FoldSetCC() returns UNDEF in a number of cases. However, the SetCC
result must follow BooleanContents. Unless the type is a
pre-legalization i1 or we have UndefinedBooleanContents, the use of
UNDEF will not uphold the requirement that the top bits are either
zero or match the low bit. In such cases, return zero instead.
Fixes https://github.com/llvm/llvm-project/issues/63055.
Differential Revision: https://reviews.llvm.org/D151883
Given an insert of a scalar load into a vector shuffle with mask
u,0,1,2,3,4,5,6 or 1,2,3,4,5,6,7,u (depending on the insert index),
it can be more profitable to convert to a single load and avoid the
shuffles. This adds a DAG combine for it, providing the new load is
still fast.
Differential Revision: https://reviews.llvm.org/D151029
This exposed a miscompile due to incorrect flag preservation in
integer type legalization, which has been fixed in D151472.
-----
This patch is a continuation of D150110. It separates the cases for
ADD and SUB into their own cases so that computeForAddSub can be
directly called and the NSW flag passed. This allows better
optimization when the NSW flag is enabled, and allows fixing up the
TODO that was there previously in SimplifyDemandedBits.
Differential Revision: https://reviews.llvm.org/D150769
This reverts commit 9b92f70d4758f75903ce93feaba5098130820d40. The issue
with the re-applied change was an implicit truncation due to the
multiplication. Although the operations were converted to `APInt`, the
values were implicitly converted to `long` due to the typing rules.
Fixes: #59594
Differential Revision: https://reviews.llvm.org/D140347
The generic implementation is umin(TC, VF * vscale).
Lowering to vsetvli for RISC-V will come in a future patch.
This patch is a pre-requisite to be able to CodeGen vectorized code from
D99750.
Reviewed By: reames, frasercrmck
Differential Revision: https://reviews.llvm.org/D149916
This patch is a continuation of D150110. It separates the cases for
ADD and SUB into their own cases so that computeForAddSub can be
directly called and the NSW flag passed. This allows better
optimization when the NSW flag is enabled, and allows fixing up the
TODO that was there previously in SimplifyDemandedBits.
Differential Revision: https://reviews.llvm.org/D150769
Define intersectWith and unionWith as two complementary ways of
combining KnownBits. The names are chosen for consistency with
ConstantRange.
Deprecate commonBits as a synonym for intersectWith.
Differential Revision: https://reviews.llvm.org/D150443
The current logic is pretty limitted unless the `Op` is a
constant. This at least covers more obvious cases.
Reviewed By: craig.topper, foad
Differential Revision: https://reviews.llvm.org/D149196
Both of these functions recursively call themselves so it makes sense
to limit that upper bound.
Differential Revision: https://reviews.llvm.org/D149195
We were missing any support for ISD::INTRINSIC_W_CHAIN/INTRINSIC_VOID
used for memory operations.
For ISD::PREFETCH and target memory nodes we didn't add the subclass
data.
This patch handles all MemIntrinsicSDNode in one place and adds the
missing subclass data.
Note. Unlike load/stores we don't add the memory VT in AddNodeIDCustom or getMemIntrinsicNode. Not sure why.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D150387
For constant BUILD_VECTORs the operands need to be legal types. This can mean
that when the number of sign bits is calculated it may look that the entire
constant and inefficiently produce less sign bits than it could. For example i8
vectors could use i32 elements, for which 0x000000ff would be incorrectly
limited to 1 sign bit as the original value has 24 sign bits. This makes it
look at the constant directly, truncated to the correct type for the element so
that it can correctly return 8.
Differential Revision: https://reviews.llvm.org/D149956
Add basic computeOverflowForSignedAdd helper to recognise that sadd overflow can't occur if both operands have more that one sign bit.
Add computeOverflowForAdd wrapper that calls computeOverflowForSignedAdd/computeOverflowForUnsignedAdd depending on the IsSigned argument, and use this in DAGCombiner::visitADDO
This is rework of;
- rG13e77db2df94 (r328395; MVT)
Since `LowLevelType.h` has been restored to `CodeGen`, `MachinveValueType.h`
can be restored as well.
Depends on D148767
Differential Revision: https://reviews.llvm.org/D149024
The only way known bits could help identify a known power of two is if
it knows exactly which power of two it is, i.e. if it is a known
constant. But in that case the value should have been simplified to a
constant already. So save some compile time by not calling
computeKnownBits.
Differential Revision: https://reviews.llvm.org/D149325
This patch replaces the uses of PointerUnion.is function by llvm::isa,
PointerUnion.get function by llvm::cast, and PointerUnion.dyn_cast by
llvm::dyn_cast_if_present. This is according to the FIXME in
the definition of the class PointerUnion.
This patch does not remove them as they are being used in other
subprojects.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D148449
Similar to the existing SelectionDAG::SplitVector helper, this helper creates the EXTRACT_ELEMENT nodes for the LO/HI halves of the scalar source.
Differential Revision: https://reviews.llvm.org/D147264
The patch customized lower vector type ISD::STRICT_FP_ROUND to RISCVISD::STRICT_FP_ROUND.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D147113
Extend the existing store(load()) removal code to account for intermediate truncates that some targets won't remove with canCombineTruncStore - we only care about the load/store MemoryVT.
Fixes regression from D146121
Switch DAGISel over to UniformityAnalysis, which was one of the last remaining users of the DivergenceAnalysis.
No explosions seen during internal testing so this looks like a smooth transition.
Reviewed By: sameerds
Differential Revision: https://reviews.llvm.org/D145918
Switch DAGISel over to UniformityAnalysis, which was one of the last remaining users of the DivergenceAnalysis.
No explosions seen during internal testing so this looks like a smooth transition.
Reviewed By: sameerds
Differential Revision: https://reviews.llvm.org/D145918
The patch mainly does two things. The first is allowing scalable vector
ISD::STRICT_FP_EXTEND. The second is making RISC-V customized lower
strict_fpextend to riscv_strict_fpextend_vl, the strict version of
riscv_fpextend_vl.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D145548
It turns out that there are relatively trivial, albeit rare, cases that
require a MaxDepth of more than 16 (see added test). However, we want to
avoid having to rely on a large fixed MaxDepth.
Since these cases are relatively rare, apply the following strategy:
1. Start with a low MaxDepth of 16 - if the entry node was not
reached, we can return (the common case).
2. If the entry node was reached, exponentially increase MaxDepth up
to some large limit that should cover all cases and guard against
stack exhaustion.
This retains the better performance with a low MaxDepth in the common
case, and in complex cases backs off and retries. On a whole, this is
preferable vs. starting with a large MaxDepth which would unnecessarily
penalize the common case where a low MaxDepth is sufficient.
Reviewed By: dvyukov
Differential Revision: https://reviews.llvm.org/D145386
Move MaxDepth into the lambda, since it is not needed outside. This
fixes some compilers that complain about missing capture:
error C3493: 'MaxDepth' cannot be implicitly captured because no
default capture mode has been specified
Fixes: f693932fbea7 ("[SelectionDAG] Transitively copy NodeExtraInfo on RAUW")
During legalization of the SelectionDAG, some nodes are replaced with
arch-specific nodes. These may be complex nodes, where the root node no
longer corresponds to the node that should carry the extra info.
Fix the issue by copying extra info to the new node and all its new
transitive operands during RAUW. See code comments for more details.
This fixes the remaining pcsections-atomics.ll tests on X86.
v2: Optimize copyExtraInfo() deep copy. For now we assume that only
NodeExtraInfo that have PCSections set require deep copy. Furthermore,
limit the depth of graph search while pre-populating the visited set,
assuming the to-be-replaced subgraph 'From' has limited complexity. An
assertion catches if the maximum depth needs to be increased.
Reviewed By: dvyukov
Differential Revision: https://reviews.llvm.org/D144677
During legalization of the SelectionDAG, some nodes are replaced with
arch-specific nodes. These may be complex nodes, where the root node no
longer corresponds to the node that should carry the extra info.
Fix the issue by copying extra info to the new node and all its new
transitive operands during RAUW. See code comments for more details.
This fixes the remaining pcsections-atomics.ll tests on X86.
Reviewed By: dvyukov
Differential Revision: https://reviews.llvm.org/D144677
One of the cleanups necessary for D136529 - another being how we're going to handle moving freeze through multiple result nodes (like uaddo and subcarry)
The patch tries to solve duplicated combine work for vp sdnodes. The idea is to
introduce MatchConext that verifies specific patterns and generate specific node
infromation. There is two MatchConext in DAGCombiner. EmptyMatcher is for
normal nodes and VPMatcher is for vp nodes.
The idea of this patch is come form Simon Moll's proposal [0]. I only fixed some
minor issues and added few new features in this patch.
[0]: c38a14484a
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D141891
