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Commit 6a2442e9 authored by Alexander Shaposhnikov's avatar Alexander Shaposhnikov
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[AArch64] Increase AddedComplexity of BIC

This diff adjusts AddedComplexity of BIC to bump its position
in the list of patterns to make LLVM pick it instead of MVN + AND.
MVN + AND requires 2 cycles, so does e.g. MOV + BIC, but the latter
outperforms the former if the instructions producing the operands of
BIC can be issued in parallel.

One may consider the following example:

ldur x15, [x0, #2] # 4 cycles
mvn x10, x15 # 1 cycle (depends on ldur)
and x9, x10, #0x8080808080808080

vs.

ldur x15, [x0, #2] # 4 cycles
mov x9, #0x8080808080808080 # 1 cycle (can be executed in parallel with ldur)
bic x9, x9, x15. # 1 cycle

Test plan: ninja check-all

Differential revision: https://reviews.llvm.org/D133345
parent 31f434ee
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