jofrn e8e3e6e893
[LiveVariables] Mark use without implicit if defined at instr (#119446)
LiveVariables will mark instructions with their implicit subregister
uses. However, it will also mark the subregister as an implicit if its
own definition is a subregister of it, i.e. `$r3 = OP val, implicit-def
$r0_r1_r2_r3, ..., implicit $r2_r3`, even if it is otherwise unused,
which defines $r3 on the same line it is used.

This change ensures such uses are marked without implicit, i.e. `$r3 =
OP val, implicit-def $r0_r1_r2_r3, ..., $r2_r3`.

---------

Co-authored-by: Matt Arsenault <arsenm2@gmail.com>
2025-08-18 08:34:59 -04:00
..
2025-08-01 14:34:56 +02:00

+==============================================================================+
| How to organize the lit tests                                                |
+==============================================================================+

- If you write a test for matching a single DAG opcode or intrinsic, it should
  go in a file called {opcode_name,intrinsic_name}.ll (e.g. fadd.ll)

- If you write a test that matches several DAG opcodes and checks for a single
  ISA instruction, then that test should go in a file called {ISA_name}.ll (e.g.
  bfi_int.ll

- For all other tests, use your best judgement for organizing tests and naming
  the files.

+==============================================================================+
| Naming conventions                                                           |
+==============================================================================+

- Use dash '-' and not underscore '_' to separate words in file names, unless
  the file is named after a DAG opcode or ISA instruction that has an
  underscore '_' in its name.