There are two different senses in which a block can be "address-taken".
There can be a BlockAddress involved, which means we need to map the
IR-level value to some specific block of machine code. Or there can be
constructs inside a function which involve using the address of a basic
block to implement certain kinds of control flow.
Mixing these together causes a problem: if target-specific passes are
marking random blocks "address-taken", if we have a BlockAddress, we
can't actually tell which MachineBasicBlock corresponds to the
BlockAddress.
So split this into two separate bits: one for BlockAddress, and one for
the machine-specific bits.
Discovered while trying to sort out related stuff on D102817.
Differential Revision: https://reviews.llvm.org/D124697
This is a followup to D131350, which caused another problem for i64
types being split into i32 on i32 targets. This patch tries to make sure
that either Illegal types are OK, or that the element types of a
buildvector are legal and bigger than or equal to the size of the
original elements.
Differential Revision: https://reviews.llvm.org/D131883
This patch really just extends D39946 towards stores as well as loads.
While the patch is in SelectionDAGBuilder, it only applies to AVR (the
only target that supports unaligned atomic operations).
Differential Revision: https://reviews.llvm.org/D128483
The outer signext_inreg is redundant in the following:
Fold (signext_inreg (extract_subvector (zext|anyext|sext iN_value to _) _) from iN)
-> (extract_subvector (signext iN_value to iM))
Tests are precommitted and clone those by analogy from the AND case in
the same file. Add a negative test to check extension width is handled
correctly.
This patch supersedes D130700.
Differential Revision: https://reviews.llvm.org/D131503
These are guaranteed not to create undef/poison (although they may pass through) - the associated ISD::VALUETYPE node is also guaranteed never to generate poison
SimplifyMultipleUseDemandedBits shouldn't be creating general nodes like this - although we allow bitcasts, even general constant folding is avoided.
Removing it causes a number of regressions that need addressing first, but I've added a TODO for now.
This patch makes the variants of `mm*_cast*` intel intrinsics that use `shufflevector(freeze(poison), ..)` emit efficient assembly.
(These intrinsics are planned to use `shufflevector(freeze(poison), ..)` after shufflevector's semantics update; relevant thread: D103874)
To do so, this patch
1. Updates `LowerAVXCONCAT_VECTORS` in X86ISelLowering.cpp to recognize `FREEZE(UNDEF)` operand of `CONCAT_VECTOR` in addition to `UNDEF`
2. Updates X86InstrVecCompiler.td to recognize `insert_subvector` of `FREEZE(UNDEF)` vector as its first operand.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D130339
canCreateUndefOrPoison currently only handles unary ops, but we intend to change that soon - this more closely matches the pushFreezeToPreventPoisonFromPropagating behaviour where the freeze is pushed up to a single operand value, as long as all others are guaranteed not to be poison/undef.
However, pushFreezeToPreventPoisonFromPropagating would freeze all uses of the value - whilst this variant requires the frozen value to be only used in the op - we can look at generalize multiple uses later if the need arises.
Currently fcopysign for VLS vectors lowers through NEON even when the
vector width is wider than a NEON vector, causing bad codegen as the
vectors are split. This patch causes SVE to be used for these vectors
instead, giving much better codegen on wide VLS vectors.
Reviewed By: paulwalker-arm
Differential Revision: https://reviews.llvm.org/D128642
This patch adds basic support for a DAG variant of the canCreateUndefOrPoison call and updates DAGCombiner::visitFREEZE to use it, further Opcodes (including target specific Opcodes) can be handled when we have test coverage.
So far, I've left visitFREEZE to just use this for unary nodes (which currently means the existing BITCAST/FREEZE cases) - later patches will add other unary opcodes (with test coverage) and we can also refactor visitFREEZE to support a general number of operands like we do in InstCombinerImpl::pushFreezeToPreventPoisonFromPropagating.
I'm not aware of any vector test freeze coverage so the DemandedElts (and the Depth) args are not being used yet - but they are in place. Similarly we will be able to handle poison generating SDNodeFlags as and when it becomes an issue.
Part of the work for D106675 / PR50468
Differential Revision: https://reviews.llvm.org/D130646
This patch emits table lookup in expandCTTZ.
Context -
https://reviews.llvm.org/D113291 transforms set of IR instructions to
cttz intrinsic but there are some targets which does not support CTTZ or
CTLZ. Hence, I generate a table lookup in TargetLowering::expandCTTZ().
Differential Revision: https://reviews.llvm.org/D128911
FoldConstantArithmetic can fold constant vectors hidden behind bitcasts (e.g. vXi64 -> v2Xi32 on 32-bit platforms), but currently bails if either vector contains undef elements. These undefs can often occur due to SimplifyDemandedBits/VectorElts calls recognising that the upper bits are often unnecessary (e.g. funnel-shift/rotate implicit-modulo and AND masks).
This patch adds a basic 'FoldValueWithUndef' handler that will attempt to constant fold if one or both of the ops are undef - so far this just handles the AND and MUL cases where we always fold to zero.
The RISCV codegen increase is interesting - it looks like the BUILD_VECTOR lowering was loading a constant pool entry but now (with all elements defined constant) it can materialize the constant instead?
Differential Revision: https://reviews.llvm.org/D130839
D129150 added a combine from shuffles to And that creates a BUILD_VECTOR
of constant elements. We need to ensure that the elements are of a legal
type, to prevent asserts during lowering.
Fixes#56970.
Differential Revision: https://reviews.llvm.org/D131350
The function `handleDebugValue` has custom logic to handle certain kinds
constants, namely integers, floats and null pointers. However, it does
not handle constant pointers created from IntToPtr ConstantExpressions.
This patch addresses the issue by replacing the Constant with its
integer operand.
A similar bug was addressed for GlobalISel in D130642.
Reviewed By: aprantl, #debug-info
Differential Revision: https://reviews.llvm.org/D130908
This patch ensures consistency in the construction of FP_ROUND nodes
such that they always use ISD::TargetConstant instead of ISD::Constant.
This additionally fixes a bug in the AArch64 SVE backend where patterns
were matching against TargetConstant nodes and sometimes failing when
passed a Constant node.
Reviewed By: paulwalker-arm
Differential Revision: https://reviews.llvm.org/D130370
matchRotateSub is given shift amounts that will already have stripped any/zero-extend nodes from - so make sure those values are wide enough to take a mask.
Eliminate an AND by redefining an anyext|sext|zext.
(and (extract_subvector (anyext|sext|zext v) _) iN_mask)
=> (extract_subvector (zeroext_iN v))
Differential Revision: https://reviews.llvm.org/D130782
This belongs to a series of patches which try to solve the thread
identification problem in coroutines. See
https://discourse.llvm.org/t/address-thread-identification-problems-with-coroutine/62015
for a full background.
The problem consists of two concrete problems: TLS variable and readnone
functions. This patch tries to convert the TLS problem to readnone
problem by converting the access of TLS variable to an intrinsic which
is marked as readnone.
The readnone problem would be addressed in following patches.
Reviewed By: nikic, jyknight, nhaehnle, ychen
Differential Revision: https://reviews.llvm.org/D125291
Eli Friedman