Fix a compact unwind encoding logic bug which would try to encode
more callee saved registers than it should, leading to early bail out
in the encoding logic and abusive use of DWARF frame mode unnecessarily.
Also remove no-compact-unwind.ll which was testing the wrong thing
based on this bug and move it to valid 'compact unwind' tests. Added
other few more tests too.
Justin Bogner [Mon, 8 Dec 2014 18:02:35 +0000 (18:02 +0000)]
InstrProf: An intrinsic and lowering for instrumentation based profiling
Introduce the ``llvm.instrprof_increment`` intrinsic and the
``-instrprof`` pass. These provide the infrastructure for writing
counters for profiling, as in clang's ``-fprofile-instr-generate``.
The implementation of the instrprof pass is ported directly out of the
CodeGenPGO classes in clang, and with the followup in clang that rips
that code out to use these new intrinsics this ends up being NFC.
Doing the instrumentation this way opens some doors in terms of
improving the counter performance. For example, this will make it
simple to experiment with alternate lowering strategies, and allows us
to try handling profiling specially in some optimizations if we want
to.
Finally, this drastically simplifies the frontend and puts all of the
lowering logic in one place.
[X86] Improved tablegen patters for matching TZCNT/LZCNT.
Teach ISel how to match a TZCNT/LZCNT from a conditional move if the
condition code is X86_COND_NE.
Existing tablegen patterns only allowed to match TZCNT/LZCNT from a
X86cond with condition code equal to X86_COND_E. To avoid introducing
extra rules, I added an 'ImmLeaf' definition that checks if the
condition code is COND_E or COND_NE.
[X86] Improved lowering of packed v8i16 vector shifts by non-constant count.
Before this patch, the backend sub-optimally expanded the non-constant shift
count of a v8i16 shift into a sequence of two 'movd' plus 'movzwl'.
With this patch the backend checks if the target features sse4.1. If so, then
it lets the shuffle legalizer deal with the expansion of the shift amount.
Example:
;;
define <8 x i16> @test(<8 x i16> %A, <8 x i16> %B) {
%shamt = shufflevector <8 x i16> %B, <8 x i16> undef, <8 x i32> zeroinitializer
%shl = shl <8 x i16> %A, %shamt
ret <8 x i16> %shl
}
;;
X86 intrinsics moved form X86ISelLowering.cpp to X86IntrinsicsInfo.h
X86ISelLowering.cpp has a long switch for intrinsics. I moved a part of
this long switch to the new intrinsics table in X86IntrinsicsInfo.h.
No functional changes, just code and compile time optimization.
IR: Revert r223618 behaviour of MDNode::concatenate()
r223618 including special handling of `MDNode::intersect()`: if the
first operand is a self-reference with the same operands you're trying
to return, return it instead.
Reuse that handling in `MDNode::concatenate()` in the hopes that it
fixes a polly test that seems to rely on the old behaviour [1].
It doesn't make sense to unique self-referencing nodes. Drop uniquing
for them.
Note that `MDNode::intersect()` occasionally returns self-referencing
nodes. Previously these would be returned by `MDNode::get()`. I'm not
convinced this was intended behaviour -- to me it seems it should return
a node whose only operand is the self-reference -- but I don't know much
about alias scopes so I'm preserving it for now.
Apparently `MDNode` uniquing used to be optional. I suppose the
configure flag must have disappeared at some point. Change the test so
it actually tests uniquing, and remove the check for
`ENABLE_MDNODE_UNIQUING`.
Add assembly and bitcode tests that I neglected to add in r223564 (IR:
Disallow complicated function-local metadata) and r223574 (IR: Disallow
function-local metadata attachments).
Found a couple of bugs:
- The error message for function-local attachments gave the wrong line
number -- it indicated the next token (typically on the next line)
instead of the token that started the attachment. Fixed.
- Metadata arguments of the form `!{i32 0, i32 %v}` (or with the
arguments reversed) fired an assertion in `ValueEnumerator` in LLVM
v3.5, so I suppose this never really worked. I suppose this was
"fixed" by r223564.
(Thanks to dblaikie for pointing out my omission.)
[x86] Clean up the SSE1 test to use a slightly different pattern for
matching offsets. I don't expect this to really matter, but its what the
latest incarnation of my script for maintaining these tests happens to
produce, and so its simpler for me if everything matches.
[x86] Switch a constant selection test to use positive assertions and to
store to real pointers so that its clear that the right code is in fact
being generated.
[x86] Clean up the shift lowering vector shuffle tests a bit using my
script. Notably this folds all the SSE cases together into a single
FileCheck block. It also adds a vex prefix.
Benjamin Kramer [Sat, 6 Dec 2014 19:22:44 +0000 (19:22 +0000)]
Make the DenseMap bucket type configurable and use a smaller bucket for DenseSet.
DenseSet used to be implemented as DenseMap<Key, char>, which usually doubled
the memory footprint of the map. Now we use a compressed set so the second
element uses no memory at all. This required some surgery on DenseMap as
all accesses to the bucket now have to go through methods; this should
have no impact on the behavior of DenseMap though. The new default bucket
type for DenseMap is a slightly extended std::pair as we expose it through
DenseMap's iterator and don't want to break any existing users.
Hans Wennborg [Sat, 6 Dec 2014 01:28:50 +0000 (01:28 +0000)]
SelectionDAG switch lowering: Replace unreachable default with most popular case.
This can significantly reduce the size of the switch, allowing for more
efficient lowering.
I also worked with the idea of exploiting unreachable defaults by
omitting the range check for jump tables, but always ended up with a
non-neglible binary size increase. It might be worth looking into some more.
SimplifyCFG currently does this transformation, but I'm working towards changing
that so we can optimize harder based on unreachable defaults.
Disallow complex types of function-local metadata. The only valid
function-local metadata is an `MDNode` whose sole argument is a
non-metadata function-local value.
Sanjay Patel [Fri, 5 Dec 2014 21:28:14 +0000 (21:28 +0000)]
Optimize merging of scalar loads for 32-byte vectors [X86, AVX]
Fix the poor codegen seen in PR21710 ( http://llvm.org/bugs/show_bug.cgi?id=21710 ).
Before we crack 32-byte build vectors into smaller chunks (and then subsequently
glue them back together), we should look for the easy case where we can just load
all elements in a single op.
Jan Wen Voung [Fri, 5 Dec 2014 20:55:53 +0000 (20:55 +0000)]
Use 32-bit ebp for NaCl64 in a limited case: llvm.frameaddress.
Summary:
Follow up to [x32] "Use ebp/esp as frame and stack pointer":
http://reviews.llvm.org/D4617
In that earlier patch, NaCl64 was made to always use rbp.
That's needed for most cases because rbp should hold a full
64-bit address within the NaCl sandbox so that load/stores
off of rbp don't require sandbox adjustment (zeroing the top
32-bits, then filling those by adding r15).
However, llvm.frameaddress returns a pointer and pointers
are 32-bit for NaCl64. In this case, use ebp instead, which
will make the register copy type check. A similar mechanism
may be needed for llvm.eh.return, but is not added in this change.
[X86] Improved lowering of packed vector shifts to vpsllq/vpsrlq.
SSE2/AVX non-constant packed shift instructions only use the lower 64-bit of
the shift count.
This patch teaches function 'getTargetVShiftNode' how to deal with shifts
where the shift count node is of type MVT::i64.
Before this patch, function 'getTargetVShiftNode' only knew how to deal with
shift count nodes of type MVT::i32. This forced the backend to wrongly
truncate the shift count to MVT::i32, and then zero-extend it back to MVT::i64.
When a loop gets bundled up, its outgoing edges are quite large, and can
just barely overflow 64-bits. If one successor has multiple incoming
edges -- and that successor is getting all the incoming mass --
combining just its edges can overflow. Handle that by saturating rather
than asserting.
Benjamin Kramer [Fri, 5 Dec 2014 17:03:01 +0000 (17:03 +0000)]
LLVMContext: Store APInt/APFloat directly into the ConstantInt/FP DenseMaps.
Required some APInt massaging to get proper empty/tombstone values. Apart
from making the code a bit simpler this also reduces the bucket size of
the ConstantInt map from 32 to 24 bytes.