Stream: git-wasmtime

Topic: wasmtime / Issue #1708 Investigate statically folding opt...


view this post on Zulip Wasmtime GitHub notifications bot (May 14 2020 at 17:59):

fitzgen opened Issue #1708:

Consider the following optimizations:

(=> (ishl $x $C)
    (ishl_imm $C $x))

(=> (when (imul $x $C)
          (is-power-of-two $C))
    (ishl $x $(log2 $C)))

After applying the second optimization to some instruction sequence, then the first optimization can be applied to the result.

But it would be more efficient if we folded the second optimization into the first optimizations RHS:

(=> (when (imul $x $C)
          (is-power-of-two $C))
    (ishl_imm $(log2 $C) $x))

We should make a pass in peepmatic to do this mechanically whenever possible.

view this post on Zulip Wasmtime GitHub notifications bot (May 14 2020 at 17:59):

fitzgen labeled Issue #1708:

Consider the following optimizations:

(=> (ishl $x $C)
    (ishl_imm $C $x))

(=> (when (imul $x $C)
          (is-power-of-two $C))
    (ishl $x $(log2 $C)))

After applying the second optimization to some instruction sequence, then the first optimization can be applied to the result.

But it would be more efficient if we folded the second optimization into the first optimizations RHS:

(=> (when (imul $x $C)
          (is-power-of-two $C))
    (ishl_imm $(log2 $C) $x))

We should make a pass in peepmatic to do this mechanically whenever possible.

view this post on Zulip Wasmtime GitHub notifications bot (May 14 2020 at 18:00):

github-actions[bot] commented on Issue #1708:

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Last updated: Oct 23 2024 at 20:03 UTC