Both the (V)CVTDQ2PD (i32 to f64) and (V)CVTUDQ2PD (u32 to f64) conversion instructions are lossless and can be safely represented as generic SINT_TO_FP/UINT_TO_FP calls instead of x86 intrinsics without affecting final codegen.
LLVM counterpart to D26686
Differential Revision: https://reviews.llvm.org/D26736
llvm-svn: 287108
These will be used to replace the masked intrinsics so that InstCombineCalls can optimize the AVX-512 variable shifts the same way it does for AVX2.
llvm-svn: 286754
After this I'll add the unmasked intrinsics to InstCombineCalls to finish making our handling of these types of shuffles consistent between AVX-512 and the legacy intrinsics.
llvm-svn: 286725
Summary:
This is the first step towards being able to add the avx512 shift by immediate intrinsics to InstCombineCalls where we aleady support the sse2 and avx2 intrinsics. We need to the unmasked versions so we can avoid having to teach InstCombineCalls that it would need to insert selects sometimes. Instead we'll just add the selects around the new instrinsics in the frontend.
This change should also enable the shift by i32 intrinsics to take a non-constant shift value just like the avx2 and sse intrinsics. This will enable us to fix PR30691 once we update clang.
Next I'll switch clang to use the new builtins. Then we'll come back to the backend and remove/autoupgrade the old intrinsics. Then I'll work on the same series for variable shifts.
Reviewers: RKSimon, zvi, delena
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D26333
llvm-svn: 286711
Masked-expand-load node represents load operation that loads a variable amount of elements from memory according to amount of "true" bits in the mask and expands the loaded elements according to their position in the mask vector.
Right now, the node is used in intrinsics for VEXPAND* instructions.
The work is done towards implementation of masked.expandload and masked.compressstore intrinsics.
Differential Revision: https://reviews.llvm.org/D25322
llvm-svn: 283694
SUBREG_TO_REG is supposed to indicate that the super register has been zeroed, but we can't prove that if we don't know where it came from.
llvm-svn: 281885
We need to bitcast the index operand to a floating point type so that it matches the result type. If not then the passthru part of the DAG will be a bitcast from the index's original type to the destination type. This makes it very difficult to match. The other option would be to add 5 sets of patterns for every other possible type.
llvm-svn: 280696
It doesn't work because we're looking for a bitcast from the v4i32 index operand to v4f32 for the passthru part of the DAG. But since the index is bitcasted from v2i64 and bitcasts fold, we actually have a bitcast from v2i64 to v4f32 in the passthru part of the DAG.
Taken from optimized output from clang's test case.
llvm-svn: 280695
Optimized lowering of BITCAST node. The BITCAST node can be replaced with COPY_TO_REG instead of KMOV.
It allows to suppress two opposite BITCAST operations and avoid redundant "movs".
Differential Revision: https://reviews.llvm.org/D23247
llvm-svn: 277958
An identity COPY like this:
%AL = COPY %AL, %EAX<imp-def>
has no semantic effect, but encodes liveness information: Further users
of %EAX only depend on this instruction even though it does not define
the full register.
Replace the COPY with a KILL instruction in those cases to maintain this
liveness information. (This reverts a small part of r238588 but this
time adds a comment explaining why a KILL instruction is useful).
llvm-svn: 274952
Craig Topper