llvm-project.git/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.cpp, branch users/nico/python-2

[SelectionDAG] Virtualize isTargetStrictFPOpcode / isTargetMemoryOpcode (#119969)

2024-12-21T02:29:51+00:00

With this change, targets are no longer required to put memory / strict-fp opcodes after special
`ISD::FIRST_TARGET_MEMORY_OPCODE`/`ISD::FIRST_TARGET_STRICTFP_OPCODE` markers.
This will also allow autogenerating `isTargetMemoryOpcode`/`isTargetStrictFPOpcode (#119709).

Pull Request: https://github.com/llvm/llvm-project/pull/119969

[SystemZ] Use getSignedConstant() where necessary (#117181)

2024-11-25T08:47:49+00:00

This will avoid assertion failures once we disable implicit truncation
in getConstant().

Inside adjustSubwordCmp() I ended up suppressing the issue with an
explicit cast, because this code deals with a mix of unsigned and signed
immediates.

[SystemZ] Use llvm::bit_floor (NFC)

2023-01-25T06:10:03+00:00

If x is known to be nonzero, findLastSet(x) returns the index of the
highest set bit counting from the LSB, so 1 << findLastSet(x) is the
same as llvm::bit_floor(x).

[NFC] Deprecate SelectionDag functions taking Alignment as unsigned

2023-01-24T10:40:12+00:00

Use llvm::popcount instead of llvm::countPopulation(NFC)

2023-01-22T20:48:51+00:00

[llvm] Fix comment typos (NFC)

2022-08-07T07:16:14+00:00

[clang] Add support for __builtin_memset_inline

2022-06-10T13:13:59+00:00

In the same spirit as D73543 and in reply to https://reviews.llvm.org/D126768#3549920 this patch is adding support for `__builtin_memset_inline`.

The idea is to get support from the compiler to easily write efficient memory function implementations.

This patch could be split in two:
 - one for the LLVM part adding the `llvm.memset.inline.*` intrinsics.
 - and another one for the Clang part providing the instrinsic as a builtin.

Differential Revision: https://reviews.llvm.org/D126903

[SystemZ] Improve codegen for memset.

2021-12-06T18:10:58+00:00

Memset with a constant length was implemented with a single store followed by
a series of MVC:s. This patch changes this so that one store of the byte is
emitted for each MVC, which avoids data dependencies between the MVCs. An
MVI/STC + MVC(len-1) is done for each block.

In addition, memset with a variable length is now also handled without a
libcall. Since the byte is first stored and then MVC is used from that
address, a length of two must now be subtracted instead of one for the loop
and EXRL. This requires an extra check for the one-byte case, which is
handled in a special block with just a single MVI/STC (like GCC).

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D112004

[SystemZ] Reapply memcmp and memcpy patches.

2021-10-14T08:37:33+00:00

This reverts 3562076 and includes some refactoring as well.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D111733

[SystemZ] Bugfix and refactorization of mem-mem operations

2021-10-14T08:37:33+00:00

This patch fixes the bug that consisted of treating variable / immediate
length mem operations (such as memcpy, memset, ...) differently. The variable
length case needs to have the length minus 1 passed due to the use of EXRL
target instructions. However, the DAGCombiner can convert a register length
argument into a constant one, and whenever that happened one byte too little
would end up being performed.

This is also a refactorization by reducing the number of opcodes and variants
involved. For any opcode (variable or constant length), only the length minus
one is passed on to the ISD node. The rest of the logic is now instead
handled during isel pseudo expansion.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D111729