Zachary Turner [Mon, 27 Feb 2017 22:11:43 +0000 (22:11 +0000)]
[PDB] Partial resubmit of r296215, which improved PDB Stream Library.
This was reverted because it was breaking some builds, and
because of incorrect error code usage. Since the CL was
large and contained many different things, I'm resubmitting
it in pieces.
This portion is NFC, and consists of:
1) Renaming classes to follow a consistent naming convention.
2) Fixing the const-ness of the interface methods.
3) Adding detailed doxygen comments.
4) Fixing a few instances of passing `const BinaryStream& X`. These
are now passed as `BinaryStreamRef X`.
...starting in PerformADDCombineWithOperands(), but it wasn't actually checking for a setcc node
for the sext/zext patterns.
This is exactly the opposite of a transform I'd like to add to DAGCombiner's foldSelectOfConstants(),
so I was seeing infinite loops with my draft of a patch applied.
The changes in select_const.ll look positive (less instructions). The change in arm-and-tst-peephole.ll
is unrelated. We're changing the input IR in that test to preserve the intent of the test, but that's
not affected by this code change.
Lang Hames [Mon, 27 Feb 2017 21:09:47 +0000 (21:09 +0000)]
[Support][Error] Add a 'cantFail' utility function for known-safe calls to
fallible functions.
Some fallible functions (those returning Error or Expected<T>) may only fail
for a subset of their inputs. For example, a "safe" square root function will
succeed for all finite positive inputs:
At a safe callsite for such a function, checking the error return value is
redundant:
if (auto ValOrErr = safeSqrt(42.0)) {
// use *ValOrErr.
} else
llvm_unreachable("safeSqrt should always succeed for +ve values");
The cantFail function wraps this check and extracts the contained value,
simplifying control flow:
double Result = cantFail(safeSqrt(42.0));
This function should be used with care: it is a programmatic error to wrap a
call with cantFail if it can in fact fail. For debug builds this will
result in llvm_unreachable being called. For release builds the behavior is
undefined.
Use of this function is likely to be rare in library code, but more common
for tool and unit-test code where inputs and mock functions may be known to be
safe.
Simon Pilgrim [Mon, 27 Feb 2017 21:01:57 +0000 (21:01 +0000)]
[X86][SSE] Attempt to extract vector elements through target shuffles
DAGCombiner already supports peeking thorough shuffles to improve vector element extraction, but legalization often leaves us in situations where we need to extract vector elements after shuffles have already been lowered.
This patch adds support for VECTOR_EXTRACT_ELEMENT/PEXTRW/PEXTRB instructions to attempt to handle target shuffles as well. I've covered some basic scenarios including handling shuffle mask scaling and the implicit zero-extension of PEXTRW/PEXTRB, there is more that could be done here (that I've mentioned in TODOs) but I haven't found many cases where its worth it.
Taewook Oh [Mon, 27 Feb 2017 19:30:01 +0000 (19:30 +0000)]
[TailDuplicator] Maintain DebugLoc for branch instructions
Summary: Existing implementation of duplicateSimpleBB function drops DebugLoc metadata of branch instructions during the transformation. This patch addresses this issue by making newly created branch instructions to keep the metadata of replaced branch instructions.
Craig Topper [Mon, 27 Feb 2017 16:15:32 +0000 (16:15 +0000)]
[X86] Use APInt instead of SmallBitVector tracking undef elements from getTargetConstantBitsFromNode and getConstVector.
Summary:
SmallBitVector uses a malloc for more than 58 bits on a 64-bit target and more than 27 bits on a 32-bit target. Some of the vector types we deal with here use more than those number of elements and therefore cause a malloc.
APInt on the other hand supports up to 64 bits without a malloc. That's the maximum number of bits we need here so we can avoid a malloc for all cases by using APInt.
Craig Topper [Mon, 27 Feb 2017 16:15:30 +0000 (16:15 +0000)]
[X86] Use APInt instead of SmallBitVector for tracking Zeroable elements in shuffle lowering
Summary:
SmallBitVector uses a malloc for more than 58 bits on a 64-bit target and more than 27 bits on a 32-bit target. Some of the vector types we deal with here use more than those number of elements and therefore cause a malloc.
APInt on the other hand supports up to 64 bits without a malloc. That's the maximum number of bits we need here so we can avoid a malloc for all cases by using APInt.
Craig Topper [Mon, 27 Feb 2017 16:15:25 +0000 (16:15 +0000)]
[X86] Use APInt instead of SmallBitVector for tracking undef elements in constant pool shuffle decoding
Summary:
SmallBitVector uses a malloc for more than 58 bits on a 64-bit target and more than 27 bits on a 32-bit target. Some of the vector types we deal with here use more than those number of elements and therefore cause a malloc.
APInt on the other hand supports up to 64 bits without a malloc. That's the maximum number of bits we need here so we can avoid a malloc for all cases by using APInt. This will incur a minor increase in stack usage due to APInt storing the bit count separately from the data bits unlike SmallBitVector, but that should be ok.
Artur Pilipenko [Mon, 27 Feb 2017 15:44:49 +0000 (15:44 +0000)]
Loop predication expand both sides of the widened condition
This is a fix for a loop predication bug which resulted in malformed IR generation.
Loop invariant side of the widened condition is not guaranteed to be available in the preheader as is, so we need to expand it as well. See added unsigned_loop_0_to_n_hoist_length test for example.
Sjoerd Meijer [Mon, 27 Feb 2017 14:45:34 +0000 (14:45 +0000)]
AArch64InstPrinter: rewrite of printSysAlias
This is a cleanup/rewrite of the printSysAlias function. This was not using the
tablegen instruction descriptions, but was "manually" decoding the
instructions. This has been replaced with calls to lookup_XYZ_ByEncoding
tablegen calls.
This revealed several problems. First, instruction IVAU had the wrong encoding.
This was cancelled out by the parser that incorrectly matched the wrong
encoding. Second, instruction CVAP was missing from the SystemOperands tablegen
descriptions, so this has been added. And third, the required target features
were not captured in the tablegen descriptions, so support for this has also
been added.
John Brawn [Mon, 27 Feb 2017 14:40:51 +0000 (14:40 +0000)]
[ARM] LSL #0 is an alias of MOV
Currently we handle this correctly in arm, but in thumb we don't which leads to
an unpredictable instruction being emitted for LSL #0 in an IT block and SP not
being permitted in some cases when it should be.
For the thumb2 LSL we can handle this by making LSL #0 an alias of MOV in the
.td file, but for thumb1 we need to handle it in checkTargetMatchPredicate to
get the IT handling right. We also need to adjust the handling of
MOV rd, rn, LSL #0 to avoid generating the 16-bit encoding in an IT block. We
should also adjust it to allow SP in the same way that it is allowed in
MOV rd, rn, but I haven't done that here because it looks like it would take
quite a lot of work to get right.
Additionally correct the selection of the 16-bit shift instructions in
processInstruction, where it was checking if the two registers were equal when
it should have been checking if they were low. It appears that previously this
code was never executed and the 16-bit encoding was selected by default, but
the other changes I've done here have somehow made it start being used.
Current implementation would identify %v1 load as the first byte load and would mistakenly emit a i16 load from %p1.i16 address. This patch adds a check that the first byte is loaded from a non-zero offset of the first load address. This way this address can be used as the base address for the combined value. Otherwise just give up combining.
[AMDGPU] Runtime metadata fixes:
- Verify that runtime metadata is actually valid runtime metadata when assembling, otherwise we could accept the following when assembling, but ocl runtime will reject it:
.amdgpu_runtime_metadata
{ amd.MDVersion: [ 2, 1 ], amd.RandomUnknownKey, amd.IsaInfo: ...
- Make IsaInfo optional, and always emit it.
Xin Tong [Sun, 26 Feb 2017 02:11:24 +0000 (02:11 +0000)]
[SCCP] Remove manual folding of terminator instructions.
Summary:
BranchInst, SwitchInst (with non-default case) with Undef as input is not
possible at this point. As we always default-fold terminator to one target in
ResolvedUndefsIn and set the input accordingly.
So we should only have constantint/blockaddress here.
If ConstantFoldTerminator fails, that could mean 2 things.
1. ConstantFoldTerminator is doing something unexpected, i.e. not folding on constantint
or blockaddress and not making blocks that should be dead dead.
2. This is not a terminator on constantint or blockaddress. Its on a constant or
overdefined, then this block should not be dead.
Sanjoy Das [Sat, 25 Feb 2017 20:30:45 +0000 (20:30 +0000)]
[ValueTracking] Don't do an unchecked shift in ComputeNumSignBits
Summary:
Previously we used to return a bogus result, 0, for IR like `ashr %val,
-1`.
I've also added an assert checking that `ComputeNumSignBits` at least
returns 1. That assert found an already checked in test case where we
were returning a bad result for `ashr %val, -1`.
Craig Topper [Sat, 25 Feb 2017 18:43:42 +0000 (18:43 +0000)]
[AVX-512] Remove unnecessary masked versions of VCVTSS2SD and VCVTSD2SS using the scalar register class. We only have patterns for the masked intrinsics.
Craig Topper [Sat, 25 Feb 2017 18:12:25 +0000 (18:12 +0000)]
[ExecutionDepsFix] Don't make copies of LiveReg objects when collecting operands for soft instructions
Summary:
While collecting operands we make copies of the LiveReg objects which are stored in the LiveRegs array. If the instruction uses the same register multiple times we end up with multiple copies. Later we iterate through the collected list of LiveReg objects and merge DomainValues. In the process of doing this the merge function can change the contents of the original LiveReg object in the LiveRegs array, but not the copies that have been made. So when we get to the second usage of the register we end up seeing a stale copy of the LiveReg object.
To fix this I've stopped copying and now just store a pointer to the original LiveReg object. Another option might be to avoid adding the same register to the Regs array twice, but this approach seemed simpler.
The included test case exposes this bug due to an AVX-512 masked OR instruction using the same register for the passthru operand and one of the inputs to the OR operation.
NAKAMURA Takumi [Sat, 25 Feb 2017 17:04:23 +0000 (17:04 +0000)]
Revert r296215, "[PDB] General improvements to Stream library." and followings.
r296215, "[PDB] General improvements to Stream library."
r296217, "Disable BinaryStreamTest.StreamReaderObject temporarily."
r296220, "Re-enable BinaryStreamTest.StreamReaderObject."
r296244, "[PDB] Disable some tests that are breaking bots."
r296249, "Add static_cast to silence -Wc++11-narrowing."
std::errc::no_buffer_space should be used for OS-oriented errors for socket transmission.
(Seek discussions around llvm/xray.)
I could substitute s/no_buffer_space/others/g, but I revert whole them ATM.
Victor Leschuk [Sat, 25 Feb 2017 13:15:57 +0000 (13:15 +0000)]
[DebugInfo] Skip implicit_const attributes when dumping .debug_info. NFC.
When dumping .debug_info section we loop through all attributes mentioned in
.debug_abbrev section and dump values using DWARFFormValue::extractValue().
We need to skip implicit_const attributes here as their values are not
really located in .debug_info but directly in .debug_abbrev. This patch fixes
triggered assert() in DWARFFormValue::extractValue() caused by trying to
access implicit_const values from .debug_info.
Nirav Dave [Sat, 25 Feb 2017 11:43:58 +0000 (11:43 +0000)]
In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Recommiting after fixup of 32-bit aliasing sign offset bug in DAGCombiner.
* Simplify Consecutive Merge Store Candidate Search
Now that address aliasing is much less conservative, push through
simplified store merging search and chain alias analysis which only
checks for parallel stores through the chain subgraph. This is cleaner
as the separation of non-interfering loads/stores from the
store-merging logic.
When merging stores search up the chain through a single load, and
finds all possible stores by looking down from through a load and a
TokenFactor to all stores visited.
This improves the quality of the output SelectionDAG and the output
Codegen (save perhaps for some ARM cases where we correctly constructs
wider loads, but then promotes them to float operations which appear
but requires more expensive constant generation).
Some minor peephole optimizations to deal with improved SubDAG shapes (listed below)
Additional Minor Changes:
1. Finishes removing unused AliasLoad code
2. Unifies the chain aggregation in the merged stores across code
paths
3. Re-add the Store node to the worklist after calling
SimplifyDemandedBits.
4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is
arbitrary, but seems sufficient to not cause regressions in
tests.
5. Remove Chain dependencies of Memory operations on CopyfromReg
nodes as these are captured by data dependence
6. Forward loads-store values through tokenfactors containing
{CopyToReg,CopyFromReg} Values.
7. Peephole to convert buildvector of extract_vector_elt to
extract_subvector if possible (see
CodeGen/AArch64/store-merge.ll)
8. Store merging for the ARM target is restricted to 32-bit as
some in some contexts invalid 64-bit operations are being
generated. This can be removed once appropriate checks are
added.
This finishes the change Matt Arsenault started in r246307 and
jyknight's original patch.
Many tests required some changes as memory operations are now
reorderable, improving load-store forwarding. One test in
particular is worth noting:
CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store
forwarding converts a load-store pair into a parallel store and
a memory-realized bitcast of the same value. However, because we
lose the sharing of the explicit and implicit store values we
must create another local store. A similar transformation
happens before SelectionDAG as well.
Zachary Turner [Sat, 25 Feb 2017 00:44:30 +0000 (00:44 +0000)]
[PDB] General improvements to Stream library.
This adds various new functionality and cleanup surrounding the
use of the Stream library. Major changes include:
* Renaming of all classes for more consistency / meaningfulness
* Addition of some new methods for reading multiple values at once.
* Full suite of unit tests for reader / writer functionality.
* Full set of doxygen comments for all classes.
* Streams now store their own endianness.
* Fixed some bugs in a few of the classes that were discovered
by the unit tests.
Zachary Turner [Sat, 25 Feb 2017 00:33:34 +0000 (00:33 +0000)]
[PDB] Rename Stream related source files.
This is part of a larger effort to get the Stream code moved
up to Support. I don't want to do it in one large patch, in
part because the changes are so big that it will treat everything
as file deletions and add, losing history in the process.
Aside from that though, it's just a good idea in general to
make small changes.
So this change only changes the names of the Stream related
source files, and applies necessary source fix ups.
Summary:
In Preparation for graph comparison, this patch breaks out the color
choice code from xray-graph into a library and adds polynomials for
the Sequential and Difference sets from ColorBrewer.
Rong Xu [Sat, 25 Feb 2017 00:00:36 +0000 (00:00 +0000)]
[PGO] Directory name stripping in global identifier for static functions
Current internal option -static-func-full-module-prefix keeps all the
directory path the profile counter names for static functions. The default
of this option is false. This strips the directory names from the source
filename which is problematic:
(1) it creates linker errors for profile-generation compilation, exposed in
our internal benchmarks. We are seeing messages like
"warning: relocation refers to discarded section".
This is due to the name conflicts after the stripping.
(2) the stripping only applies to getPGOFuncName.
Current Thin-LTO module importing for the indirect-calls assumes
the source directory name not being stripped. Current default value
for this option can potentially prevent some inter-module
indirect-call-promotions.
This patch turns the default value for -static-func-full-module-prefix to true.
The second part of the patch is to have an alternative implementation under
the internal option -static-func-strip-dirname-prefix=<value>
This options specifies level of directories to be stripped from the source
filename. Using a large value as the parameter has the same effect as
-static-func-full-module-prefix.
projects / llvm / log