pretty
minimal.
Reviewers: echristo
Differential Revision: http://llvm-reviews.chandlerc.com/D2637
llvm-svn: 200596
Allocas marked inalloca are never static, but we were trying to put them
into the static alloca map if they were in the entry block. Also add an
assertion in x86 fastisel.
llvm-svn: 200593
algorithm. Sink the 'A' + Attribute hash into each form so we don't
have to check valid forms before deciding whether or not we're going
to hash which will let the default be to return without doing anything.
llvm-svn: 200571
This ensures DWARF consumers don't confuse these references for
definitions. I'd argue it might be nice to improve debuggers so we don't
need this, but it's just one field in an abbreviation anyway - so it
doesn't seem worth the fight.
llvm-svn: 200569
when the input is a concat_vectors and the insert replaces one of the
concat halves:
Lower half: fold (insert_subvector (concat_vectors X, Y), Z) ->
(concat_vectors Z, Y)
Upper half: fold (insert_subvector (concat_vectors X, Y), Z) ->
(concat_vectors X, Z)
This can be seen with the following IR:
define <8 x float> @lower_half(<4 x float> %v1, <4 x float> %v2, <4 x
float> %v3) {
%1 = shufflevector <4 x float> %v1, <4 x float> %v2, <8 x i32> <i32
0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
%2 = tail call <8 x float> @llvm.x86.avx.vinsertf128.ps.256(<8 x
float> %1, <4 x float> %v3, i8 0)
The vinsertf128 intrinsic is converted into an insert_subvector node
in SelectionDAGBuilder.cpp.
Using AVX, without the patch this generates two vinsertf128 instructions:
vinsertf128 $1, %xmm1, %ymm0, %ymm0
vinsertf128 $0, %xmm2, %ymm0, %ymm0
With the patch this is optimized into:
vinsertf128 $1, %xmm1, %ymm2, %ymm0
Patch by Robert Lougher.
llvm-svn: 200506
When converting from "or + br" to two branches, or converting from
"and + br" to two branches, we correctly update the edge weights of
the two branches.
The previous attempt at r200431 was reverted at r200434 because of
two testing case failures. I modified my patch a little, but forgot
to re-run "make check-all".
Testing case CodeGen/ARM/lsr-unfolded-offset.ll is updated because of
the patch's impact on branch probability which causes changes in
spill placement.
llvm-svn: 200502
When converting from "or + br" to two branches, or converting from
"and + br" to two branches, we correctly update the edge weights of
the two branches.
llvm-svn: 200431
This commit only handles IfConvertTriangle. To update edge weights
of a successor, one interface is added to MachineBasicBlock:
/// Set successor weight of a given iterator.
setSuccWeight(succ_iterator I, uint32_t weight)
An existing testing case test/CodeGen/Thumb2/v8_IT_5.ll is updated,
since we now correctly update the edge weights, the cold block
is placed at the end of the function and we jump to the cold block.
llvm-svn: 200428
module since there's no range guarantee that we could make given
output order. This also fixes up the testcases that have multiple
CUs to have the correct range offset.
llvm-svn: 200422
After all hard work to implement the EHABI and with the test-suite
passing, it's time to turn it on by default and allow users to
disable it as a work-around while we fix the eventual bugs that show
up.
This commit also remove the -arm-enable-ehabi-descriptors, since we
want the tables to be printed every time the EHABI is turned on
for non-Darwin ARM targets.
Although MCJIT EHABI is not working yet (needs linking with the right
libraries), this commit also fixes some relocations on MCJIT regarding
the EH tables/lib calls, and update some tests to avoid using EH tables
when none are needed.
The EH tests in the test-suite that were previously disabled on ARM
now pass with these changes, so a follow-up commit on the test-suite
will re-enable them.
llvm-svn: 200388
Make sure that we don't introduce illegal build_vector dag nodes
when trying to fold a sign_extend of a build_vector.
This fixes a regression introduced by r200234.
Added test CodeGen/X86/fold-vector-sext-crash.ll
to verify that llc no longer crashes with an assertion failure
due to an illegal build_vector of type MVT::v4i64.
Thanks to Ilia Filippov for spotting this regression and for
providing a reproducible test case.
llvm-svn: 200313
Before this patch we used getIntImmCost from TargetTransformInfo to determine if
a load of a constant should be converted to just a constant, but the threshold
for this was set to an arbitrary value. This value works well for the two
targets (X86 and ARM) that implement this target-hook, but it isn't
target-independent at all.
Now targets have the possibility to decide directly if this optimization should
be performed. The default value is set to false to preserve the current
behavior. The target hook has been moved to TargetLowering, which removed the
last use and need of TargetTransformInfo in SelectionDAG.
llvm-svn: 200271
code to see if we're emitting a function into a non-default
text section. This is still a less-than-ideal solution, but more
contained than r199871 to determine whether or not we're emitting
code into an array of comdat sections.
llvm-svn: 200269
Also update the comment, since it actually produces a
select (setcc) instead of select_cc.
It was checking and using the setcc result type for the
type of the sext, instead of the type of the compared items.
In my problem case, the sext was to i32 and was used as the setcc type,
but the expected type was i64.
No test since I haven't been able to hit the problem with
this on any in-tree targets.
llvm-svn: 200249
This patch teaches the DAGCombiner how to fold a sext/aext/zext dag node when
the operand in input is a build vector of constants (or UNDEFs).
The inability to fold a sext/zext of a constant build_vector was the root
cause of some pcg bugs affecting vselect expansion on x86-64 with AVX support.
Before this change, the DAGCombiner only knew how to fold a sext/zext/aext of a
ConstantSDNode.
llvm-svn: 200234
This commit allows LLVM MC to process .cfi_startproc directives when
they are followed by an additional `simple' identifier. This signals to
elide the emission of target specific CFI instructions that would
normally occur initially.
This fixes PR16587.
Differential Revision: http://llvm-reviews.chandlerc.com/D2624
llvm-svn: 200227
Issue outcomes from DAGCombiner::MergeConsequtiveStores, more precisely from
mem-ops sequence sorting.
Consider, how MergeConsequtiveStores works for next example:
store i8 1, a[0]
store i8 2, a[1]
store i8 3, a[1] ; a[1] again.
return ; DAG starts here
1. Method will collect all the 3 stores.
2. It sorts them by distance from the base pointer (farthest with highest
index).
3. It takes first consecutive non-overlapping stores and (if possible) replaces
them with a single store instruction.
The point is, we can't determine here which 'store' instruction
would be the second after sorting ('store 2' or 'store 3').
It happens that 'store 3' would be the second, and 'store 2' would be the third.
So after merging we have the next result:
store i16 (1 | 3 << 8), base ; is a[0] but bit-casted to i16
store i8 2, a[1]
So actually we swapped 'store 3' and 'store 2' and got wrong contents in a[1].
Fix: In sort routine just also take into account mem-op sequence number.
llvm-svn: 200201
There are currently two issues, of which I currently know, that prevent TBAA
from being correctly usable in CodeGen:
1. Stack coloring does not update TBAA when merging allocas. This is easy
enough to fix, but is not the largest problem.
2. CGP inserts ptrtoint/inttoptr pairs when sinking address computations.
Because BasicAA does not handle inttoptr, we'll often miss basic type punning
idioms that we need to catch so we don't miscompile real-world code (like LLVM).
I don't yet have a small test case for this, but this fixes self hosting a
non-asserts build of LLVM on PPC64 when using -enable-aa-sched-mi and -misched=shuffle.
llvm-svn: 200093
This option (which is !NDEBUG only) allows restricting the use of alias
analysis in DAGCombiner to a specific function. This has proved extremely
valuable to isolating bugs related to this feature, and mirrors the
misched-only-func option provided by the new instruction scheduler.
llvm-svn: 200088
This commit caused -Woverloaded-virtual warnings. The two new
TargetTransformInfo::getIntImmCost functions were only added to the superclass,
and to the X86 subclass. The other targets were not updated, and the
warning highlighted this by pointing out that e.g. ARMTTI::getIntImmCost was
hiding the two new getIntImmCost variants.
We could pacify the warning by adding "using TargetTransformInfo::getIntImmCost"
to the various subclasses, or turning it off, but I suspect that it's wrong to
leave the functions unimplemnted in those targets. The default implementations
return TCC_Free, which I don't think is right e.g. for ARM.
llvm-svn: 200058
Retry commit r200022 with a fix for the build bot errors. Constant expressions
have (unlike instructions) module scope use lists and therefore may have users
in different functions. The fix is to simply ignore these out-of-function uses.
llvm-svn: 200034
DAGCombiner::GatherAllAliases, which is only used when AA used is enabled
during DAGCombine, had a fundamentally incorrect assumption for which this
change compensates. GatherAllAliases, which is used to find aliasing
predecessor chain nodes (so that a better chain can be selected for a load or
store to enable subsequent optimizations) assumed that walking up the chain
would always catch all possibly-aliasing loads and stores. This is not true: To
really find all aliases, we also need to search for aliases through the value
operand of a store, etc. Consider the following situation:
Token1 = ...
L1 = load Token1, %52
S1 = store Token1, L1, %51
L2 = load Token1, %52+8
S2 = store Token1, L2, %51+8
Token2 = Token(S1, S2)
L3 = load Token2, %53
S3 = store Token2, L3, %52
L4 = load Token2, %53+8
S4 = store Token2, L4, %52+8
If we search for aliases of S3 (which loads address %52), and we look only
through the chain, then we'll miss the trivial dependence on L1 (which loads
from %52). We then might change all loads and stores to use Token1 as their
chain operand, which could result in copying %53 into %52 before copying
%52 into %51 (which should happen first).
The problem is, however, that searching for such data dependencies can become
expensive, and the cost is not directly related to the chain depth. Instead,
we'll rule out such configurations by insisting that we've visited all chain
users (except for users of the original chain, which is not necessary). When
doing this, we need to look through nodes we don't care about (otherwise,
things like register copies will interfere with trivial use cases).
Unfortunately, I don't have a small test case for this problem. Creating the
underlying situation is not hard (a pair of memcpys will do it), but arranging
for the default instruction schedule to be incorrect is very fragile.
This unbreaks self hosting on PPC64 when using
-mllvm -combiner-global-alias-analysis -mllvm -combiner-alias-analysis.
llvm-svn: 200033
These transformations obviously won't work for indexed (pre/post-inc) loads and
stores. In practice, I'm not sure there is any benefit to enabling them for
indexed nodes because other transformations that these might enable likely also
won't handle indexed nodes.
I don't have an in-tree test case that hits this problem, but an upcoming bug
fix will make it much more likely.
llvm-svn: 200023
This pass identifies expensive constants to hoist and coalesces them to
better prepare it for SelectionDAG-based code generation. This works around the
limitations of the basic-block-at-a-time approach.
First it scans all instructions for integer constants and calculates its
cost. If the constant can be folded into the instruction (the cost is
TCC_Free) or the cost is just a simple operation (TCC_BASIC), then we don't
consider it expensive and leave it alone. This is the default behavior and
the default implementation of getIntImmCost will always return TCC_Free.
If the cost is more than TCC_BASIC, then the integer constant can't be folded
into the instruction and it might be beneficial to hoist the constant.
Similar constants are coalesced to reduce register pressure and
materialization code.
When a constant is hoisted, it is also hidden behind a bitcast to force it to
be live-out of the basic block. Otherwise the constant would be just
duplicated and each basic block would have its own copy in the SelectionDAG.
The SelectionDAG recognizes such constants as opaque and doesn't perform
certain transformations on them, which would create a new expensive constant.
This optimization is only applied to integer constants in instructions and
simple (this means not nested) constant cast experessions. For example:
%0 = load i64* inttoptr (i64 big_constant to i64*)
Reviewed by Eric
llvm-svn: 200022
There is no inline asm in a .s file. Therefore, there should be no logic to
handle it in the streamer. Inline asm only exists in bitcode files, so the
logic can live in the (long misnamed) AsmPrinter class.
llvm-svn: 200011
compile unit. Make these relocations on the platforms that need
relocations and add a routine to ensure that we don't put the
addresses in an offset table for split dwarf.
llvm-svn: 199990
This patch adds the target analysis passes (usually TargetTransformInfo) to the
codgen pipeline. We also expose now the AddAnalysisPasses method through the C
API, because the optimizer passes would also benefit from better target-specific
cost models.
Reviewed by Andrew Kaylor
llvm-svn: 199926
e.g. linkonce, to TargetMachine and set it when we've done so
for ELF targets currently. This involved making TargetMachine
non-const in a TLOF use and propagating that change around - I'm
open to other ideas.
This will be used in a future commit to handle emitting debug
information with ranges.
llvm-svn: 199871
This is a horrible bit of code. We're calling a simplification routine *in the middle* of type legalization. We tell the
simplification routine that it's running after legalization, but some of the types it will encounter will be illegal! The
fix is only to invoke the simplification if the types in question were legal, so that none of its invariants will be violated.
llvm-svn: 199847
This patch restores the ARM mode if the user's inline assembly
does not. In the object streamer, it ensures that instructions
following the inline assembly are encoded correctly and that
correct mapping symbols are emitted. For the asm streamer, it
emits a .arm or .thumb directive.
This patch does not ensure that the inline assembly contains
the ADR instruction to switch modes at runtime.
The problem we need to solve is code like this:
int foo(int a, int b) {
int r = a + b;
asm volatile(
".align 2 \n"
".arm \n"
"add r0,r0,r0 \n"
: : "r"(r));
return r+1;
}
If we compile this function in thumb mode then the inline assembly
will switch to arm mode. We need to make sure that we switch back to
thumb mode after emitting the inline assembly or we will incorrectly
encode the instructions that follow (i.e. the assembly instructions
for return r+1).
Based on patch by David Peixotto
Change-Id: Ib57f6d2d78a22afad5de8693fba6230ff56ba48b
llvm-svn: 199818
This actually totally breaks and causes the machine verifier to cry in several cases, one of which being:
%RAX<def> = COPY %RCX<kill>
%ECX<def> = COPY %EAX<kill>, %RAX<imp-use,kill>
These subregister copies are together identified as noops, so are both removed. However, the second one as it has an imp-use gets converted into a kill:
%ECX<def> = KILL %EAX<kill>, %RAX<imp-use,kill>
As the original COPY has been removed, the verifier goes into tears at the use of undefined EAX and RAX.
There are several hacky solutions to this hacky problem (which is all to do with imp-use/def weirdnesses), but the least hacky I've come up with is to *always* remove COPYs by converting to KILLs. KILLs are no-ops to the code generator so the generated code doesn't change (which is why they were partially used in the first place), but using them also keeps the def/use and imp-def/imp-use chains alive:
%RAX<def> = KILL %RCX<kill>
%ECX<def> = KILL %EAX<kill>, %RAX<imp-use,kill>
The patch passes all test cases including the ones that check the removal of MOVs in this circumstance, along with an extra test I added to check subregister behaviour (which made the machine verifier fall over before my patch).
The patch also adds some DEBUG() statements because the file hadn't got any.
llvm-svn: 199797
Fix a crash in SjLjEHPrepare::lowerIncomingArguments caused by treating
VectorType like an aggregate. It's first-class!
<rdar://problem/15854596>
llvm-svn: 199768
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
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
type units were enabled. The crux of the issue is that the
addDwarfTypeUnitType routine can end up being indirectly recursive. In
this case, the reference into the dense map (TU) became invalid by the
time we popped all the way back and used it to add the DIE type
signature.
Instead, use early return in the case where we can bypass the recursive
step and creating a type unit. Then use the pointer to the new type unit
to set up the DIE type signature in the case where we have to.
I tried really hard to reduce a testcase for this, but it's really
annoying. You have to get this to be mid-recursion when the densemap
grows. Even if we got a test case for this today, it'd be very unlikely
to continue exercising this pattern.
llvm-svn: 199630
Eric Christopher