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r243057 | spatel | 2015-07-23 15:56:53 -0700 (Thu, 23 Jul 2015) | 16 lines
fix crash in machine trace metrics due to processing dbg_value instructions (PR24199)
The test in PR24199 ( https://llvm.org/bugs/show_bug.cgi?id=24199 ) crashes because machine
trace metrics was not ignoring dbg_value instructions when calculating data dependencies.
The machine-combiner pass asks machine trace metrics to calculate an instruction trace,
does some reassociations, and calls MachineInstr::eraseFromParentAndMarkDBGValuesForRemoval()
along with MachineTraceMetrics::invalidate(). The dbg_value instructions have their operands
invalidated, but the instructions are not expected to be deleted.
On a subsequent loop iteration of the machine-combiner pass, machine trace metrics would be
called again and die while accessing the invalid debug instructions.
Differential Revision: http://reviews.llvm.org/D11423
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r243638 | vkalintiris | 2015-07-30 05:39:33 -0700 (Thu, 30 Jul 2015) | 12 lines
[mips][FastISel] Remove hidden mips-fast-isel option.
Summary:
This hidden option would disable code generation through FastISel by
default. It was removed from the available options and from the
Fast-ISel tests that required it in order to run the tests.
Reviewers: dsanders
Subscribers: qcolombet, llvm-commits
Differential Revision: http://reviews.llvm.org/D11610
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r243640 | vkalintiris | 2015-07-30 06:13:09 -0700 (Thu, 30 Jul 2015) | 5 lines
[mips] Fix out-of-date debug information in test file.
Update the debug info in the check-lines because the change in r243638
introduced a constant initialization before the prologue's end as part
of a register spill.
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r243636 | vkalintiris | 2015-07-30 04:51:44 -0700 (Thu, 30 Jul 2015) | 34 lines
[mips][FastISel] Apply only zero-extension to constants prior to their materialization.
Summary:
Previously, we would sign-extend non-boolean negative constants and
zero-extend otherwise. This was problematic for PHI instructions with
negative values that had a type with bitwidth less than that of the
register used for materialization.
More specifically, ComputePHILiveOutRegInfo() assumes the constants
present in a PHI node are zero extended in their container and
afterwards deduces the known bits.
For example, previously we would materialize an i16 -4 with the
following instruction:
addiu $r, $zero, -4
The register would end-up with the 32-bit 2's complement representation
of -4. However, ComputePHILiveOutRegInfo() would generate a constant
with the upper 16-bits set to zero. The SelectionDAG builder would use
that information to generate an AssertZero node that would remove any
subsequent trunc & zero_extend nodes.
In theory, we should modify ComputePHILiveOutRegInfo() to consult
target-specific hooks about the way they prefer to materialize the
given constants. However, git-blame reports that this specific code
has not been touched since 2011 and it seems to be working well for every
target so far.
Reviewers: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11592
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r243485 | vkalintiris | 2015-07-28 14:43:31 -0700 (Tue, 28 Jul 2015) | 12 lines
[mips][FastISel] Fix call lowering by bailing out on "fastcc" calls.
Summary:
Currently, we support only the MIPS O32 ABI calling convention for call
lowering. With this change we avoid using the O32 calling convetion for
lowering calls marked as using the fast calling convention.
Reviewers: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11515
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r243519 | wschmidt | 2015-07-29 07:31:57 -0700 (Wed, 29 Jul 2015) | 14 lines
[PPC] Fix PR24216: Don't generate splat for misaligned shuffle mask
Given certain shuffle-vector masks, LLVM emits splat instructions
which splat the wrong bytes from the source register. The issue is
that the function PPC::isSplatShuffleMask() in PPCISelLowering.cpp
does not ensure that the splat pattern found is requesting bytes that
are aligned on an EltSize boundary. This patch detects this situation
as not a valid splat mask, resulting in a permute being generated
instead of a splat.
Patch and test case by Tyler Kenney, cleaned up a bit by me.
This is a simple bug fix that would be good to incorporate into 3.7.
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r243500 | spatel | 2015-07-28 16:28:22 -0700 (Tue, 28 Jul 2015) | 16 lines
ignore duplicate divisor uses when transforming into reciprocal multiplies (PR24141)
PR24141: https://llvm.org/bugs/show_bug.cgi?id=24141
contains a test case where we have duplicate entries in a node's uses() list.
After r241826, we use CombineTo() to delete dead nodes when combining the uses into
reciprocal multiplies, but this fails if we encounter the just-deleted node again in
the list.
The solution in this patch is to not add duplicate entries to the list of users that
we will subsequently iterate over. For the test case, this avoids triggering the
combine divisors logic entirely because there really is only one user of the divisor.
Differential Revision: http://reviews.llvm.org/D11345
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r243361 | spatel | 2015-07-27 17:48:32 -0700 (Mon, 27 Jul 2015) | 17 lines
fix invalid load folding with SSE/AVX FP logical instructions (PR22371)
This is a follow-up to the FIXME that was added with D7474 ( http://reviews.llvm.org/rL229531 ).
I thought this load folding bug had been made hard-to-hit, but it turns out to be very easy
when targeting 32-bit x86 and causes a miscompile/crash in Wine:
https://bugs.winehq.org/show_bug.cgi?id=38826https://llvm.org/bugs/show_bug.cgi?id=22371#c25
The quick fix is to simply remove the scalar FP logical instructions from the load folding table
in X86InstrInfo, but that causes us to miss load folds that should be possible when lowering fabs,
fneg, fcopysign. So the majority of this patch is altering those lowerings to use *vector* FP
logical instructions (because that's all x86 gives us anyway). That lets us do the load folding
legally.
Differential Revision: http://reviews.llvm.org/D11477
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r243294 | mareko | 2015-07-27 11:16:08 -0700 (Mon, 27 Jul 2015) | 9 lines
AMDGPU: don't match vgpr loads for constant loads
Author: Dave Airlie <airlied@redhat.com>
In order to implement indirect sampler loads, we don't
want to match on a VGPR load but an SGPR one for constants,
as we cannot feed VGPRs to the sampler only SGPRs.
this should be applicable for llvm 3.7 as well.
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(r242742 is the interesting patch here, but I picked the others too to get a clean
merge since there's been some back-and-forth on this file.)
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r242733 | matze | 2015-07-20 16:17:14 -0700 (Mon, 20 Jul 2015) | 3 lines
Revert "ARM: Use SpecificBumpPtrAllocator to fix leak introduced in r241920"
This reverts commit r241951. It caused http://llvm.org/PR24190
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r242734 | matze | 2015-07-20 16:17:16 -0700 (Mon, 20 Jul 2015) | 3 lines
Revert "ARMLoadStoreOpt: Merge subs/adds into LDRD/STRD; Factor out common code"
This reverts commit r241928. This caused http://llvm.org/PR24190
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r242735 | matze | 2015-07-20 16:17:20 -0700 (Mon, 20 Jul 2015) | 3 lines
Revert "ARMLoadStoreOptimizer: Create LDRD/STRD on thumb2"
This reverts commit r241926. This caused http://llvm.org/PR24190
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r242742 | matze | 2015-07-20 17:18:59 -0700 (Mon, 20 Jul 2015) | 7 lines
ARMLoadStoreOptimizer: Create LDRD/STRD on thumb2
Re-apply r241926 with an additional check that r13 and r15 are not used
for LDRD/STRD. See http://llvm.org/PR24190. This also already includes
the fix from r241951.
Differential Revision: http://reviews.llvm.org/D10623
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r242673 | tstellar | 2015-07-20 07:28:41 -0700 (Mon, 20 Jul 2015) | 11 lines
AMDGPU/SI: Add VI patterns to select FLAT instructions for global memory ops
Summary:
The MUBUF addr64 bit has been removed on VI, so we must use FLAT
instructions when the pointer is stored in VGPRs.
Reviewers: arsenm
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11067
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r242442 | wschmidt | 2015-07-16 14:14:07 -0700 (Thu, 16 Jul 2015) | 14 lines
[PowerPC] v4i32 is a VSRCRegClass
I was looking at some vector code generation and kept seeing
unnecessary vector copies into the Altivec half of the VSX registers.
I discovered that we overlooked v4i32 when adding the register classes
for VSX; we only added v4f32 and v2f64. This means that anything that
canonicalizes into v4i32 (which is a LOT of stuff) ends up being
forced into VRRC on its way to VSRC.
The fix is one line. The rest of the patch is fixing up some test
cases whose code generation has changed as a result.
This seems like it would be a good candidate for backport to 3.7.
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r242239 | hfinkel | 2015-07-14 15:53:11 -0700 (Tue, 14 Jul 2015) | 4 lines
[PowerPC] Support symbolic targets in patchpoints
Follow-up r235483, with the corresponding support in PPC. We use a regular call
for symbolic targets (because they're much cheaper than indirect calls).
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We used to take the address specified as the direct target of the patchpoint
and did no TOC-pointer handling. This, however, as not all that useful,
because MCJIT tends to create a lot of modules, and they have their own TOC
sections. Thus, to call from the generated code to other generated code, you
really need to switch TOC pointers. Make this work as expected, and under
ELFv1, tread the address as the function descriptor address so that the correct
TOC pointer can be loaded.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242217 91177308-0d34-0410-b5e6-96231b3b80d8
PowerPC uses itineraries to describe processor pipelines (and dispatch-group
restrictions for P7/P8 cores). Unfortunately, the target-independent
implementation of TII.getInstrLatency calls ItinData->getStageLatency, and that
looks for the largest cycle count in the pipeline for any given instruction.
This, however, yields the wrong answer for the PPC itineraries, because we
don't encode the full pipeline. Because the functional units are fully
pipelined, we only model the initial stages (there are no relevant hazards in
the later stages to model), and so the technique employed by getStageLatency
does not really work. Instead, we should take the maximum output operand
latency, and that's what PPCInstrInfo::getInstrLatency now does.
This caused some test-case churn, including two unfortunate side effects.
First, the new arrangement of copies we get from function parameters now
sometimes blocks VSX FMA mutation (a FIXME has been added to the code and the
test cases), and we have one significant test-suite regression:
SingleSource/Benchmarks/BenchmarkGame/spectral-norm
56.4185% +/- 18.9398%
In this benchmark we have a loop with a vectorized FP divide, and it with the
new scheduling both divides end up in the same dispatch group (which in this
case seems to cause a problem, although why is not exactly clear). The grouping
structure is hard to predict from the bottom of the loop, and there may not be
much we can do to fix this.
Very few other test-suite performance effects were really significant, but
almost all weakly favor this change. However, in light of the issues
highlighted above, I've left the old behavior available via a
command-line flag.
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Convert logical operations on general-purpose registers to the correspon-
ding operations on predicate registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242186 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Before this change, personality directives were not emitted
if there was no invoke left in the function (of course until
recently this also meant that we couldn't know what
the personality actually was). This patch forces personality directives
to still be emitted, unless it is known to be a noop in the absence of
invokes, or the user explicitly specified `nounwind` (and not
`uwtable`) on the function.
Reviewers: majnemer, rnk
Subscribers: rnk, llvm-commits
Differential Revision: http://reviews.llvm.org/D10884
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This can be done only with moves which theoretically
will optimize better later.
Although this transform increases the instruction count,
it should be code size / cycle count neutral in the worst
VALU case. It also seems to slightly improve a couple
of testcases due to other DAG combines this exposes.
This is probably slightly worse for the SALU case, so
it might be better to handle this during moveToVALU,
although then you lose some simplifications like
the load width reducing in the simple testcase.
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If the read2 produced was supposed to be writing into a
super register, it would use the wrong subregister indices.
Fix this by inserting copies, so we only ever write to a vreg_64.
Run the register coalescer again to clean this up, although this
isn't ideal and often does result in an extra move.
Also remove the assert that offset1 > offset0.
There isn't a real reason to not allow this other than a minor
convenience in the compiler, and it doesn't seem worth the effort
of avoiding it.
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The ones committed were orthogonal to the change and would have passed before
that revision. What it *did* do was prevent an assertion failure when
generating object files.
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This changes TargetFrameLowering::processFunctionBeforeCalleeSavedScan():
- Rename the function to determineCalleeSaves()
- Pass a bitset of callee saved registers by reference, thus avoiding
the function-global PhysRegUsed bitset in MachineRegisterInfo.
- Without PhysRegUsed the implementation is fine tuned to not save
physcial registers which are only read but never modified.
Related to rdar://21539507
Differential Revision: http://reviews.llvm.org/D10909
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Generate extract instructions (via intrinsics) before the DAG combiner
folds shifts into unrecognizable forms.
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- Factor out code to query and modify the sign bit of a floatingpoint
value as an integer. This also works if none of the targets integer
types is big enough to hold all bits of the floatingpoint value.
- Legalize FABS(x) as FCOPYSIGN(x, 0.0) if FCOPYSIGN is available,
otherwise perform bit manipulation on the sign bit. The previous code
used "x >u 0 ? x : -x" which is incorrect for x being -0.0! It also
takes 34 instructions on ARM Cortex-M4. With this patch we only
require 5:
vldr d0, LCPI0_0
vmov r2, r3, d0
lsrs r2, r3, #31
bfi r1, r2, #31, #1
bx lr
(This could be further improved if the compiler would recognize that
r2, r3 is zero).
- Only lower FCOPYSIGN(x, y) = sign(x) ? -FABS(x) : FABS(x) if FABS is
available otherwise perform bit manipulation on the sign bit.
- Perform the sign(x) test by masking out the sign bit and comparing
with 0 rather than shifting the sign bit to the highest position and
testing for "<s 0". For x86 copysignl (on 80bit values) this gets us:
testl $32768, %eax
rather than:
shlq $48, %rax
sets %al
testb %al, %al
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This commit serializes the sub register indices from the register machine
operands.
Reviewers: Duncan P. N. Exon Smith
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This patch allows VSX swap optimization to succeed more frequently.
Specifically, it is concerned with common code sequences that occur
when copying a scalar floating-point value to a vector register. This
patch currently handles cases where the floating-point value is
already in a register, but does not yet handle loads (such as via an
LXSDX scalar floating-point VSX load). That will be dealt with later.
A typical case is when a scalar value comes in as a floating-point
parameter. The value is copied into a virtual VSFRC register, and
then a sequence of SUBREG_TO_REG and/or COPY operations will convert
it to a full vector register of the class required by the context. If
this vector register is then used as part of a lane-permuted
computation, the original scalar value will be in the wrong lane. We
can fix this by adding a swap operation following any widening
SUBREG_TO_REG operation. Additional COPY operations may be needed
around the swap operation in order to keep register assignment happy,
but these are pro forma operations that will be removed by coalescing.
If a scalar value is otherwise directly referenced in a computation
(such as by one of the many XS* vector-scalar operations), we
currently disable swap optimization. These operations are
lane-sensitive by definition. A MentionsPartialVR flag is added for
use in each swap table entry that mentions a scalar floating-point
register without having special handling defined.
A common idiom for PPC64LE is to convert a double-precision scalar to
a vector by performing a splat operation. This ensures that the value
can be referenced as V[0], as it would be for big endian, whereas just
converting the scalar to a vector with a SUBREG_TO_REG operation
leaves this value only in V[1]. A doubleword splat operation is one
form of an XXPERMDI instruction, which takes one doubleword from a
first operand and another doubleword from a second operand, with a
two-bit selector operand indicating which doublewords are chosen. In
the general case, an XXPERMDI can be permitted in a lane-swapped
region provided that it is properly transformed to select the
corresponding swapped values. This transformation is to reverse the
order of the two input operands, and to reverse and complement the
bits of the selector operand (derivation left as an exercise to the
reader ;).
A new test case that exercises the scalar-to-vector and generalized
XXPERMDI transformations is added as CodeGen/PowerPC/swaps-le-5.ll.
The patch also requires a change to CodeGen/PowerPC/swaps-le-3.ll to
use CHECK-DAG instead of CHECK for two independent instructions that
now appear in reverse order.
There are two small unrelated changes that are added with this patch.
First, the XXSLDWI instruction was incorrectly omitted from the list
of lane-sensitive instructions; this is now fixed. Second, I observed
that the same webs were being rejected over and over again for
different reasons. Since it's sufficient to reject a web only once, I
added a check for this to speed up the compilation time slightly.
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The outlined funclets call intrinsics which reference labels from the
LSDA. This situation can easily arise in small functions with a single
cleanup at -O0, where Clang marks a definition as nounwind, and then
WinEHPrepare "discovers" that the landingpad is dead by accident and
deletes it.
We now need to ask the LLVM IR Function for it's personality directly,
rather than going through MachineModuleInfo.
Fixes PR23892.
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This commit serializes the fixed stack objects, including fixed spill slots.
The fixed stack objects are serialized using a YAML sequence of YAML inline
mappings. Each mapping has the object's ID, type, size, offset, and alignment.
The objects that aren't spill slots also serialize the isImmutable and isAliased
flags.
The fixed stack objects are a part of the machine function's YAML mapping.
Reviewers: Duncan P. N. Exon Smith
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It had accidently accepted a symbol+offset value (and emitted
incorrect code for it, keeping only the offset part) instead of
properly reporting the constraint as invalid.
Differential Revision: http://reviews.llvm.org/D11039
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The 64/128-bit vector types are legal if NEON instructions are
available. However, there was no matching patterns for @llvm.cttz.*()
intrinsics and result in fatal error.
This commit fixes the problem by lowering cttz to:
a. ctpop((x & -x) - 1)
b. width - ctlz(x & -x) - 1
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In this patch I have only encoding. Intrinsics and DAG lowering will be in the next patch.
I temporary removed the old intrinsics test (just to split this patch).
Half types are not covered here.
Differential Revision: http://reviews.llvm.org/D11134
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Register r12 ('ip') is used by GCC for this purpose
and hence is used here. As discussed on the GCC mailing
list, the register choice is an ABI issue and so
choosing the same register as GCC means
__builtin_call_with_static_chain is compatible.
A similar patch has just gone in the AArch64 backend,
so this is just the ARM counterpart, following the same
discussion.
Patch by Stephen Cross.
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While the v4i32 shl operation is already vectorized using a cvttps2dq/pmulld pattern, the lshr/ashr opeations are still scalarized.
This patch adds vectorization support for non-uniform v4i32 shift operations - it splats constant shift amounts to allow them to use the immediate sse shift instructions, or extracts/zero-extends non-constant shift amounts. The individual results are then blended together.
Differential Revision: http://reviews.llvm.org/D11063
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r238842 added the TargetRecip system for controlling use of reciprocal
estimates for sqrt and division using a set of parameters that can be set by
the frontend. Clang now supports a sophisticated -mrecip option, and this will
allow that option to effectively control the relevant code-generation
functionality of the PPC backend.
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This adds support for the 'nest' attribute, which allows the static chain
register to be set for functions calls under non-Darwin PPC/PPC64 targets. r11
is the chain register (which the PPC64 ELF ABI calls the "environment
pointer"). For indirect calls under PPC64 ELFv1, this would normally be loaded
from the function descriptor, but providing an explicit 'nest' parameter will
override that process and use the value provided.
This allows __builtin_call_with_static_chain to work as expected on PowerPC.
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