Stream: git-wasmtime

Topic: wasmtime / Issue #1852 Reference type support in MachInst...

Wasmtime GitHub notifications bot (Jun 29 2020 at 23:20):

cfallin commented on Issue #1852:

This is wrong. i128 is supposed to be stored as two i64, just like i64 is supposed to be stored as two i32 on 32bit systems. Storing it in a vector register makes it a lot harder to generate efficient math operations for i128.

Fair enough, removed. It was used internally (produced by and matched by the ABI code) to communicate to store_stack / load_stack that a store/load needs to handle the whole 128-bit vector register, in the case that the regalloc cannot provide a vreg/type associated with a spill. In other words this match arm would not have been triggered by an I128 in the incoming CLIF. But the regalloc should not do this in practice (it only lacks a vreg for a spill/reload when it is a reference from a realreg being spilled to a stackmap slot), so we can just remove the match case. I would expect that when we implement true I128 support, we would lower it to 64-bit ops, and the spill/reload code would not need to reason about I128s.

Wasmtime GitHub notifications bot (Jul 02 2020 at 18:36):

cfallin commented on Issue #1852:

Rebased to latest and updated to use support in regalloc.rs that was just merged. The PR to do a new release of regalloc is pending, so this depends on the bytecodealliance/regalloc.rs repo and git hash directly, to let CI work; will update this before a any merge.

@julian-seward1, this should be ready for review now!

Wasmtime GitHub notifications bot (Jul 02 2020 at 18:41):

cfallin commented on Issue #1852:

(Actually, spoke too quickly re: regalloc -- we just released 0.0.27 so the dep in this PR can use that now.)

Wasmtime GitHub notifications bot (Jul 13 2020 at 20:03):

cfallin commented on Issue #1852:

Rebased again after changes to x64 backend.

@julian-seward1 or @bnjbvr, would you mind reviewing this soon before we land additional new-backend PRs, to reduce the rebase overhead somewhat? Thanks!

Wasmtime GitHub notifications bot (Jul 14 2020 at 17:27):

cfallin commented on Issue #1852:

Addressed, thanks!

Last updated: Dec 23 2024 at 12:05 UTC