tree 16c61a0bd971532b7edb04b3ce3cc5a1a4dd0156
parent 1337e279347b91ab8e4d957d770bdd8ca6be6032
author Craig Topper <craig.topper@sifive.com> 1659636987 -0700
committer Copybara-Service <copybara-worker@google.com> 1659637950 -0700

[RISCV] Relax a one use restriction performSRACombine

When folding (sra (add (shl X, 32), C1), 32 - C) -> (shl (sext_inreg (add X, C1), C)
ignore the use count on the (shl X, 32).

The sext_inreg after the transform is free. So we're only making
2 new instructions, the add and the shl. So we only need to be
concerned with replacing the original sra+add. The original shl
can have other uses. This helps if there are multiple different
constants being added to the same shl.

GitOrigin-RevId: a2de12c987339f228f7fa412222f7e7746e220ed