Jake Ehrlich [Wed, 1 Nov 2017 23:14:48 +0000 (23:14 +0000)]
[yaml2obj][ELF] Add support for setting alignment in program headers
Sometimes program headers have larger alignments than any of the
sections they contain. Currently yaml2obj can't produce such files. A
bug recently appeared in llvm-objcopy that failed in such a case. I'd
like to be able to add tests to llvm-objcopy for such cases.
This change adds an optional alignment parameter to program headers that
will be used instead of calculating the alignment.
whitequark [Wed, 1 Nov 2017 22:18:52 +0000 (22:18 +0000)]
[LLVM-C] Expose functions to create debug locations via DIBuilder.
These include:
* Several functions for creating an LLVMDIBuilder,
* LLVMDIBuilderCreateCompileUnit,
* LLVMDIBuilderCreateFile,
* LLVMDIBuilderCreateDebugLocation.
Simon Pilgrim [Wed, 1 Nov 2017 21:52:29 +0000 (21:52 +0000)]
[X86][SSE] Add PACKUS support to LowerTruncate
Similar to the existing code to lower to PACKSS, we can use PACKUS if the input vector's leading zero bits extend all the way to the packed/truncated value.
We have to account for pre-SSE41 targets not supporting PACKUSDW
Rui Ueyama [Wed, 1 Nov 2017 21:38:14 +0000 (21:38 +0000)]
Rewrite FileOutputBuffer as two separate classes.
This patch is to rewrite FileOutputBuffer as two separate classes;
one for file-backed output buffer and the other for memory-backed
output buffer. I think the new code is easier to follow because two
different implementations are now actually separated as different
classes.
Unlike the previous implementation, the class that does not replace the
final output file using rename(2) does not create a temporary file at
all. Instead, it allocates memory using mmap(2) and use it. I think
this is an improvement because it is now guaranteed that the temporary
memory region doesn't trigger any I/O and there's now zero chance to
leave a temporary file behind. Also, it shouldn't impose new restrictions
because were using mmap IO too.
Craig Topper [Wed, 1 Nov 2017 21:00:59 +0000 (21:00 +0000)]
[X86] Add custom code to EVEX to VEX pass to turn unmasked 128-bit VPALIGND/Q into VPALIGNR if the extended registers aren't being used.
This will enable us to prefer VALIGND/Q during shuffle lowering in order to get the extended register encoding space when BWI isn't available. But if we end up not using the extended registers we can switch VPALIGNR for the shorter VEX encoding.
Dehao Chen [Wed, 1 Nov 2017 20:26:47 +0000 (20:26 +0000)]
Include GUIDs from the same module when computing GUIDs that needs to be imported.
Summary: In the compile phase of SamplePGO+ThinLTO, ICP is not invoked. Instead, indirect call targets will be included as function metadata for ThinIndex to buidl the call graph. This should not only include functions defined in other modules, but also functions defined in the same module, otherwise ThinIndex may find the callee dead and eliminate it, while ICP in backend will revive the symbol, which leads to undefined symbol.
Daniel Sanders [Wed, 1 Nov 2017 19:57:57 +0000 (19:57 +0000)]
[globalisel][tablegen] Add support for multi-insn emission
The importer will now accept nested instructions in the result pattern such as
(ADDWrr $a, (SUBWrr $b, $c)). This is only valid when the nested instruction
def's a single vreg and the parent instruction consumes a single vreg where a
nested instruction is specified. The importer will automatically create a vreg
to connect the two using the type information from the pattern. This vreg will
be constrained to the register classes given in the instruction definitions*.
* REG_SEQUENCE is explicitly rejected because of this. The definition doesn't
constrain to a register class and it therefore needs special handling.
Craig Topper [Wed, 1 Nov 2017 18:10:06 +0000 (18:10 +0000)]
[X86] Prevent fast isel from folding loads into the instructions listed in hasPartialRegUpdate.
This patch moves the check for opt size and hasPartialRegUpdate into the lower level implementation of foldMemoryOperandImpl to catch the entry point that fast isel uses.
We're still folding undef register instructions in AVX that we should also probably disable, but that's a problem for another patch.
Unfortunately, this requires reordering a bunch of functions which is why the diff is so large. I can do the function reordering separately if we want.
LTO: Apply global DCE to ThinLTO modules at LTO opt level 0.
This is necessary because DCE is applied to full LTO modules. Without
this change, a reference from a dead ThinLTO global to a dead full
LTO global will result in an undefined reference at link time.
This problem is only observable when --gc-sections is disabled, or
when targeting COFF, as the COFF port of lld requires all symbols to
have a definition even if all references are dead (this is consistent
with link.exe).
This change also adds an EliminateAvailableExternally pass at -O0. This
is necessary to handle the situation on Windows where a non-prevailing
copy of a linkonce_odr function has an SEH filter function; any
such filters must be DCE'd because they will contain a call to the
llvm.localrecover intrinsic, passing as an argument the address of the
function that the filter belongs to, and llvm.localrecover requires
this function to be defined locally.
Petar Jovanovic [Wed, 1 Nov 2017 16:04:11 +0000 (16:04 +0000)]
Correct dwarf unwind information in function epilogue for X86
This patch aims to provide correct dwarf unwind information in function
epilogue for X86.
It consists of two parts. The first part inserts CFI instructions that set
appropriate cfa offset and cfa register in emitEpilogue() in
X86FrameLowering. This part is X86 specific.
The second part is platform independent and ensures that:
- CFI instructions do not affect code generation
- Unwind information remains correct when a function is modified by
different passes. This is done in a late pass by analyzing information
about cfa offset and cfa register in BBs and inserting additional CFI
directives where necessary.
Changed CFI instructions so that they:
- are duplicable
- are not counted as instructions when tail duplicating or tail merging
- can be compared as equal
Added CFIInstrInserter pass:
- analyzes each basic block to determine cfa offset and register valid at
its entry and exit
- verifies that outgoing cfa offset and register of predecessor blocks match
incoming values of their successors
- inserts additional CFI directives at basic block beginning to correct the
rule for calculating CFA
Having CFI instructions in function epilogue can cause incorrect CFA
calculation rule for some basic blocks. This can happen if, due to basic
block reordering, or the existence of multiple epilogue blocks, some of the
blocks have wrong cfa offset and register values set by the epilogue block
above them.
CFIInstrInserter is currently run only on X86, but can be used by any target
that implements support for adding CFI instructions in epilogue.
Geoff Berry [Wed, 1 Nov 2017 15:16:50 +0000 (15:16 +0000)]
[BranchProbabilityInfo] Handle irreducible loops.
Summary:
Compute the strongly connected components of the CFG and fall back to
use these for blocks that are in loops that are not detected by
LoopInfo when computing loop back-edge and exit branch probabilities.
Max Kazantsev [Wed, 1 Nov 2017 13:21:56 +0000 (13:21 +0000)]
Revert rL311205 "[IRCE] Fix buggy behavior in Clamp"
This patch reverts rL311205 that was initially a wrong fix. The real problem
was in intersection of signed and unsigned ranges (see rL316552), and the
patch being reverted masked the problem instead of fixing it.
By now, the test against which rL311205 was made works OK even without this
code. This revert patch also contains a test case that demonstrates incorrect
behavior caused by rL311205: it is caused by incorrect choise of signed max
instead of unsigned.
Simon Pilgrim [Wed, 1 Nov 2017 11:47:44 +0000 (11:47 +0000)]
[X86][SSE] Truncate with PACKSS any input with sufficient sign-bits
So far we've only been using PACKSS truncations with 'all-bits or zero-bits' patterns (vector comparison results etc.). When really we can safely use it for any case as long as the number of sign bits reach down to the last 16-bits (or 8-bits if we're truncating to bytes).
The next steps after this is add the equivalent support for PACKUS and to support packing to sub-128 bit vectors for truncating stores etc.
Florian Hahn [Wed, 1 Nov 2017 09:48:12 +0000 (09:48 +0000)]
[CodeExtractor] Fix iterator invalidation in findOrCreateBlockForHoisting.
Summary:
By replacing branches to CommonExitBlock, we remove the node from
CommonExitBlock's predecessors, invalidating the iterator. The problem
is exposed when the common exit block has multiple predecessors and
needs to sink lifetime info. The modification in the test case trigger
the issue.
Jake Ehrlich [Wed, 1 Nov 2017 00:18:51 +0000 (00:18 +0000)]
Add system-linux to allow tests run with llvm-lit to restrict themselves to linux
I need a test that only runs in a reasonable amount of time on systems
that have sparse files. The broadest class of systems that support
sparse files are linux systems. So restricting my test to linux systems
should suffice. This change adds the system-linux feature to llvm-lit so
that it can be required.
Mitch Phillips [Tue, 31 Oct 2017 23:20:05 +0000 (23:20 +0000)]
Parse DWARF information to reduce false positives.
Summary: Help differentiate code and data by parsing DWARF information. This will reduce false positive rates where data is placed in executable sections and is mistakenly parsed as code, resulting in an inflation in the number of indirect CF instructions (and hence an inflation of the number of unprotected).
Also prints the DWARF line data around the region of each indirect CF instruction.
Daniel Sanders [Tue, 31 Oct 2017 23:03:18 +0000 (23:03 +0000)]
Re-commit: [globalisel][tablegen] Keep track of the insertion point while adding BuildMIAction's. NFC
Multi-instruction emission needs to ensure the the instructions are generated
a depth-first fashion. For example:
(ADDWrr (SUBWrr a, b), c)
needs to emit the SUBWrr before the ADDWrr. However, our walk over
TreePatternNode's is highly context sensitive which makes it difficult to append
BuildMIActions in the order we want. To fix this, we now keep track of the
insertion point as we add actions. This will allow multi-insn emission to insert
BuildMI's in the correct place.
The previous commit failed on the Ubuntu bots using GCC 4.8. These bots lack the
const_iterator forms of insert() and emplace() that were added in C++11. As a
result I've switched the const_iterators to iterators.
Philip Reames [Tue, 31 Oct 2017 22:56:16 +0000 (22:56 +0000)]
[SimplifyIndVar] Inline makIVComparisonInvariant to eleminate code duplication [NFC]
This formulation might be slightly slower since I eagerly compute the cheap replacements. If anyone sees this having a compile time impact, let me know and I'll use lazy population instead.
Daniel Sanders [Tue, 31 Oct 2017 21:54:52 +0000 (21:54 +0000)]
Revert r317040: [globalisel][tablegen] Keep track of the insertion point while adding BuildMIAction's. NFC
The same bots fail but I believe I know what the issue is now. These bots are
missing the const_iterator versions of insert/emplace/etc. that were introduced
in C++11.
Reid Kleckner [Tue, 31 Oct 2017 21:52:15 +0000 (21:52 +0000)]
[codeview] Merge file checksum entries for DIFiles with the same absolute path
Change the map key from DIFile* to the absolute path string. Computing
the absolute path isn't expensive because we already have a map that
caches the full path keyed on DIFile*.
Daniel Sanders [Tue, 31 Oct 2017 21:34:53 +0000 (21:34 +0000)]
Re-commit: [globalisel][tablegen] Keep track of the insertion point while adding BuildMIAction's. NFC
Multi-instruction emission needs to ensure the the instructions are generated
a depth-first fashion. For example:
(ADDWrr (SUBWrr a, b), c)
needs to emit the SUBWrr before the ADDWrr. However, our walk over
TreePatternNode's is highly context sensitive which makes it difficult to append
BuildMIActions in the order we want. To fix this, we now keep track of the
insertion point as we add actions. This will allow multi-insn emission to insert
BuildMI's in the correct place.
The previous commit failed on the Ubuntu bots using GCC 4.8. These bots didn't
like a call to emplace(). I've replaced it with insert() to see if it's a quirk
of the C++11 support.
Daniel Sanders [Tue, 31 Oct 2017 19:54:05 +0000 (19:54 +0000)]
[globalisel][tablegen] Keep track of the insertion point while adding BuildMIAction's. NFC
Multi-instruction emission needs to ensure the the instructions are generated
a depth-first fashion. For example:
(ADDWrr (SUBWrr a, b), c)
needs to emit the SUBWrr before the ADDWrr. However, our walk over
TreePatternNode's is highly context sensitive which makes it difficult to append
BuildMIActions in the order we want. To fix this, we now keep track of the
insertion point as we add actions. This will allow multi-insn emission to insert
BuildMI's in the correct place.
Daniel Sanders [Tue, 31 Oct 2017 19:09:29 +0000 (19:09 +0000)]
[globalisel][tablegen] Factor out implicit def/use renderers from createAndImportInstructionRenderer(). NFC
Multi-instruction emission will require that we have separate handling for
the defs between the implicitly created temporaries and the rule outputs.
The former require new temporary vregs while the latter should copy existing
operands. Factor out the implicit def/use renderers to minimize the code
duplication when we implement that.
Craig Topper [Tue, 31 Oct 2017 19:03:51 +0000 (19:03 +0000)]
[SimplifyCFG] Use a more generic name for the selects created by SpeculativelyExecuteBB to prevent long names from being created
Currently the selects are created with the names of their inputs concatenated together. It's possible to get cases that chain these selects together resulting in long names due to multiple levels of concatenation. Our internal branch of llvm managed to generate names over 100000 characters in length on a particular test due to an extreme compounding of the names.
This patch changes the name to a generic name that is not dependent on its inputs.
Craig Topper [Tue, 31 Oct 2017 19:03:49 +0000 (19:03 +0000)]
[SimplifyCFG] Regenerate some test cases using update_test_checks.py to prepare for an upcoming commit. NFC
A future commit will change how some of the value names in the IR are generated which causes these tests to break in their current form. The script generates checks with regular expressions so it should be immune.
Daniel Sanders [Tue, 31 Oct 2017 18:50:24 +0000 (18:50 +0000)]
[globalisel][tablegen] Add infrastructure to potentially allow BuildMIAction to choose a mutatable instruction. NFC
Prepare for multiple instruction emission by allowing BuildMIAction to
search for a suitable matcher that will support mutation.
This patch deliberately neglects to add matchers aside from the root to
preserve NFC. That said, it should be noted that until we support mutations
other than just the opcode the chances of finding a non-root instruction
for which canMutate() is true, is essentially zero. Furthermore in the
presence of multi-instruction emission the chances of finding any
instruction for which canMutate() is true is also zero. Nevertheless, we
can't continue to require that all BuildMIAction's consider the root of the match
to be recyclable due to the risk of recycling it twice in the same rule.
Rui Ueyama [Tue, 31 Oct 2017 17:37:20 +0000 (17:37 +0000)]
[Support] Make the default chunk size of raw_fd_ostream to 1 GiB.
Previously, we call write(2) for each 32767 byte chunk. That is not
efficient because Linux can handle much larger write requests.
This patch changes the chunk size on Linux to 1 GiB.
This patch also changes the default chunks size to SSIZE_MAX. I think
that doesn't in practice change this function's behavior on any operating
system because SSIZE_MAX on 64-bit machine is unrealistically large,
and writing 2 GiB (SSIZE_MAX on 32-bit) on a 32-bit machine by a single
call of write(2) is also unrealistic, as the userspace is usually
limited to 2 GiB. That said, it is in general a good thing to do because
a write larger than SSIZE_MAX is implementation-defined in POSIX.
Nico Weber [Tue, 31 Oct 2017 16:39:47 +0000 (16:39 +0000)]
LTOModule::isBitcodeFile() shouldn't assert when returning false.
Fixes a bunch of assert-on-invalid-bitcode regressions after 315483.
Expected<> calls assertIsChecked() in its dtor, and operator bool() only calls
setChecked() if there's no error. So for functions that don't return an error
itself, the Expected<> version needs explicit code to disarm the error that the
ErrorOr<> code didn't need.
Florian Hahn [Tue, 31 Oct 2017 14:06:31 +0000 (14:06 +0000)]
[Reassociate] Remove FIXME from looptest.ll (NFC)
Summary: The loop invariant add (i+j) is reassoicated, I think the FIXME can be removed, because this is what the test case tries to check (AFAIK). I also changed the test to use FileCheck.
This patch adds the --threads option to dsymutil to process
architectures in parallel. The feature is already present in the version
distributed with Xcode, but was not yet upstreamed.
This is NFC as far as the linking behavior is concerned. As threads are
used automatically, the current tests cover the change in
implementation.
Teresa Johnson [Tue, 31 Oct 2017 12:56:09 +0000 (12:56 +0000)]
[ThinLTO] Double bits of module hash used for renaming
Summary:
Use 64 instead of 32 bits of the module hash as the suffix when renaming
after promotion to reduce the likelihood of a collision (which we
observed in a binary when using 32 bits).
Matthew Simpson [Tue, 31 Oct 2017 12:34:02 +0000 (12:34 +0000)]
[InstCombine] Simplify selects that test cmpxchg instructions
If a select instruction tests the returned flag of a cmpxchg instruction and
selects between the returned value of the cmpxchg instruction and its compare
operand, the result of the select will always be equal to its false value.
Ayman Musa [Tue, 31 Oct 2017 11:39:31 +0000 (11:39 +0000)]
Adding a shufflevector and select LLVM IR instructions fuzz tool
Based on similar python tool - utils/shuffle-fuzz.py - this tool extends the ability of it's previous by optionally attaching select instruction to the generated shufflevector instructions.
This was mainly developed to perform exhaustive testing of the X86 AVX512 masked shuffle instructions. But yet it can be used for various other targets.
The general design of the implementation is much modular than the original shuffle_fuzz.py tool, which makes it easier for anyone to extend it further.
David Green [Tue, 31 Oct 2017 10:47:46 +0000 (10:47 +0000)]
[LoopUnroll] Clean up remarks for unroll remainder
The optimisation remarks for loop unrolling with an unrolled remainder looks something like:
test.c:7:18: remark: completely unrolled loop with 3 iterations [-Rpass=loop-unroll]
C[i] += A[i*N+j];
^
test.c:6:9: remark: unrolled loop by a factor of 4 with run-time trip count [-Rpass=loop-unroll]
for(int j = 0; j < N; j++)
^
This removes the first of the two messages.
[AVX512] Adding new patterns for extract_subvector of vXi1
extract subvector of vXi1 from vYi1 is poorly supported by LLVM and most of the time end with an assertion.
This patch fixes this issue by adding new patterns to the TD file.
Max Kazantsev [Tue, 31 Oct 2017 06:19:05 +0000 (06:19 +0000)]
[IRCE][NFC] Rename fields of InductiveRangeCheck
Rename `Offset`, `Scale`, `Length` into `Begin`, `Step`, `End` respectively
to make naming of similar entities for Ranges and Range Checks more
consistent.
Craig Topper [Tue, 31 Oct 2017 06:01:04 +0000 (06:01 +0000)]
[X86] Make AVX512_512_SET0 XMM16-31 lower to 128-bit XOR when AVX512VL is enabled. Use 128-bit VLX instruction when VLX is enabled.
Unfortunately, this weakens our ability to do domain fixing when AVX512DQ is not enabled, but it is consistent with our 256-bit behavior.
Maybe we should add custom handling to domain fixing to allow EVEX integer XOR/AND/OR/ANDN to switch to VEX encoded fp instructions if the high registers aren't being used?
Philip Reames [Tue, 31 Oct 2017 05:16:46 +0000 (05:16 +0000)]
[IndVarSimplify] Simplify code using preheader assumption
As noted in the nice block comment, the previous code didn't actually handle multi-entry loops correctly, it just assumed SCEV didn't analyze such loops. Given SCEV has comments to the contrary, that seems a bit suspect. More importantly, the pass actually requires loopsimplify form which ensures a loop-preheader is available. Remove the excessive generaility and shorten the code greatly.
Note that we do successfully analyze many multi-entry loops, but we do so by converting them to single entry loops. See the added test case.
Max Kazantsev [Tue, 31 Oct 2017 05:07:56 +0000 (05:07 +0000)]
Reapply "[GVN] Prevent LoadPRE from hoisting across instructions that don't pass control flow to successors"
This patch fixes the miscompile that happens when PRE hoists loads across guards and
other instructions that don't always pass control flow to their successors. PRE is now prohibited
to hoist across such instructions because there is no guarantee that the load standing after such
instruction is still valid before such instruction. For example, a load from under a guard may be
invalid before the guard in the following case:
int array[LEN];
...
guard(0 <= index && index < LEN);
use(array[index]);
Philip Reames [Tue, 31 Oct 2017 04:19:06 +0000 (04:19 +0000)]
[SimplifyIndVar] Extract out invariant expression handling
Previously, the code returned early from the *function* when it couldn't find a free expansion, it should be returning from the *transform*. I don't have a test case, noticed this via inspection.
As a follow up, I'm going to revisit the logic in the extract function. I think that essentially the whole helper routine can be replaced with SCEVExpander, but I wanted to do that in a series of separate commits.
Shoaib Meenai [Tue, 31 Oct 2017 01:30:46 +0000 (01:30 +0000)]
[cmake] Make check_linker_flags operate via linker flags
`check_linker_flags` currently sets the *compiler* flags (via
`CMAKE_REQUIRED_FLAGS`), and thus implicitly relies on cmake's default
behavior of passing the compiler flags to the linker. This breaks when
cmake's build rules have been altered to not pollute the link line with
compiler flags (which can be desirable for build cleanliness). Instead,
set `CMAKE_EXE_LINKER_FLAGS` explicitly and use `CMP0056` to ensure the
linker flags are passed along. Additionally, since we're inside a
function, we can just alter the variable directly (as the alteration
will be limited to the scope of the function) rather than saving and
restoring the old value.