David Blaikie [Sun, 5 Apr 2015 22:41:44 +0000 (22:41 +0000)]
[opaque pointer type] The last of the GEP IRBuilder API migrations
There's still lots of callers passing nullptr, of course - some because
they'll never be migrated (InstCombines for bitcasts - well they don't
make any sense when the pointer type is opaque anyway, for example) and
others that will need more engineering to pass Types around.
This allows the compiler/assembly programmer to switch back to a
section. This in turn fixes the bootstrap failure on powerpc (tested
on gcc110) without changing the ppc codegen at all.
I will try to cleanup the various getELFSection overloads in a followup patch.
Just using a default argument now would lead to ambiguities.
[X86] Don't use GR64 register 'and with immediate' instructions if the immediate is zero in the upper 33-bits or upper 57-bits. Use GR32 instructions instead.
Previously the patterns didn't have high enough priority and we would only use the GR32 form if the only the upper 32 or 56 bits were zero.
David Majnemer [Fri, 3 Apr 2015 22:32:26 +0000 (22:32 +0000)]
[WinEH] Sink UnwindHelp completely out of IR
We don't need to represent UnwindHelp in IR. Instead, we can use the
knowledge that we are emitting the parent function to decide if we
should create the UnwindHelp stack object.
David Blaikie [Fri, 3 Apr 2015 19:41:44 +0000 (19:41 +0000)]
[opaque pointer type] More GEP API migrations in IRBuilder uses
The plan here is to push the API changes out from the common components
(like Constant::getGetElementPtr and IRBuilder::CreateGEP related
functions) and just update callers to either pass the type if it's
obvious, or pass null.
Do this with LoadInst as well and anything else that comes up, then to
start porting specific uses to not pass null anymore - this may require
some refactoring in each case.
As a follow-up to r234021, assert that a debug info intrinsic variable's
`MDLocalVariable::getInlinedAt()` always matches the
`MDLocation::getInlinedAt()` of its `!dbg` attachment.
The goal here is to get rid of `MDLocalVariable::getInlinedAt()`
entirely (PR22778), but I'll let these assertions bake for a while
first.
If you have an out-of-tree backend that just broke, you're probably
attaching the wrong `DebugLoc` to a `DBG_VALUE` instruction. The one
you want is the location that was attached to the corresponding
`@llvm.dbg.declare` or `@llvm.dbg.value` call that you started with.
[GraphWriter] Attempt to open .dot files with xdg-open/open first
Most desktop environments let the users specify his preferred application per
file type. On mac/linux we can use open/xdg-open for that and should try this
first before starting a heuristic search for various programs.
Check that the `MDLocalVariable::getInlinedAt()` in a debug info
intrinsic's variable always matches the `MDLocation::getInlinedAt()` of
its `!dbg` attachment.
The goal here is to get rid of `MDLocalVariable::getInlinedAt()`
entirely (PR22778), since it's expensive and unnecessary, but I'll let
this verifier check bake for a while (a week maybe?) first. I've
updated the testcases that had the wrong value for `inlinedAt:`.
This checks that things are sane in the IR, but currently things go out
of whack in a few places in the backend. I'll follow shortly with
assertions in the backend (with code fixes).
If you have out-of-tree testcases that just started failing, here's how
I updated these ones:
1. The verifier check gives you the basic block, function, instruction,
and relevant metadata arguments (metadata numbering doesn't
necessarily match the source file, unfortunately).
2. Look at the `@llvm.dbg.*()` instruction, and compare the
`inlinedAt:` fields of the variable argument (second `metadata`
argument) and the `!dbg` attachment.
3. Figure out based on the variable `scope:` chain and the functions in
the file whether the variable has been inlined (and into what), so
you can determine which `inlinedAt:` is actually correct. In all of
the in-tree testcases, the `!MDLocation()` was correct and the
`!MDLocalVariable()` was wrong, but YMMV.
4. Duplicate the metadata that you're going to change, and add/drop the
`inlinedAt:` field from one of them. Be careful that the other
references to the same metadata node point at the correct one.
Bill Schmidt [Fri, 3 Apr 2015 13:48:24 +0000 (13:48 +0000)]
[PowerPC] Enable splat generation for BUILD_VECTOR with little endian
When enabling PPC64LE, I disabled some optimizations of BUILD_VECTOR
nodes for little endian because wrong results were produced. I've
subsequently investigated and found this is due to a call to
BuildVectorSDNode::isConstantSplat that was always specifying
big-endian. With this changed to correctly identify the target
endianness, the optimizations work as expected.
I found another case of a call to the same method with big-endian
hardcoded, in PPC::isAllNegativeZeroVector(). I discovered this was
an orphaned method with no callers, so I've just removed it.
The existing test/CodeGen/PowerPC/vec_constants.ll checks these
optimizations, so for testing I've just added a variant for little
endian.
Simon Pilgrim [Fri, 3 Apr 2015 10:02:21 +0000 (10:02 +0000)]
[DAGCombiner] Combine shuffles of BUILD_VECTOR and SCALAR_TO_VECTOR
This patch attempts to fold the shuffling of 'scalar source' inputs - BUILD_VECTOR and SCALAR_TO_VECTOR nodes - if the shuffle node is the only user. This folds away a lot of unnecessary shuffle nodes, and allows quite a bit of constant folding that was being missed.
MC: For variable symbols, maintain MCSymbol::Section as a cache.
Fixes PR19582.
Previously, when an asm assignment (.set or =) was created, we would look up
the section immediately in MCSymbol::setVariableValue. This caused symbols
to receive the wrong section if the RHS of the assignment had not been seen
yet. This had a knock-on effect in the object file emitters, causing them
to emit extra symbols, or to give symbols the wrong visibility or the wrong
section. For example, in the following asm:
the first assignment would give .Llocal1 a null section, which would never get
fixed up by the second assignment. This would cause the ELF object file emitter
to consider .Llocal1 to be an undefined symbol and give it external linkage,
even though .Llocal1 should not have been emitted at all in the object file.
Or in the following asm:
alias_to_local = Ltmp0
Ltmp0:
the Mach-O object file emitter would give the alias_to_local symbol a n_type
of N_SECT and a n_sect of 0. This is invalid under the Mach-O specification,
which requires N_SECT symbols to receive a non-zero section number if the
symbol is defined in a section in the object file.
After this change we do not look up the section when the assignment is created,
but instead look it up on demand and store it in Section, which is treated
as a cache if the symbol is a variable symbol.
This change also fixes a bug in MCExpr::FindAssociatedSection. Previously,
if we saw a subtraction, we would return the first referenced section, even in
cases where we should have been returning the absolute pseudo-section. Now we
always return the absolute pseudo-section for expressions that subtract two
section-derived expressions. This isn't always correct (e.g. if one of the
sections ends up being laid out at an absolute address), but it's probably
the best we can do without more context.
This allows us to remove code in two places where we appear to have been
working around this bug, in MachObjectWriter::markAbsoluteVariableSymbols
and in X86AsmPrinter::EmitStartOfAsmFile.
Re-applies r233595 (aka D8586), which was reverted in r233898.
ARM: Handle physreg targets in RegPair hints gracefully
Register coalescing can change the target of a RegPair hint to a
physreg, we should not crash on this. This also slightly improved the
way ARMBaseRegisterInfo::updateRegAllocHint() works.
[ASan] Don't use stack malloc for 32-bit functions using inline asm
This prevents us from running out of registers in the backend.
Introducing stack malloc calls prevents the backend from recognizing the
inline asm operands as stack objects. When the backend recognizes a
stack object, it doesn't need to materialize the address of the memory
in a physical register. Instead it generates a simple SP-based memory
operand. Introducing a stack malloc forces the backend to find a free
register for every memory operand. 32-bit x86 simply doesn't have enough
registers for this to succeed in most cases.
[WinEH] Make llvm.eh.actions use frameescape indices for catch params
This makes it possible to use the same representation of llvm.eh.actions
in outlined handlers as we use in the parent function because i32's are
just constants that can be copied freely between functions.
I had to add a sentinel alloca to the list of child allocas so that we
don't try to sink the catch object into the handler. Normally, one would
use nullptr for this kind of thing, but TinyPtrVector doesn't support
null elements. More than that, it's elements have to have a suitable
alignment. Therefore, I settled on this for my sentinel:
[AVX] Improve insertion of i8 or i16 into low element of 256-bit zero vector
Without this patch, we split the 256-bit vector into halves and produced something like:
movzwl (%rdi), %eax
vmovd %eax, %xmm0
vxorps %xmm1, %xmm1, %xmm1
vblendps $15, %ymm0, %ymm1, %ymm0 ## ymm0 = ymm0[0,1,2,3],ymm1[4,5,6,7]
Now, we eliminate the xor and blend because those zeros are free with the vmovd:
movzwl (%rdi), %eax
vmovd %eax, %xmm0
This should be the final fix needed to resolve PR22685:
https://llvm.org/bugs/show_bug.cgi?id=22685
David Blaikie [Thu, 2 Apr 2015 18:55:32 +0000 (18:55 +0000)]
[opaque pointer type] API migration for GEP constant factories
Require the pointee type to be passed explicitly and assert that it is
correct. For now it's possible to pass nullptr here (and I've done so in
a few places in this patch) but eventually that will be disallowed once
all clients have been updated or removed. It'll be a long road to get
all the way there... but if you have the cahnce to update your callers
to pass the type explicitly without depending on a pointer's element
type, that would be a good thing to do soon and a necessary thing to do
eventually.
We're generating a blend when a move scalar does the same job using 2 less instruction bytes (see FIXMEs).
We're not matching an existing pattern that would eliminate the xor and blend entirely. The zero bytes are free with vmovd.
The 2nd fix involves an adjustment of "AddedComplexity" [1] and mostly masks the 1st problem.
[1] AddedComplexity has close to no documentation in the source.
The best we have is this comment: "roughly corresponds to the number of nodes that are covered".
It appears that x86 has bastardized this definition by inflating its values for some other
undocumented reason. For example, we have a pattern with "AddedComplexity = 400" (!).
I searched my way to this page:
https://groups.google.com/forum/#!topic/llvm-dev/5UX-Og9M0xQ
Add an LLVM_PTR_SIZE macro to make LLVM_ALIGNAS more useful
MSVC 2013 requires the argument to __declspec(align()) to be an integer
constant expression that doesn't involve any identifiers like sizeof.
For GCC and Clang, LLVM_PTR_SIZE is equivalent to __SIZEOF_POINTER__,
which dates back to GCC 4.6 and Clang 2010. If that's not available, we
get sizeof(void*), which works with alignas() and
__attribute__((aligned())).
For MSVC, LLVM_PTR_SIZE is 4 or 8 depending on _WIN64.
Benjamin Kramer [Thu, 2 Apr 2015 13:31:50 +0000 (13:31 +0000)]
[alignof] Put back the hack for old versions of GCC.
This works around a bug (PR56859) that is fixed in all versions of GCC I tested
with but was present in 4.8.0. Using 4.8.0 is of course a terrible idea, but looks
like we can't drop it just yet.
[mips] Implement eliminateCallFramePseudoInstr() in MipsFrameLowering. NFC.
Summary:
Avoid duplicate code in Mips16FrameLowering and MipsSEFrameLowering by
providing an implementation of the eliminateCallFramePseudoInstr()
function from their base class.
[mips] Expose adjustStackPtr() from MipsInstrInfo. NFC.
Summary:
adjustStackPtr() is implemented from both MipsSEInstrInfo and
Mips16InstrInfo. It makes sense to expose this function from
MipsInstrInfo and avoid explicit casting in some cases.
Philip Reames [Thu, 2 Apr 2015 05:00:40 +0000 (05:00 +0000)]
Teach gcroot how to handle dynamically realigned frames
I'm playing with supporting custom stack map formats with statepoints. While
doing so, I noticed that the existing implementation didn't indicate inherently
unsized frames. This change essentially just ports the functionality that already
exists for the default StackMaps section to custom stackmaps.
Lang Hames [Thu, 2 Apr 2015 04:34:45 +0000 (04:34 +0000)]
[Orc] Add support classes for inspecting and running C++ static ctor/dtors, and
use these to add support for C++ static ctors/dtors to the Orc-lazy JIT in LLI.
Replace the trivial_retval_1 regression test - the new 'hello' test is covering
strictly more code.
Kevin Enderby [Wed, 1 Apr 2015 20:57:01 +0000 (20:57 +0000)]
Add the option -objc-meta-data to llvm-objdump used with -macho to
print the Objective-C runtime meta data for Mach-O files.
There are three types of Objective-C runtime meta data, Objc2 64-bit,
Objc2 32-bit and Objc1 32-bit. This prints the first of these types. The
changes to print the others will follow next.
Sanjoy Das [Wed, 1 Apr 2015 18:24:06 +0000 (18:24 +0000)]
[SCEV] Look at backedge dominating conditions (re-land r233447).
Summary:
This change teaches ScalarEvolution::isLoopBackedgeGuardedByCond to look
at edges within the loop body that dominate the latch. We don't do an
exhaustive search for all possible edges, but only a quick walk up the
dom tree.
This re-lands r233447. r233447 was reverted because it caused massive
compile-time regressions. This change has a fix for the same issue.
Diego Novillo [Wed, 1 Apr 2015 17:42:27 +0000 (17:42 +0000)]
Remove 4,096 loop scale limitation.
Summary:
This is part 1 of fixes to address the problems described in
https://llvm.org/bugs/show_bug.cgi?id=22719.
The restriction to limit loop scales to 4,096 does not really prevent
overflows anymore, as the underlying algorithm has changed and does
not seem to suffer from this problem.
Additionally, artificially restricting loop scales to such a low number
skews frequency information, making loops of equal hotness appear to
have very different hotness properties.
The only loops that are artificially restricted to a scale of 4096 are
infinite loops (those loops with an exit mass of 0). This prevents
infinite loops from skewing the frequencies of other regions in the CFG.
At the end of propagation, frequencies are scaled to values that take no
more than 64 bits to represent. When the range of frequencies to be
represented fits within 61 bits, it pushes up the scaling factor to a
minimum of 8 to better distinguish small frequency values. Otherwise,
small frequency values are all saturated down at 1.