Enable partial and runtime loop unrolling for NVPTX backend via
TTI::UnrollingPreferences with a small threshold. This partially unrolls
small loops which are often unrolled by the PTX to SASS compiler
and unrolling earlier can be beneficial.
llvm-svn: 242049
The two-address instruction pass will convert these back to v_mad_f32
if necessary.
Differential Revision: http://reviews.llvm.org/D11060
llvm-svn: 242038
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
llvm-svn: 242037
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
llvm-svn: 242023
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.
llvm-svn: 241996
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
llvm-svn: 241989
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.
llvm-svn: 241985
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.
llvm-svn: 241984
Disallow all mutation of `MCSubtargetInfo` expect the feature bits.
Besides deleting the assignment operators -- which were dead "code" --
this restricts `InitMCProcessorInfo()` to subclass initialization
sequences, and exposes a new more limited function called
`setDefaultFeatures()` for use by the ARMAsmParser `.cpu` directive.
There's a small functional change here: ARMAsmParser used to adjust
`MCSubtargetInfo::CPUSchedModel` as a side effect of calling
`InitMCProcessorInfo()`, but I've removed that suspicious behaviour.
Since the AsmParser shouldn't be doing any scheduling, there shouldn't
be any observable change...
llvm-svn: 241961
Most loads and stores are derived from pointers derived from
a kernel argument load inserted during argument lowering.
This was just using the EntryToken chain for the argument loads,
and any users of these loads were also on the EntryToken chain.
Return the chain of the lowered argument load so that dependent loads
end up on the correct chain.
No test since I'm not aware of any case where this actually
broke.
llvm-svn: 241960
Force all creators of `MCSubtargetInfo` to immediately initialize it,
merging the default constructor and the initializer into an initializing
constructor. Besides cleaning up the code a little, this makes it clear
that the initializer is never called again later.
Out-of-tree backends need a trivial change: instead of calling:
auto *X = new MCSubtargetInfo();
InitXYZMCSubtargetInfo(X, ...);
return X;
they should call:
return createXYZMCSubtargetInfoImpl(...);
There's no real functionality change here.
llvm-svn: 241957
Remove all calls to `MCSubtargetInfo::InitCPUSched()` and merge its body
into the only relevant caller, `MCSubtargetInfo::InitMCProcessorInfo()`.
We were only calling the former after explicitly calling the latter with
the same CPU; it's confusing to have both methods exposed.
Besides a minor (surely unmeasurable) speedup in ARM and X86 from
avoiding running the logic twice, no functionality change.
llvm-svn: 241956
Fixes PR23804: assertion failure in emitPrologue in the case of a
function with an empty frame and a dynamic alloca that needs stack
realignment. This is a typical case for AddressSanitizer.
llvm-svn: 241943
Summary:
Following the discussion on r241884, it's more reasonable to assume that a
target has no vector registers by default instead of letting every such
target overrides getNumberOfRegisters.
Therefore, this patch modifies BasicTTIImpl::getNumberOfRegisters to
return 0 when Vector is true, and partially reverts r241884 which
modifies NVPTXTTIImpl::getNumberOfRegisters.
It also fixes a performance bug in LoopVectorizer. Even if a target has
no vector registers, vectorization may still help ILP. So, we need both
checks to be false before disabling loop vectorization all together.
Reviewers: hfinkel
Subscribers: llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11108
llvm-svn: 241942
This commit factors out common code from MergeBaseUpdateLoadStore() and
MergeBaseUpdateLSMultiple() and introduces a new function
MergeBaseUpdateLSDouble() which merges adds/subs preceding/following a
strd/ldrd instruction into an strd/ldrd instruction with writeback where
possible.
Differential Revision: http://reviews.llvm.org/D10676
llvm-svn: 241928
Summary:
This code is based on AArch64 for modern backend good practice, and NVPTX for
virtual ISA concerns.
Reviewers: sunfish
Subscribers: aemerson, llvm-commits, jfb
Differential Revision: http://reviews.llvm.org/D11070
llvm-svn: 241923
Summary:
The target frame lowering's concrete type is always known in RegisterInfo, yet it's only sometimes devirtualized through a static_cast. This change adds an auto-generated static function <Target>GenRegisterInfo::getFrameLowering(const MachineFunction &MF) which does this devirtualization, and uses this function in all targets which can.
This change was suggested by sunfish in D11070 for WebAssembly, I figure that I may as well improve the other targets while I'm here.
Subscribers: sunfish, ted, llvm-commits, jfb
Differential Revision: http://reviews.llvm.org/D11093
llvm-svn: 241921
This improves the logic in several ways and is a preparation for
followup patches:
- First perform an analysis and create a list of merge candidates, then
transform. This simplifies the code in that you have don't have to
care to much anymore that you may be holding iterators to
MachineInstrs that get removed.
- Analyze/Transform basic blocks in reverse order. This allows to use
LivePhysRegs to find free registers instead of the RegisterScavenger.
The RegisterScavenger will become less precise in the future as it
relies on the deprecated kill-flags.
- Return the newly created node in MergeOps so there's no need to look
around in the schedule to find it.
- Rename some MBBI iterators to InsertBefore to make their role clear.
- General code cleanup.
Differential Revision: http://reviews.llvm.org/D10140
llvm-svn: 241920
Summary:
Without this patch, LoopVectorizer in certain cases (see loop-vectorize.ll)
produces code with complex control flow which hurts later optimizations. Since
NVPTX doesn't have vector registers in LLVM's sense
(NVPTXTTI::getRegisterBitWidth(true) == 32), we for now declare no vector
registers to effectively disable loop vectorization.
Reviewers: jholewinski
Subscribers: jingyue, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11089
llvm-svn: 241884
Apparently this is important, otherwise _except_handler3 assumes that
the registration node is corrupted and ignores it.
Also fix a bug in WinEHPrepare where we would insert code after a
terminator instruction.
llvm-svn: 241877
The runtime does not restore CSRs when transferring control back to the
function handling the exception. According to the experts on IRC, LLVM's
register allocator has no way to model register clobbers that only
happen on one edge of the CFG. For now, don't worry about trying to use
the meager three CSRs available on 32-bit X86 and just say that such
invokes preserve nothing.
llvm-svn: 241865
This patch allows the read_register and write_register intrinsics to
read/write the RBP/EBP registers on X86 iff the targeted register is
the frame pointer for the containing function.
Differential Revision: http://reviews.llvm.org/D10977
llvm-svn: 241827
Summary: If shift amount is a constant value > 64 bit it is handled incorrectly during type legalization and X86 lowering. This patch the type of shift amount argument in function DAGTypeLegalizer::ExpandShiftByConstant from unsigned to APInt.
Reviewers: nadav, majnemer, sanjoy, RKSimon
Subscribers: RKSimon, llvm-commits
Differential Revision: http://reviews.llvm.org/D10767
llvm-svn: 241806
Benjamin Kramer