Jozef Kolek [Fri, 21 Nov 2014 22:04:35 +0000 (22:04 +0000)]
[mips][microMIPS] This patch implements functionality in MIPS delay slot
filler such as if delay slot filler have to put NOP instruction into the
delay slot of microMIPS BEQ or BNE instruction which uses the register $0,
then instead of emitting NOP this instruction is replaced by the corresponding
microMIPS compact branch instruction, i.e. BEQZC or BNEZC.
Tim Northover [Fri, 21 Nov 2014 20:16:09 +0000 (20:16 +0000)]
Remove duplication of relocation names in lib/Object/ELFYAML.cpp
We can now use the ELF relocation .def files to create the mapping
of relocation numbers to names and avoid having to duplicate the
list of relocations.
Tim Northover [Fri, 21 Nov 2014 20:16:07 +0000 (20:16 +0000)]
Remove duplication of relocation names in lib/Object/ELF.cpp
We can now use the ELF relocation .def files to create the mapping
of relocation numbers to names and avoid having to duplicate the
list of relocations.
Tim Northover [Fri, 21 Nov 2014 20:16:02 +0000 (20:16 +0000)]
Split ELF relocation defintions into per-architecture .def files
This should allow the list of relocations for a particular
architecture to be kept in a single header rather than duplicated
whenever we need to enumerate all the relocations.
Sanjay Patel [Fri, 21 Nov 2014 17:40:04 +0000 (17:40 +0000)]
Add a feature flag for slow 32-byte unaligned memory accesses [x86].
This patch adds a feature flag to avoid unaligned 32-byte load/store AVX codegen
for Sandy Bridge and Ivy Bridge. There is no functionality change intended for
those chips. Previously, the absence of AVX2 was being used as a proxy to detect
this feature. But that hindered codegen for AVX-enabled AMD chips such as btver2
that do not have the 32-byte unaligned access slowdown.
Performance measurements are included in PR21541 ( http://llvm.org/bugs/show_bug.cgi?id=21541 ).
Revert "Allow FDE references outside the +/-2GB range supported by PC relative offsets for code models other than small/medium. For JIT application, memory layout is less controlled and can result in truncations otherwise."
This reverts commit r222538.
It's causing test failures for CFI, at least on Darwin:
Note that the previous incremental build was on r222537, and the CFI
tests weren't failing:
http://lab.llvm.org:8080/green/job/clang-stage1-cmake-RA-incremental/1188/
Chandler Carruth [Fri, 21 Nov 2014 14:53:03 +0000 (14:53 +0000)]
[x86] Restructure the checking patterns for v16 and v32 avx2 vector
shuffle lowering to allow much better blend matching.
Specifically, with the new structure the code seems clearer to me and we
correctly can hit the cases where merging two 128-bit lanes is a clear
win and can be shuffled cheaply afterward.
Allow FDE references outside the +/-2GB range supported by PC relative
offsets for code models other than small/medium. For JIT application,
memory layout is less controlled and can result in truncations
otherwise.
Chandler Carruth [Fri, 21 Nov 2014 14:33:24 +0000 (14:33 +0000)]
[x86] Make the previous logic significantly less conservative and get
a bunch more improvements.
Non-lane-crossing is fine, the key is that lane merging only makes sense
for single-input shuffles. Not sure why I got so turned around here. The
code all works, I was just using the wrong model for it.
This only updates v4 and v8 lowering. The v16 and v32 lowering requires
restructuring the entire check sequence.
Andrea Di Biagio [Fri, 21 Nov 2014 14:32:06 +0000 (14:32 +0000)]
[DAG] Teach how to turn a build_vector into a shuffle if some of the operands are zero.
Before this patch, the DAGCombiner only tried to convert build_vector dag nodes
into shuffles if all operands were either extract_vector_elt or undef.
This patch improves that logic and teaches the DAGCombiner how to deal with
build_vector dag nodes where one or more operands are zero. A build_vector
dag node with some zero operands is turned into a shuffle only if the resulting
shuffle mask is legal for the target.
Chandler Carruth [Fri, 21 Nov 2014 13:56:05 +0000 (13:56 +0000)]
[x86] Teach the x86 vector shuffle lowering to detect mergable 128-bit
lanes.
By special casing these we can often either reduce the total number of
shuffles significantly or reduce the number of (high latency on Haswell)
AVX2 shuffles that potentially cross 128-bit lanes. Even when these
don't actually cross lanes, they have much higher latency to support
that. Doing two of them and a blend is worse than doing a single insert
across the 128-bit lanes to blend and then doing a single interleaved
shuffle.
While this seems like a narrow case, it kept cropping up on me and the
difference is *huge* as you can see in many of the test cases. I first
hit this trying to perfectly fix the interleaving shuffle patterns used
by Halide for AVX2.
Chandler Carruth [Fri, 21 Nov 2014 12:17:50 +0000 (12:17 +0000)]
[x86] Add a bunch of test cases to 256-bit shuffles that exercise
merging 128-bit subvectors and also shuffling all the elements of those
subvectors. Currently we generate pretty bad code for many of these, but
I'm testing a patch that should dramatically improve this in addition to
making the shuffle lowering robust to other changes.
Andrea Di Biagio [Fri, 21 Nov 2014 11:33:07 +0000 (11:33 +0000)]
[DAG] Refactor the shuffle combining logic in DAGCombiner. NFC.
This patch simplifies the logic that combines a pair of shuffle nodes into
a single shuffle if there is a legal mask. Also added comments to better
describe the algorithm. No functional change intended.
Hao Liu [Fri, 21 Nov 2014 06:39:58 +0000 (06:39 +0000)]
DAGCombiner: Allow the DAGCombiner to combine multiple FDIVs with the same divisor info FMULs by the reciprocal.
E.g., ( a / D; b / D ) -> ( recip = 1.0 / D; a * recip; b * recip)
A hook is added to allow the target to control whether it needs to do such combine.
Hal Finkel [Fri, 21 Nov 2014 04:35:51 +0000 (04:35 +0000)]
[PPC] Use SeparateConstOffsetFromGEP
This mirrors r222331, which enabled SeparateConstOffsetFromGEP on AArch64, in
the PowerPC backend. Yields, on a POWER7 machine, a 30% speedup on
SingleSource/Benchmarks/Shootout/nestedloop (this might just be from LICM,
there is a store moved out of the inner loop) and a potential speedup on
MultiSource/Benchmarks/mediabench/mpeg2/mpeg2dec/mpeg2decode. Regardless, it
makes some code look cleaner, and synchronizing the backends in this regard
seems like a generally good thing.
Hal Finkel [Fri, 21 Nov 2014 02:22:46 +0000 (02:22 +0000)]
Clarify the description of the noalias attribute
The previous description of the noalias attribute did not accurately specify
the implemented semantics, and the terminology used differed unnecessarily
from that used by the C specification to define the semantics of restrict. For
the argument attribute, the semantics can be precisely specified in terms of
objects accessed through pointers based on the arguments, and this is now what
is done.
Saying that the semantics are 'slightly weaker' than that provided by C99
restrict is not really useful without further elaboration, so that has been
removed from the sentence.
noalias on a return value is really used to mean that the function is
malloc-like (and, in fact, we use this attribute to represent
__attribute__((malloc)) in Clang), and this is a stronger guarantee than that
provided by restrict (because it is a property of the pointed-to memory region,
not just a guarantee on object access). Clarifying this is relevant to fixing
(and was motivated by the discussion on) PR21556.
Adrian Prantl [Fri, 21 Nov 2014 00:39:43 +0000 (00:39 +0000)]
Verifier: Check that all instructions have their parent pointers set up
correctly. This helps with catching problems caused by IRBuilder abuse
such as the one fixed in CFE r222487.
Reid Kleckner [Thu, 20 Nov 2014 23:37:18 +0000 (23:37 +0000)]
Add out of line virtual destructors to all LLVMTargetMachine subclasses
These recently all grew a unique_ptr<TargetLoweringObjectFile> member in
r221878. When anyone calls a virtual method of a class, clang-cl
requires all virtual methods to be semantically valid. This includes the
implicit virtual destructor, which triggers instantiation of the
unique_ptr destructor, which fails because the type being deleted is
incomplete.
This is just part of the ongoing saga of PR20337, which is affecting
Blink as well. Because the MSVC ABI doesn't have key functions, we end
up referencing the vtable and implicit destructor on any virtual call
through a class. We don't actually end up emitting the dtor, so it'd be
good if we could avoid this unneeded type completion work.
Mehdi Amini [Thu, 20 Nov 2014 22:40:25 +0000 (22:40 +0000)]
SimplifyCFG: Refactor GatherConstantCompares() result in a struct
Code seems cleaner and easier to understand this way
This is basically r222416, after fixes for MSVC lack of standard
support, and a few cleaning (got rid of a warning).
Thanks Nakamura Takumi and Nico Weber for the MSVC fixes.
Currently LoopUnroll generates a prologue loop before the main loop
body to execute first N%UnrollFactor iterations. Also, this loop is
used if trip-count can overflow - it's determined by a runtime check.
However, we've been mistakenly optimizing this loop to a linear code for
UnrollFactor = 2, not taking into account that it also serves as a safe
version of the loop if its trip-count overflows.
Michael Ilseman [Thu, 20 Nov 2014 19:33:33 +0000 (19:33 +0000)]
Compilation test for PostOrderIterator.
If the template specialization for externally managed sets in
PostOrderIterator call too far out of sync with each other, this unit
test will fail to build. This is especially useful for developers who
may not build Clang (the only in-tree user) every time.
Michael Ilseman [Thu, 20 Nov 2014 19:33:30 +0000 (19:33 +0000)]
Update template specialization to reflect API changes.
po_iterator_storage's insertEdge was updated to reflect the API
changes from many of our insert methods in r222334, however the
template specialization for external storage was not updated. This
updates the specialization.
X86: use the correct alloca symbol for Windows Itanium
Windows itanium targets the MSVCRT, and the stack probe symbol is provided by
MSVCRT. This corrects the emission of stack probes on i686-windows-itanium.
Frederic Riss [Thu, 20 Nov 2014 15:52:34 +0000 (15:52 +0000)]
Do not create a replaceable Variables MDNode for function forward decls.
These fields would need to be explicitly deleted before we RAUW the temporary
node anyway (this was done in cfe commit r222373). Instead, do not create
these useless nodes in the first place.
Alexey Samsonov [Thu, 20 Nov 2014 01:27:19 +0000 (01:27 +0000)]
Remove support for undocumented SpecialCaseList entries.
"global-init", "global-init-src" and "global-init-type" were originally
used to blacklist entities in ASan init-order checker. However, they
were never documented, and later were replaced by "=init" category.
Old blacklist entries should be converted as follows:
* global-init:foo -> global:foo=init
* global-init-src:bar -> src:bar=init
* global-init-type:baz -> type:baz=init
Matthias Braun [Wed, 19 Nov 2014 19:46:17 +0000 (19:46 +0000)]
RegisterCoalescer: Improve debug messages
- Show "Considering..." message after flipping so you actually see the final
destination vreg as destination.
- Add a message on final join, so you can grep for "Success" messages to obtain
a list of which register got merged with which.
Andrea Di Biagio [Wed, 19 Nov 2014 19:34:29 +0000 (19:34 +0000)]
[X86] Improved lowering of v4x32 build_vector dag nodes.
This patch improves the lowering of v4f32 and v4i32 build_vector dag nodes
that are known to have at least two non-zero elements.
With this patch, a build_vector that performs a blend with zero is
converted into a shuffle. This is done to let the shuffle legalizer expand
the dag node in a optimal way. For example, if we know that a build_vector
performs a blend with zero, we can try to lower it as a movq/blend instead of
always selecting an insertps.
This patch also improves the logic that lowers a build_vector into a insertps
with zero masking. See for example the extra test cases added to test sse41.ll.
Lang Hames [Wed, 19 Nov 2014 19:15:41 +0000 (19:15 +0000)]
[ADT] Fix PR20728 - Incorrect APFloat::fusedMultiplyAdd results for x86_fp80.
As detailed at http://llvm.org/PR20728, due to an internal overflow in
APFloat::multiplySignificand the APFloat::fusedMultiplyAdd method can return
incorrect results for x87DoubleExtended (x86_fp80) values. This commonly
manifests as incorrect constant folding of libm fmal calls on x86. E.g.
fmal(1.0L, 1.0L, 3.0L) == 0.0L (should be 4.0L)
This patch fixes PR20728 by adding an extra bit to the significand for
intermediate results of APFloat::multiplySignificand, avoiding the overflow.
Tom Stellard [Wed, 19 Nov 2014 16:58:49 +0000 (16:58 +0000)]
R600/SI: Make SIInstrInfo::isOperandLegal() more strict
A register operand that has a common sub-class with its instruction's
defined register class is not always legal. For example,
SReg_32 and M0Reg both have a common sub-class, but we can't
use an SReg_32 in instructions that expect a M0Reg.
This prevents the llvm.SI.sendmsg.ll test from failing when the fold
operand pass is added.