Quentin Colombet [Tue, 15 Dec 2015 03:28:11 +0000 (03:28 +0000)]
[ShrinkWrapping] Do not choose restore point inside loops.
The post-dominance property is not sufficient to guarantee that a restore point
inside a loop is safe.
E.g.,
while(1) {
Save
Restore
if (...)
break;
use/def CSRs
}
All the uses/defs of CSRs are dominated by Save and post-dominated
by Restore. However, the CSRs uses are still reachable after
Restore and before Save are executed.
JF Bastien [Tue, 15 Dec 2015 02:02:51 +0000 (02:02 +0000)]
WebAssembly: test global array indexing
This case was tested in the linker from code, but not from globals indexing into other globals. The linker currently barfs on this, ncbray volunteered to fix it.
Mehdi Amini [Tue, 15 Dec 2015 01:44:07 +0000 (01:44 +0000)]
Instcombine: destructor loads of structs that do not contains padding
For non padded structs, we can just proceed and deaggregate them.
We don't want ot do this when there is padding in the struct as to not
lose information about this padding (the subsequents passes would then
try hard to preserve the padding, which is undesirable).
Also update extractvalue.ll and cast.ll so that they use structs with padding.
Remove the FIXME in the extractvalue of laod case as the non padded case is
handled when processing the load, and we don't want to do it on the padded
case.
Mehdi Amini [Tue, 15 Dec 2015 00:59:19 +0000 (00:59 +0000)]
Add a C++11 ThreadPool implementation in LLVM
This is a very simple implementation of a thread pool using C++11
thread. It accepts any std::function<void()> for asynchronous
execution. Individual task can be synchronize using the returned
future, or the client can block on the full queue completion.
In case LLVM is configured with Threading disabled, it falls back
to sequential execution using std::async with launch:deferred.
This is intended to support parallelism for ThinLTO processing in
linker plugin, but is generic enough for any other uses.
This is a recommit of r255444 ; trying to workaround a bug in the
MSVC 2013 standard library. I think I was hit by:
Mehdi Amini [Tue, 15 Dec 2015 00:38:05 +0000 (00:38 +0000)]
Add a C++11 ThreadPool implementation in LLVM
This is a very simple implementation of a thread pool using C++11
thread. It accepts any std::function<void()> for asynchronous
execution. Individual task can be synchronize using the returned
future, or the client can block on the full queue completion.
In case LLVM is configured with Threading disabled, it falls back
to sequential execution using std::async with launch:deferred.
This is intended to support parallelism for ThinLTO processing in
linker plugin, but is generic enough for any other uses.
This is a recommit of r255444 ; trying to workaround a bug in the
MSVC 2013 standard library. I think I was hit by:
Profile symbols have long prefixes which waste space and creating pressure for linker.
This patch shortens the prefixes to minimal length without losing verbosity.
Justin Bogner [Mon, 14 Dec 2015 23:22:48 +0000 (23:22 +0000)]
LoopRotate: Convert the methods of LoopRotate to utility functions. NFC
This moves the actual work to do loop rotation into standalone
functions with the analysis results they need passed in as arguments,
leaving the class itself as a relatively simple shim. This will make
the functions easy to reuse when we're ready to port this
transformation to the new pass manager.
Justin Bogner [Mon, 14 Dec 2015 23:22:44 +0000 (23:22 +0000)]
LoopRotate: Reorder some method implementations. NFC
This just moves some callers after their callees. My next patch will
convert some of these methods to stand alone functions, and that diff
is more obviously NFC if I move these first. That change, in turn,
will make it much easier to port this pass to the new pass manager
once the loop pass manager is in place.
Rafael Espindola [Mon, 14 Dec 2015 23:17:03 +0000 (23:17 +0000)]
Use diagnostic handler in the LLVMContext
This patch converts code that has access to a LLVMContext to not take a
diagnostic handler.
This has a few advantages
* It is easier to use a consistent diagnostic handler in a single program.
* Less clutter since we are not passing a handler around.
It does make it a bit awkward to implement some C APIs that return a
diagnostic string. I will propose new versions of these APIs and
deprecate the current ones.
Chih-Hung Hsieh [Mon, 14 Dec 2015 22:08:36 +0000 (22:08 +0000)]
[X86] Part 2 to fix x86-64 fp128 calling convention.
Part 1 was submitted in http://reviews.llvm.org/D15134.
Changes in this part:
* X86RegisterInfo.td, X86RecognizableInstr.cpp: Add FR128 register class.
* X86CallingConv.td: Pass f128 values in XMM registers or on stack.
* X86InstrCompiler.td, X86InstrInfo.td, X86InstrSSE.td:
Add instruction selection patterns for f128.
* X86ISelLowering.cpp:
When target has MMX registers, configure MVT::f128 in FR128RegClass,
with TypeSoftenFloat action, and custom actions for some opcodes.
Add missed cases of MVT::f128 in places that handle f32, f64, or vector types.
Add TODO comment to support f128 type in inline assembly code.
* SelectionDAGBuilder.cpp:
Fix infinite loop when f128 type can have
VT == TLI.getTypeToTransformTo(Ctx, VT).
* Add unit tests for x86-64 fp128 type.
Sanjay Patel [Mon, 14 Dec 2015 21:59:03 +0000 (21:59 +0000)]
add fast-math-flags to 'call' instructions (PR21290)
This patch adds optional fast-math-flags (the same that apply to fmul/fadd/fsub/fdiv/frem/fcmp)
to call instructions in IR. Follow-up patches would use these flags in LibCallSimplifier, add
support to clang, and extend FMF to the DAG for calls.
We'd like to be able to optimize sqrt(x*x) into fabs(x). We do this today using a function-wide
attribute for unsafe-math, but we really want to trigger on the instructions themselves:
%z = tail call fast float @sqrtf(float %y)
because in an LTO build it's possible that calls with fast semantics have been inlined into a
function with non-fast semantics.
The code changes and tests are based on the recent commits that added "notail":
http://reviews.llvm.org/rL252368
and added FMF to fcmp:
http://reviews.llvm.org/rL241901
[Packetizer] Add AliasAnalysis as a parameter to the packetizer
This will make the depedence graph more accurate if an alias analysis
is provided. If nullptr is specified in its place, the behavior will
remain as it is currently.
Pete Cooper [Mon, 14 Dec 2015 20:29:16 +0000 (20:29 +0000)]
Add missing vtable anchor's.
The following description is from http://reviews.llvm.org/D15481:
ICmpInst, GetElementPtrInst and PHINode have no anchor functions. This causes the vtable and the type info (if RTTI is enabled in user code) to be emitted in multiple translation units.
Before 3.7, the destructors were the key functions for these nodes, but they have been removed.
There have been discussions about this here: http://lists.llvm.org/pipermail/llvm-dev/2015-August/089010.html and here: http://lists.llvm.org/pipermail/llvm-dev/2015-December/092921.html.
Cong Hou [Mon, 14 Dec 2015 19:11:54 +0000 (19:11 +0000)]
Remove the successor probabilities normalization in tail duplication pass.
The normalization may cause assertion failures on SystemZ and some out-of-tree
tests. The root cause is that unknown probabilities are materialized into known
ones by calling getSuccProbability(), which is then used to add another
successor to the same MBB which results in mixed known and unknown
probabilities. But currently those mixed probabilities cannot be normalized.
I will compose another patch to fix the root issue.
David Majnemer [Mon, 14 Dec 2015 18:34:23 +0000 (18:34 +0000)]
[IR] Remove terminatepad
It turns out that terminatepad gives little benefit over a cleanuppad
which calls the termination function. This is not sufficient to
implement fully generic filters but MSVC doesn't support them which
makes terminatepad a little over-designed.
Paul Robinson [Mon, 14 Dec 2015 18:33:18 +0000 (18:33 +0000)]
FastISel needs to remove dead code when it bails out.
When FastISel fails to translate an instruction it hands off code
generation to SelectionDAG. Before it does so, it may have generated
local value instructions to feed phi nodes in successor blocks. These
instructions will then be generated again by SelectionDAG, causing
duplication and less efficient code, including extra spill
instructions.
This is a fix for PR25543:
https://llvm.org/bugs/show_bug.cgi?id=25543
The idea is to take the existing fold of:
bitcast ( trunc ( lshr ( bitcast X))) --> extractelement (bitcast X)
( http://reviews.llvm.org/rL112232 )
And break it into less specific transforms so we'll catch more cases such as
the example in the bug report:
bitcast ( trunc ( lshr ( bitcast X))) -->
bitcast ( extractelement (bitcast X)) -->
extractelement (bitcast X)
Enabling patches for this change:
http://reviews.llvm.org/rL255399 (combine bitcasts)
http://reviews.llvm.org/rL255433 (canonicalize extractelement(bitcast X))
This patch add support for variadic argument for AArch64. All the MSAN
unit tests are not passing as well the signal_stress_test (currently
set as XFAIl for aarch64).
James Molloy [Mon, 14 Dec 2015 10:57:01 +0000 (10:57 +0000)]
Don't create unnecessary PHIs
In conditional store merging, we were creating PHIs when we didn't
need to. If the value to be predicated isn't defined in the block
we're predicating, then it doesn't need a PHI at all (because we only
deal with triangles and diamonds, any value not in the predicated BB
must dominate the predicated BB).
This fixes a large code size increase in some benchmarks in a popular embedded benchmark suite.
David Blaikie [Mon, 14 Dec 2015 07:42:00 +0000 (07:42 +0000)]
[llvm-dwp] Deduplicate type units
It's O(N^2) because it does a simple walk through the existing types to
find duplicates, but that will be fixed in a follow-up commit to use a
mapping data structure of some kind.
Cong Hou [Sun, 13 Dec 2015 16:55:46 +0000 (16:55 +0000)]
[LoopVectorizer] Refine loop vectorizer's register usage calculator by ignoring specific instructions.
(This is the second attempt to check in this patch: REQUIRES: asserts is added
to reg-usage.ll now.)
LoopVectorizationCostModel::calculateRegisterUsage() is used to estimate the
register usage for specific VFs. However, it takes into account many
instructions that won't be vectorized, such as induction variables,
GetElementPtr instruction, etc.. This makes the loop vectorizer too conservative
when choosing VF. In this patch, the induction variables that won't be
vectorized plus GetElementPtr instruction will be added to ValuesToIgnore set
so that their register usage won't be considered any more.
Cong Hou [Sun, 13 Dec 2015 09:26:17 +0000 (09:26 +0000)]
Normalize MBB's successors' probabilities in several locations.
This patch adds some missing calls to MBB::normalizeSuccProbs() in several
locations where it should be called. Those places are found by checking if the
sum of successors' probabilities is approximate one in MachineBlockPlacement
pass with some instrumented code (not in this patch).
Cong Hou [Sun, 13 Dec 2015 08:44:08 +0000 (08:44 +0000)]
[LoopVectorizer] Refine loop vectorizer's register usage calculator by ignoring specific instructions.
LoopVectorizationCostModel::calculateRegisterUsage() is used to estimate the
register usage for specific VFs. However, it takes into account many
instructions that won't be vectorized, such as induction variables,
GetElementPtr instruction, etc.. This makes the loop vectorizer too conservative
when choosing VF. In this patch, the induction variables that won't be
vectorized plus GetElementPtr instruction will be added to ValuesToIgnore set
so that their register usage won't be considered any more.
Nico Weber [Sun, 13 Dec 2015 04:14:39 +0000 (04:14 +0000)]
Revert r255444.
It doesn't build on Windows and broke the Windows LLD and LLDB bots:
http://lab.llvm.org:8011/builders/lld-x86_64-win7/builds/27693/steps/build_Lld/logs/stdio
http://lab.llvm.org:8011/builders/lldb-x86-windows-msvc/builds/13468/steps/build/logs/stdio
Mehdi Amini [Sat, 12 Dec 2015 22:55:25 +0000 (22:55 +0000)]
Add a C++11 ThreadPool implementation in LLVM
This is a very simple implementation of a thread pool using C++11
thread. It accepts any std::function<void()> for asynchronous
execution. Individual task can be synchronize using the returned
future, or the client can block on the full queue completion.
In case LLVM is configured with Threading disabled, it falls back
to sequential execution using std::async with launch:deferred.
This is intended to support parallelism for ThinLTO processing in
linker plugin, but is generic enough for any other uses.
Manuel Jacob [Sat, 12 Dec 2015 21:33:31 +0000 (21:33 +0000)]
Partially fix memcpy / memset / memmove lowering in SelectionDAG construction if address space != 0.
Summary:
Previously SelectionDAGBuilder asserted that the pointer operands of
memcpy / memset / memmove intrinsics are in address space < 256. This assert
implicitly assumed the X86 backend, where all address spaces < 256 are
equivalent to address space 0 from the code generator's point of view. On some
targets (R600 and NVPTX) several address spaces < 256 have a target-defined
meaning, so this assert made little sense for these targets.
This patch removes this wrong assertion and adds extra checks before lowering
these intrinsics to library calls. If a pointer operand can't be casted to
address space 0 without changing semantics, a fatal error is reported to the
user.
The new behavior should be valid for all targets that give address spaces != 0
a target-specified meaning (NVPTX, R600, X86). NVPTX lowers big or
variable-sized memory intrinsics before SelectionDAG construction. All other
memory intrinsics are inlined (the threshold is set very high for this target).
R600 doesn't support memcpy / memset / memmove library calls (previously the
illegal emission of a call to such library function triggered an error
somewhere in the code generator). X86 now emits inline loads and stores for
address spaces 256 and 257 up to the same threshold that is used for address
space 0 and reports a fatal error otherwise.
I call this a "partial fix" because there are still cases that can't be
lowered. A fatal error is reported in these cases.
[PGO] Stop using invalid char in instr variable names.
Before the patch, -fprofile-instr-generate compile will fail
if no integrated-as is specified when the file contains
any static functions (the -S output is also invalid).
This is the second try. The fix in this patch is very localized.
Only profile symbol names of profile symbols with internal
linkage are fixed up while initializer of name syms are not
changes. This means there is no format change nor version bump.
This change was discussed in D15392. It allows us to remove the fold that was added
in:
http://reviews.llvm.org/r255261
...and it will allow us to generalize this fold:
http://reviews.llvm.org/rL112232
while preserving the order of bitcast + extract that it produces and testing shows
is better handled by the backend.
Note that the existing check for "isVectorTy()" wasn't strong enough in general
and specifically because: x86_mmx. It's not a vector, but it's not vectorizable
either. So here we check VectorType::isValidElementType() directly before
proceeding with the transform.
David Majnemer [Sat, 12 Dec 2015 05:38:55 +0000 (05:38 +0000)]
[IR] Reformulate LLVM's EH funclet IR
While we have successfully implemented a funclet-oriented EH scheme on
top of LLVM IR, our scheme has some notable deficiencies:
- catchendpad and cleanupendpad are necessary in the current design
but they are difficult to explain to others, even to seasoned LLVM
experts.
- catchendpad and cleanupendpad are optimization barriers. They cannot
be split and force all potentially throwing call-sites to be invokes.
This has a noticable effect on the quality of our code generation.
- catchpad, while similar in some aspects to invoke, is fairly awkward.
It is unsplittable, starts a funclet, and has control flow to other
funclets.
- The nesting relationship between funclets is currently a property of
control flow edges. Because of this, we are forced to carefully
analyze the flow graph to see if there might potentially exist illegal
nesting among funclets. While we have logic to clone funclets when
they are illegally nested, it would be nicer if we had a
representation which forbade them upfront.
Let's clean this up a bit by doing the following:
- Instead, make catchpad more like cleanuppad and landingpad: no control
flow, just a bunch of simple operands; catchpad would be splittable.
- Introduce catchswitch, a control flow instruction designed to model
the constraints of funclet oriented EH.
- Make funclet scoping explicit by having funclet instructions consume
the token produced by the funclet which contains them.
- Remove catchendpad and cleanupendpad. Their presence can be inferred
implicitly using coloring information.
N.B. The state numbering code for the CLR has been updated but the
veracity of it's output cannot be spoken for. An expert should take a
look to make sure the results are reasonable.
Hal Finkel [Sat, 12 Dec 2015 01:47:08 +0000 (01:47 +0000)]
[PowerPC] OutStreamer cleanup in PPCAsmPrinter
We don't need to pass OutStreamer as a parameter to LowerSTACKMAP and
LowerPATCHPOINT. It is a member variable of PPCAsmPrinter, and thus, is already
available. NFC.
Chen Li [Sat, 12 Dec 2015 01:04:15 +0000 (01:04 +0000)]
[X86ISelLowering] Add additional support for multiplication-to-shift conversion.
Summary: This patch adds support of conversion (mul x, 2^N + 1) => (add (shl x, N), x) and (mul x, 2^N - 1) => (sub (shl x, N), x) if the multiplication can not be converted to LEA + SHL or LEA + LEA. LLVM has already supported this on ARM, and it should also be useful on X86. Note the patch currently only applies to cases where the constant operand is positive, and I am planing to add another patch to support negative cases after this.
Sanjay Patel [Sat, 12 Dec 2015 00:33:36 +0000 (00:33 +0000)]
[InstCombine] allow any pair of bitcasts to be combined
This change is discussed in D15392 and should allow us to effectively
revert:
http://llvm.org/viewvc/llvm-project?view=revision&revision=255261
if we canonicalize bitcasts ahead of extracts.
It should be safe to convert any pair of bitcasts into a single bitcast,
however, it was mentioned here:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20110829/127089.html
that we're not allowed to bitcast from an x86_mmx to some other types, but I'm
not seeing any failures from that, and we have regression tests in CodeGen/X86
that appear to cover all of those cases.
Some day we'll get to remove that MMX wart from LLVM IR completely?
Hal Finkel [Sat, 12 Dec 2015 00:32:00 +0000 (00:32 +0000)]
[PowerPC] Add Branch Hints for Highly-Biased Branches
This branch adds hints for highly biased branches on the PPC architecture. Even
in absence of profiling information, LLVM will mark code reaching unreachable
terminators and other exceptional control flow constructs as highly unlikely to
be reached.
Derek Schuff [Sat, 12 Dec 2015 00:18:40 +0000 (00:18 +0000)]
[WebAssembly] Update test expectations
Many tests are now passing due to eliminateFrameIndex implementation and
the list needs to be re-triaged because it unblocks other failures, and
some previous failures are different. However I'm about to churn it more
by implementing more lowering, so will wait on that.
Derek Schuff [Fri, 11 Dec 2015 23:49:46 +0000 (23:49 +0000)]
[WebAssembly] Implement prolog/epilog insertion and FrameIndex elimination
Summary:
Use the SP32 physical register as the base for FrameIndex
lowering. Update it and the __stack_pointer global var in the prolog and
epilog. Extend the mapping of virtual registers to wasm locals to
include the physical registers.
Rather than modify the target-independent PrologEpilogInserter (which
asserts that there are no virtual registers left) include a
slightly-modified copy for Wasm that does not have this assertion and
only clears the virtual registers if scavenging was needed (which of
course it isn't for wasm).
Chen Li [Fri, 11 Dec 2015 23:39:32 +0000 (23:39 +0000)]
[X86ISelLowering] Add additional support for multiplication-to-shift conversion.
Summary: This patch adds support of conversion (mul x, 2^N + 1) => (add (shl x, N), x) and (mul x, 2^N - 1) => (sub (shl x, N), x) if the multiplication can not be converted to LEA + SHL or LEA + LEA. LLVM has already supported this on ARM, and it should also be useful on X86. Note the patch currently only applies to cases where the constant operand is positive, and I am planing to add another patch to support negative cases after this.